Study On Physiological Changes And Antioxidant Activity Of Protein In Se-Enriched And Sprouted Tartary Buckwheat

In recent years,as one of the essential micronutrients for human and animal,selenium plays an important role in the body,such as preventing keshan disease,some cancers and delaying senility.Tartary buckwheat belongs to the polygonaceae plant.It is rich in nutrients,and contains flavonoid which was not found in other cereal crops.Flavonoid,such as rutin,quercetin and so on,has better effects in the prevention and treatment of diabetes,cardiovascular disease and hypertension,so it is recommended as the main raw material of food for those people.With increasing of the research on selenium-rich foods,there had been selenium-rich brown rice,selenium-rich wheat,selenium-rich soybean,selenium-rich garlic,selenium-rich tea,selenium-rich cucumber and so on,but few studies on selenium-rich tartary buckwheat were done.This study chose tartary buckwheat as raw material,and made tartary buckwheat seeds enriching selenium by germinating.The content of total selenium,organic selenium,and selenium in biological macromolecules and selenium in component protein?albumin,globulin,gluten and alcohol-soluble protein?were studied in sprouted tartary buckwheat to determine the optimal Se-enriched concentration.At different concentrations of Na₂SeO₃ solution,GSH,MDA,reducing sugar and other physical and chemical indexes,the activity of SOD,POD and CAT were studied.Furthermore,the antioxidant properties of component proteins in Se-enriched and sprouted tartary buckwheat were studied and purified by Sephadex G-100 GFC and DEAE-Sephcrose-FF IEC.The results were as follows:1.It was found that when the concentration of Na₂SeO₃ solution was 20?g/L,the content of total selenium,organic selenium,selenium in biological macromolecules and selenium in four kinds protein reached the maximum in Se-enriched and sprouted tartary buckwheat,the total selenium and selenium of component protein were 26.74%–52.00%higher than unsprouted and Se-unenriched tartary buckwheat.The organic selenium accounted for about93.00%in the total selenium,and the treatment of Se-riching and sprouting had the greatest influence on the content of selenium in gluten.Moreover,there was no significant difference in content of globulin and gluten,and the content of albumin was the lowest among four kinds component protein.The content of selenium combined with protein,polysaccharide and nucleic acid increased by 0.93 times,1.62 times and 2.25 times than unsprouted and Se-unenriched tartary buckwheat respectively.The content of selenium combined with protein was higher than polysaccharide and nucleic acid in sprouted tartary buckwheat.2.The content of reducing sugar,soluble sugar,free amino acid and V_C was increased 1.61times,1.13 times,1.46 times and 2.19 times by enriching selenium and sprouting process in tartary buckwheat,compared with unenriching selenium and non-sprouting.With the increase of concentrations Na₂SeO₃ solution,the change trend of index was different.The activity of SOD first decreased and then increased,and the content of V_C first increased and then decreased.Therefore,the best effect was obtained by using 20?g/L Na₂SeO₃ solution to Se-enriching and sprouting tartary buckwheat.3.Four kinds component protein has certain antioxidant activity.The DPPH radical scavenging ability of globulin was the highest,the reducing power of alcohol-soluble protein was the highest,and the ABTS radical scavenging capacity of gluten was the largest,which may be related to the structure of protein and the content of Se-enriched.4.Six protein peaks were obtained by Sephadex G-100 GFC,mainly distributed in peak 3,the content of which accounted for 68.36%of total protein.The protein of Peak 3 was separated and purified by DEAE-Sephcrose-FF IEC,and seven protein peaks were obtained,and the proteins was mainly distributed in peak 1 with lesser electricity,the content accounted for 38.07%of total protein,which providing theoretical basis for the study of selenium-rich proteins.