28 Recent Patents on Biotechnology 2009, 3, 28-36 1872-2083/09 $100.00+.00 © 2009 Bentham Science Publishers Ltd. Biopesticide Production from Bacillus thuringiensis: An Environmentally Friendly Alternative Ninfa M. Rosas-García* Laboratorio de Biotecnología Ambiental. Centro de Biotecnología Genómica-IPN. Blvd. del Maestro s/n. Reynosa, Tamp. CP 88710 México Received: October 29, 2008; Accepted: November 26, 2008; Revised: November 28, 2008 Abstract: Since its discovery as a microbial insecticide, Bacillus thuringiensis has been widely used to control insect pests important in agriculture, forestry, and medicine. The wide variety of formulations based on spore-crystal complexes intended for ingestion by target insects, are the result of many years of research. The development of a great variety of matrices for support of the spore-crystal complex enables many improvements, such as an increase in toxic activity, higher palatability to insects, or longer shelf lives. These matrices use many chemical, vegetable or animal compounds to foster contact between crystals and insect midguts, without harming humans or the environment. Biotechnology companies are tasked with the production of these kinds of bioinsecticides. These companies must not only provide formulations tailored to specific crops and the insect pests, but they must also search for and produce bioinsecticides based on new strains of high potency, whether wild or genetically improved. It is expected that new products will appear on the market soon, providing an increased activity spectrum and applicability to many other pest- impacted crops. These products may help develop a more organic agriculture. This review article discusses recent patents related to bioinsecticides. Keywords: Bioinsecticides, formulations, insect pests, biological control, encapsulation, polymers, matrices, insecticidal preparations, delta-endotoxin, cry genes, insecticidal crystal, toxic activity, lepidopterans, coleopterans, dipterans. INTRODUCTION The bacterium Bacillus thuringiensis was discovered by Shigetane Ishiwata in 1901 [1], and rediscovered by Berliner ten years later. The bacterium was isolated from diseased larvae of Anagasta kuehniella, and this finding led to the establishment of B. thuringiensis as microbial insecticide. The first record of its application to control insects was in Hungary at the end of 1920, and in Yugoslavia at the beginning of 1930s, it was applied to control the European corn borer [2]. During the following two decades, several field tests were conducted to evaluate its effectiveness against lepidopterans, both in Europe and in the United States [3], and results favored the development of formulations against on this pathogen. Subsequently, the first commercial product was produced in 1938 by Libec in France. [4]. Unfortunately, the product was used only for a very short time, due to World War II [5]. After World War II, the Green Revolution provided great agricultural advantages via the use of agrochemicals, chemi- cal fertilizers, highly productive cultivars, and mechani- zation. The result was a considerable decrease in a great variety of insect populations, and as a consequence, synthetic insecticidal compounds became popular due to the long residual action and the wide toxicity spectrum. However, fully synthetic chemical insecticides appeared in 1940, when organochlorinated and organophosphate insecticides were discovered. These insecticides were applied during all *Address correspondence to this author at the Laboratorio de Biotecnología Ambiental. Centro de Biotecnología Genómica-IPN. Blvd. del Maestro s/n. Reynosa, Tamp. CP 88710 México; Tel: 52-899-924-3627; Ext: 7721; Fax: 52-899-925-2889; E-mail: nrosas@ipn.mx; ninfarosasg@yahoo.com.mx growing seasons to attack all the developmental stages of insect pests [6]. The indiscriminate use of these compounds caused, by 1950, a resurgence of pests, due to the elimination of their natural enemies and the appearance of pest populations showing resistance to insecticides. Also serious environmental and health issues began to be recognized by the presence of chemical residues in food, water, and air. To counteract this contamination, attention and efforts were directed to the use of biological control agents including insect pathogens [7]. However, an entomopathogenic organism must fulfill several requisites before being released to the environment as a potential control agent. It should be highly specific and effective against the target pest. The organism should demonstrate the potential to be successfully processed by continuous production technology. The control agent should be available in formulations with a reasonable shelf life, should be stable, and should be harmless to human and non-target flora and fauna [8]. As an entomopathogenic organism, B. thuringiensis fulfills all these requirements. Bacillus thuringiensis is a gram-positive spore-forming bacterium that produces crystalline proteins called delta- endotoxins during its stationary phase of growth [9]. The crystal is released to the environment after lysis of the cell wall at the end of sporulation, and it can account for 20 to 30% of the dry weight of the sporulated cells [9] Fig. (1). This bacterium is distributed worldwide. The soil has been described as its main habitat; however it has also been isolated from foliage, water, storage grains, and dead insects, etc. Isolation of strains from dead insects has been the main source for commercially used varieties, which include