Pesticides, natural

These substances include as high a percentage of compounds which are carcinogenic as among the synthetic pesticides. It has been estimated for the USA (the conditions in Europe should be similar) that the population consumes with food on average 1500 mg per person and day of natural pesticides, but only 0.09 mg of synthetic pesticides. In summary, it can be concluded that a risk of impairment of consumer health is not discernible in the case of the proper and controlled application of registered PPA. 

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Supercritical fluid extraction (SFE) has been widely used to the extraction processes in pharmaceutical industries. Besides application of SFE in phannaceuticals, it has been applied on a wide spectmm of natural products and food industries such as natural pesticides, antioxidants, vegetable oil, flavors, perfumes and etc [1-2]. 

Unfortunately, nicandrenone is typical of many instances in the field of natural pesticides where elucidation of chemical structure has not previously received the attention it deserves. However, with the increased availability of powerful instrumental techniques, considerable progress has been made during the past decade. Since the last general review (14), active principles from several more of the time-honored insecticidal plants have yielded to structure elucidation (Table I). 

Einhellig, F.A. "Allelopathy - A Natural Protection, Allelo-chemicals," in "Handbook on Natural Pesticides Methods,... 

Local certification has a number of advantages, not least that it is one way to reduce costs to producers in developing countries via locally determined fees reflecting local incomes (Barrett et al., 2001). To be accepted by the European Union (EU), local certification bodies are required to demonstrate that their standards of organic production and inspection are equivalent to EU regulations. The standards need not necessarily be identical, however, and as such this means more locally appropriate standards can be set in place. For example, local certification bodies may well allow the use of such natural pesticides that would not normally be allowed under EU Standards (Myers, 2000). 

Roshchina VV (2005 c). Biosensors for the study of allelopathic mechanisms and testing of natural pesticides. In Proceedings of International Workshop on Protocols and Methodologies in Allelopathy, April 2-4, 2004 Palampur. (Eds. G.L. Bansal and S.P.Sharma). Pp. 75-87. College of Basic Sciences, Palampur, India. 

Natural pesticides show promise for alleviating the pollution problem. Plants make some of these pesticides for their own protection, and bacteria synthesize others for purposes that are poorly understood. In spite of their promise, however, products based on natural pesticides have been on the market for years without much success, their major drawbacks being high cost and a reputation for unreliability. The present hope is that continuing research can... 

Chapman, P.J. An outline of reaction sequences used for the bacterial degradation of phenolic compounds, in Degradation of Synthetic Organic Molecules in the Biosphere Natural Pesticidal, and Various Other Man-Made Compounds (Washington, DC National Academy of Sciences, 1972), pp. 17-55. 

On the other hand, the assumption that substances permitted as natural pesticides by the organic farming standards are harmless to non-target animals and humans still has to be proven. An urgent call for further investigation exists as recent studies of Neem (Azadirachta indicd) extracts, for example, demonstrated their harmful potential by affecting abortion pregnancy of rats, baboons and monkeys (Talwar et al. 1997). 

Dowd, P. F. In Natural Pesticides Volume V Insect Attractants and Repellents Morgan, E. D. Mandava, L. B. Eds. CBC Press Boca Raton, in press. 

Mandava,B. CRC Handbook of Natural Pesticides CRC Press Boca Raton, 1985 p. 552. 

There are a few companies that are hoping to change this. Several chemical companies that already have a large share of the chemical pesticide market are actively screening fermentation broths. A major motivation for this probably comes from the present concern about our environment. There is a perception that "natural pesticides will have a much less serious environmental impact than "chemicals". Whether this advantage is real or only psychological remains to be seen. 

Jacobson, M. In "Natural Pesticides from the Neem Tree (Azadirachta Indica A. Juss.)" Schmutterer, H. Ascher, K.R.S. Rembold, H., Eds. German Agency for Technical Cooperation Eschborn, Germany, 1980 pp. 33-42,... 

Methods by which to find a biologically active compound may be classified as (a) random selection/screening (b) directed synthesis (c) natural product models and (d) biorational design. Allelochemical research can be considered as a natural product model. Generally, natural pesticides such as allelochemicals can be the biological compound(s) itself or products or parts of plant tissues. 

Structural and Genetic Variation of Natural Pesticides in Pigment Glands of Cotton (Gossypium)... 

Caffeine Caffeine [l,3,7-trimethyl-l//-purine-2,6(3/7,7//)-dione], molecular formula C8H10N4O2, is a xanthine (purine) alkaloid, found mainly in tea leaves Camellia sinensis) and coffee beans (Coffea arabica). Caffeine is sometimes called guaranine when found in guarana (Paullinia cupana), mateine when found in mate (Ilex paraguariensis) and theine when found in tea. Caffeine is found in a number of other plants, where it acts as a natural pesticide. It is odourless white needles or powder. Apart from its presence in the tea and coffee that we drink regularly, caffeine is also an ingredient of a number of soft drinks. 

About 99.9 percent of the chemicals humans ingest are natural, and the amounts of synthetic pesticide residues in foods are insignificant compared to the amount of natural pesticides that are always in our diet because of the plants we eat.13 Of all dietary pesticides that humans eat, 99.99 percent are natural chemicals produced by plants to defend themselves against fungi, insects, and other animal predators. The natural pesticides come in great variety because each plant produces a different array of such chemicals. 

Only a small proportion of natural pesticides have been tested for carcinogenicity, but 38 of the 72 tested are rodent carcinogens. As shown in Table 2, naturally occurring pesticides that are rodent carcinogens are ubiquitous in common fruits, vegetables, herbs, and spices. The widespread distribution of such chemicals means that no diet can be free of natural chemicals that are rodent carcinogens. 

Table 2. Carcinogenicity Status of Natural Pesticides Tested in Rodents...

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