柚苷酶對柑桔Flavanone-Glycoside水解之研究(1)：柚苷酶分解柚苷與柑果苷之活性

Studies on the Enzymatic Hydrolysis of Citrus Flavanone-Glycoside by Naringinase (1) Naringin-and Hesperidin-Decomposition Activities of Sclase and Naringinase AO.

臺灣產之柚果中所含之主要Flavanone-glycoside經本試驗之抽取、分離、檢定之結果，被確認為柚苷（Naringin），其構造式應為Naringenin-7-rhamnoglucoside，為苦味之主要成份，亦為柚果不能普遍供給加工製造之主要原因，但此種苦味物質可由某些微菌之酵素予以分解，本試驗即據此採用Sclase及Naringinase AO二種酵素劑加以試驗，結果認為：（1）酵素對柚苷不同濃度之作用國經研究認為以0.1%使用濃度柚苷，若用0.1%之酵素乾粉末，則可達到相當高之分解率。（2）酵素活性最適宜之作用條件為Sclase在pH4.0，50℃，而Naringinase AO則在pH5.0，50℃。（3）若pH降低至2~3，或高達6~8，二種酵素之活性均劇急的降下，同時發現於68℃以上加熱二小時二種酵素則呈不活動性。（4）利用0.1% Sclase對含0.05%柑果苷之作用液中在50℃，pH 4.5經2小時後幾將全數之柑果苷分解成為hesperetin及糖，但若採用另一種酵素Naringinase AO則不能達到此目的。

Naringin, or naringedin-7-rhamnoglucoside, has been found as the main flavanone-glycoside in the pomelo fruit in Taiwan, after extracted, isolated and identified by this paper. This bitter substance has made a considerable trouble for the fruit processing purpose In order to utilize the enzymes from mold for debittering of naringin and decomposing of hesperidin, an investigation on the activity of sclase and naringinase AO those prepared by the Sankyo Inc. of Japan was carried out. The results are as follows: (1) The remarkable activity of those two enzymes with different concentration of naringin as substrate was studied and the optimum concentration was found with 0.1% of naringin and also 01% of dried enzyme powder. (2) The optimum condition for enzymatic activity was found at pH4.0-5.0 50℃ for sciase, or pH 50-60, 60℃ for naringinase AO. (3) The activity should be decreased sharpely when the substrate solution of pH 2-3 or pH 6-8 was supplied f or those two enzymes. It also found that two nariegin-decomposed enzymes may be inactivated when heated up to 5℃ or more within two hours. (4) Hesperidin can be decomposed into hesperetin and sugar by sclase with a high degradation ratio in the region of pH 4.5, at 50°C for 2 hrs, but it was failed to decompose naringin by the another enzyme, naringinase AO.