Purification Of Phenolic Compounds In Rape Seed Pollen(brassica Capestris) And Its Antioxidant Activity

The bee pollen was one of the most nutritional food resources in the world. The bee pollen resources were rich in china, The rape bee pollen production is above 300 ton every year. The rape bee pollen has much nutrional components, including protein, polysaccharides, amino acids, phenolic compounds. People became more interested in the phenolic ccompounds.The determination methodology of phenolic compounds in rape bee pollen were established. The material used for column separation and purification were compared. The rape bee pollen had flavonoid glycosides and it could be hydrolysated into aglycones.The phenolic compounds were purified and the antioxidant activity was studied in vivo and vitro. It gave a basis for the functional activity study of bee pollen.The total content of phenolic compounds in rape bee pollen were detected by iron potassium cyanide method, Folin-phenol method and ferrous tartarte method. The standard curve were established and the precision, repetition, recovery, stability were also analysed. The results showed that the Folin-phenol method was more suitable for measuring the contents of phenolic compounds. The content of phenolic compounds in rape bee pollen was 2.274%.The phenolic compounds in rape bee pollen were purified by polyamide column and D101 macroporous resin. The contents of phenol compounds, DPPH scavenging activity and reductivity were determined. The phenolic compounds were enriched by the n-butanol and n-butanol fraction were further purified by polyamide column. The result showed that the lower polarity compounds could be purified by polyamide column. The high polarity compounds could be purified by D101 macroporous resin.The bee pollen extracts were purified by D101 macroporous resin, and the phenolic compounds content of 50% ethanol elution was 21.5%, comparing to the polyamide column purified fractions. The 50% ethanol elution had the maxium content of compounds and it also had the stronger DPPH scavenging activity.The flavone aglycones in hydrolysates were analyzed by thin layer chromatography (TLC) and HPLC. The ethanol extracts of rape bee pollen could be hydrolyzed into quercetin and kaempferol. The DPPH radicals scavenging capacity of the hydrolysates was better than the ethanol extracts of rape bee pollen. The antioxidant compounds were well analysed by TLC-DPPH method which was used to evaluat the antioxidant activity and select the functional compoents for the first time.The flavonoides were purified by D101 macroporous resin. The DPPH scavenging activity and antioxidant activity of flavonoides against lipid peroxidation mice model were investigated. The index of T-AOC, MDA and GSH in liver and the activity of T-AOC, MDA in serum were invistegated. The DPPH scavenging activity of flavonoides was lower than kaempferol. However, the flavonoides inhibit the liver MDA,increased liver GSH,increased the liver and serum T-AOC. The results showed that flavonoides had good antioxidant activity in vivo.High Performance Preparative Liquid Chromatography was used to separate the chemical constituents in D101macroporous resin 50%fraction. The kaempferol 3-O-(2"-O-β-D-glucopyranosyl)-β-D-glucopyranoside in rape bee pollen is identified by MS and NMR. The purity of kaempferol 3-O-(2"-O-β-D-glucopyranosyl)-β-D-glucopyranoside was 97.42%. The DPPH radicals scavenging capacity was 10.68% at the concentration of 750μg/ml. It had lower DPPH radicals scavenging capacity.Many functional compounds were presented in rape bee pollen and their biological activities varied. This experiment included the purification, DPPH scavenging activity, reductivity and lipid peroxidation model mice experiment of phenolic compounds. Other biological activities need to be further investigated in future.