Antioxidative activities and the chemical constituents of two Chinese teas, Camellia kucha and C. ptilophylla

Abstract

Summary Two kinds of green tea were prepared with the young shoots of Camellia kucha and C. ptilophylla, and antioxidative activities of the chemical constituents were determined. Levels of alkaloids, catechins, total polyphenols, flavonoids and amino acids were determined by high‐performance liquid chromatography and UV‐Vis spectrophotometer. Antioxidative activity was evaluated by applying 2,2‐diphenyl‐1‐picrylhydrazyl radical assay and ferric reducing antioxidant power assay. Our results showed that theobromine was the only alkaloid in C. ptilophylla, while there was theacrine in C. kucha, which was coexisting with the caffeine. We confirmed the high content of (−)‐gallocatechin gallate in C. ptilophylla was not the epimerisation of (−)‐epigallocatechin gallate during the heating procedure. These wild teas had higher content of tea polyphenols, water extracts, amion acids and stronger antioxidative activity compared with the longjing tea. They could be used for the development of noncaffeine beverages and new types of tea.

Antioxidant effects of rosemary extracts on sunflower oil compared with synthetic antioxidants

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Preparative separation of gallocatechin gallate from Camellia ptilophylla using macroporous resins followed by sephadex LH-20 column chromatography

“…It is important to develop a simple and efficient method to extract these compounds. In our present study, a column-chromatographic method was applied to extract the bioactive compounds just with water [39,40]. As shown in Fig.…”

“…PA, USA) and a HT-230A column heater (Heng'ao, Tianjin, China) [40]. Separation was performed using a reversed-phase Discovery RP-Amide C16 guard column (250 mm × 4.6 mm, 5 m).…”

Subacute oral toxicity of cocoa tea (Camellia ptilophylla) water extract in SD rats

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