Journal of Food and Nutrition Research
ISSN (Print): 2333-1119 ISSN (Online): 2333-1240 Website: Editor-in-chief: Prabhat Kumar Mandal
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Journal of Food and Nutrition Research. 2014, 2(9), 652-658
DOI: 10.12691/jfnr-2-9-20
Open AccessArticle

A Comparative Study on Antioxidant Activity and Inhibitory Potential against Key Enzymes Related to Type 2 Diabetes of Four Typical Teas

Dedong Kong1, Jing Wu2, Shili Sun3, Yuefei Wang2 and Ping Xu1, 2,

1Agricultural Experiment Station of Zhejiang University, Hangzhou, China

2Department of Tea Science, Zhejiang University, Hangzhou, China

3Drinkable Plants Institute (Tea Research Center ), Guangdong Provincial Key Laboratory of Tea Plant Resources Innovation and Utilization, Guangzhou, China

Pub. Date: September 16, 2014

Cite this paper:
Dedong Kong, Jing Wu, Shili Sun, Yuefei Wang and Ping Xu. A Comparative Study on Antioxidant Activity and Inhibitory Potential against Key Enzymes Related to Type 2 Diabetes of Four Typical Teas. Journal of Food and Nutrition Research. 2014; 2(9):652-658. doi: 10.12691/jfnr-2-9-20


Tea (Camellia sinensis L.) is categorized into four types depending on the degree of fermentation, which in turn affects the physicochemical properties of tea. In this work, aqueous extracts of four typical teas, named green tea, oolong tea, black tea and puerh tea, were obtained, and their chemical compositions and bioactivities including antioxidant activity and inhibition on α-amylase and α-glycosidase were compared. It was found oolong and green tea not only possessed stronger antioxidant ability in assays of DPPH, ABTS and FRAP, but also had more power on inhibition on α-amylase and α-glycosidase. Pearson correlation analysis showed tea polyphenols and catechins had significant positive correlations on α-amylase inhibition. However, caffeine was observed to have a significant negative effect on α-glycosidase inhibition. These results indicated teas with no or slight fermentation (decaffeinated was better), were suitable for diabetes.

tea fermentation antioxidant activity hyperglycemia decaffeinated

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