|Kuo, Tsung Min|
Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: May 12, 1999
Publication Date: N/A
Technical Abstract: Six strains of Sphingobacterium thalpophilum (NRRL B-23206, NRRL B- 23208, NRRL B-23209, NRRL B-23210, NRRL B-23211, and NRRL B-23212) were isolated from a compost mixture that was enriched with soybean oil outdoors and subsequently with oleic acid in the laboratory. All these strains converted oleic acid predominantly to 10-ketostearic acid (10- KSA; 87-94% of the total conversion product) with small amounts of 10- hydroxystearic acid (10-HSA; 6-13%) also present. This is in contrast to Sphingobacterium thalpophilum strain B-14797, which was previously found to produce solely 10-HSA. When ricinoleic acid was used as substrate, only strain NRRL B-23212 yielded conversion products which were short-chained fatty acids. Strain NRRL B-23210 was further characterized for the conversion of oleic acid. While the maximum cell growth was reached at about 24 h, the maximum conversion was reached at about 36 h after the addition of oleic acid to the fermentation broth. The optimum pH for the bioconversion was 7.0-8.5 with a yield of greater than 75% at 28C and 200 rpm. This is the first report on the conversion of oleic acid to 10-KSA by microorganisms in the genus Sphingobacterium.