Producing EPA And DHA From Biodiesel-Derived Crude Glycerol

In recent years, with the energy shortage, international oil prices continue to rise, as well asenvironmental degradation, bio-diesel act as an extremely development promising in bio-energy,large-scale development of bio-diesel has got a lot of attention. At the same time, the biodieselbyproduct glycerol production is increasing rapidly, which is much larger than the traditionalglycerol market demand. Therefore, the effective use of low-cost crude glycerin in the biodieselproduction process is becoming a serious and critical problem. Vigorously the development anduse of glycerol can reduce the cost of preparation of biodiesel, to reduce environmental pollution,and enhance market competitiveness. Many microorganisms can utilize glycerol production ofvaluable products, the microbial transformation of biodiesel byproduct glycerol is one of theefficient ways to tackle pollution and improve the biodiesel industry economic benefits.In this study, the biodiesel byproduct glycerol was used as the carbon source, using culturedPythium irregulare fermentation production of EPA and the use of culture S. limacinumfermentation production of DHA, respectively, and the fermentation process was optimized toidentify more appropriate fermentation conditions.The use of biodiesel byproduct glycerol as carbon source, the culture of Pythium irregularefermentation production of the EPA, culture S. limacinum fermentation production of DHA.Waste glycerol used in the experiment is provided by ester exchange reaction of alkali-catalyzedsoybean oil and methanol, crude glycerol is purified refined as a carbon source. EPA and DHAproduction by gas chromatography analysis, before the analysis, using concentrated sulfuric acid-methanol esterification of fatty acid methyl esters. The results shows that the EPA optimumfermentation conditions were: temperature is25℃, pH6, speed170r/min, the amount of crudeglycerol70g/L, the EPA yield obtained under this condition:105mg/L,the optimum fermentationconditions Of DHA are: temperature25℃, pH7, the speed170r/min, the amount of crudeglycerol75g/L, the DHA yield obtained under this condition:3.5g/L.In summary, the use of biodiesel byproduct crude glycerol as the carbon source,fermentation production of EPA and DHA is feasible. Biodiesel byproduct crude glycerininexpensive, easy to buy, has a good application potential, is expected to replace conventionalcarbon sources, and industrial production.