The Development of Abamectin in China
Abamectin is a sixteen-membered macrolides compound with insecticidal, acaricidal and nematicidal activity, as well as a metabolite extracted from streptomyces griseus of streptomyces through liquid fermentation. Abamectin is new antibiotic bio-pesticide with a variety of features such as high efficiency, low toxicity, low residue, novel structure and dual-use of crops and livestock, so its development and application are considered as another great contribution of antibiotics on human after penicillin from the world’s biological circle.
With improvement of people’s living standards and pursuit for green food, bio-pesticides are popular with current pesticide market. According to reports, sales of European bio-pesticides have increased from $100 million in 1997 to $169 million in 2004, with usage accounted for 20% all over the world. In addition, North America accounted for 44%, while Asia accounted for 13%, Oceania accounted for 11%, Latin America and the Caribbean accounted for 9%, Africa accounted for 3%. The world’s bio-pesticides will enter a broad development stage. Pundits predicted that the 21st century will be the century of biological pesticides, and abamectin insecticide has become the most popular new products with highly competitive in the current bio-pesticide market.
Original drug of abamectin is white or yellow crystal, with vapor pressure less than 200nPa and melting point within 150~155°C. At the temperature of 21°C, its solubility is 7.8 micrograms per liter in water, while 100 grams per liter in acetone, 350 grams per liter in toluene, and 70 grams per liter in isopropanol as well as 25 grams per liter in chloroform. Besides, it is not easy to decompose at room temperature. And there is no decomposition phenomenon in the solution with PH value of 5~9 at the temperature of 25°C.
In 1995, China just started producing abamectin, with the export price up to around 30,000 yuan per kilogram. In 1996, abamectin came into the Chinese market, and the price is as high as 26,000 yuan per kilogram. The price experienced a slight decline in 1997 and 1998, while quickly dropped to 3,000 yuan per kilogram later. But the price was still able to make business profitable until 2000. In 2001, prices had fallen sharply with a decrease up to 30%, and even fell to 1,000~1,200 yuan per kilogram in 2002. In 2003, American production base suspended production in the third world, at the same time, abamectin was widely used for large area agricultural pest control in vegetables, fruit, cotton, rice and forest, resulting in dosage of abamectin increasing significantly, especially production costs gradually reduce with the abamectin processing technology mature day by day, these reasons allowed China to be the largest producer and exporter of abamectin as well as its products were exported to Britain, France, the United States, South America and other countries and regions. On December 31, 2003, 320 kinds of pesticides including insecticides, fungicides and herbicides had been banned from selling in the EU market for the EU’s pesticide ban, and had involved the import of agricultural products containing residues of the chemical composition. And as a major bio-pesticide currently, the demand for abamectin exceeded the supply, which led directly to abamectin price increasing from about 900 yuan per kilogram to around 2,400 yuan per kilogram in the first half of 2004.
Abamectin is in a great boom in 2004. But due to certain vicious cycle laws in current pesticide market, as well as unreasonable production and marketing structure and balance between supply and demand in 2005, abamectin entered into large-scale development phase. According to reports, American companies produced abamectin with fermentation unit about 8,000~10,000 micrograms per milliliter, while Chinese manufacturers generally produced abamectin with fermentation unit of 3,000~4,000 micrograms per milliliter. However, according to recent reports, Chinese scientists have screened out the high-yielding, stable production strains through advanced breeding methods, optimizing technology and unique mutation measures, which have made abamectin fermentation titer up to 8,400 micrograms per milliliter and maintained at more than 8,100 micrograms per milliliter.