February 25/Agriculture Business Week -- According to a study from Kunming, China, "Camellia crassicolumna var. multiplex (Chang et Tan) Ming belonging to Camellia sect. Thea (Theaceae), is endemic to the southeastern area of Yunnan province, China, where the leaves have been commonly used for making tea and beverages consumed widely."
"HPLC analysis showed that there was no caffeine or theophylline contained in the leaves; however, thin layer chromatography (TLC) analysis suggested the abundant existence of phenolic compounds. Further detailed chemical investigation of the green tea produced from the leaves of the plant led to the identification of 18 phenolic compounds, including four flavanols (1-4), six flavonol glycosides (5-10), three hydrolyzable tannins (11-13), two chlorogenic acid derivatives (114, 15) and three simple phenolic compounds (16-18). The isolated compounds were evaluated for their antioxidant activities by 1,1'diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and tyrosinase inhibitory assays. Most of them exhibited significant DPPH radical scavenging activities, whereas flavanols and hydrolyzable tannins showed stronger inhibitory activities on tyrosinase," wrote Q. Liu and colleagues.
The researchers concluded, "The results suggest that C. crassicolumna could be an ideal plant resource for a noncaffeine beverage."
Liu and colleagues published the results of their research in the Journal of Agricultural and Food Chemistry ("Phenolic Antioxidants from Green Tea Produced from Camellia crassicolumna Var. multiplex." Journal of Agricultural and Food Chemistry, 2009;57(2):586-590).
For additional information, contact Y.J. Zhang, Chinese Academy Science, Kunming Institute Botany, State Key Laboratory Phytochem & Plant Resources W China, Kunming 650204, People's Republic of China.
From the February 16, 2009, Prepared Foods E-dition
