May 6/Journal of Farming -- "Crude glycerol is a major byproduct for the biodiesel industry. Producing value-added products through microbial fermentation on crude glycerol provides opportunities to utilize a large quantity of this byproduct," U.S. investigators report.
"The objective of this study is to explore the potential of using crude glycerol for producing eicosapentaenoic acid (EPA, 20:5 n-3) by the fungus Pythium irregulare. When R irregulare was grown in medium containing 30g/L crude glycerol and 10g/L yeast extract, EPA yield and productivity reached 90mg/L and 14.9mg/L.day, respectively. Adding pure vegetable oils (flaxseed oil and soybean oil) to the culture greatly enhanced the biomass and the EPA production. This enhancement was due to the oil absorption by the fungal cells and elongation of shorter chain fatty acids (e.g., linoleic acid and a-linolenic acid) into longer-chain fatty acid (e.g., EPA).