Cholera Biocontrol (vaccines & antibiotics are insufficient)

October 22, 2015

CHOLERA, a VIRULENT, SOMETIMES lethal version of Montezuma’s Revenge, the diarrheal gut scourge bane of travelers, is commonly associated with pesky Vibrio bacteria; though similar symptoms are associated with the sometimes disease-causing and sometimes beneficial E. coli gut bacterium and many other intestinal tract microbes. Cholera is commonly controlled by an integrated management approach, often including proper sewage sanitation, water filtration, antibiotics, vaccines, rehydration therapy and the fortuitous presence of natural enemies known as phages.

Phages, short for bacteriophages, are ‘bacteria-eating’ viruses; the name phage is from the Greek word ‘phagein’, which means ‘to eat’. One might think of cholera as being like the black plague, a no longer relevant disease of the past. But a recent Google News search indicates lethal cholera outbreaks worldwide: From 54 dead in one month in Dar es Salaam, Tanzania, to Rwanda and Nigeria in Africa to Iraq in the Middle East and Haiti in the Americas; with worries about outbreaks in refugee camps worldwide where wars rage and after natural disasters such as earthquakes destroy sanitary infrastructure. In Iraq, “The epidemic is concentrated in the town of Abu Ghraib, situated about 25 kilometers (15 miles) west of the capital, Baghdad, where cholera has claimed at least 10 lives,” according to Iran’s Press TV. “Health Ministry spokesman Rifaq al-Araji has blamed the cholera epidemic in Iraq on low water levels in the Euphrates, noting that simmering temperatures during summer months may have activated the bacterium that causes the deadly disease…Cholera is an acute intestinal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae. It is a fast-developing infection that causes diarrhea, which can quickly lead to severe dehydration and death if treatment is not promptly provided.”

According to a “Major Article” in THE JOURNAL OF INFECTIOUS DISEASES: “Vibrio cholerae serogroup O1 and O139 organisms cause acute, watery diarrhea, with an estimated 100, 000–150, 000 deaths annually…Despite global efforts to improve drinking water quality and sanitation in developing countries, there has been little evidence of a decline in the global burden of cholera in recent years. Interest has therefore increased in the use of cholera vaccines as adjuncts to other preventive and therapeutic measures…Live oral cholera vaccines have the theoretical advantage of simulating infection by natural cholera. Experimental infection of North American volunteers has been shown to protect against cholera upon rechallenge…However, to date no live oral vaccine has conferred protection to cholera-endemic populations when tested in a randomized trial, suggesting that the predictions from studies of volunteers lacking preexisting immunity to cholera may not be readily generalizable to cholera-endemic populations.”

According to the United Nations News Centre: “A global stockpile of vaccines, funded by a number of international organizations and foundations, initially made 2 million doses of the vaccine available. In 2015, with additional funding from the GAVI Alliance, the number of doses available for use in both endemic hotspots and emergency situations is expected to rise to around 3 million. There are several examples in which the vaccine has stopped cholera outbreaks in their tracks, such as in South Sudan in 2014…But new outbreaks are ongoing in South Sudan and Tanzania” in 2015, indicating vaccines to produce natural immunity in conjunction with the best that can be done in the way of sanitation and clean water supplies is not enough. Using phages to produce natural biological control of the cholera bacterium, as part of a low-cost, integrated pest management approach, seems to have been totally and completely neglected, almost as if the successes of natural biocontrol of disease bacteria with phages from the years 1917 into the 1930s and continuing into the present in some parts of the world have been totally purged from the Western medical and public health history books. A costly neglect, in terms of human lives.

“Cholera generated as much horror and revulsion among Europeans as bubonic plague had before it, in part because of the blue-black shriveled appearance of its victims and in part because it could strike anyone without warning and kill in 4 to 6 hours,” according to an overview in Microbiological Reviews which implicated “sailors and colonists” in cholera’s global spread, not just poor sanitation (mixing sewage into drinking water supplies). “Although cholera is treatable with antibiotics and oral rehydration therapy (fluid and electrolyte replacement), it is nevertheless an extremely debilitating and sometimes fatal disease. The severe dehydration and cramps symptomatic of the disease are a consequence of the rapid, extreme loss of fluid and electrolytes during the course of the infection. The diarrhea is caused by the action of cholera toxin (CT), secreted by the bacterium Vibrio cholerae, although in some cases it may be caused by the related Escherichia coli heat-labile enterotoxin (LT).”

Historically, as mentioned in a previous blog post titled “Compost for Sustainable Soil Fertility & Disease Suppression,” Japanese cities adopted a more sustainable approach and thereby escaped the cholera epidemics afflicting London, Paris, India, the rest of Asia and the Americas: “Human waste, euphemistically called night soil, became a valuable soil fertility commodity in old Japan. Perhaps not quite worth its weight in gold, but a valuable commodity bought, sold, traded, and transported long distances from cities to farms. Rather than causing cholera and other diseases by entering the water supply as was common in European cities of the same era, sanitation and composting blessed Japan with multiple dividends…Farmers in old Japan spent their own money to build toilets and urinals along well-traveled roads for public use…” No doubt phages were also part of the integrated mix of methods providing natural biological control of cholera in old Japan, even if the invisibly small phages went unrecognized.

The 20th century use of phages for biological control of cholera and other disease bacteria was pioneered by the self-taught, French-Canadian microbiologist Felix d’Herelle, whose phage work was said by many to also be the foundation for modern molecular biology. An itinerant or journeyman scientist, who spent his life much like the modern-day post-doc, migrating from job to job around the world as he promoted phage therapy, d’Herelle was working with the Pasteur Institute in Paris while French and German troops were lining up against each other on the Western Front in World War I. In North Africa, as early as 1910, d’Herelle was pioneering the use of microbes to control biblical style locust plagues in North Africa, when he first noticed something killing the microbes used to kill the locusts; in other words, a complex ecosystem in which a higher level of natural enemies killed the lower-level natural enemies providing biological locust control.

During a World War I Paris dysentery outbreak, d’Herelle deduced that some patients were benefiting from phages invisibly providing biological control of the disease microbes. D’Herelle’s 1917 article on the subject for the French Academie des Sciences was titled “Sur un microbe invisible antagonistic des bacilles dysenterique” (“On an Invisible Microbe Antagonistic to Dysentery Bacteria”). “D’Herelle claimed that the antagonistic principle was filterable, living and organized, and hence a microbe,” wrote medical historian Ton Van Helvoort. D’Herelle “thought the living nature of the principle was proved by the possibility of transmitting it in a series of cultures of dysentery bacilli.”

Albert Einstein, who won a Nobel Prize for proving unseen forces and counter-intuitive phenomena based on mathematical constructs, agreed with d’Herelle. “The statistical explanation, which d’Herelle argued intuitively, is based on the properties of sampling that can be described by the mathematical expression known as the Poisson distribution,” wrote William Summers in his book, Felix d’Herelle and the Origins of Molecular Biology. “D’Herelle bolstered not only this argument but his own status with his well-known footnote giving Einstein’s opinion of this experiment: ‘In discussing this question with my colleague, Professor Einstein, he told me, as a physicist, he would consider this experiment as demonstrating the discontinuity of the bacteriophage. I was very glad to see how this deservedly-famous mathematician evaluated my experimental demonstration, for I do not believe that there are a great many biological experiments whose nature satisfies a physicist’…Since we have now presented the evidence proving the corpuscular nature of the bacteriophage we will no longer make use of such vague expressions as bacteriophage ‘liquid,’ ‘Fluid,’ or ‘filtrate,’ but will employ instead the more precise term’…The validity of the plaque counting assay and corpuscular nature of phage, however, would remain controversial and divide phage workers into two camps until the early 1940s.”

“The bacteriophage phenomenon was the observation that an abundant and therefore cloudy bacterial culture lysed within a short time to a clear solution under the influence of a filterable lytic ‘principle’,” wrote medical historian Ton van Helvoort. “The interpretation of this phenomenon gave rise to two main opposing positions, represented by Felix d’Herelle and Jules Bordet, who clashed heavily. In 1917, d’Herelle proposed the term “bacteriophage” for the lytic principle and was convinced it was to be characterized as a filterable virus which could lyse the bacterial culture. Therefore, this lysis was a virus disease of the bacteria which he named bacteriophagy. In the 1920s this interpretation was severely criticized by, among others, the bacteriologist and serologist Jules Bordet, who received the Nobel Prize for Medicine in 1919. Bordet’s view was that bacteriophagy was linked with the metabolism of the bacterium, while the involvement of a virus was rejected.” The dispute morphed into a personal vendetta against d’Herelle, whose strong personality was perhaps hated as much as his phage theories and his views on the dangers of vaccination that were considered heretical by the era’s Nobel Prize-winning immunologists.

