Study On Extraction And Bioactivity Of Polyphenol From Boletus

In the present work, the optimum extraction conditions of polyphenols from Boletus auripes Peck, Leccinum crocip odiumWalt., Boletus edulis Bull and Boletus aereus were studied. Then, the types and contents of polyphenols of these four wild edible fungi were analyzed by high performance liquid chromatography (HPLC).And the antioxidant, antitumor activities and coating preservation activities of the extracts from these four wild edible fungi were also evaluated. The main results obtained are as follows:(1) The optimum extraction conditions for polyphenols of Boletus auripes Peck were:70 ℃,60%ethanol,1:15 (w:v) of the ratio of material and solvent, extraction for 1.5 h with two times. Under this condition, polyphenol extraction rate was 3.04 ± 0.04%. The optimum extraction conditions for Leccinum crocip odiumWalt. were:80 ℃,60% ethanol,1:25 (w:v) of the ratio of material and solvent, extraction for 1.0 h with two times. Under this condition, polyphenol extraction rate was 5.46±0.04%. For Boletus edulis Bull, the optimum conditions were:80 ℃,50% ethanol,1:30 (w:v) of the ratio of material and solvent, extraction for 1.5 h with two times. Under this condition, polyphenol extraction rate was 2.01±0.01%. The optimum conditions for extraction of polyphenols of Boletus aereus were:80 ℃, 60% ethanol,1:20 (w:v) of the ratio of material and solvent, extraction for 1.0 h with two times. Under this condition, polyphenol extraction rate was 3.32±0.03%.(2) There are differences in the types and contents of polyphenols contained in four wild edible fungi. Among the 18 kinds of polyphenols, only 5-sulfosalicylic acid, catechin and cinnamon were all detected in those four edible fungi and 5-sulfosalicylic acid had the highest content with 1100.88,779.00,1369.25,1546.5 mg /100g, respectively.(3) The 60% ethanol extracts of four wild edible fungi showed good DPPH, ABTS and hydroxyl free radical scavenging abilities with a dose-dependent manner. Ferric reducing ability of wild edible fungi was between 0.02 and 0.04. In all, Leccinum crocip odium showed the best antioxidant activity,while Boletus aereus had the worst antioxidiant activity.(4) The extracts of all these four wild edible fungi had inhibition effect on the proliferation of the Caco-2 colon cancer cells. Leccinum crocip odiumWalt. showed the best inhbition effect, while Boletus aereus was the worst. When the polyphenol concentration reached 175 ug/mL, the inhibition rate were 29.57%,55.07%,22.46% and 8.34%for Boletus auripes Peck, Leccinum crocip odiumWalt, Boletus edulis Bull and Boletus aereus, respectively.(5) The ethanol extract of Leccinum crocip odium Walt, could effectively delayed the increase of total number of bacteria pH, TVB-N and TBARS in pork, reduced juice loss and improved the flavor, luster and organizations morphological of pork during storage to ensure food quality and extend the shelf life. Moreover, there was a positive correlation between preservation effect and polyphenol content of the ethanol extract from Leccinum crocip odium Walt. Compared to the control group, the ethanol extract from Leccinum crocip odium Walt had a good preservation effectat 40mg/mL polyphenols content.