Sri Kumalaningsih, Nur Hidayat and Nur Aini
Study to obtain the optimum condition for the production of PHAs by Alcaligenes latus was carried using liquid bean curd waste as low cost carbon source. A Response surface method with two factors i.e. the initial sucrose concentration (15 g/L, 20 g/L, and 25 g/L) and time of incubation (48 hours, 60 hours, and 72 hours) was employed. The yield was taken after the inoculation A. latus on to the liquid bean curd waste. The results obtained from the study are computed with Design expert 7.1.3. The optimum condition found were the initial sucrose concentration of 25 gr/l and time of incubation of 60 hours 18 minute which producing 2.48 gr/l PHA and the dry cell concentration was 66.56%. The functional group of the PHA granule was identified as C=O by Fourier transforms infrared (FTIR).
Key words: Polyhydroxyalkanoates, liquid bean curd waste, Alcaligenes latus, carbon source, FTIR