Effect Of Exogenous Enzymes On The Vanillin From Extract Of Green Vanilla

Vanilla plannilia Andrews is a rare tropical spice plant. In present, not only the fermentation period of vanilla production is long, but also the conversion rate of glucovanillin and the content of vanillin are both low, which lead to high processing cost of vanilla. Therefore, this research attempts to hydrolyse vanilla bean by using a variety of enzymes including cellulase, pectinase and beta glycosidase enzymes. Main variables which were of significance for the vanillin content were studied and a central composite design (CCD) based on the results of a single-factors tests was used. Response surface methodology based on CCD was employed to optimize the enzyme process for maximum vanillin production. This will provide one method to produce natural vanillin from vanilla pod on the premise of cost.(1) Three main variables, including cellulase amount, reaction temperature, and time which were of significance for the vanillin content were studied and a central composite design (CCD) based on the results of a single-factor tests was used when Vanilla plannilia Andrews was used as the raw materials. Response surface methodology based on CCD was employed to optimize the combination of enzyme amount, reaction temperature, and time, for maximum vanillin production. This resulted in the optimal condition in regards of the enzyme amount, reaction temperature, and time at26.9mg (40.35U/g),53?, and16h, respectively. Under the optimal condition, the experimental yield of vanillin was2.18%(dwb). Compared to the traditional curing process (1.97%), the optimized method for the vanillin production significantly increased the yield by0.21%.(2) Four main variables, including enzyme amount, reaction temperature, time and pH, which were of significance for the vanillin content were studied and a central composite design (CCD) based on the results of a single-factor tests was used. Response surface methodology based on CCD was employed to optimize the combination of enzyme amount, reaction temperature, time, and pH for maximum vanillin production. This resulted in the optimal condition in regards of the enzyme amount, reaction temperature, time, and pH at84mg (252.00U/g),50?,7.1h, and4.2, respectively. Under the optimal condition, the experimental yield of vanillin was4.62%±0.14%(dwb), which was in good agreement with the value predicted by the model. Compared to the traditional curing process (1.97%) and viscozyme extract (2.36%), the optimized method for the vanillin production significantly increased the yield by2.65%and2.26%, respectively. (3) The effect of ?-glucosidase on vanillin content from vanilla pods was studied. The optimal conditionswere enzyme amount5.3U(0.53U/g), reaction temperature40?, reaction time2.0h,and pH6.5, which lead to5.71%vanillin content(dwb). Compared to the traditional curing process (1.97%), the optimized method for the vanillin production significantly increased the yield by3.74%.(4) The effect of the ultrasonic pretreatment combined with adding cellulase and pectinase on the vanillin content in vanilla bean extract were investigated. The results showed that the content of vanillin in green vanilla were2.61%and4.91%, after ultrasonic (ultrasonic power400W,20min)pretreatment assisted with cellulose in its optimal process conditions, and pectinase in its optimal process conditions, respectively. Compared to the unultrasonic pretreatment, the optimized method for the vanillin production significantly increased the yield by0.43%and0.29%, respectively.(5) On the basis of single factor experiment, the cellulose-pectinase, cellulose-beta glycosidase, pectinase-beta glycosidase enzymes were used to investigate the effect of their combination on the vanillin content. The results showed that the pectinase-beta glycosidase could acquired the highest content(5.88%,dry weight,847.72mg/mL)...