Enrichment Of Unsaterated Fatty Acid And Oxidation Stability Of Phyllanthus Emblica L. Seed Oil

In traditional process,Phyllanthus emblica L.fruit was mainly used as raw material,and Phyllanthus emblica L.seed was usually abandoned.It not only resulted a waste of resources but also incressed environmental pressure.According to incomplete statistics,the production of Phyllanthus emblica L.fruit was 100,000 tons in Yunnan province,of which the proportion of Phyllanthus emblica L.seed was 1.8%.Given all that,Phyllanthus emblica L.seed was used as raw material to extract Phyllanthus emblica L.seed oil.On this basis,polyunsaturated fatty acids?FUFAs?were separated and then ?-linolenic acid was seperated and purified.In addition,antioxidant activity and oxidative stability of Phyllanthus emblica L.seed oil were studied.The main contents are as follows:?1?Acumulation of polyunsaturated fatty acid from Phyllanthus emblica L.seed oil by urea inclusion fractionation: The effects of urea and methanol amounts,crystallization temperature and crystallization time on the content and yield of PUFAs were investigated.Optimum technology was employed and the results were obtained as follows: ure?-to-free fatty acids?W/V?of 2,methanol-to-free fatty acids?V/V?of 18,crystallization temperature of-6 ?,and crystallization time of 19 h.Under these conditions,the PUFAs content and yield were 98.47% and 71.85% respectively.The urea inclusion whose thermodynamic properties,structure,morphology,visual spectrum and energy spectrum was characterized by differential scanning calorimetry?DSC?,IR spectroscopy?FT-IR?,X-ray diffraction?XRD?and field emission scanning electron microscopy?SEM-EDS?respectively.PUFAs which came from Phyllanthus emblic L.seed oil were successfully separated and accumulated by urea inclusion fractionation.?2?Separation and purification of ?-linolenic acid from PUFAs by silver iron complexation: The effects of silver nitrate concentration,volume fraction of methanol,complexation time and complexation temperature on the purity and yield of ?-linolenic acid?ALA?were investigated in silver iron complexation process.Optimum technology was employed and the results were obtained as follows: complexation temperature of 0 ?,silver nitrate concentration of 2.29 mol/L,methanol volume fraction of 38.00%,complexation time of 1.93 h,the purity and yield of ?-linolenic acid were 93.30% and 73.37%,respectively.The recovery of silver nitrate was 93.83% and the recovery of Ag⁺ still had good complexation effect.It's worth mentioning that Ag⁺ was not introduced in the final products.Therefore,this method not only successfully separated and purified ?-linolenic acid which came from Phyllanthus emblica L.seed oil,but also reduced the operating cost.In a meanwhile,the method of silver iron complexation had a certain safety,which laid a good foundation for industrial application of Phyllanthus emblica L.seed oil.?3?Antioxidant activity and functional mechanism in vitro of Phyllanthus emblica L.seed oil: 2,2'-azinobis-?3-ethylbenzthiazoline-6-sulphoate??ABTS?radical and1 1-dphenyl-2-picrylhydrazl?DPPH?radical were employed to evaluated the antioxidant activity by free radical scavenging.The results indicated that the scavenging capacity of Phyllanthus emblica L.seed oil to DPPH radical and ABTS radical were 95.91% and 98.58%,the IC₅₀ to DPPH radical and ABTS radical were 5.08 mg/m L and 9.84 mg/mL respectively.Free radicals scavenging experiment of ALA showed that the main antioxidants in Phyllanthus emblica L.oil were PUFAs.Conjugated fatty acid and hydroxy fatty acid were detected in free fatty acids?FFA?after oxidation characterized by ultraviolet scanning spectrum?UV?and fourier transform infrared spectroscopy?FT-IR?.Moreover,monohydroxy fatty acid was detected through gas chromatography mass spectrometry?GC-MS?under the condition of excessive DPPH radical,all the above indicated that the free radicals scavenging of polyunsaturated fatty acids included polyunsaturated fatty acid conjugation,single molecule addition,?-H oxidation of C=C double bond and epoxidation reaction at least.?4?Evaluation of oxidation stability and shelf life prediction of Phyllanthus emblica L.seed oil: Synthetic antioxidants,natural antioxidants and the complexion of synergists and antioxidants were employed to evaluate the effects of oxidation induction time in Phyllanthus emblica L.seed oil.The results indicated that complexion of citric acid with ascorbyl palmitate?AP?and tertiary butylhydroquinone?TBHQ?revealed most obvious antioxidant.The effects of environmental factors on oxidation induction time before and after added antioxidants were investigated which were Fe³⁺,Fe²⁺,Zn²⁺,Cu²⁺,ultraviolet light time and temperature.The results showed that Fe³⁺,Fe²⁺,Cu²⁺,the time of ultraviolet light and temperature can significantly affect the oxidation induction time of Phyllanthus emblica L.seed oil.The micro-encapsulation of Phyllanthus emblica L.seed oil was made by spray-drying.The effects of emulsifier concentration,gum acacia to maltodextrin ratio,core to wall ratio and soild concentration on the efficiency of Phyllanthus emblica L.seed oil micro-encapsulation was investigated in spray-drying process.Optimum technology was employed and the results were obtained as follows: emulsifier concentration was 1.5%?wt%?,the ratio of gum acacia to maltodextrin was 7:24?m:m?,the ratio of core to wall was 2:3?m:m?,solid concentration was 14.2%?wt%?,the efficiency of Phyllanthus emblica L.seed oil micro-encapsulation was 90.74%.Under the condition of 25 ?,the complexion of citric acid with TBHQ could prolong the shelf life of Phyllanthus emblica L.seed oil from 128 days to 419 days,and the shelf life of Phyllanthus emblica L.seed oil micro-encapsulation was 716 days,which two methods could significantly improved the storage ability.