Biotransformasi Asid Oleik oleh Pseudomonas sp. strain SS22

Pseudomonas sp. strain SS22 was isolated from an oxidation pond of a palmoil mill in Malaysia. In this study, the ability of this bacterium to transform oleic acid to new products was investigated. The biotransformation products were analyzed by thin layer chromatography (TLc), gas chromatography (Gc), fourier transform infrared spectroscopy (FTlR) and gas chromatography-mass spectrometry (GC-MS). TLC analysis showed that only one new product was formed after 7 days incubation at 37°C, shaken at 150 rpm. Further incubation resulted in the reduction ofthe product spots on the fourteen days. GC analysis showed that 5 new product peaks at retention times 13.1(*A), 15.0 (*C), 15.3 (*D), 16.8 (*E) and 18.4 (*F) minutes were formed after 7 days incubation. The lR spectrum ofproducts formed from oleic acid after 7 days, showed the presence of OH/NH stretch at 3417 cm^-1. Absorption at 2673 cm·! may possibly be due to CH stretch together with carbonyl group. An absorption at 1712 cm^-1 was also consistent with the c=o stretch of ketone or carboxylic acid. The CH stretch at 2932, 2854, 1462 dan 1379 cm-I belonged to alkyl group, indicative of hydrocarbon products also occurring in the products mixture. The presence of CH/C-C absorption at 969 dan 725 cm^-1, indicative of the presence oftrans alkene (C=C). GC-MS analysis confirmed that the product was a mixture of 9(E)-hexadecenoic acid, caprilic acid, myristic acid and hydrocarbons. Although the products formed were mixtures, 9(E)-hexadecenoic acid could be use as components of their membranes lipid. The yield of the products could be improved by optimizing the growth condition.