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An esterase activity from Terfezia claveryi Chatin ascocarps, a mycorrhizal hypogeous fungus, is described for the first time. The enzyme was partially purified using phase partitioning in Triton X-114 (TX-114), achieving a reduction of 87% in the triglyceride content and the removal of 63% of phenols. The enzyme showed maximum activity toward short-chain p-nitrophenyl esters, and no interfacial activation was observed, indicating that the enzyme responsible for this activity is an esterase and not a lipase. This esterase presented its maximum activity at pH 7.4 and 60 degrees C. The values obtained for Km at pH 7.4 were 0.3 mM for p-nitrophenyl butyrate and 0.6 mM for p-nitrophenyl acetate with catalytic efficiencies (Vmax/Km) of 0.23 and 0.32, respectively. T. claveryi esterase was inhibited by phenylboric acid, indicating that serine residues were involved in the enzyme activity. This activity was localized only in the hypothecium and was absent from the peridium and gleba.

In the present paper, a novel enzymatic reaction between (R,S)-O-butyryl propranolol (O-BP) and lipase from Candida rugosa in the presence of hydroxypropyl-beta-cyclodextrin (HP-beta-CD) is described. Under the used condition, lipase catalyzed the intramolecular transacylation of O-BP into N-butyryl propranolol (N-BP). Propranolol, the product of the expected hydrolysis reaction, was not detected in the reaction medium. A chiral analysis of the reaction product indicated that lipase showed a preference for (R)-O-butyryl propranolol since it first transformed the (R)-enantiomer and then the corresponding (S)-enantiomer. The influence of different reaction conditions on the initial rate is also studied.