Annual Report - IHBT

CSIR-IHBT Annual Report 2010-11Decaffeination of Kangra orthodox teaKangra orthodox tea was decaffeinated at different extraction temperatures (35, 60 and 85°C) andpressures (90 and 170 bar) using a Thar Supercritical Extraction System. Highest decaffeinationwas obtained at 35°C and 170 bar and least decaffeination was obtained at 35°C and 90 bar.Decaffeinated tea recorded highest loss in theaflavins, total colour and brightness of the infusion. Inflavour components, decrease in aldehydes (2-hexenal), hydrocarbons (limonene oxide), pyrazines(2,5-dimethyl pyrazine) and esters (methyl salicylate and hexyl hexanoate) responsible for thetypical Kangra note was observed.Bioprospecting Himalayan bioresource through transgenic and nutraceurticaltechnologies (Funded by Department of Biotchnology, Govt of India)In a separate study, purified mixtures of 5 flavanols from tea and 3 flavones from hippophaewere mixed in different proportions to prepare nutraceuticals. Highest antioxidant activity wasrecorded when flavonoids from hippophae and tea were mixed in 40:60 ratio (Table 13).Table 13 Antioxidant activity of nutraceutical preparationsType of extraction DPPH (%) FRAP (µm/l)Hippophae (H) 85.2 7788.0Tea (T) 86.0 8631.0(H+T) 80:20 82.6 14920.5(H+T) 60:40 83.5 14918.0(H+T) 50:50 83.7 15655.5(H+T) 40:60 86.4 15865.5(H+T) 20:80 84.2 14448.0Extraction and purification ofsaponins from Kangra tea seedsThe tea is propagated vegetatively andits seeds are rarely used for replanting.In a new activity, work was initiated toisolate and purify saponins from seeds.Four saponins (S 1-S 4) were isolatedand characterized (Fig. 41). Thesesaponins showed high activity againstthe dermatophytic fungus, Trichophytonrubrum that causes ringworm andathletes foot.Fig. 41 Structure of saponins isolated from tea seeds45