|Kuo, Tsung Min|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/8/2004
Publication Date: N/A
Technical Abstract: Pseudomonas aeruginosa NRRL B-18602 was previously found to convert ricinoleic acid (RA) in small shake flasks to 7,10,12-trihydroxy-8(E)-octadecenoic acid (7,10,12-THOD), which inhibited fungal growth especially active against the rice blast fungus. Conversion of RA was examined for sixteen strains of P. aeruginosa including the patented NRRL B-18602, three recent isolates from composted materials, and twelve isolates obtained randomly from the ARS Culture Collection. Strains NRRL B-1000 and NRRL B-23260 were the best 7,10,12-THOD producers. The bioconversion was carried out in a 2-L reactor using crude RA prepared from saponification of castor oil and strain NRRL B-23260 to produce 7,10,12-THOD in sufficient quantities for testing of industrial uses and to determine its properties for new uses. The reactor process employed a unique aeration mechanism that involved a filtered airflow constantly supplied from the top through two ports on the headplate and, when needed, at varied rates as regulated through a bottom sparger. The production yield was 27% after 60 h of reaction. 7,10,12-THOD was crystallized from ethyl acetate extracts of the reactor broth following a sequential cooling process to about -20 deg C. 7,10,12-THOD, which had a melting point of 94.5-95.0 deg C, was found to exhibit a unique surface-active property. This study has provided basic information useful for further developing production processes suitable for commercial uses of 7,10,12-THOD.