Preparation of High Ergothioneine of Pleurotus eryngii -Fermented Grains Using Solid State Fermentation and Their Taste Quality and Physiological Activities

• Main Authors: Kung-Jui Ho, 何公瑞
• Other Authors: 毛正倫
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/39446521309525979290

碩士 === 國立中興大學 === 食品暨應用生物科技學系所 === 97 === Ergothioneine is a kind of precious amino acid, and it is also a natural antioxidant. It plays an important role to prevent the oxidative damage in organism. Ergothioneine cannot be biosynthesized in humans, only can be absorbed from the diet. In recently the research discovered the high content of ergothioneine in the mushroom. Content of ergothioneine of Pleurotus eryngii is the highest from 28 kinds of mushrooms, therefore the research untilized P. eryngii to make the products of P. eryngii-fermented adlay(PFA) and P. eryngii-fermented buckwheat(PFB) which content high ergothioneine. Also, we analyzed their proximate composition, nutritional components, taste and physiologically active components, antioxidant properties and evaluation of anti-imflammatory effect. Ergothioneine of PFA and PFB at various culture condition, investigated optimal incubation to intent to get hight content of ergothioneine. Results showed that optimal conditions for high content of ergothioneine were moisture content at 40%, temperature at 30℃and polished adlay (PA) as medium, cubation 17 days (574.0 mg/kg dw), biomass was 139.0 mg/g dw. The addition of yeast extract for nitrogen source can increase content of ergothioneine (824.8 mg/ml dw)；Fermentation of Pleurotus eryngii was polished buckwheat (PB) as medium, moisture content at 45%, temperature at 30℃and cubation 17 days could get high content of ergothioneine (580.6 mg/kg dw), and biomass was 163.4 mg/g dw, yeast extract as nitrogen source (651.6 mg/kg dw), Fructose as carbon source (721.4 mg/kg dw). With regard to proximate composition, carbohydrate (87.64%, 85.55%, 78.43%, 78.77%, 50.14%) were major components found in PA, PFA, PB, PFB and mycelia. With regard to physiologically active components, the contents of ergosterol and ergothioneine of mycelia (2056.4 mg/kg dw and 1514.6 mg/kg dw) were higher than others. With regard to bioactive components, rutin and quercetin of polished buckwheat was 198.56 mg/kg and 10.77 mg/kg. With regard to taste characteristics, total soluble sugar contents of P. eryngii mycelia was the highest at 411.70 mg/g dw. PA and PB by mycelia after its solid- state fermenrtation, free amino acid contents increase from 14.38 mg/g dw to 46.24 mg/g dw and 24.06 mg/g dw to 45.28 mg/g dw. Total nucleotide contents of mycelia was highest at 1.70 mg/g dw. The antioxidant of hot water extracts were highest at 92.55% and 92.79% at 20mg/ml for PB and PFB. The reducing powders of PB showed an great(1.31) at 20 mg/ml. The scavenging abilities on 1,1-diphenyl-2- picrylhydrazyl radicals were in the descending order PFB (84.59%)＞PB (63.10%)＞PFA (50.31%)＞mycelia (48.56%)＞PA (47.31%). With regard to chelating abilities on ferrous ions, the chelating abilities of PFB can reach 90.52％ at 20 mg/ml. With regard to ethanolic extracts, the antioxidant activities of PA, PFA, PB, PFB and mycelia at 20mg/ml were 100%, 39.14%, 92.03%, 59.51% and 33.93%. The reducing power of mycelia (0.55) was the highest at 10 mg/ml. At 20mg/ml, the scavenging abilities on 1,1-diphenyl-2- picrylhydrazyl radicals were in the descending order: PFA (97.81%), mycelia (96.89%), PA (92.67%), PB (92.92%), PFB (91.25%). With regard to chelating abilities on ferrous ions, the chelating ability of PA was the highest (100%) at 20 mg/ml, PB was the second (87.05%). In the anti-inflammation effect test, the inhibition on the growth of RAW 264.7 cells was studied in a MTT test using hot water extracts from PA, PFA, PB, PFB and mycelia. Increased of five samples concentrations did not inhibit the growth of RAW 264.7 cells. Effect of hot water extracts from PA, PFA, PB, PFB and mycelia on LPS-induced NO production in RAW 264.7 cell in the descending: PFA(39.58 μM)＞PFB(29.77 μM)＞PB(29.16 μM)＞PA(29.89 μM)＞mycelia(28.48 μM). And it is no effect to inhibit LPS-induced TNF-α production in RAW 264.7 cell. With regard to ethanolic extracts, the effect of PFA(73.71%), PFB(80.12%) and mycelia(81.28%) on the growth of RAW 264.7 cell showed inhibition at 1000 μg/ml. Effect of hot water extracts from PA(33.56 μM), PFA(35.43 μM) and mycelia(21.96 μM) on LPS-induced NO production in RAW 264.7 cell showed inhibition at 500 μg/ml. The effect of PA(4.64 ng/ml), PFA(4.49 ng/ml), PB(4.82 ng/ml), PFB(3.91 ng/ml) and mycelia(0.41 ng/ml) on the LPS-induced TNF-α production in RAW 264.7 cell showed inhibition at 500 μg/ml. In conclution, PFA and PFB prepared from the solid state fermentation of polished adlay and buckwheat have better nutritional, taste quality and physiologically active components, antioxidant properties and anti-inflammation activity.