@article {77, title = {Antilithogenic Potential of Green Tea, Oolong Tea, and Black Tea}, journal = {Pharmacognosy Research}, volume = {12}, year = {2020}, month = {February 2020}, pages = {92-94}, type = {Short Communication}, chapter = {92}, abstract = {

Background: Urolithiasis and nephrolithiasis are the commonly occurring painful diseases in most parts of the world. The number of new cases associated with lithiasis is on rise, although various therapies such as percutaneous nephrolithotomy, lithotripsy, and other surgical procedures can remove the stones, high recurrence rate is a major problem. Objectives: The present study was undertaken to evaluate the antilithogenic potential of green tea, oolong tea, and black tea employing chemical model. Materials and Methods: The antilithogenic action of different teas on calcium oxalate crystal formation was investigated on artificial urine spectroscopically, and the modulation of crystal size and density was recorded microscopically. Results: The different tea types showed significant inhibitory action on nucleation and crystal size morphology and density. The optical and spectroscopic techniques demonstrated that standard drug cystone exhibited highest inhibition followed by green tea, oolong tea, and black tea. Conclusion: Green tea illustrated maximum antilithogenic property as compared to other tea types and can be used as a potential dietary agent for the prevention of lithiasis.

}, keywords = {Antilithogenic, Black tea, Cystone, Green tea, Nephrolithiasis, Oolong tea, Urolithiasis}, doi = {10.4103/pr.pr_67_19}, author = {Shaikh I Nasrul and Amit Sehgal} } @article {677, title = {Black Tea (Camellia sinensis) Decoction Shows Immunomodulatory Properties on an Experimental Animal Model and in Human Peripheral Mononuclear Cells}, journal = {Pharmacognosy Research}, volume = {4}, year = {2012}, month = {december,2011}, pages = {15-21}, type = {Original Article}, chapter = {15}, abstract = {

Background:\ Black tea (Camellia sinensis) has been used as a daily beverage for time immemorial. Immunomodulatory effects of tea are recognized as it stimulates the proliferation of cultured human peripheral blood mononuclear cells. Anti-inflammatory effects of tea have also been depicted in the available literature. Therefore, we designed this study to examine the potential immunemodulatory and anti-inflammatory activities of black tea in a rat model and in human peripheral mononuclear cells.\ Aims:\ The purpose of the study was to determine (1) evaluation of anti-inflammatory effects of black tea on rats, (2) evaluation of immunemodulator effects of black tea on rats, and (3) evaluation of immunemodulator effects of black tea on human peripheral mononuclear cells.\ Materials and Methods:\ Black tea decoction (10\% and 20\%) was prepared. Acute anti-inflammatory activity of tea decoction was evaluated using carrageenan and dextran whereas chronic anti-inflammatory (Immunomodulatory) effects were evaluated in a complete Freunds{\textquoteright} adjuvant-induced arthritis model. Immunostimulatory role was evaluated in cultured human (in vitro) peripheral mononuclear cells (T-lymphocytes) by using methyl thioazolyl tetrazolium (MTT) and Trypan blue assay.\ Study Design:\ An experimental study was designed.\ Results:\ Black tea decoction (10\% and 20\%) strength has shown significant anti-inflammatory effects (64.8\% and 77\% reduction, respectively), on carrageenan-induced acute inflammatory models (rat paw edema) which can be comparable with the standard drug indomethacin (89.1\%). In a chronic anti-inflammatory model, black tea decoction (10\% and 20\%) has shown significant suppressive effects on rat paw edema (38.56\% and 69.53\%) observed on 21\ st\ day. Lymphoproliferative action of tea was evaluated on human peripheral mononuclear cells using an MTT assay where the number of living cells were expressed in terms of optical density at 570 nm. An experiment has shown that black tea increases the maximum number of T-lymphocytes at 72 h with a maximum strength of 20\%. Maximum number of viable cells (T-lymphocytes) was observed with black tea at 20\% strength at 72 h. The results were expressed as mean {\textpm} SD, and the significance was evaluated by Student{\textquoteright}s\ t-test\ versus\ control, with\ P\ \< 0.05 implying significance.\ Conclusions:\ Taken together, our data indicate that black tea has potential anti-inflammatory and immunomodulatory action and this corroborates with the current trend of tea being promoted as a {\textquoteright}health drink{\textquoteright}.

