2019 ASHS Annual Conference

Green tea has been utilized in Oriental countries as well as Europe and United States due to its highly potential health benefits. Recently, green tea has received increased attention since people are aware of personal health and environment. Green tea is a very rich source of polyphenols and the major phenolic compounds are catechins like catechin (C), epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC) and epigallocatechin gallate (EGCG). Besides the contribution of catechins to tea taste, important pharmacological properties have been associated to their consumption, including antioxidant, anticancer, anti-inflammatory, anti-hypercholesterolemic activity, and especially anti-obesity effect. In this study, five green tea cultivars (Chamnok and Bohyang, Yabu, Hushun, and native) were evaluated their catechin profiles by C18 reverse-phase HPLC analysis and anti-obesity effect through α-glucosidase and HMG-CoA enzyme inhibition. Green tea varieties had 10~18% total catechins which accounted for 54~75% of EGCG and ECG. Among samples, domestic tea varieties, Chamnok, and Bohyang showed 11~14% or 20~24% higher amounts of total catechins and EGCG, compared to others. In addition, Chamnok green tea had the highest amount of caffeine and catechchin (EGCG and ECG) contents among green tea varieties. There were remarkable differences in the catechins contents according to different harvest periods. Fall tea leave contained the highest amount of catechins (200~250 mg/g DW) while spring teal leave did catechins (80~120 mg/g DW) content at samples. For anti-obesity effect, Chamnok green tea showed 1.7 times higher a-glucosidase inhibition and 2.5 times stronger repression on HMG-CoA enzyme, resulting in cholesterol synthesis, compared to other cultivars. Overall, those results indicate that domestic tea varieties, especially Chamnok contained higher catechins and stronger anti-obesity effects than other imported tea cultivars. ±This study was financially supported by Rural Development Administration (Project No. PJ012565).

Key words; Green tea, cultivars, catechins, anti-obesity