According to medical historian Dottore Emiliano Fruciano: “In presenting his concepts to the scientific and world community, d’Herelle connected his phage interventions to a theoretical system that clashed with those held by institutional medical science. d’Herelle thought that the reason for natural recovery was not the humoral and cellular mechanisms activated by the immune system, but rather the presence of a virulent phage for the pathogenic bacterium in the host. His observations led him to believe that phage was a common guest of every organism from man to silkworm…d’Herelle concluded that phage was the exogenous agent of natural recovery, leading to ‘spontaneous recovery’…

“Recovery was a case of the prevalence of phage over the bacterium, and death was a case of the prevalence of bacterium over phage,” wrote Fruciano. “Furthermore, d’Herelle hypothesized that phage was able to spread among ill people, mainly via stool; thus, a lack of hygiene, while contributing to infection, would also lead to recovery; phage would have been the reason for the end of epidemics. This characteristic made phage, the recovery agent, transmissible between individuals, just like the agent of disease…

“In support of his theory of natural recovery, d’Herelle cited exemplary phenomena, including recovery following exposure to cholera. In cholera, patients generally convalesced after two or three days (sometimes within 12 hours) of initial symptoms; even ‘artificial’ recoveries through phage therapy often occurred after 24 hours. However, according to d’Herelle, observations from many animal diseases had demonstrated that it took many more days for immunity to become effective in the fight against infection. To explain natural recovery through the mechanisms of immunity was not possible because of the timing.

“Moreover, in diseases such as typhus and plague, which are characterized by strong immunity, relapses were possible during convalescence. This would mean that the patient, although convalescing, was still not immune. In these kinds of pathologies, typically typhus and plague, immunity usually lasts forever, yet immunity only comes into play 20 days following convalescence. According to d’Herelle, ‘Immunity, far from being the cause of recovery, is a consequence of recovery’. Further confirmation of d’Herelle’s theory was given by the statistics of the three hospitals in Calcutta, India. Paradoxically, the lowest rate of mortality for cholera (27%) was recorded at the hospital for poor people, the Campbell Hospital, while the highest rate of mortality (86%) was recorded at a hospital for rich people, the European Hospital – a hospital recognized in 1926 for its wealthy patients and hygienic conditions. There were fewer deaths at the hospital where care and hygiene were poor, that is, where the possibility for the development and dissemination of virulent phage or the recovery agent were best.”

The cholera and phage biocontrol case in general became intolerably heretical to many in the scientific medical establishment, what with d’Herelle’s warnings against the dangers of conventional vaccinations and the radical challenge to conventional consensus medical theories supported by immunologists who had won Nobel Prizes in medicine, said Fruciano: “According to d’Herelle, immunity and recovery were two different processes; only after the bacteriolytic action of phage could immunity be developed. Furthermore, there were two kinds of immunity: heterologous immunity, linked to the presence of phage activity against the pathogen, and homologous immunity, linked to immune system activity.

“…man contracts cholera because his immune system is not able to neutralize the bacterium. In d’Herelle’s opinion, in the case of patients with cholera, recovery occurs because of the presence of a virulent phage for Vibrio cholerae as a result of heterologous immunity, not because of natural or homologous immunity. d’Herelle found that the administration of phage resulted not only in a quick recovery, but also lasting immunity. He also asserted that a suspension of phage had strong immunizing power (here in the traditional sense) because the bacterial substances dissolved by phage action induced immune system reactions… d’Herelle’s findings were contrary to the conclusions of Metchnikoff, Bordet and Ehrlich, the founders of immunology…phage therapy efficacy would have required a revision of the current explanation of natural recovery…In other words, the proof of efficacy of phage therapy was equivalent to the proof of the truthfulness of d’Herelle’s heretical theories. Thus, to verify the efficacy of phage therapy and prevention measures, the principles of modern medicine were at stake; this was a paradigm shift for the scientific community.”

Of course, in the early years of the 20th century, prior to the invention of the electron microscope to provide visual evidence, the immunologists could plausibly argue against the existence of phages (despite Einstein’s endorsement); and in the absence of modern genomics, indeed before DNA and RNA were implicated in heredity, matching the right mixture of phages with a particular disease bacterium was perhaps more art than science, an art in continuous successful practice in just a few places such as the ex-Soviet Republics of Georgia and Russia, and Poland. Also, early 20th century medical experiments are not considered rigorous by current standards. All of which makes the several hundred successful phage experiments and interventions against cholera, plague, typhus and other diseases subject to blanket dismissal; and, hence, the absence of natural biological control from Western medical practices, medical schools, and institutional research agendas.

“The following details some of the most sensational results in phage prophylaxis that would seem to contradict the eventual dismissal of d’Herelle’s works,” stated Fruciano. “In 1927, an epidemic of Asiatic cholera was halted at its start in several villages with 2000 to 3000 Punjabi inhabitants via two methods of phage prophylaxis delivery: the first was the addition of potent, individually dosed phage preparations, and the second was the administration of phage prophylaxis to local water supplies. In both scenarios, the epidemic was terminated within 48 hours; in the past, the same result was achieved through traditional interventions within a 26-day time period.

“…at the St Mary Hospital in London, England, where penicillin was first discovered, Himmelweit developed a cross-therapy involving a combination of phage and penicillin to reduce the possibility of penicillin-resistant bacteria. This solution was very promising…Above all, the conjoined administration of phage and penicillin gave positive outcomes in clinical trials. It is likely that this experimental solution worked well because, as it is known today, the mechanisms by which phage and penicillin kill bacteria are different. Unfortunately, this alternative use of phage, in combination with penicillin, has been abandoned. Why has this possibility been forgotten despite the fact that antibiotic-resistant bacteria appeared as soon as penicillin was introduced into medical practice?

“…Summers, a historian of medicine who delved deeply into d’Herelle’s scientific works, speaks of the “Soviet Taint” as a plausible reason for the lack of interest in phage as an antimicrobial agent. Following World War II, phage therapy research continued only in eastern European countries, and “d’Herelle’s Cure” became “Stalin’s Cure”. According to Summers, phage therapy and prophylactic measures became ideological symbols of divisions and disagreements between western and eastern countries, partially explaining the lack of interest in phage as an antibacterial agent in Western medical science.”

Food Sweetener Safely Slays Insects

August 27, 2015

CERTAIN SUGARS CONSIDERED SAFE as sweeteners in the human food supply can double as environmentally-friendly pest remedies, and even make biological control of insects by beneficial fungi more practical for households, farms and gardens. Considering that caffeine from coffee grounds can be used against deadly dengue mosquitoes and that a variety of traditional herbs can blast away bed bugs, insecticidal sugar compounds should come as no surprise. Perhaps the only remedy more surprising is that rain water or simulated rain sprays from hoses or irrigation equipment can safely wash away pests with no toxic pesticide residues to worry about in the environment.

Using sugars directly to slay insects is somewhat unusual. However, sugars are commonly used as attractants, for instance to lure fruit flies, moths or ants to baits and traps both for population control and as a survey method or monitoring tool. California citrus growers have a long history of using sugar sprays as an IPM (integrated pest management) strategy to lure fruit-scarring citrus thrips to organic or botanical formulations of ryania (“from woody stem and root materials of plants of the genus Ryania”) or sabadilla (alkaloids from seeds of a lily bulb, Schoenocaulon officinale). “INTEGRATED PEST MANAGEMENT implies that techniques used to manage one pest species should not disrupt techniques used to manage other pests of the same crop,” wrote J.D. Hare and Joseph Morse in the Journal of Economic Entomology. “In citrus pest management in California, this situation is well illustrated in the choice of pesticides for the management of one major pest, citrus thrips, Scirtothrips citri (Moulton), without disruption of several effective biological control agents of the other major pest, California red scale, Aonidiella aurantii (Maskell).”

That sugars can be lethal to pests and be a source of environmentally-friendly pesticides is not exactly intuitive. “Potential of the non-nutritive sweet alcohol erythritol as a human-safe insecticide” was the strangely intriguing title of Drexel University’s Sean O’Donnell’s presentation at the Entomological Society of America (ESA) annual meeting. Many of the details were previously published in PLoS ONE, an open access journal, and in part because of the origins of the research in a grade school science project by one of the researcher’s sons, aspects of the story have been widely reported in various media. “Erythritol is a zero-calorie sweetener found in fruits and fermented foods,” summarized Lauren Wolf in Chemical & Engineering News, and “is Generally Recognized As Safe by the Food & Drug Administration and has been approved as a food additive around the globe.”

