Collection of endemic actinomycetes capable of degrading Lindane in order to produce biological products for the treatment of pesticide pollution toward safe agricultural production

Abstract

Pesticide residues in the soil are a huge threat to agriculture. ɤ- hexachlorocyclohexan (Lindane or isomer ɤ -HCH) is one of the pesticides widely used in agriculture after 1945. Due to the harmful effects on health of Lindane, UNEP (United Nations Environment) Program - United Nations Environment Program) decided to stop the pollution of Lindane worldwide in 2005. However, with a long half-life, it is very difficult to control residual Lindane in soils. The purpose of this study is to isolate and select actinomycete strains capable of degrading Lindane in order to develop a biological product that can remove residual Lindane in agricultural soil in a safe and environmental-friendly manner. Basic actinomycete isolation methods have been applied in combination with a number of oriented isolation methods to evaluate the growth ability of actinomycetes on media with and without Lindane. The ability to degrade Lindane of actinomycetes was also evaluated based on the rate of chloride ion removal in the substrate. The remarkable actinomycetes were then studied for biological characteristics such as morphology, biochemical and physiological properties, and some metabolic activities related to the degradation of Lindane. We obtained 9 actinomycetes capable of decomposing Lindane isolated from soil samples in farms in Nghe An. Among them, the two strains A119 and LD02 belonging to the genus Streptomyces displayed the best Lindane degradation performance based on their chloride ion removals. They were further studied for their biological characteristics and eventually identified.