APPLICATION OF RESPONSE SURFACE METHODOLOGY (RSM) TO ENHANCE MCLPHA COPOLYMER PRODUCTION BY MASSILIA SP USING CANE MOLASSES AS A CARBON SOURCE

Abstract

Cane molasses is an inexpensive, sustainable by-product of the sugar industry, which supports the growth of
microorganisms as it contains several growth factors. Response Surface Methodology (RSM) employing central
composite design (CCD) was applied to enhance PHA production by Massilia sp at shake flask level by using molasses as a
carbon source. Isolate produced maximum DCW (54.0 g/l) and PHA (3.0 g/l) when medium was optimized with the
help of CCD. Optimized concentration of medium components to maximize PHA production was found to be as
follows: molasses: 100.0 g/l, NH4HPO4
: 1.67g/l, Na2HPO4
: 5.86g/l, K2HPO4
: 5.74g/l, MgSO4
: 0.25g/l, trace
element solution: 0.1ml/l. The point optimization method reported a small difference of 0.02g/l, indicating the validity
of mathematical models developed after applying CCD.