}, keywords = {Anti-inflammatory, Black tea, Immunomodulation}, doi = {10.4103/0974-8490.91029}, author = {Chandan Chattopadhyay and Nandini Chakrabarti and Mitali Chatterjee and Sonali Mukherjee and Kajari Sarkar and A Roy Chaudhuri} } @article {588, title = {Diuretic activity of Sri Lankan black tea (Camellia sinensis L.) in rats}, journal = {Pharmacognosy Research}, volume = {1}, year = {2009}, month = {January 2010 }, pages = {4-10}, type = {Original Article}, chapter = {4}, abstract = {

The aim of this study was to evaluate the diuretic potential of Sri Lankan black tea (Camellia sinensis L.). This was assessed in rats using high grown Dust grade No: 1 tea, which is consumed widely by the tea drinkers worldwide. Different doses of hot black tea brew (BTB) (84, 167, 501 or 1336 mg/ml respectively equivalent to 1.5, 3, 9 and 24 cups) were made and orally administered to previously starved (24 h) but subsequently hydrated (with 15 ml of isotonic saline) rats and their urinary output was monitored cumulatively at hourly intervals for 6h. The reference drug used was frusemide (13 mg/kg). The results showed that BTB induced significant (P \< 0.05), mild to moderate and dose- dependent diuresis (starting from 167 mg/ml). This diuretic activity had a fairly rapid onset (within 2 h) and relatively short duration of action (3 h). BTB also significantly (P \< 0.05) increased the overall urinary frequency. Further, the diuretic activity of BTB was less potent to frusemide (by 45\%). Decaffeination of black tea almost completely abolished the diuresis. The diuresis of the BTB was solely due to increased (by 55 \%) urinary Na+ excretion (with no urinary K+ loss). Further, the chronic daily administration of the BTB did not develop tolerance or induce toxicity (general, renal and hepatic). It is concluded that BTB made from Sri Lankan high grown Dust grade No :1 tea has safe, mild to moderate diuretic activity with rapid onset and relatively short duration of action. Further, this study supports the claim made by Sri Lankan indigenous physicians that it is a diuretic.

}, keywords = {Black tea, Camellia Sinensis, Diuresis, Dust grade tea, Sri Lankan tea}, author = {W.D. Ratnasooriya and T.S.P. Fernando and R.A.A.R Ranatunga} } @article {854, title = {Studies on the Effect of Processing Methods on the Antihyperglycemic activity of Herbal Teas from Leaves of Vernonia amygdalina Del}, journal = {Pharmacognosy Research}, volume = {1}, year = {2009}, month = {January 2010 }, pages = {256-260}, type = {Original Article}, chapter = {256}, abstract = {

The leaves of Vernonia amygdalina Del (Asteraceae) was processed into herbal tea using the black and green tea processing techniques. The green tea obtained was used as such while a portion of the black tea was flavored with O. basilicum or O. gratissimum. Methanol extracts of the flavored and unflavored herbal teas, obtained by cold maceration, were subjected to pharmacological studies for antihyperglycemic activity in alloxan diabetic rats and pytochemical analysis. Results showed that single oral administration of the tea extracts reduced blood glucose level of diabetic rats to varying the extents. Extract of green tea (GTE) caused a moderate reduction in blood glucose levels while black tea (BTE) evoked a mild dose-related effect. Extracts of the flavored tea caused significant (P\<0.05) reductions in blood glucose levels. While the effect of extract of O. basilicum flavored tea (BTOBE) was dose-related, that of O. gratissimum flavored tea (BTOGE) was non-dose-related. A comparison of the magnitude of reduction in blood glucose level showed the order of potency: BTOBE\>BTOGE\>GTE\>BTE. Phytochemical analysis showed relative presence of alkaloids, saponins, tannins, flavonoids, steroids and terpenoids with GTE having the highest concentration of these constituents. These findings suggest that black tea technique may be preferred for processing leaves of V. amygdalina into herbal tea since it preserved the antihyperglycemic activity. Green tea method may reduce the antihyperglycemic effect even though it preserves the phytochemical constituents better than black tea technique. Flavoring of black tea with Ocimum spp enhances the antihyperglycemic effect due to their inherent hypoglycemic activity.

}, keywords = {Antihyperglycemic, Black tea, Green tea, Herbal tea, Ocimum spp, Vernonia amygdalina}, doi = {Nil}, author = {Okafor G.I and Okoli C.O and Odo A.S and Kelechi N.R} }