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ThesisItem Open Access Screening of tea cultivars grown in Kumaon region for their total phenolics, pigments and individual catechin contents(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-08) Pandey, Sudhanshu; Mishra, D.P.Total chlorophylls, chlorophyll a , chlorophyll b, total carotenoids and total phenolics contents and HPLC profiling of various catechins and quantitative estimation of (-)EGCG,(-)EC and (-)ECG were carried out in fresh tea leaf leaves (dried immediately after sampling), of 6 varieties grown in Kumaon region and a black orthodox tea sample processed locally. The main objective of the study was to screen these varieties for their catechin contents and other flavanoid constituents. Dried leaf powder was used to estimate chlorophylls, carotenoids and total phenols. For catechins, dried leaf powder was first extracted with aqueous methanol. This extract was subjected to separation of catechins on HPLC and identification and quantitative estimation were done using standard catechins. Contents of various parameters were variable among varieties and there was no set pattern. Kangra Jat had highest content of chlorophyll a, and total carotenoids while chlorophyll b, total chlorophyll and total phenols were highest in UPAS1-9. T-78 exhibited lowest content of all these parameters. Black orthodox tea had pretty high content of chlorophylls and carotenoids but its phenolics content was lowest, perhaps due to oxidation of phenolics during processing. The HPLC profiles gave eight peaks, out of which first two peak, were probably of some non-catechin compounds, hence ignored. Out of remaining 6 peaks, 3 were of (-)EGCG,(-)EC and (-)ECG. Other three were named as U1, U2 and U3.Out of them U1 was supported to be (-)EGC. By comparison of peak areas,retention times etc., quantitative estimation of (-)EGCG, (-)EC and (-)EC was performed, which revealed these three catechins comprised nearly 0.11-0.14% of dried solids (110-140 mg g-1) and (-)EGCG was nearly (69-82 mg g-1),half of all catechins estimated. On the basis of increasing catechin contents, order of varieties was: Black Orthodox tea(commercial)