菌株MP-24產(chǎn)單寧酶的條件優(yōu)化和生物轉(zhuǎn)化茶多酚
發(fā)布時間：2018-10-09 20:27
【摘要】：單寧酶,即單寧�；饷�(E.C.3.1.1.20),可以水解單寧酸中的酯鍵,將單寧酸完全水解為沒食子酸和葡萄糖。單寧酶被廣泛應(yīng)用于食品、飼料、制藥,飲料、釀造和化工等行業(yè)。本研究對產(chǎn)單寧酶菌株MP-24進行初步鑒定,優(yōu)化其固體發(fā)酵培養(yǎng)基配方和發(fā)酵條件,并應(yīng)用于茶多酚和茶湯的生物轉(zhuǎn)化,采用HPLC和LC-MS分析法分析單寧酶轉(zhuǎn)化產(chǎn)物,檢測轉(zhuǎn)化產(chǎn)物的抗氧化活性。對菌株MP-24進行結(jié)合形態(tài)學(xué)觀察和ITS序列分析之后,初步鑒定其為青霉屬(Penicillium)真菌。對該菌株固體發(fā)酵產(chǎn)單寧酶的固體發(fā)酵培養(yǎng)基配方和培養(yǎng)方法進行單因素-響應(yīng)面優(yōu)化過后的單寧酶固體發(fā)酵培養(yǎng)基和培養(yǎng)條件為：茶葉4.5 g,單寧酸0.5 g,α-乳糖0.25g,無機鹽溶液(1.070% NH4Cl,4.1%(w/w)MgSO4·7H2O,0.1% NaCl, pH 6.057)9.45 mL,接種量2.0 mL,28℃發(fā)酵96h。最佳發(fā)酵酶活的預(yù)測值為31.28962 U/gds.實測值為30.37 U/gds。同優(yōu)化前產(chǎn)率10.42 U/gds相比,提高到了約2.91倍。利用菌株MP-24固體發(fā)酵產(chǎn)生的單寧酶對茶多酚進行生物轉(zhuǎn)化,發(fā)現(xiàn)其對茶湯轉(zhuǎn)溶效果顯著,明顯提高茶湯澄清度。用HPLC方法和LC-MS分析方法分析其轉(zhuǎn)化產(chǎn)物,之后用抗超氧陰離子自由基的測定、羥自由基測定、DPPH自由基清除率的測定和總抗氧化能力(T-AOC)測定等4種抗氧化活性分析方法分析其轉(zhuǎn)化產(chǎn)物的抗氧化活性,經(jīng)過生物轉(zhuǎn)化的茶湯和茶多酚的抗氧化活性有一定程度的提高。本研究鑒定了一株從黑茶中分離篩選的產(chǎn)單寧酶菌株MP-24,優(yōu)化了其固體培養(yǎng)基與培養(yǎng)條件,明確了MP-24所產(chǎn)單寧酶對茶多酚有一定的轉(zhuǎn)化作用,并可提高茶湯的澄清度與抗氧化活性。本研究的結(jié)果為單寧酶的生產(chǎn)和應(yīng)用提供了理論參考和基礎(chǔ)。
[Abstract]:Tannase (E.C.3.1.1.20) can hydrolyze ester bond in tannic acid and completely hydrolyze tannic acid into Gallic acid and glucose. Tannase is widely used in food, feed, pharmaceutical, beverage, brewing and chemical industries. In this study, the tannase producing strain MP-24 was preliminarily identified, its solid fermentation medium formulation and fermentation conditions were optimized, and applied to the biotransformation of tea polyphenols and tea soup. HPLC and LC-MS analysis were used to analyze the transforming products of tannase. The antioxidant activity of the transformed product was determined. The strain MP-24 was identified as Penicillium (Penicillium) after morphological observation and ITS sequence analysis. The formula and culture method of solid fermentation medium for producing tannase by solid fermentation of the strain were optimized by single factor-response surface, and the culture conditions were as follows: tea 4.5 g, tannic acid 0.5 g, 偽 -lactose 0.25 g, tea 4.5 g, tannin 0.5 g, 偽 -lactose 0.25 g. Inorganic salt solution (1.070% NH4Cl,4.1% (w / w) MgSO4 7H 2O 0.1% NaCl, pH 6.057) was inoculated with 9.45 mL, for 96 h at 2.0 mL,28 鈩，
本文編號：2260671
[Abstract]:Tannase (E.C.3.1.1.20) can hydrolyze ester bond in tannic acid and completely hydrolyze tannic acid into Gallic acid and glucose. Tannase is widely used in food, feed, pharmaceutical, beverage, brewing and chemical industries. In this study, the tannase producing strain MP-24 was preliminarily identified, its solid fermentation medium formulation and fermentation conditions were optimized, and applied to the biotransformation of tea polyphenols and tea soup. HPLC and LC-MS analysis were used to analyze the transforming products of tannase. The antioxidant activity of the transformed product was determined. The strain MP-24 was identified as Penicillium (Penicillium) after morphological observation and ITS sequence analysis. The formula and culture method of solid fermentation medium for producing tannase by solid fermentation of the strain were optimized by single factor-response surface, and the culture conditions were as follows: tea 4.5 g, tannic acid 0.5 g, 偽 -lactose 0.25 g, tea 4.5 g, tannin 0.5 g, 偽 -lactose 0.25 g. Inorganic salt solution (1.070% NH4Cl,4.1% (w / w) MgSO4 7H 2O 0.1% NaCl, pH 6.057) was inoculated with 9.45 mL, for 96 h at 2.0 mL,28 鈩，
本文編號：2260671
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