Factors influencing the production of a novel compound, 7,10-dihydroxy-8(E)-octadecenoic acid, by Pseudomonas aeruginosa PR3 (NRRL B-18602) in batch cultures.
Pseudomonas aeruginosa PR3 (NRRL B-18602) converts oleic acid to a novel compound, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD). Parameters that included medium volume, cell growth time, gyration speed, pH, substrate concentration, and dissolved oxygen concentration were evaluated for a scale-up production of DOD in batch cultures using Fernbach flasks and a bench-top bioreactor. Maximum production of about 2 g DOD (38% yield) was attained in Fernbach flasks containing 500 ml medium when cells were grown at 28 degrees C and 300 rpm for 16-20 h and the culture was adjusted to pH 7 prior to substrate addition. Increases of medium volume and substrate concentration failed to enhance yield. When batch cultures were initially conducted in a reactor, excessive foaming occurred that made the bioconversion process inoperable. This was overcome by a new aeration mechanism that provided adequate dissolved oxygen to the fermentation culture. Under the optimal conditions of 650 rpm, 28 degrees C, and 40-60% dissolved oxygen concentration, DOD production reached about 40 g (40% yield) in 4.5 L culture medium using a 7-L reactor vessel. This is the first report on a successful scale-up production of DOD.
Microbial Genomics and Bioprocessing Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, 1815 North University Street, Peoria, IL 61604, USA.
Tsung Min
TM
Kuo
Alan C
AC
Lanser
D019149:Bioreactors; D001711:Biotransformation; D003470:Culture Media; D006863:Hydrogen-Ion Concentration; D019301:Oleic Acid / Q000378:metabolism*; D009829:Oleic Acids / Q000096:biosynthesis*; D010100:Oxygen / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000254:growth & development* / Q000378:metabolism*; D012399:Rotation
C477043:7,10-dihydroxy-8-octadecenoic acid; D003470:Culture Media; D009829:Oleic Acids; D019301:Oleic Acid; D010100:Oxygen