**4.6 Other applications of tea phytochemicals**


Consumption of tea has other several promising-health benefits such as it decrease the risk of hypertension [58], lowers the risk of osteoporosis, protects

#### **Table 4.**

*Effect of green tea on photoaging, stress resistance, neuroprotection and associated health complications: in vivo studies [67].*


#### **Table 5.**

*Effect of green tea on photoaging, stress resistance, neuroprotection and associated health complications: Clinical trials [67].*

against the risk of hip fractures [59, 60], improves the metabolic activity of the bacteria in intestinal tract [61].

The bioactive compounds in oolong tea such as polyphenol, caffeine have the antistress and antioxidant activities which can prevent the diseases related to stress [62]. The green tea catechin, EGCG is useful in inhibition of HIV infection and HIV-1 replication and multi-drug resistant *Staphylococcus aureus* infections [63]. Tea also shows antifungal activity which is higher in black tea followed by green tea and white tea [64]. Black is also effective in asthma disease which is ascribed by the antihistaminic and anti-inflammatory activities of the flavonol glycosides contained in black tea [65]. Tea extract also shows antiallergic activity by suppressing histamine activity controlling the allergic response including inflammation, urticaria, mastocytosis, asthma, and dermatitis [66].

Some other beneficial effects of the constituents are antiaging, stress control, ant-bacterial, anti-viral, and useful in Parkinson's disease, Alzheimer's disease etc. Recently, Tencomnao et al. [67] discussed the results of some *in vivo* studies on the effects of green tea supplements on various health benefits such photoaging, stress resistance, neuroprotection, and associated health complications and some of these are outlined in **Table 4**. Some of the major clinical trials on these various health benefits are depicted in **Table 5**.

#### **5. Conclusions**

This chapter discusses the nutraceutical properties of bioactive compounds in tea in particular polyphenols and their role in health benefits. The catechins in tea viz. EGCG, EGC, ECG and EC have therapeutic properties such as antioxidant, antidiabetic, anti-microbial, anti-inflammatory as well as anti-cancer properties. The black tea polyphenols the flavins and thearubigins also show many profound therapeutic values. In addition, oolong tea and white tea are also pharmacologically important. Therefore, consumption of tea in its various form viz. green tea, black tea, oolong tea and other food products with tea as active ingredient have been increased now a days. There are many more food products with tea and or its extracted components as additive have been developed which includes instant tea beverage, confections, cereal bars, pet foods etc. Considering the growing interest

*Nutraceuticals of Tea* (Camellia sinensis) *for Human Health DOI: http://dx.doi.org/10.5772/intechopen.96506*

in nutraceuticals due to their several health values, the aim of the present chapter is to outline the nutraceutical potential of phytochemicals of tea with their known therapeutic properties. Due to their ready bioavailability, the possibilities of using nutraceuticals from tea as natural healers in treatment and prevention of diseases have been explored.