“Many pesticides in current use are synthetic molecules such as organochlorine and organophosphate compounds,” and “suffer drawbacks including high production costs, concern over environmental sustainability, harmful effects on human health, targeting non-intended insect species, and the evolution of resistance among insect populations,” write the researchers in PLoS ONE. “Erythritol, a non-nutritive sugar alcohol, was toxic to the fruit fly Drosophila melanogaster. Ingested erythritol decreased fruit fly longevity in a dose-dependent manner, and erythritol was ingested by flies that had free access to control (sucrose) foods in choice and CAFE (capillary feeding assays) studies…

“We initially compared the effects of adding five different non-nutritive sugar substitutes (Truvia, Equal, Splenda, Sweet’N Low, and PureVia,” wrote the researchers in PLoS ONE. “Adult flies raised on food containing Truvia showed a significant reduction in longevity…We noted that adult flies raised on food containing Truvia displayed aberrant motor control prior to death. We therefore assayed motor reflex behavior through climbing assays…Taken together with our longevity studies, these data suggested some component of the non-nutritive sweetener Truvia was toxic to adult Drosophila melanogster, affecting both motor function and longevity of this insect…

“Our initial analysis of sweeteners included two sweeteners that contained extracts from the stevia plant, Truvia and Purevia. While adult flies raised on food containing Truvia showed a significant decrease in longevity compared to controls, this was not the case for flies raised on Purevia. These data suggest stevia plant extract was not the toxic element in these sweeteners. Purevia contains dextrose as a bulk component, while Truvia contains erythritol as a bulk component…To determine if erythritol was the toxic component of Truvia, we repeated our longevity studies on food containing equal weight/volume (0.0952 g/ml) of nutritive sugar control sucrose, and non-nutritive sweeteners Truvia, Purevia, and erythritol. We assured the flies were successfully eating the foods containing these sweeteners through dye labelling the food with a non-absorbed blue dye (blue food), and visual confirmation of blue food present in fly abdomens and proboscises daily…The average percentage of blue abdomens throughout the study were 97.46%.”

“These data confirm all treatment foods (including Truvia and erythritol treatments) were consumed by adult flies, and suggest mortality was not due to food avoidance and starvation…A large body of literature has shown that erythritol consumption by humans is very well tolerated, and, indeed, large amounts of both erythritol and Truvia are being consumed by humans every day throughout the world. Taken together, our data set the stage for investigating this compound as a novel, effective, and human safe approach for insect pest control. We suggest targeted bait presentations to fruit crop and urban insect pests are particularly promising.”

Interestingly, a few decades ago UK researchers found that the sweeteners (sugar alcohols; polyols) erythritol, glycerol and trehalose rendered more effective several insect biocontrol fungi, Beauveria bassiana, Metarhizium anisopliae and Paecilomyces farinosus. These insect-killing fungi need a relative humidity (RH) near 100% for germination of their conidia (seed-like propagules). “Conidia with higher intracellular concentrations of glycerol and erythritol germinated both more quickly and at lower water activity,” wrote UK researchers J.E. Hallsworth and N. Magan in the journal Microbiology. “This study shows for the first time that manipulating polyol content can extend the range of water availability over which fungal propagules can germinate. Physiological manipulation of conidia may improve biological control of insect pests in the field…Although fungal pathogens have been used to control insect pests for more than 100 years, pest control has been inadequate because high water availability is required for fungal germination.”

Curiously, erythritol and glycerol, besides being sweetening substances, also function as antifreeze compounds. Certain Antarctic midges, known as extremeophiles for living in an ultra-cold habitat, ingest and sequester erythritol from their food plants; and as antifreeze it protects the adult flies from freezing. Indeed, many mysteries remain. Besides being found in green plants like stevia and in lower amounts in fruits, erythritol is found in certain mushrooms, lichens and algae. Human and animal blood and tissues apparently have low endogenous levels of erythritol; and erythritol is a yeast fermentation product (hence in sake, beer, wine). In human medicine, erythritol has been used for coronary vasodilation and treating hypertension; and according to Japanese microbiologists, erythritol ingestion may mean fewer dental cavities (caries) than sucrose sugar.

Grapes Love Tobacco & Sage

June 13, 2015

GRAPE VINES GAIN and pests suffer when TOBACCO and SAGEBRUSH grow in the same neighborhood. For example, Chinese experiments show that when tobacco roots intermingle with grape roots, vineyards soils are progressively cleansed of the dreaded soil-dwelling phylloxera aphid; the same phylloxera aphid that almost completely destroyed French grape growing in the 1800s, before resistant rootstocks were discovered. In recent decades, the phylloxera aphid has evolved new forms that destroy formerly-resistant rootstocks. But on the positive side, the phylloxera plague in nineteenth century French vineyards was a major catalyst for innovations such as the development of modern scientific agriculture and modern methods for fumigating or disinfesting sick soils.

Tobacco plants get a bad rap today, as the source of abused and addictive products with adverse health effects. But it was not always so, and need not be so today, write David A. Danehower and colleagues in the book, Biologically Active Natural Products: Agrochemicals: “When Columbus first arrived on the shores of North America, he found Native Americans growing and using a plant unknown to Europeans. This plant held great spiritual significance to Native Americans. Scientists who followed in the footsteps of the early North American explorers would later name this plant tobacco. Tobacco (Nicotiana tabacum) farming began in the early 1600s near the Jamestown colony in Virginia. As the use of tobacco products for smoking, chewing, and snuff was promoted in Europe, tobacco became a leading item of commerce between the colonies and England. Notably, George Washington and Thomas Jefferson both farmed tobacco. Thus, the history of America is inextricably linked with the history of tobacco production.”

The specific idea of interplanting tobacco with grapevines to control soil pests like phylloxera aphids is apparently a recent Chinese agricultural innovation. Why no one thought of it before is a mystery, as nicotine from tobacco plants has a long history as a fumigant and sprayed insecticide; and more recently sweet “sugar esters” (fructose, glucose, fatty acids) have been singled out from among the several thousand chemical compounds in tobacco as “new” natural insecticides (some fungi and other microbes are also killed). Perhaps agricultural tradition plays a role, as the Chinese have an ancient agricultural heritage that includes pioneering biological pest control (e.g. predatory ants to control citrus orchard pests) and routinely interplanting compatible plants for their pest-fighting and mutually beneficial effects. Of course, growing cover crops and beneficial insect plants like sweet alyssum in grape rows is becoming more common. And since ancient times, the Mediterranean areas of Europe and the Middle East have had grape vineyards interspersed with oaks (corks, barrels for wine grapes), olive trees and crops such as wheat. But never before has tobacco been grown among grape vines to control soil pests. Indeed, modern farmers seem to favor pumping liquid chemicals and volatile gases into the soil to combat soil pests.

Perhaps as close as a nineteenth century French grape grower came was Bernardin Casanova of Corsica, France, who in 1881 patented a liquid mixture of grape distillates, Corsican tobacco, spurge, laurel, grain straw, burnt cork and soap that was rubbed and poured on the base of grapevines to kill phylloxera. In California, which has native plants that are every bit as insecticidal as nicotine from tobacco, the only anti-phylloxera interplanting seems to have been new resistant rootstocks to eventually take the place of the old. In essence, a concession of failure and a starting over with new rootstock (and pulling out the old phylloxera-infested vines).

Like Mr. Casanova in nineteenth century France, the modern Chinese researchers started out with a watery solution containing tobacco; but in a bit more scientific fashion with controlled tests of the tobacco solution on young greenhouse-grown grape vines. “The results showed that aqueous extracts of tobacco had certain alleviating effects on phylloxera infection,” according to a 2014 abstract from the journal Acta Entomologica Sinica. “Both the aqueous extracts of tobacco at the concentration of 20 mg/mL and 50 mg/mL had an inhibition to phylloxera infection,” with a 50% reduction in phylloxera infection within 3 weeks (along with a reduction of fungal invaders that kill injured grape roots).

Chinese tobacco-grape laboratory and field studies were also reported in the Journal of Integrative Agriculture in 2014. The lab studies indicated that tobacco extracts in water were indeed a valid herbal (botanical) remedy against phylloxera aphids. In three years of field tests with tobacco interplanted in infested grape vineyards, phylloxera infestations of grape roots steadily decreased each year. “Tobacco was used as the intercropping crop because it includes nicotine, which is a source of bio-insecticides,” said the researchers. “The production of new grape roots was significantly higher in the intercropping patterns than in the grape monoculture in 2010, 2011 and 2012, and the vines gradually renewed due to the continuous intercropping with tobacco over three years…The results indicated that the secondary metabolites of tobacco roots had released to soil and got to the target pest.” Tobacco intercropping effects on grape plants was also measurable in terms of “cluster number per plant, cluster weight, cluster length, cluster width, berry number per cluster, mean berry diameter in the mid portions of the cluster, carbohydrate content, fruit color index, leaf width and branch diameter.” The researchers expect that this “Successful intercropping with tobacco” will stimulate more research with other insecticidal plants to disinfest vineyard soils.

