| Tenebrio molitor is rich in nutrition value which is very important for human body. It is one kind of resource insects which has a huge potential of being explored. To improve the available use of resource insects and research the oil of them, using Tenebrio molitor as material, We did some research in extraction, purification and functional test of Tenebrio molitor oil and its polyunsaturated fatty acid in this study.Using petroleum ether as solvent to extract oil from Tenebrio molitor. Aiming at optimization of the extraction of Tenebrio molitor oil, test factors and levels were firstly selected by one-factor tests.On the basis of previous results and according to the Box Benhnken test design principles, the model of response surface methodology (RSM) with 3 factors and 3 levels was adopted. Response surface and contour were finally graphed with the extraction rate of Tenebrio molitor oil as the response value.The results showed that the optimum conditions of Tenebrio molitor oil extraction were:extraction temperature:57.9℃, extraction time:10.1h, extraction ratio of material to liquid:2:50.The real extraction rate of Tenebrio molitor oil under these conditions was up to 31.51%,and it was 2.34% higher than the best result of one-factor tests.Technology of oil extraction was improved by response surface methodology, the extraction rate was higher, it means that the method was effective and economical.The optimal process on purification with urea was ascertained by the single factor experiments and the response surface methodology design. The optimal purification conditions were that the ratio of urea to fatty acid was 1.6:1,the saponification time was 34min and the inclusion time was 13.5h. In these conditions, the conclusions were that the I2 value of polyunsaturated fatty acid was 217.52.Through the analysis of GC before and after urea inclusion, the content of unsaturated fatty acid was raised from 63.44% to 90.35%,the content of monounsaturated fatty acid and saturated fatty acid was respectively decreased from 24.21% and 11.70% to 7.58% and 1.87%, the content of linoleic acid (LA,18:2) after urea inclusion was up to 55.22%, the content of a-linolenic acid (ALA,18:3) was up to 35.13%.After polyunsaturated fatty acid was concentrated from Tenebrio molitor oil by urea inclusion method.50 rats were devided into 5 groups randomly. Except blank control group, the other 4 groups were fed with high fat diet. Blank control and obesity control groups were fed with 1.2g/kg·bw physiological salt water, and the doses groups were fed with 0.4g/kg·bw, 1.2g/kg·bw and 2.0g/kg·bw unsaturated fatty acid. Body weights were weighed every week. After 4 weeks, the rats were killed, the blood and hepar were collected. The serum total triglycerides (TC), total cholesterol (TG), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C), hepar hepaticlipase (HL), lipoprotein (LPL), malondialdehyde (MDA) and hepar ipofuscin (LP) were assayed. High dose group compared with obesity control group, the body weight (P<0.01),TC (P<0.01),TG (P<0.01),LDL-C (P<0.01) and MDA (P<0.01)levels were reduced remarkably; HDL-C (P<0.01),HL (P< 0.01),LPL (P<0.05) and LA (P<0.01)levels were enhanced remarkably; there was no remarkably change of LP level. It indicated that Tenebrio molitor unsaturated fatty acid could enhance the rat's lipid metabolism.
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