Application of central composite rotatable design to lipase catalysed synthesis of m-cresyl acetate.

Manohar, B. and Divakar, S. (2002) Application of central composite rotatable design to lipase catalysed synthesis of m-cresyl acetate. World Journal of Microbiology and Biotechnology, 18 (8). pp. 745-751.

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Abstract

Esterification of m-cresol with acetic acid using porcine pancreas lipase (PPL) was investigated by response surface methodology (RSM). A central composite rotatable design (CCRD) involving 32 experiments of five variables at five levels was employed to analyse the esterification behaviour. The effect of five variables studied namely, m-cresol concentrations (0.005–0.025 mol), enzyme/substrate ratios (0.18–1.22 activity units/millimol, AU/mmol), incubation periods (6–54 h), pH (4–8) and buffer volumes (0–0.2 ml) was useful in arriving at an optimum ester yield. The methodology projected conditions for higher yields up to 6.0 mmol. Validation experiments carried out under these predicated conditions showed good correspondence between experimental and predicted yields. CCRD treatment clearly showed the inhibitory nature of m-cresol in the esterification process. The reaction required the presence of buffer for better conversions and a minimum amount of 0.1 ml buffer was found necessary for this reaction. Buffer pH values around 6.0 and below appeared to favour better esterification than those at pH values in the range 6.0– 8.0. However an optimum condition for maximum yield was: incubation period: 54 h; buffer volume: 0.2 ml; pH: 8; E/S ratio: 0.83 AU/mmol; m-cresol: 0.02 mol; predicted yield: 6.0 mmol; experimental yield: 6.4 mmol.

Item Type:	Article
Uncontrolled Keywords:	Buffer; Enzyme/substrate ratio; Esterification; Optimization; pH; Response surface methodology
Subjects:	500 Natural Sciences and Mathematics > 04 Chemistry and Allied Sciences > 16 Enzyme Chemistry
Divisions:	Fermentation Technology and Bioengineering
Depositing User:	Somashekar K.S
Date Deposited:	16 Jun 2011 11:15
Last Modified:	28 Dec 2011 09:42
URI:	http://ir.cftri.res.in/id/eprint/3063

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