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Screening 27 commercial lipases showed that enzymes from Candidu cylindracea, Pseudomonas fluorescens and Mucor miehei (immobilized) promoted synthesis of selected low molecular weight esters in nonaqueous systems. Maximum production after 24 hr incubation was obtained with substrate concentrations of 0.05 mol/L for isopentyl acetate, 0.2 mol/L for ethyl butyrate and 0.3 moliL for isopentyl butyrate. Yield of butyl butryate was almost 100% at acid substrate greater than 0.2 mol/L. Substrate inhibition was observed with J'. fluorescens lipase but not with C. cylindrucea or M. miehei lipases, up to 1 mol/L. Hexane, octane and decane could be used as reaction media except for ethyl butyrate synthesis where hexanc was the medium of choice. Poor synthesis was achieved when methylene chloride was used.

Mixtures of Car C, and C, chain length aliphatic alcohols found in fuse1 oil were converted to their acetic acid and butyric acid esters using a lipase (from Candidu cylindrucea) mediated process in a water immiscible fluid (hexane). Incubation temperature was 30°C with shaking (150 rpm). Maximum production of the mixed butyric acid ester product (0.62 mol/L; yield = 65.8%) and acetic acid ester product (0.052 mom; yield =46.4%) were obtained in 48 hr. Enzyme could be reused three times before loss of activity for acetic acid ester synthesis but enzyme activity decreased after one use for butyric acid ester synthesis.

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