We could probably end the blog item here, or have a second article as part II, but we have some interesting interactions among sagebrush and tobacco plants that can spillover to grape vineyards. Oddly enough, sagebrush and tobacco seem to get along very well. According to M.E. Maffei, writing in the South African Journal of Botany: “Aerial interaction of the wild tobacco (Nicotiana attenuata) and sagebrush (Artemisia tridentata subsp.) is the best-documented example of between-plant signaling via above-ground VOCs (Volatile Organic Compounds) in nature.” Wounded or “Clipped sagebrush emits many volatiles, including methyl jasmonate, methacrolein, terpenoids, and green leaf volatiles.” These sagebrush volatiles (VOCs) stimulate nearby tobacco plants to become less hospitable to caterpillar pests (fewer in number). The process is called priming and results in plants producing more chemicals deleterious to pests. For readers desiring all the details and more theory: In 2006, Kessler et al. published in a journal called Oecologia under the title “Priming of plant defense responses in nature by airborne signaling between Artemisia tridentata and Nicotiana attenuata.”

Big Sagebrush, known scientifically as Artemisia tridentata, is a native North American plant that can reach 4 meters in height and live from 30 to over 200 years in arid desert environments by using hydraulic lift to pump water from deep soil layers. The plants are a rich and underutilized source of medicinal compounds, insecticides, fungicides, natural preservatives, etc. Worldwide there are at least 500 Artemisia sagebrush species, many used in traditional medicines (e.g. China), cosmetics, insect repellents, and as spices and flavorings in foods. For example, Artemisia annua has attracted attention to combat malaria. Readers desiring a crash course in Artemisia species and their bio-active essential oils will find it online in an excellent 24-page review article in a journal called Molecules.

Big Sagebrush is “found in arid regions of North America from steppe to subalpine zones, dry shrub lands, foothills, rocky outcrops, scablands, and valleys,” wrote Christina Turi and colleagues in 2014 in the journal Plant Signaling & Behavior. “Traditionally, species of Big Sagebrush have been used as a ceremonial medicine to treat headaches or protect individuals from metaphysical forces. A total of 220 phytochemicals have been described in A. tridentata and related species in the Tridentatae. Recently, the neurologically active compounds melatonin (MEL), serotonin (5HT), and acetylcholine (Ach) were identified and quantified.” In other words, sagebrush plants and human brains and nervous systems have a lot in common.

Indeed, galanthamine, a botanical drug treatment for mild to moderate Alzheimer disease, can also be used to “treat” sagebrush. Galanthamine, which is named after the snowdrop plants (Galanthus species) where it was discovered, is also found in Narcissus and other common bulbs. Galanthamine is, according to researchers Turi et al., “a naturally occurring acetylcholinesterase (AchE) inhibitor that has been well established as a drug for treatment of mild to moderate Alzheimer disease.” Why bulb plants produce chemicals affecting both Alzheimer disease (human nervous systems) and sagebrush plants is a good question. One theory is that plants release these chemicals into the environment to communicate with and influence the behavior of other plants, and also perhaps deter or otherwise influence herbivorous animals. Environmentalists, overly preoccupied with worries about carbon dioxide and GMOs, might ponder the fact that human chemicals with medicinal effects released into the environment might be the bigger threat, affecting plants and ecosystems in ways not yet fully appreciated that may comeback to bite us.

The Western USA is known for its vast expanses, perhaps 50 million acres with Big Sagebrush, some of which is being displaced for vineyards in isolated valleys in the Pacific Northwest. I particularly like the description of the Big Sagebrush ecosystem at the Sage Grouse Initiative: “To many of us, sagebrush country symbolizes the wild, wide-open spaces of the West, populated by scattered herds of cattle and sheep, a few pronghorn antelope, and a loose-knit community of rugged ranchers. When you stand in the midst of the arid western range, dusty gray-green sagebrush stretches to the horizon in a boundless, tranquil sea. Your first impression may be of sameness and lifelessness—a monotony of low shrubs, the over-reaching sky, a scattering of little brown birds darting away through the brush, and that heady, ever-present sage perfume.”

About 90% of the native sagebrush steppe habitat in the eastern Washington grape growing area was removed to make way for the vineyards. But the 10% remaining sagebrush habitat may have important ecological benefits, such as improved natural or biological pest control in the vineyards. One suggestion is to leave some of the native Big Sagebrush around vineyards, for its beneficial ecological effects. “Perennial crop systems such as wine grapes have begun using cover crops and hedgerows to increase beneficial insects and promote sustainable vineyard management in areas like New Zealand and California,” Washington State University researcher Katherine Buckley told the 2014 Entomological Society of America (ESA) annual meeting in Portland, Oregon. “However, in arid wine growing regions such as eastern Washington, cover crops are often prohibitively expensive due to water costs. We wanted to determine if native plants, which require little or no irrigation, could be used to increase beneficial insects and enhance conservation biological control of vineyard pests in eastern Washington.”

The native sagebrush steppe ecosystem has a wide range of plants, but is characterized by species such as big sagebrush (Artemisia tridentata), rabbitbrush (e.g. Chrysothamnus, Ericameria spp.), bitterbrush (Purshia spp.) and perennial bunchgrasses (e.g. Agropyron, Stipa, Festuca, Koeleria, Poa spp.). The Big Sagebrush ecosystem is richer in species than meets the eye at first glance. Over 100 species of birds (e.g. sage grouse, sage thrasher, sage sparrow and Brewer’s sparrow) forage and nest in sagebrush communities, and they could provide a lot of insect biocontrol at less cost and with less environmental impact than chemical sprays.

A U.S. Forest Service report called Big Sagebrush a keystone species and “a nursing mother” to “31 species of fungi, 52 species of aphids, 10 species of insects that feed on aphids, 42 species of midges and fruit flies that induce galls, 20 species of insects that parasitize the gall inducers, 6 species of insects that hibernate in big sagebrush galls, 18 species of beetles, 13 species of grasshoppers, 13 species of shield-back katydids, 16 species of thrips, 74 species of spiders, 24 species of lichens, 16 species of paintbrushes, 7 species of owl-clovers, 5 species of bird’s beaks, 3 species of broom rapes, and a host of large and small mammals, birds, and reptiles.”

“After locating vineyards with some form of native habitat restoration in four different growing regions of eastern Washington, yellow sticky traps and leaf samples were used to monitor beneficial and pest insect numbers in the habitat restored vineyards and nearby conventional vineyards over a three year period,” said Buckley. The native plants, which are adapted to the region’s hot summers and cold winters, are home to at least 133 insect species. Native habitat vineyards had fewer pest insect species; and higher populations and a higher diversity of beneficial insects. Anagrus wasps, which are known to parasitize pesky grape leafhoppers, were most abundant in Big Sagebrush. More amazingly, this leafhopper biocontrol wasp was found year-round in Big Sagebrush, even when the plant was not flowering. No other plant, not even the photogenic wild roses planted at the end of vineyard rows and admired by tourists, hosted the tiny leafhopper biocontrol wasp year-round.

Garden herbs such as thyme (Thymus ssp.), mugwort (Artemisia ssp.) and fennel (Foeniculum ssp.) have all been tested in vineyard interrows because they are fungicidal against Botrytis cinerea, a fungus attacking grape clusters, and boost soil micro-nutrients like copper, manganese and zinc. Maybe at some point in time, the Chinese interplantings of tobacco and alternating strips of Big Sagebrush (or other Artemisia species) and garden herbs will all get integrated together with other cover crops and native hedgerows into grape vineyards for a more biological or natural approach to agriculture. With sagebrush and tobacco, we have only scratched the surface of vineyard possibilities.

Silicon Bed Bug Weaponry

May 4, 2015

BED BUGS CAN be spiked and trapped by tiny spears like leaf hairs, and can become dehydrated or dessicated and rendered harmless by certain forms of silicon, the second most abundant element in planet Earth’s crust (28%) after oxygen (47%). That silicon can be the bane of bed bugs is indeed odd when one considers that silicon permeates our world from beach sands, opals, agates and quartz crystals to sandpaper, semiconductors, glasses, ceramics, optical fibers and cosmetic products. Indeed, the famous French scientist and silkworm entomologist, Louis Pasteur, whose name has become synonymous with the germ theory of medicine, predicted silicon’s eventual service in human medicine; though Pasteur was probably not thinking along the lines of silica gels and desiccant diatomaceous earth dusts as remedies for the 21st century’s worldwide medical plague of bed bugs.

