Table 1: Scientific name, common name and sources of mushroom samples. Absolute acetone and absolute ethanol were offered by Guangzhou Chemical Reagent Factory (Guangzhou, China). 2-Diohenyl-1- picryhydrazyl (DPPH) was supplied by Shanghai Yuanye BiologicalTechnology Co., Ltd (Shanghai, China). Folin-Ciocalteu reagent was provided by Shanghai Sanjie Biotechnology Co., Ltd (Shanghai, China). Trolox was purchased from Aldrich Co. (St. Louis, MO, U.S.A.). Sodium carbonate was supplied by Tianjin Nuoke Technology Development Co., Ltd (Tianjin, China). Gallic acid was purchased from Tianjin Damao Chemical Reagent Co., Ltd (Tianjin, China). All the chemicals were of analytical grade. Each of the twenty dry mushroom samples was pulverized; 5.0 g of each mushroom powder was accurately weighed into a set of centrifuge tubes (each of the sample prepared in triplicate); 40 mL of absolute acetone was added into each tube for the preparation of acetone extracts. The samples were extracted for 24 hours and then centrifuged by a centrifuge (Weierkang Xiangying Centrifuge Co., Ltd, Changsha, Hunan, China) at 8000 rpm for 10 min.
The supernatants were transferred into new centrifuge tubes and stored at −20 degree C. The residues were dried by vaporizing and collected; 40 mL of absolute ethanol was added into the dry residues for the preparation of ethanol extracts. The same extraction procedures were repeated to prepare water extracts as acetone and ethanol extraction and finally hot water extraction was done at 99°C in water bath for 2 hours. All the extracts were stored at −20°C in the dark for further usage. For determination of organic extracts, 1 mL of each acetone extract, ethanol extract, blank and standard solutions was added into a pre-labeled test tube and mixed with 3 mL of DPPH solution. Fordetermination of aqueous extracts, 0.2 mL of each water extract, hot water extract, blank and standard solutions was added into a prelabeled centrifuge tube and mixed with 3.8 mL of DPPH solution. The mixtures were mixed evenly by vortexing and stood in the dark at room temperature for 20 min.
Then the mixtures were centrifuged by a centrifuge (Weierkang Xiangying Centrifuge Co., Ltd, Changsha, Hunan, China) at 3000 rpm for 10 min. The absorbance of each mixture was measured by an UV-Visible spectrophotometer (TI- 1901, Beijing Purkinje General Instrument Co., Ltd, Beijing, China) at 517 nm against solvent blank. The results were expressed as Trolox equivalents (µmole of TE⁄g sample) in accordance to the standard curve of Trolox. For determination of water extracts, 50 µL of each water extract, hot water extract, blank and standard solution was mixed with 3 mL of distilled water, 250 µL of Folin-Ciocalteu reagent and 750 µL of 7% Na2CO3 solution and the mixtures were mixed evenly by vortexing. If you cherished this report and you would like to acquire more details concerning manufacturer of shiitake mushroom extract powder for pharmaceutical Ingredients kindly visit our own web page. After standing at room temperature for 8 min, 950 µL of distilled water was added into each mixture and the mixtures were allowed to stand at room temperature for 1 hour. For organic solvent extraction, 500 µL of each acetone extract, ethanol extract, blank and standard solution was mixed with 2.55 mL of distilled water, 250 µL of Folin-Ciocalteu reagent and 750 µL of 7% Na2CO3 solution.
The absorbance of each mixture was measured by the UV-Visible spectrophotometer (TI- 1901, Beijing Purkinje General Instrument Co., Ltd, Beijing, China) at 765 nm by using distilled water as the blank. The total phenolic content (TPC) was expressed as gallic acid equivalents (mg of GAE⁄g sample) in accordance to the standard curve of gallic acid. The data obtained were analyzed by ANOVA with the use of SPSS Statistics (Version 17.0, SPSS Inc., Chicago, IL, U.S.A.). Duncan’s multiple range test was used to test whether there was any significant difference in antioxidant activity or total phenolic content among different mushroom species. The DPPH free radical scavenging activity of extracts from 20 different mushrooms was tested. Antioxidant capacities of the 80 extracts from 20 different mushrooms with four different extraction solvents were presented in Table 2. Three mushroom species (Boletus edulis, B. luridus and B. aereus) provided a relative higher antioxidant activity for all four extraction solvents as compared to the other 17 species.