کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1190791 963539 2007 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Antioxidant activity of various extracts of old tea leaves and black tea wastes (Camellia sinensis L.)
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Antioxidant activity of various extracts of old tea leaves and black tea wastes (Camellia sinensis L.)
چکیده انگلیسی

The antioxidant activity of various extracts of old tea leaves (OTL) and black tea wastes (BTW) in comparison with that of green tea leaves (GTL) was evaluated. The highest extraction yield and antioxidant activity were found in hot water extracts of GTL. Hot water extracts of OTL and BTW showed the same statistically significant antioxidant activities (P < 0.05). Also, there was no statistically significant difference between the antioxidant activities of OTL and BTW extracts obtained by the other two extraction methods (ethyl acetate and methanolic methods) and, in some cases, BTW extracts acted even better than OTL extracts. The antioxidant activity of tea extracts was not concomitant with the development of their reducing power. This suggested that the antioxidant activity of tea extracts likely involves other mechanisms in addition to those of reductones. Totally, BTW extracts had antioxidant activities comparable with or even better than those of OTL extracts. Hence, OTL and BTW, which are often considered as agricultural wastes, can be used as potent natural antioxidative sources.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Food Chemistry - Volume 100, Issue 1, 2007, Pages 231–236
نویسندگان
, , ,