Despite its commonness in nature and the human environment and potential uses in human medicine, the use of silicon products comes with caveats to users, who might want to wear sufficient protective clothing and respirators to avoid inhaling the products. Strangely enough, that much maligned metabolic waste product, carbon dioxide, which along with sunlight is essential to photosynthesis and life on planet Earth, is perhaps a safer component (e.g. as a lure or attractant) when integrated into bed bug traps. Food grade diatomaceous earth made from freshwater diatoms is considered relatively nontoxic; whereas filtering grade diatomaceous earth (e.g. the type used for swimming pool filters) is a crystalline form with inhalation toxicity.

“Louis Pasteur (1822-95) said that silicon would prove to be a treatment for many diseases and in the first quarter of the twentieth century there were numerous reports by French and German doctors of sodium silicate being used successfully to treat conditions such as high blood pressure and dermatitis,” wrote British chemist John Emsley in his superb compendium, Nature’s Building Blocks (An A-Z Guide to the Elements). “By 1930, such treatments were seen to have been in vain and the medication fell out of favor. So things rested, until the discovery that silicon might have a role to play in human metabolism, and then followed suggestions that it could have a role in conditions such as arthritis and Alzheimer’s disease, but no new treatment based on these suggestions has yet emerged. Meanwhile, silicon continues to be linked with a disease of its own: silicosis. Miners, stone-cutters, sand-blasters and metal-grinders develop this lung condition which is a recognized occupational disorder caused by the inhalation of minute particles of silica…” Symptoms include coughing, wheezing and shortness of breath; a more aggressive form of silicosis associated with certain types of asbestos can develop into lung cancer and has been a rich source of litigation for occupational exposure in the USA.

While silica products should be used sparingly (a caution that should also apply to most sprays) or not at all by some people (e.g. existing respiratory problems; perhaps seek a medical opinion before using), they might prove for many others the tipping point for winning the bed bug war as part of an integrated approach that controls bed bugs (many of which are pesticide resistant) using a multiple arsenal of weapons including herbal oils, clutter reduction, heat, sealing crack and crevice harborages, traps, pheromones, carbon dioxide, vacuuming under baseboards, etc.

At the 2014 Entomological Society of America (ESA) annual meeting, Kyeong-Yeoll Lee of South Korea’s Kyungpook National University (Daegu) reported that silica in the form of diatomaceous earth (Perma-Guard(TM) or Fossil-Shell(R)) acted as a synergist when heat (hot air) fumigations substituted for chemical fumigants such as methyl bromide. Though the test insect was Indian meal moth, a worldwide pest of stored grain and many other packaged agricultural products, it would not be surprising to find that heat treatments combined with silica products like diatomaceous earth will also prove efficacious and perhaps also synergistic against bed bugs. Indeed, heat treatments may induce bed bugs to move around more, which could hasten contacting diatomaceous earth and water loss.

At the same 2014 ESA meeting, Virginia Tech (Blacksburg, VA) researcher Molly Stedfast provided some impressive results via the time-consuming process of first educating apartment residents about bed bugs and then painstakingly vacuuming along baseboards to suck up as many bed bugs as possible before applying the silica products under the baseboards to further reduce bed bug populations. This integrated (IPM; integrated pest management) approach required quite a bit of manual labor, as furniture had to be moved to gain access to the baseboards before vacuuming and then applying silica gel or dust products.

Stedfast tested two silica products, Mother Earth(TM) D, a highly-absorptive desiccant dust made from 100% freshwater diatomaceous earth, and CimeXa(TM) Insecticide Dust, a 100% amorphous silica gel. The silica dust or gel injures the insect cuticle (outer protective “skin”), letting water leak out and leading to dehydration (providing relative humidity is not extremely high, above 81%; and free water is unavailable). Both the diatomaceous earth and silica gel products were “very effective at killing bed bugs even at 10% of the label rate.” Going above the label rate was a waste of resources, as only so much product can contaminate the bed bugs. Bed bugs can die within 24 hours of contacting the silica products, but air currents that blow the dusts around can be a problem; also the products need to stay moist and not dry out to be effective. Among Stedfast’s biggest headaches is the application equipment, which was not very robust.

The patent literature reveals that inventors such as Roderick William Phillips in Vancouver are working on improved spray apparatuses for applying diatomaceous earth: “There is disclosed a spray apparatus for holding contents comprising diatomaceous earth and a compressed propellant for propelling the diatomaceous earth. There is also disclosed use of diatomaceous earth to control a population of bedbugs…diatomaceous earth, a naturally occurring siliceous sedimentary rock that includes fossilized remains of diatoms. However, known methods of applying diatomaceous earth can be cumbersome. For example, known methods of applying diatomaceous earth may undesirably require handling the diatomaceous earth, for example to transfer the diatomaceous earth from a container not having an applicator to a separate applicator apparatus. Also, known applicator apparatuses may apply diatomaceous earth unevenly, which may be wasteful or ineffective. In general, known methods of applying diatomaceous earth may be sufficiently complex so as to require professional involvement, which may undesirably add to cost and delay of bedbug treatment. Also, numerous types of diatomaceous earth are available, and different types of diatomaceous earth vary widely and significantly from each other. It has been estimated that there are approximately 100,000 extant diatom species…and may vary widely and significantly in size and shape across a very large number of diatom species…”

At the University of British Columbia (Vancouver), Yasmin Akhtar and Murray Isman demonstrated that both diatomaceous earth and herbal or botanical compounds such as neem, ryania and rotenone are to varying degrees transported by adult bed bugs and contaminate other adults and younger bed bug nymphs. “Our data clearly demonstrate horizontal transfer of diatomaceous earth and botanical insecticides in the common bed bug,” said Akhtar and Isman. “Use of a fluorescent dust provided visual confirmation that contaminated bed bugs transfer dust to untreated bed bugs in harborage. This result is important because bedbugs live in hard-to-reach places and interaction between conspecifics can be exploited for delivery and dissemination of management products directed at this public health pest…This result is important because bedbugs live in hard-to-reach places (cracks, crevices, picture frames, books, furniture) and as such interaction between the members of the colony can be exploited for delivery and dissemination of control products.”

At the 2014 ESA annual meeting, Akhtar suggested protecting travelers and suppressing bed bug transit by building diatomaceous earth into luggage, mattresses and fabrics. Diatomaceous earth provided 96% repellence; bed bug mortality was zero at 24 hours, but 93% after 120 hours. Diatomaceous earth could also be applied to box springs, dressers and headboards, and under carpets and inside drywall. A diatomaceous earth aerosol provided 81% bed bug mortality at 30 days, and was still active and being transferred from dead bed bugs to live bed bugs.

Diatom species mined for diatomaceous earth are stunning in their architectural variety and beauty. Ultimately, the silicon secrets of living diatoms has the potential to transform “the manufacture of siloxane-based semiconductors, glasses, ceramics, plastics, elastomers, resins, mesoporous molecular sieves and catalysts, optical fibers and coatings, insulators, moisture shields, photoluminescent polymers, and cosmetics,” wrote UCSB marine scientist Daniel E. Morse. “The manufacture of these materials typically requires high temperatures, high pressures or the use of caustic chemicals. By contrast, the biological production of amorphous silica, the simplest siloxane [(SiO2)n], is accomplished under mild physiological conditions, producing a remarkable diversity of exquisitely structured shells, spines, fibers and granules in many protists, diatoms, sponges, molluscs and higher plants. These biologically produced silicas exhibit a genetically controlled precision of nanoscale architecture that, in many cases, exceeds the capabilities of present-day human engineering. Furthermore, the biological productivity of siloxanes occurs on an enormous scale globally, yielding gigatons per year of silica deposits on the floor of the ocean. Diatomaceous earth (composed of the nanoporous skeletons of diatoms) is mined in great quantities from vast primordial deposits of this biogenic silica.”

Herbal Oils Blast Bed Bugs

March 28, 2015

HERBAL OILS such as NEEM can reduce bed bug populations when integrated with other pest control technologies such as traps. As desperation hits with more bed bug populations resistant to more conventional synthetic pesticides, more herb and essential oil formulations and fumigations, as well as silicon dioxide-based gels and dusts such as diatomaceous earth, are being integrated with other bed bug remedies such as clutter reduction and heat fumigation.

