All the experiments were carried out under a nitrogen stream on capped vials. The anaerobic conditions were maintained with a disposable anaerobic indicator (Gas Pac Becton Dickinson Co., Orangeburg, NY). The incubations were carried out at 37 OC , and 4,8,16,24,72 h after the addition of the corresponding BA, the reaction was stopped with addition of 150 pL of a 30% solution of KOH. Tubes were centrifuged at 3500 rpm for 10 min, and 2 mL of the ...