利用液相層析法偵測以酵素去除葡萄柚汁苦味的過程   全文下載

Monitoring Enzymatic Debittering in Grapefruit Juice by High Performance Liquid Chromatography

本研究發展一液相層析方法，用以同時偵測酵素去除葡萄柚汁苦味的過程中，柚苦?（naringin）及其水解產物洋夸?（prunin）、柚苦素（naringenin）等黃烷酮物質的含量變化，並可估算去苦味酵素的效率。葡萄柚汁樣品經添加無水酒精改變極性後，再經離心及過濾步驟製備，層析分離於逆相碳十八管柱以及含30%氰甲烷水溶液之動相完成。三種黃烷酮之回收率均大於88%而定量線性範圍介於20 - 500 μg／mL。此法可觀察葡萄柚汁去苦味過程中，α-L-rhamnosidase 將柚苦?水解為洋夸?，以及β-D-glucosidase 將洋夸?水解為柚苦素的變化，也可用來分別估算去苦味酵素α-L-rhamnosidase 及β-D-glucosidase 的水解效率，因此適於日後葡萄柚汁工業化去苦味的應用。

An HPLC method was developed for monitoring the progress of enzymatic debittering and estimating the efficiency of debitter enzymes by means of simultaneously determining the levels of the bitter flavanone naringin, its hydrolytic intermediate prunin and the tasteless product naringenin in grapefruit juice. The sample preparation was carried out by a polarity modification with anhydrous ethanol, a centrifuge step and a 0.45 μm filtration. Separation was achieved using a reverse phase C-18 column with a mobile phase comprising 30 % acetonitrile. The average recovery rates were above 88 % and the quantitative linearity ranged from 20 - 500 μg/mL for the flavanones analyzed. The conversions of naringin to prunin by α-L-rhamnosidase and prunin to naringenin by β-D-glucosidase in grapefruit juice were monitored, and the efficiency of the individual enzyme was separately evaluated. Applicability of this method in juice processing is also discussed. 本研究發展一液相層析方法，用以同時偵測酵素去除葡萄柚汁苦味的過程中，柚苦苷（naringin）及其水解產物洋夸苷（prunin）、柚苦素（naringenin）等黃烷酮物質的含量變化，並可估算去苦味酵素的效率。葡萄柚汁樣品經添加無水酒精改變極性後，再經離心及過濾步驟製備，層析分離於逆相碳十八管柱以及含30%氰甲烷水溶液之動相完成。三種黃烷酮之回收率均大於88%而定量線性範圍介於20 - 500 μg／mL。此法可觀察葡萄柚汁去苦味過程中，α-L-rhamnosidase 將柚苦苷水解為洋夸苷，以及β-D-glucosidase 將洋夸苷水解為柚苦素的變化，也可用來分別估算去苦味酵素α-L-rhamnosidase 及β-D-glucosidase 的水解效率，因此適於日後葡萄柚汁工業化去苦味的應用。