Study Of Highly Productive PUFAs Optimization Culture By Fermentation

Fatty acid is important nutrient source.Whereas polyunsaturated fatty acids play a more important role in humanity normal vital movement.They are not only necessary for maintaining vital movement but prevent and cure a great many sickness for human.Producing PUFAs by fermentation is free from raw material,climate,producing area' restrict,and has some merits,for exameple,being easy to produce in a big way and industrialization produce and so on.Some aspects were studied in this subject included:(1) isolating test strain from conservative Mortierella isabellina,(2) optimizing culture medium for highly productive PUFAs by fermentation,(3) optimizing fermentation conditions for highly productive PUFAs,(4) checking and measuring physical and chemical characters from Mortierella isabellina strain oil.By primary screening of Mortierella isabellina producing fat culture medium, No 3 culture medium and No 8 culture medium were finally choosed as optimized culture medium.Analyzing the strain oil of No 8 culture medium and No 3 culture medium by gas chromatography,it showed that saturated fatty acids in fatty acids of the Mortierella isabellina oil was 14.50% and unsaturated fatty acids in fatty acids of the Mortierella isabellina oil was 85.21% and unsaturated fatty acids in the total fatty acids was 85.46% in the No 8 culture medium,and saturated fatty acids in fatty acids of the Mortierella isabellina oil was 14.02% and unsaturated fatty acids in fatty acids of the Mortierella isabellina oil was 85.45% and unsaturated fatty acids in the total fatty acids was 85.91% in the No 3 culture medium.No 8 culture medium yielded 8.07% C18:3n3 and 6.80% in the oil contend was C18:3n6; No 3 culture medium yielded 8.97% C18:3n3 and 6.50% in the oil contend was C18:3n6.It showed that No 8 culture medium was better than No 3 culture medium by the primary optimized culture medium and fermentation conditions,and No 8 culture medium was ultimately selected to be more step optimized conditions try.After No 8 culture medium was fermented in No 1 opotimized condition and No 2 opotimized condition,No 1 opotimized condition was selected as opotimized condition because of the oil yield in No 2 opotimized condition lower it in No 1 opotimized condition.Checking and measuring the fatty acid composition of No 8 culture medium in No 1 opotimized condition by gas chromatography,it showed that average fatty acid composition was C16:0 9.65%,C18:0 2.05%,C18:1n9 50.00%, C18:2n6 23.35%,C18:3n3 1.35%,C18:3n6 8.65%,C20:0 0.40%,C20:1 0.69%,C20:2n6 0.35%,C24:1(n-6) 0.60%,average contend of unsaturated fatty acids in the total fatty acids was 87.03%.Through checking and measuring Mortierella isabellina gross oil , we discovered that other physical and chemical characters were in accord with recommended the microbial oil standard other than higher acid value.This showed that the refined strain oil was edible.