Those in thrall to chemical industry protocols adhere to the standard that a remedy must kill 95% in laboratory tests. But it is most often a hypocritical standard, as over time bed bugs are almost guaranteed to become genetically selected for resistance to widely used synthetic pesticides. According to Virginia Tech researchers: “A frightening resurgence of bed bug infestations has occurred over the last 10 years in the U.S. and current chemical methods have been inadequate for controlling this pest due to widespread insecticide resistance…While DDT was initially effective for bed bug control, resistance to the cyclodienes was well documented among different bed bug populations by 1958…bed bugs had developed resistance to organophosphate insecticides, including malathion by the 1960s…While there have been many hypotheses regarding the cause of the bed bug resurgence, the cause is at least partially explained by bed bug resistance to insecticides, in this case, those in the pyrethroid class,” including deltamethrin resistance in New York City bed bugs.

To that conclusion, I would add “over-reliance on synthetic chemical pesticides” to the exclusion of designing habitations to be inhospitable to bed bugs and alternative control methods. Oddly enough, herbal remedies not killing 95% are often subject to persecutory calls of marketplace banishment by the EPA, FDA, FTC or one of the myriad other regulatory bureaucracies. An Alternative in the Internet age is letting people decide for themselves via Internet search engines before buying. To some extent, government regulation of herbal pest control efficacy is unnecessary when scientific test results can be posted on the Internet and debated.

An integrative approach can make excellent use of herbal remedies providing perhaps 40% or 60% bed bug reduction; in conjunction with heat treatments, sharp silicon dioxide crystals and other remedies that collectively might add another 30%, 40% or 50% bed bug reduction. It’s all mathematics, which many people hate; but nonetheless a 60% bed bug reduction from an herbal remedy combined with a 40% reduction from clutter reduction, heat fumigation or traps can easily equal over 95% control (the laboratory standard adhered to by those one-trick chemical ponies sometimes called “nozzle heads”).

In other words, herbal oils and other alternative treatments can leverage themselves when intelligently combined with other pest control methods such as heat, clutter reduction and traps. That should be intuitive, but it runs counter to the entomology training of the average PhD in the USA. The late “Professor (Robert) van den Bosch of the University of California was one of the developers of Integrated Pest Management” (IPM) and an advocate of biological controls; and he made the case for a multi-faceted approach to cotton and food crop pests long ago in books like The Pesticide Conspiracy (University of California Press).

Bed bugs and the urban environment of hotels, apartments, cracks, crevices, mattresses, trains, buses, backpacks and luggage of course present a different set of problems than a homogeneous field of crops or a laboratory spray arena. But you be the judge of whether herbal fumigations work against bed bugs: At the Entomological Society of America annual meeting, Korean researcher Jun-Ran Kim (Rural Develop Admin, Suwon-si Gyeonggi-do, South Korea) compared 120 herbal or botanical essential oils to the best conventional pesticides for controlling insecticide-susceptible and insecticide-resistant adult bed bugs hiding in protected places (as bed bugs do; e.g. cracks, crevices, inside electrical sockets).

Kim singled out two essential oils, those from peppermint (Mentha piperita) and myrtle (Myrtus communis) plants, as most effective and worth further development as bed bug fumigants. So, should the headline read: “Essential Oils a Failure as Bed Bug Fumigants,” as 118 of 120 essential oils did not make the cut. Indeed, fewer than 2% of the botanical oils tested, peppermint and myrtle, were singled out as potential bed bug fumigants. Or should the headline read: “Essential Oils Effective Bed Bug Fumigants,” or “Peppermint and Myrtle Oils Prove Essential Oils Can Work as Bed Bug Fumigants.”

Rue, an ancient herb, needs to be tested against bed bugs. Natural products researchers report: “An infusion of Ruta chalepensis leaves rubbed onto skin has been purported to be repellent to mosquitoes and other insects by farmers and shepherds in rural and mountainous areas of Marche and Latium, Central Italy. In the same Italian countryside, Ruta graveolens leaves were set under the bed to repel bugs and mice (Guarrera 1999). A decoction of Ruta species also has been used topically against scabies, lice, and fleas, to repel insects and to treat intestinal worms in livestock.”

Intriguingly, rather than following up on rue under the bed to fight bed bugs, Italian researchers veered off in another direction: Rue, as a sustainable weed control alternative for corn field weeds such as purslane and pigweed: “Poisonous plants are neglected sources of natural herbicides. An infusion of such a plant rue (Ruta graveolens L.) was tested…rue infusion (100 g/l) and its isolated allelochemicals…open up a promising avenue in the search of natural herbicides.”

Other researchers envision the disease-fighting properties of herbs such as rue and powders such as sodium bicarbonate (baking soda or bicarbonate of soda) being harnessed as alternatives to synthetic fungicides. Indeed, in organic and sustainable conventional farming, rue “at low rates…may lessen the onset of fungicide resistance” against powdery mildew, brown spot and other plant diseases in diverse crops, including strawberries.

Italian researcher Giovanni Aliottal and colleagues in a paper titled “Historical Examples of Allelopathy and Ethnobotany from the Mediterranean Region,” write: “Ruta graveolens L. (Rutaceae), or common rue, originating in Southern Europe, is an evergreen shrub with bluish-green leaves that emits a powerful odour and has a bitter taste. The plant is cited in the ancient herbals and has deep roots in folklore, alchemy and even demonology. Rue has been regarded from the earliest time as successful in warding off contagion and preventing the attacks of fleas and other noxious insects. The name rue derives from the Greek “reuo” (= to set free), because the plant is efficacious in various diseases. Rue was the chief ingredient of the famous antidote to poison used by Mithridates. It was also known to produce erythema and pustular eruptions on human skin. Many remedies containing rue as well as its abortive properties were mentioned by Pliny the Elder in his Naturalis Historia (XX, 143). In Europe, rue was considered a powerful defense against witches during the Middle Ages. Piperno, a Neapolitan physician, in 1625, recommended rue as a treatment for epilepsy and vertigo. Today, the aerial parts of the plant are eaten in Italian salads, and are said to preserve the eyesight. Rue is currently mentioned in the pharmacopoeias of 28 countries where it is considered mainly as a stimulating, antispasmodic, diuretic and emmenagogue. Moreover, fresh and dried leaves are used to preserve and to flavour beverages and foods such as liquor (grappa) and wine, cheese and meat.”

Ruta graveolens is the scientific name for garden rue or herb-of-grace, one of about 1,500 species in the plant family Rutaceae (includes oranges, lemons, other citrus). A native of the Balkans and southeastern Europe grown worldwide, rue is known as sudab or sadab in India, arvada in Tamil, aruda in Singhalese, gedung minggu in Javanese and geruda in Malay. Ruta chalepensis is the scientific name for fringed rue, Aleppo rue or Egyptian rue. Rue researchers D. H. Tejavathil and B. L. Manjula in India summarize: “Ruta graveolens L., a member of Rutaceae, is well known for its wide utilities such as ornamental, aromatic and culinary in addition to medicinal properties. Medicinal value of this taxon is attributed to the accumulation of flavonoids, furanocoumarins, acridine alkaloids, furanoquinolins and also essential oils which led to its recognition as one of the sought after traditional medicinal plants by pharmaceuticals.” Perhaps a bit dangerous, too; according to Egyptian researchers: “On moist skin in direct sunlight, it leads to photosensitivity. The essential oil is a central nervous system depressant and at high doses has become a narcotic.”

A major rue essential oil component, 2-undecanone, is nicely summarized in wikipedia: “2-Undecanone is used in the perfumery and flavoring industries, but because of its strong odor it is primarily used as an insect repellent or animal repellent. Typically, 1–2% concentrations of 2-undecanone are found in dog and cat repellents…” According to its web site claiming “invention” by Dr. R. Michael Roe and referencing 3 patents: “North Carolina State University is currently seeking an industry partner to commercialize a novel, natural insect repellent for mosquitoes, ticks, chiggers, bedbugs, house dust mites, cockroaches, and other pests…A researcher at North Carolina State University has discovered that undecanone and related structures are repellents of mosquitoes, ticks, bed bugs, cockroaches, thrips, aphids, deer flies, gnats and other animals. In some tests, these compounds were found to be more effective than DEET…”

The Flowers of Chania web site provides a nice overview of rue species used as medicine in Crete, grown in Netherlands botanical gardens, and mentioned in Shakespeare’s Hamlet. Unlike the Balkan bean leaf remedy for spearing bed bugs, which has recently sparked the interest of those desperate for bed bug remedies, medicinal plants in the rue family known since ancient times have escaped scientific scrutiny against bed bugs. Probably much to the delight of bed bugs worldwide. According to researchers in India, “The most frequent intentional use of the plant has been for induction of abortion.” If only that powerful rue activity could be integrated to naturally abort bed bug populations just enough to allow humans a more bite-free sleep.

On the Internet are a varied array of commercial products with herbal essential oil and soap (detergent) ingredients sold for potential use against bed bugs (and usually other pests, as well). The herbal ingredients do not need extensive safety testing, as they are GRAS (Generally Recognized as Safe) substances commonly found in foods, cosmetics, etc.

