Isolation and characterization of pesticide degrading bacteria acinetobacter baumannii a85 from the micro-niche of oryza sativa l. and its antioxidant activity

Pesticide degradation is one of the major problems facing today which contaminate the environment. Microorganisms are most commonly used in the biodegradation of pesticides. The present study is focussed on the isolation and characterization of pesticide degrading bacterial strain from the micro niche of rice grains by 16srRNA gene sequencing, using colony PCR. The bacteria were isolated from the micro niche of rice grains using 50 ml of MSM medium, with 200mgl-1 of canistan and 200 mgl-1of 20 % flubendiamide (diamide pesticide) and the cultures were maintained by suspending pure single colonies in nutrient agar broth. Morphological characterization of isolated strain was done by Gram staining and found that were pink coloured, aerobic and gram negative cocco-bacilli. The preliminary identification and characterization of isolated bacteria under study were done by using VITEK 2 machine, which read the isolated bacteria as Acinetobacter baumannii. Using colony PCR amplification of 16S rRNA gene sequence of Acinetobacter baumannii was done in order to confirm the bacterial strain with the help of BLAST search tool. The isolated bacterial strain, Acinetobacter baumannii was checked for the biodegradation of pesticides at different concentration, i.e., 0.5 mg/ml, 1.0 mg/ml, 1.5 mg/ml, 2.0 mg/ml and 2.5 mg/ml. The maximum growth occurred in MSM medium with 2.0 mg/ml 20% of flubendiamide. Theisolated bacterial strain is also showed antioxidant property. It was observed that cell free extract of Acinetobacter baumannii A85 have highest inhibitory action at 72 hour culture.