farther study in green and black tea should be done particularly antimicrobial study.
References
(1) Berube P.S., Pelletier C. and Dore J. (2005). Effects of encapsulated green tea and Guarana extract containing a mixture of epigallocateechin – 3- gallate and caffeine on 24 hours energy expenditure and fat oxidation in men. Br.J.Nutr. 94(3):432 -436.
(2) Chiu, A, E, Chan M.C.and Kern D.G. (2005). Double –blinded, placebo- controlled trial of green tea extracts in the clinical and histological appearance of photo aging skin.Dermatol Slurg. 31(7 pt 2):855 – 860.
(3) Chow H.H., Hakim, I.A., Vining D.R. (2005).Effects of dosing condition on the oral bioavailability of green tea catechins after single=dose administration of polyphenols in healthy individuals. Clin. Cancer Res. 11(12):4627-4633.
(4) Laurie S.A., Miller V.A., (2005). Study of green tea extract in patients with advanced lung cancer. Cancer Chemother Pharmacol. 55(1):33 -38.
(5) Fukino Y., Shimbo M. and Aoki N. (2005). Randomized controlled trial for an effect of green tea consumption on insulin resistance and inflammation markers.J.Nutr.Situation I (Tokyo) 51(5):335 -342.
(6) Riemersma R.A., Rice C.A., Tyrell R.M., Clifford M.C.and Lean M.E.(2001).Tea flavonoids and Cardiovascular Health. QJM.94 (5):277 -282.
(7) Maron D.J., Lu G.P and Cai N.S (2003). Cholesterol – lowering effect of the aflavins- Enriched tea extract: a randomized controlled trial. Med, fl1/4 44 MJ.163 (12):1448 – 1453.
(8) AOAC. 1990. Association of Official Analytical Chemists. Official Methods of Analysis. 15th edition. Washington.
(9) Goldstein, J.L and T. Swain 1963. Change in tannin in ripening fruit. Phyto chemistry (2),371
(10) FAO (1991). Guide to Specification: general notices, general analytical techniques, identification tests, test solution and other reference materials. FAO Food and Nutrition paper 5 Rev.2 Rome.
(10) Price M.L. and Butler L.G. (1987).A critical evaluation of the Vanillin
Reactions as an assay for tannin in sorghum rain. J. Agric. Food chem. 26
(5): 1214-1218.
(12) Balbaa S.I., Hilal S.H. and Zaki A.Y. (1981). Medicinal Plant Constituents. 3rd
Ed., General Organization for University and Schoolbooks. Cairo.
Table (1): Chemical constituents that available (+ ve) and non-available (- ve) in green and black tea.
Solvent extraction /
Compounds
Water extraction
Ethanol extraction
Petroleum ether extraction
Green tea
Black tea
Green tea
Black tea
Green tea
Black tea
1/Alkaloid
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
2/Anthraquinones
(-) ve
(-) ve
(-) ve
(-) ve
(-) ve
(-) ve
3/Cardenolides
(-) ve
(-) ve
(+) ve
(+) ve
(+) ve
(+) ve
4/Tannin
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
5/Saponins
(+) ve
(+) ve
(-) ve
(-) ve
(-) ve
(-) ve
6/Coumarin
(-) ve
(-) ve
(-) ve
(-) ve
(-) ve
(-) ve
7/Flavonoids
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
8/Steroid
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
9/Carbohydrates
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
(+) ve
Table (2): Alkaloid and tannin content in extracted – tea solvent (water, ethanol and petroleum ether of green and black type.
Type of solvent
Water extraction
Ethanol extraction
Petroleum ether extraction
Type of tea
Green tea
Black tea
Green tea
Black tea
Green tea
Black tea
Alkaloid Mg/g
5.4a±1
6.4 a ±0.5
4.3 a ±0.3
4.5 a ±1.2
4.6 a ±1
5.2 a ±1.4
Tannin %
1.2 a ±0.5
1.2 a ±1
1.8 a ±2
0.5 b ±0.01
1.5 a ±1
1.0 a ±0.8
* Each value is average of three replicates expressed on dry weight basis.
Murwan K. Sabah ELKheir 1
1. Department of Biochemistry, School of Biotechnology, Faculty of Science and Technology, El Neelain University, P.O.Box 12702, Khartoum, Sudan
Email address; murwansabahelkhier@yahoo.com
Article from articlesbase.com
Find More Black Tea Articles