According to the USA FDA (Food and Drug Administration) web site: ““GRAS” is an acronym for the phrase Generally Recognized As Safe. Under sections 201(s) and 409 of the Federal Food, Drug, and Cosmetic Act (the Act), any substance that is intentionally added to food is a food additive, that is subject to premarket review and approval by FDA, unless the substance is generally recognized, among qualified experts, as having been adequately shown to be safe under the conditions of its intended use, or unless the use of the substance is otherwise excluded from the definition of a food additive. Under sections 201(s) and 409 of the Act, and FDA’s implementing regulations in 21 CFR 170.3 and 21 CFR 170.30, the use of a food substance may be GRAS either through scientific procedures or, for a substance used in food before 1958, through experience based on common use in food.”

In other words, if there is a long tradition of eating the stuff and smearing it on your body, it is likely not to need hundreds of millions of dollars and decades of testing and regulatory agency compliance like a pharmaceutical product. So, you don’t have to wait 15 years for a bed bug remedy that will be several times more costly (to recoup the regulatory expenses) than what is already available. Being publicly sold on the Internet, samples of these GRAS pesticide products can often be obtained free of charge by researchers for scientific studies. Sometimes the studies, even if taxpayer or public funded, are published in respected commercial journals and hidden from public perusal behind formidable paywalls. But Internet search engines can usually at least turn up abstracts, media reports and summaries of varying quality and usefulness.

Rutgers researchers compared 11 herbal and detergent products (e.g. Sodium Lauryl Sulfate) and two synthetic pesticide products against bed bugs. A nice summary by the researchers published in an industry trade publication and titled “Natural Pesticides for Bed Bug Control: DO THEY WORK?” was made freely accessible via the Internet. Bed bugs were placed in laboratory chambers offering no escape from spray contact; a valid approach for most product comparisons. But given that many bed bug populations are pesticide resistant and that in real rooms bed bugs hide and avoid spray contact, real world results are usually lower than the lab numbers. These are more or less truisms, for both botanical and synthetic pesticide products. Which is why pest control operators often are called back to spray multiple times over several months or years; and why you need an integrative approach (relying on more than just sprays) and plenty of patience to rid yourself of bed bug infestations. A quick overview of integrative bed bug alternatives with a resource list is found in the Jan. 2015 issue of the IPM Practitioner (as of this writing, still available for free Internet download).

According to the Rutgers researchers, Temprid SC [Imidacloprid (21%) and Beta-Cyfluthrin (10.5%)] killed 100% of exposed adult bed bugs coming in contact with the spray in three days, and “was significantly more effective than Demand CS” [Lambda-Cyhalothrin (9.8%)]. The best herbal formulations were a bit slower: “EcoRaider and Bed Bug Patrol were the most effective biopesticides in both tests. EcoRaider [Geraniol (1%), Cedar Extract (1%) and Sodium Lauryl Sulfate (2%)] caused 100 percent mortality after 10 days in both tests. Bed Bug Patrol [Clove Oil (0.003%), Peppermint Oil (1%) and Sodium Lauryl Sulfate (1.3%] caused an average of 92 percent and 91 percent mortality after 10 days in the first and second experiment, respectively. Neither of these two products caused more than 75 percent mortality at three days after treatment…Bed Bug Bully [Mint Oil (0.25%), Clove Oil (0.3%), Citronella Oil (0.4%) and Rosemary Oil (0.4%)] caused 60 percent mortality after 10 days.”

Thus, the need for a patience and a multi-faceted, integrative approach to bed bug control using herbal or synthetic pesticides, tiny leaf hair-like spikes, CO2, traps, heat, cold, steam, mattress encasements, vacuuming, pheromones, clutter reduction, diatomaceous earth, silica gels, etc. If winning the war against bed bugs were easy, the insects would have been extinct long ago and you would not be reading this.

Termite Power! (Green/Alternative Energy)

February 25, 2015

TERMITE BIOMASS ENERGY conversion offers a potential 95% to 99% efficiency in converting woody plants into usable energy forms comparable to ethanol fuels and petroleum products. “Termites are regarded as harmful because of the ability to decompose cellulosic materials such as houses made of wood,” said University of the Ryukyus (Okinawa, Japan) researchers Toru Matsui, Gaku Tokuda and Naoya Shinzato in the journal Recent Patents on Biotechnology. However, “Termites and/or their symbionts (e.g. gut protozoa & bacteria) are potentially good resource of functional genes for industrial applications…for biomass utilization, environmental remediation, and fine-chemicals production.”

Several termite genes have already been patented for biofuel (cellulase) and fighting infections (antimicrobial peptides). Combinations of cellulase enzymes and anaerobic symbionts have also been harnessed to produce hydrogen fuel (H2 gas) from waste plastics. “Lignin treatment by anaerobic bacteria from the gut of” several termite species has also been patented; thus pointing towards a greener pathway in place of today’s less environmentally-friendly caustic chemical processes. Termite energy production mechanisms might also be released as Open Source scientific information, instead of patented, as was once common in the scientific world. Indeed, the real practical innovations for sustainable world energy production may be in turning the raw material of biological science basic research into economical applied chemical engineering and bio-engineering solutions. In other words, a new energy production landscape dotted with bio-refineries approaching the 95% to 99% energy conversion efficiency of termite guts digesting woody plant and fiber materials is an objective worth working towards.

Being an ancient insect order, termites have been tapping into Earth’s abundant woody plant resources for perhaps 400 million years; well before dinosaurs and then humans roamed and pillaged the planet. “Cellulose is the most abundant biomass on the earth,” write the Ryukyus researchers. “Termites thrive on plant biomass, in which the major constituents are cellulose, hemicellulose (i.e. non-cellulosic carbohydrates), and lignin…In addition, it can be hydrolyzed to give a sugar pool which can be subsequently fermented to form ethanol, etc. However, the crystalline nature of cellulose had made it difficult to economically convert into useful chemical feedstocks…Other than cellulosic materials decomposition, there could be symbionts degrading lignin-derived compounds, a significant part of the wood constituents.”

At the hops-soaked Entomological Society of America (ESA) annual meeting in Portland, Oregon, the parallels between microbrewing (hops & microbes), baking (yeasts; Voodoo donuts) and termite guts as fermentation vats (bio-refineries) producing energy fuels was bubbling just below the surface. Several research labs, including Michael Scharf’s Purdue University lab, are evaluating the genes and metabolic processes innate to termites as well as the contributions of protozoa, bacteria and other microbes living as symbionts in termite guts and helping digest plant lignins and cellulose into usable energy compounds. Figuring out how termites and their gut microbes are such efficient converters of plant matter into energy is a huge undertaking, even with the latest DNA and genetic tools.

Brittany Peterson, an ESA termite biofuel presenter working in Scharf’s lab writes on her web page about “the co-evolution of termites and their over 4,000 symbiotic microorganisms.” The implication being that the termite hindgut is a bio-refinery where termites and their microbial symbionts constitute the equivalent of a vast unknown ecosystem whose parameters are just now being delimited. Peterson and the Scharf lab view termite guts as a model system for studying synergy and biomass processing of tough toxins like lignin. In other words, as the basis and inspiration for designing green bio-refineries for alternative energy and feedstock production processes more energy efficient than turning food crops like corn into ethanol fuel.

Of course, this means figuring out exactly how termites and their several thousand hindgut microbes extract simple sugars from wood’s complex lignin-cellulose polymer structure. This termite/microbe “digestion” (or depolymerization) has an amazing 95%-99% efficiency that industrial biomass processing or biofuel production cannot match even using very toxic caustic chemistries. Most research on termite gut microbes has focused on protozoa, but Peterson envisions adding bacteria and termite-produced enzymes to create a synergistic bio-refinery mixture. In other words, replacing current caustic and energy inefficient biomass conversion chemistries with greener, more energy efficient biological technologies composed of termite-derived enzymes, bacteria and protozoa to depolymerize biomass and produce usable sugars/energy.

The synergy of termite (host) and gut microbes likely makes possible the observed over 95% lignin-cellulose biomass processing efficiency; 82% of the genes for lignin-cellulose processing, including high expression of cellulase enzymes, come from or are innate to the termite itself rather than the symbiotic gut microbes, Peterson told the ESA annual meeting. Though the termite-microbe synergism boosts the the energy efficiency to quite high levels approaching 100%. At least for woody materials.

