柚子（Citrus grandis ）是東南亞地區重要經濟價值的土產作物之一。柚子皮的重量佔據了柚子總果重的30%，但是由於它們在營養價值上尚未被挖掘出來，因此常被當作廢棄物拋棄。本研究的目的主要是為了要確定柚子全果皮、 外果皮和中果皮對降血糖活性和抗氧化活性上的可能性 。在研究中，使用八裡麻豆文旦柚皮（全果皮、 外果皮和中果皮）是以熱水萃取或80% 乙醇萃取的方式得到萃取物。在六個實驗樣品的結果中得知，80%乙醇萃取外果皮萃取物對降血糖及抗氧化活性的效果最好。結果 ：α-葡萄糖苷酶活性抑制的IC50：25.12 mg/mL，總酚類化合物（TPC）：79.73 mg GAE / g，還原力：261.37 mg Vit.C/g sample，DPPH自由基清除率IC50：8.82 mg/mL和ABTS自由基清除率IC50：0.59 mg/mL 。
Pomelo（Citrus grandis）is a native fruit of great economic importance in Southeast Asia . The peels of pomelo account for 30% of the fruit weight but they has been dumped without knowing their contribution in nutrition values . The aim of the study was to determine the hypoglycemic potential and antioxidation activities of citrus grandis whole peel, mesocarp and exocarp. Pomelo peels (whole peels, mesocarp, and exocarp) were extracted with hot water or 80% ethanol. Among the six examined samples, 80% ethanol extracted, exocarp showed the best results in terms of hypoglycemic effect and antioxidation activity. It was characterized by IC50 value of 25.12 mg/mL for α- glucosidase inhibitor , total phenolic compound ( TPC ) : 79.73 mg GAE / g sample, reducing power : 261.37 mg Vit.C/g sample, DPPH free radical scavenging rate IC50 : 8.82 mg/mL and ABTS free radical scavenging rate IC50 : 0.59 mg/mL .
A high correlation was observed between total phenolic contents and anti -α-glucosidase activity. The obtained result suggest a potential use of pomelo peels as valuables source for the development of functional food or nutraceutical product.
