香檬皮經不同方式萃取後其消化酵素及糖化終產物之抑制能力

隨著現代人生活習慣的改變，肥胖已成為全球重要的公衛議題。消化酵素的作用造成多餘的熱量被吸收，而體內的血糖與蛋白結合導致糖化終產物 (Advanced glycation end products, AGEs) 的攝入增加，許多研究顯示糖化終產物與人體的老化及慢性疾病息息相關，因此如何抑制其生成是十分重要的議題。香檬(Citrus depressa Hayata)是一種柑橘水果，文獻指出其具有抗氧化、抗炎、抗癌、抗肥胖、抗高血糖、神經保護等特性，本研究使用果汁加工中剩餘的香檬皮副產物，並比較超音波、酵素水解、高壓靜電場三種萃取方式的樣品其抑制消化酵素及抑制糖化終產物生成能力。實驗結果顯示，A 溶劑樣品在脂肪酶活性及糖化終產物生成能力方面皆有 80%以上的抑制率，因此作為後續實驗的最佳萃取方式；三種萃取方式中，總酚及總類黃酮含量以酵素水解之樣品最高，分別約 2500 mgGAE/100 g 及 400 mgQE/100 g；FRAP 三價鐵還原能力約為 1600 μmol /L，三者沒有顯著差異。DPPH 自由基清除率結果超音波樣品與高壓靜電場樣品間未有顯著差異，兩者略高於酵素水解樣品。三種萃取方式的脂肪酶抑制能力皆有不錯的效果，抑制率約 89~91%間，抗糖化能力則是高壓靜電場及酵素水解效果較好，約在 87~91%間。此外，進一步分析三種樣品中之酚類化合物組成，含量較多的酚酸為七葉樹(Esculetin)、 3,4-二羥基苯甲酸 (3,4-dihydroxybenzoic acid) 及兒茶素 (Catechin)，類黃酮則是川陳皮素 (Nobiletin) 及橙皮苷 (Hesperidin) 為主。綜合以上結果，因此認為高壓靜電場對於萃取香檬皮內的抑制消化酵素成分和提升抗糖化能力是有幫助的。

關鍵字

香檬；消化酵素；糖化終產物；高壓靜電場

並列摘要

With the change of modern people's lifestyle, obesity has become an important public health issue worldwide. The action of digestive enzymes leads to the absorption of excess calories, and the binding of blood sugar with protein in the body causes an increase about the intake of advanced glycation end products (AGEs). Many studies have shown that AGEs are closely related to human body aging and chronic diseases, therefore, it’s an important issue for how to inhibit the production of AGEs. Citrus depressa Hayata is a type of citrus fruit, which has been reported in some literature to possess anti-oxidant, anti-inflammatory, anti-cancer, anti-obesity, anti-hyperglycemic, neuroprotective and other properties. In this study, Citrus depressa Hayata peel by-products from fruit juice processing were used, and three extraction methods, such as ultrasonic, enzyme hydrolysis, and high-voltage electrostatic field (HVEF) were used to compare the ability to inhibit digestive enzymes and the formation of AGEs. The results of the experiments showed that the A-extracted sample has an inhibition rate more than 80% in terms of lipase activity and the ability of AGEs generation, so it is considered as the best extraction solvent for further experiments. Among the three extraction methods, the content of total phenols and total flavonoids were found highest in the sample of enzymatic hydrolysis (approximately 2500 mgGAE/100 g and 400 mgQE/100 g, respectively). For the ferric reducing antioxidant power (FRAP, about 1600 μmol/L approximately), there is no significant differences among the three different extracted samples. For the DPPH free radical scavenging activity, it turned out that there's no significant difference between the samples extracted through ultrasonic and HVEF, whereas both of them showed slightly higher value than the enzyme hydrolysis sample. All extraction methods showed good results on the lipase inhibition ability,with inhibition rate about 89-91%; for anti-glycation ability, it were better in samples extracted through HVEF and enzyme hydrolysis, for about 87-91%. In addition, the composition of phenolic compounds in the three samples was further analyzed by HPLC. The most abundant phenolic acids were esculetin, 3,4-dihydroxybenzoic acid and catechin, and the flavonoids were mainly nobiletin and hesperidin. Based on the above results, it is considered that the HVEF is helpful for extracting the components which could inhibit digestive enzymes and improve the anti glycation ability in the Citrus depressa Hayata peel