Interestingly, though, when termites eat paper, most of the biomass processing genes come from the gut microbes. Thus, a quite complex digestive ecosystem that seems to vary greatly with the food (feedstock) input. The gut microbes also help termites detoxify harmful materials and provide antioxidant protection. Scientific bioassays using various combinations of antibiotic drug treatments and anti-protozoa diets are enabling the Scharf lab to construct a microbial “library” for continuing research, Peterson told the ESA. Recent experiments with bacteria isolated from the subterranean termite Reticulitermes flavipes, indicate that the bacteria either alone or via interaction with protozoa boost glucose (sugar; an energy feedstock) release from lignin-cellulose (plant) biomass.

In the future, it is conceivable that bio-refineries using termite enzymes, bacterial enzymes and protozoa will make today’s ethanol and biomass to energy conversion processes look like toxic, inefficient relics of a primitive industrial energy production past. But it will likely be many more years before bio-engineers and chemical engineers are ready to begin the commercial harvest of termite energy to power our vehicles, the Internet, etc.

Termites: Good Medicine (Antibiotic Alternatives)

January 2, 2015

[Note to Search Engines: This is Not Another Termite Poop Story.]
Antibiotic-Resistant Bacteria Beaten by Termite Innate Immune System (the science part)

Antiseptic procedures and germ theory, stuff now routine like doctors and nurses washing their hands to avoid contaminating patients, entered modern medicine via 19th-century applied entomology aimed at solving a mysterious silkworm population decline baffling Italy’s Agostino Bassi and France’s Louis Pasteur (See blog, The Mysteries of Colony Collapse). Today, Pasteur might be looking over the shoulder of Yuan Zeng in Xing Ping Hu’s Urban Entomology Lab at Auburn University, wondering how termites make themselves more robust and immune to disease. After working with silkworms and formulating modern germ theory, Pasteur realized that “the exclusive emphasis on the germ theory of contagious disease” was a very incomplete view of reality in need of modification; a radical notion that would be opposed by many in modern medicine even today, as germ theory has attained the status of orthodoxy and relegated the alternatives to the fringes.

Pasteur told colleagues that if he had the chance to go back to silkworm entomology again he would focus on nutrition, the environment and physiology (e.g. immunity) to increase robustness, vigor and disease resistance. Stuff that would be cutting edge in the 21st century. Stuff like termite entomologist Yuan Zeng’s study of how termite “innate immune systems” overcome MultiDrug Resistant (MDR) bacteria infecting over 2 million people annually in the USA. MDR bacteria in the USA annually kill over 23,000 “because they are untreatable with today’s drugs,” Zeng told the Entomological Society of America (ESA) annual meeting. MDR bacteria are also becoming “a significant global health threat.” An excellent YouTube video of Yuan Zeng describing her Auburn University research on termites defeating MDR bacteria is now available.

Zeng’s previous research with powdered extracts of Eastern subterranean termites (Reticulitermes flavipes) against bacteria causing human gastric distress lends credibility to traditional folk medicines containing insects. “Our previous research on disease resistance in R. flavipes workers showed that the crude extract of naive termites constitutively displayed a broad-spectrum antibacterial activity including agents responsible for human gastric infections,” Zeng told the ESA annual meeting. The logic behind using termites as medicines or drugs is that subterranean termites forage and nest in soil loaded with pathogenic microbes, making them a “source for novel antimicrobial discovery because they have evolved effective innate immune systems in confronting various harmful microorganisms.”

If a termite species is both pest and medical cure, then might an alternative to chemical fumigation be to harvest (e.g. trap or vacuum) the termites and sell them as a medicinal crop? That is a question that rarely, if ever, is asked. “Science has already proven the existence of immunological, analgesic, antibacterial, diuretic, anesthetic, and antirheumatic properties in the bodies of insects,” wrote Brazilian researcher Eraldo Medeiros Costa-Neto in an article titled ENTOMOTHERAPY OR THE MEDICINAL USE OF INSECTS. “Since early times, insects and the substances extracted from them have been used as therapeutic resources in the medical systems of many cultures. Commonly considered to be disgusting and filthy animals, many insect species have been used live, cooked, ground, in infusions, in plasters, in salves, and as ointments, both in curative and preventive medicines.”

Florida is the place where all the termites of the world seem to be coming to live. The Palm Beach, Florida, TV news recently warned of a Caribbean invasion of conehead or tree termites, known scientifically as Nasutitermes corniger. Conehead termites avoid competing with subterranean termites by building “beach-ball size” nests above ground and “brown tubes up the outside walls of houses,” and according to the TV make wood look like “shredded wheat.” Even “aggressive spraying” dating back to 2001 failed in its goal of eradication, and 100 million conehead termites nesting in 120 colonies amongst 42 properties were sprayed in 2012. Conehead termites, which are “distributed from southern Mexico to northern Argentina and the West Indies,” are “commonly used in traditional medicine in Northeast Brazil,” say scientists in Brazil. No doubt the coneheads will turn up again and again in Florida until they are finally accepted as residents. That is the nature of invasive insects.

Perhaps instead of chemical eradication programs, these termites should be harvested and exported to Brazil and elsewhere for medical use. “With the increase in microbial resistance to antibiotics, the use of natural products represent an interesting alternative for treatment,” wrote Henrique Coutinho and his Brazilian colleagues in an article titled “Termite usage associated with antibiotic therapy.” Crushed and powdered conehead termites mixed with a conventional antibiotic drug (which was failing, due to bacterial resistance) produced “a new weapon against the bacterial resistance to antibiotics” via a termite-drug synergy. In other words, mixing powered conehead termites with the drug made for a more powerful antibiotic medicine than using the antibiotic drug alone. At least the coneheads are good for something.

Yuan Zeng told the ESA and YouTube that she fed subterranean termites “sublethal concentrations of MultiDrug Resistant (MDR) pathogens, Methicillin-resistant Staphylococcus aureus (MRSA) or Pseudomonas aeruginosa (PAOl),” which induced “an alternation of protective proteins” produced by the termite’s innate immune system. “The composition changes of proteins following the feeding of MDRs significantly inhibited the growth of P. aeruginosa and MRSA,” said Zeng. “The results of this research could be a significant breakthrough for developing novel effective drugs” to fight human disease pathogens resistant to multiple antibiotic drugs. Worldwide, millions of people stand to benefit.

Known termite immune proteins include termicin, spinigerin, lysozome, tGNBPs, and “two unidentified proteins from several termite species with potent antibacterial and antifungal activities.” However, Zeng’s termite antimicrobial compounds are different; though there is still much scientific work to be done.

In the journal “Recent Patents on Biotechnology,” Japanese researchers Toru Matsui, Gaku Tokuda and Naoya Shinzato from University of the Ryukyus in Okinawa discussed patenting termite genes for alternative energy and drug production. “Although termites are regarded as harmful because of the ability to decompose cellulosic materials such as houses made of wood,” said Matsui et al. “Termites and/or their symbionts are potentially good resource of functional genes for industrial applications…for biomass utilization, environmental remediation, and fine-chemicals production.” Several termite genes have already been patented for biofuel (cellulase) and fighting infections (antimicrobial peptides).

A fungus-growing termite, Pseudacanthotermes spiniger, is notable for producing termicin, an antifugal peptide, and spinigerin, an anti-bacterial and antifungal peptide. “These peptides and the corresponding cDNAs have been patented as useful for protection of plants from pathogenic fungi or medical purposes,” said Matsui et al. “Similarly, some chemical antibiotic compounds isolated from termites have also been patented for the use of treating a microbial infection or disease.”

“Although entomotherapy is an ancient practice, it is still relatively unknown in the academic world,” wrote Costa-Neto. “In fact, as Holt already stressed in 1885, the advance of medical science and the suppression of folk knowledge swept away belief in the medicinal qualities of insects.”

Insect species outnumber plant species 16-fold, according to an article in The Indian Journal of Traditional Knowledge: “Yet very few researchers have concentrated on the medically useful properties of insects. Most research with insects revolves around getting rid of them.”

Medical Botany refers to plants used for medical or health purposes. But there is no entomological equivalent. Medical Entomology addresses arthropods as medical or pest problems; and by analogy is like Weed Science to Botany. Insects as medicinal cures or health enhancers are outliers, orphan science, folk healing curiosities; perhaps supermarket tabloid fodder alongside celebrity scandals and UFO abductions.

In South India winged subterranean termites (Odontotermes formosanus) are traditionally roasted in earthen pots and consumed for three evenings to treat asthma. But their anti-bacterial qualities have not been explored, “mainly because of the difficulty in harvesting large numbers.” Memo to South India: An abundance of potentially medicinal subterranean termites are ready for harvesting and roasting for export in south Florida, Hawaii, New Orleans, Auburn, Mississippi, etc. Perhaps in some distant future a doctor will say, “Take two powdered termites and some Vitamin C, and call me in the morning.”


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