Study On The Extraction Of Elaeagnus Mollis Diels Seed Oil And Its Antioxidant Activity

Elaeagnus mollis Diels as a rare and endangered plant in China,is a kind of rare oil plant with high economic value.Elaeagnus mollis Diels seed oil is a kind of functional oil with abundant nutrients and high quality.However,there are some problems in the development of Elaeagnus mollis Diels seed oil such as the lack of systematic research on the Elaeagnus mollis Diels seeds,the single optimization of the extraction process,and the unclear basis of the antioxidant capacity.Therefore,this paper aimed to solve the above-metioned problems for further commercial application of Elaeagnus mollis Diels.In this paper,appropriate Elaeagnus mollis Diels seeds were selected and an orthogonal method was used to optimize the supercritical CO₂ fluid extraction?SFE?parameters of Elaeagnus mollis Diels seed oil according to the results of single factor experiments.The antioxidant capacities of Elaeagnus mollis Diels seed oil and different parts extracted by different methods were analyzed.The research contents and results were as follows:Firstly,the moisture content,fat content,amino acid content and mineral content in Elaeagnus mollis Diels seeds at different degrees of maturity,altitude,and different origins were determined to screen high-quality seeds.Then the unsaponifiable matter content,total sterol,vitamin E and squalene contents in Elaeagnus mollis Diels seed oil were also determined.Based on the analysis and comparison of Elaeagnus mollis Diels seeds collected in different degrees of maturity,altitude and different origins,it is clear that the Elaeagnus mollis Diels seeds at a maturity period of 60 days and an altitude of 1200 m collected in xijiaokou were the most suitable one for the extraction of Elaeagnus mollis Diels seed oil.Secondly,the effects of extraction pressures,extraction temperatures,extraction time,moisture content and particle size of raw material on the oil yield,vitamin E?V_E?,squalene and sterol content in Elaeagnus mollis Diels seed oil during the supercritical CO₂ fluid extraction process were studied.According to the results of single factor experiments the extraction pressure,extraction temperature,extraction time,particle size of raw material were used to optimize the SFE process.The results of the orthogonal experiment were analyzed by the oil yield,vitamin E,squalene and sterol content intuitively.The optimum extraction parameters of SFE were determined as follows:extraction pressure 30 MPa,extraction temperature 50°C,extraction time 150 min and particle size 80 mesh.Compared with organic solvent extraction,cold pressing,hot pressing,and IHP,the oil yield,V_E,squalene and total sterol content in Elaeagnus mollis Diels seed oil extracted by SFE were lower than the highest extraction method,but higher than the other extraction methods significantly.This indicated that SFE is a suitable extraction process of Elaeagnus mollis Diels seed oil.Finally,the antioxidant capacity of oil,polar fractions and non-polar fractions in the Elaeagnus mollis Diels seed oil extracted by different methods were evaluated with DPPH,ABTS,hydroxyl radical scavenging and PF reducing power as indexes.Results of DPPH radical scavenging ability tests indicated that the antioxidant capacities of Elaeagnus mollis Diels seed oil extracted by different extraction methods had no significant differences?p>0.05?.The results of hydroxyl free radical scavenging ability analysis suggested that there were no significant differences in the antioxidant capacities of oil,polar part and non-polar part extracted by five different methods.ABTS free radical scavenging ability analysis indicated that the antioxidant capacity of Elaeagnus mollis Diels seed oil,polar part and non-polar part extracted by organic solvent method were the highest.However,the antioxidant capacities of Elaeagnus mollis Diels seed oil and polar part using SFE as well as the antioxidant capacity of the non-polar part extracted by hot pressing were the lowest.PF reducing power tests proved that the antioxidant capacity of Elaeagnus mollis Diels seed oil extracted by organic solvent method was significantly higher than the other four extraction methods.The antioxidant capacity of the polar part extracted by infrared hot pressing was the highest.The antioxidant capacity of the non-polar part extracted by organic solvent method was remarkably higher than that obtained by other extraction methods.The correlation analysis showed that the bioactive substances in Elaeagnus mollis Diels seed oil were highly correlated with their antioxidant activities?p?27?0.01?.The essential antioxidant substances in Elaeagnus mollis Diels seed oil were?-tocopherol,?-tocopherol,and lupeol.