Studies On The Extraction And Purification And The Antioxidant Performance Of Lipid From Abalone Viscera

China is the largest country in abalone culture and consumption worldwide coverage.Abalone viscera were the major byproduct in the processing.However,there have been few studies on it.This paper systematically studied the fatty acids of visceral lipid in Haliotis discushannai Ino and its antioxidant activity,which provided the theoretical and technical basis for the development of abalone visceral phospholipids and new marine functional foods.The main results included:(1)Using the five different extraction solvents of chloroform/methanol,n-hexane,cyclohexane/ethyl acetate,the crude fat and phospholipids were extracted from the abalone viscera.Analyzed the influence of different solvents on extraction efficiency of the fat and phospholipids,and on the fatty acids composition by gas chromatography-mass spectrometry(GC-MS).The results showed that the yield of crude fat and phospholipids was 14.87±0.49%and 11.48±0.71%,respectively,with n-hexane/ethyl acetate(3:1,V/V)as the extractant.There were some differences in the extraction yield,fatty acids composition and content of crude fat and phospholipids using the five different solvents.The most unsaturated fatty acids extracted from cyclohexane/ethyl acetate have 12,accounting for 30.82%,Of which the ω-3 series acids(linolenic acid,eicosapentaenoic acid,docosahexaenoic acid)accounted for 7.71%.Considering the properties of extractants,the yield of fat and the nutrient utilization value of fatty acids,cyclohexane/ethyl acetate was used as the optimum solvent for the extraction of abalone visceral oil.(2)Determine the phospholipids composition in abalone viscera by high performance liquid chromatography-evaporative light scattering(HPLC-ELSD)using abalone visceral crude fat as raw material.The results showed that the components of abalone visceral phospholipids were complex,but the main phospholipids compositions were phosphatidyl choline(PC),phosphatidyl inositol(PI),phosphatidyl ethanolamine(PE)and sphingomyelin(SM).(3)The abalone lecithin was obtained by purifying the acetone insoluble with ethanol using abalone visceral crude fat as raw material.And the relationship of lecithin yield and ethanol concentration,extraction time and the ratio of material to ethanol were established by the orthogonal orthogonal rotation experiment.The regression equation is Y=29.01+1.91*A+1.21*B-0.81*C-0.48*A*B-1.27*A*C-0.19*B*C-5.59*A2-4.34*B2-4.14*C2.The regression model and the actual situation were fitting,which can be used to reflect the influence on the yield of abalone lecithin of ethanol concentration,extraction time,and the ratio of acetone insoluble to ethanol in actual production.(4)The best process parameters of ethanol purifying acetone insoluble material to obtain abalone visceral lecithin included:the crude phospholipids preparation process:the ratio of abalone visceral crude fat and 4℃ cold acetone was 1:9,the extraction time was three times,the acetone extraction time was 40min;the lecithin purification process:the ethanol concentration of was 92%,the extraction time was 41 min,and the ethanol ratio of acetone insoluble to liquid was 1:10.The abalone visceral lecithin yield was up to 29.11%on this condition.(5)We studied the abalone visceral phospholipids and its antioxidant activity using abalone viscera as the raw material.The results showed that the reducing ability,hydroxyl free radical scavenging ability and DPPH·scavenging ability of abalone visceral crude phospholipids were significantly higher than those of Vc in the experimental concentration range.But the ability to remove superoxide anion free radicals was close to that of Vc.In the experiment,the antioxidant effect of abalone visceral crude phospholipids in soybean oil and rapeseed oil was similar to that of 0.02%TBHQ when the added amount reached a certain concentration.In this experiment,the antioxidant effect showed relatively more obviously in soybean oil.(6)Determined the rule of oxidation susceptibility of abalone viscera compositions with the change of the the storage time and temperature by gas chromatography-mass spectrometry(GC-MS)with headspace solid-phase microextraction(SPME).The results showed that the components including aldehydes,alcohols,ketones,acids,esters,hydrocarbons,furan and ether changed significantly with the storage time and temperature.