Page 54 - 2010-11.pdf

CSIR-IHBT Annual Report 2010-11

Decaffeination of Kangra orthodox tea

Kangra orthodox tea was decaffeinated at different extraction temperatures (35, 60 and 85°C) and
pressures (90 and 170 bar) using a Thar Supercritical Extraction System. Highest decaffeination
was 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. In
flavour components, decrease in aldehydes (2-hexenal), hydrocarbons (limonene oxide), pyrazines
(2,5-dimethyl pyrazine) and esters (methyl salicylate and hexyl hexanoate) responsible for the
typical Kangra note was observed.

Bioprospecting Himalayan bioresource through transgenic and nutraceurtical
technologies (Funded by Department of Biotchnology, Govt of India)

In a separate study, purified mixtures of 5 flavanols from tea and 3 flavones from hippophae
were mixed in different proportions to prepare nutraceuticals. Highest antioxidant activity was
recorded when flavonoids from hippophae and tea were mixed in 40:60 ratio (Table 13).

Table 13 Antioxidant activity of nutraceutical preparations

Type of extraction DPPH (%) FRAP (µm/l)
Hippophae (H) 85.2 7788.0
Tea (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 14448.0

Extraction and purification of Fig. 41 Structure of saponins isolated from tea seeds
saponins from Kangra tea seeds

The tea is propagated vegetatively and
its seeds are rarely used for replanting.
In a new activity, work was initiated to
isolate and purify saponins from seeds.
Four saponins (S1-S4) were isolated
and characterized (Fig. 41). These
saponins showed high activity against
the dermatophytic fungus, Trichophyton
rubrum that causes ringworm and
athletes foot.

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