Isolation and identification of a newly isolated lipase-producing bacteria (Acinetobacter baumannii RMUTT3S8-2) from oily wastewater treatment pond in a poultry processing factory and its optimum lipase production

Abstract

This research aimed to optimize the cultural conditions of a newly isolated RMUTT3S8-2 from oily wastewater treatment pond in a poultry processing factory to enhance its lipase production. The isolated RMUTT3S8-2 was molecularly identified as Acinetobacter baumannii. Lipase production was optimized using Plackett-Burman Design and Box-Behnken Design. The important variables were investigated and chosen as peptone, 24.49 g/L; yeast extract, 33.82 g/L and NaCl, 6.21 g/L. In optimized conditions, the lipase activity of A. baumannii RMUTT3S8-2 was 216.23 ± 3.69 U/mL, more than unoptimized condition by 2.2 times. Lipase stability was above 95 % in the pH range of 5.0 to 9.0 at 30 °C. In addition, A. baumannii RMUTT3S8-2 could digest the oil in poultry processing wastewater and exhibited the degree of oil hydrolysis of 41.94 ± 4.98 % at 12 days. This newly isolated A. baumannii RMUTT3S8-2 showed promise as a lipase producer, especially for oily wastewater treatment.