Evaluation of antioxidant and cytotoxic activity of herbal teas from Western Himalayan region: a comparison with green tea (Camellia sinensis) and black tea

Background: Herbal tea, known as health-promoting due to its therapeutic potential for several ailments and consumption increased over decades. The Western Himalayan region of India affluent with herbs has therapeutic values. However, these herbs have not been used in the tea and are still untouched by mankind. Therefore, the present study aimed to pioneer and manufacture herbal teas from Western Himalayan region plants. Results: Our findings showed that total polyphenol content was ranged from 4.42 +/- 0.53 to 13.37 +/- 0.50% compared to green tea (GT) and black tea (BT) (13.37 +/- 0.50 and 10.05 +/- 0.11%) of C. sinensis, total flavonoid and total catechin content was ranged from 1.81 +/- 0.67-4.68 +/- 0.26% to 4.43 +/- 0.28-15.17 +/- 0.53% in all the herbal tea samples. Moreover, antioxidant activity was ranged in DPPH from (27.58-226.28 mu g/mL) and in ABTS (14.17-117.62 mu g/mL). Highest antioxidant activity was observed in GT and lowest was observed in rose tea (RT). Heatmap was made for catechin visualization in green herbal teas (GHT). Principal Component Analysis (PCA) showed the variation of amino acids in all the herbal tea samples which was found in the range from 0.82 to 2.86%. Taxus green tea (TGT) exhibited remarkable cytotoxic activity against SW480 (50.9 +/- 0.7 at 200 mu g/mL). Whereas, sea-buckthorn green tea (SGT) exhibited the highest activities on A549 cells (87.01 +/- 1.1 at 200 mu g/mL). Maximum volatile organic compounds (VOCs) were identified in lemongrass black tea (LBT) (96.23%), namely, geranial, levoverbenone, pulegone, L-linalool and cineol. In addition, the sensory analysis revealed that herbal tea shows sweet and better taste with high sensory attributes. Conclusions: Current study revealed that the Western Himalayan region plants could be used as herbal tea with additional health benefits. The prepared herbal teas can be used in nutraceuticals as a beverage and a new dietary source for bioactive compounds.