The Comparative Qualitative and Quantative Analysis on Green and Black Tea (Camellia sinensis) Extracted by Three Solvents Studied in Sudan
By
Murwan K. Sabah EL-Kheir 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
Abstract: The aim of this study is to investigate the phytochemicals screen of Green and Black Tea extracted by water, ethanol and petroleum ether. The results revealed that the presence of alkaloid, tannin, steroid, flavonoid and carbohydrate in Green and Black Tea extracted water ethanol and petroleum ether. In addition, Green and Black Tea extracted by water contained saponins, but Green and Black Tea extracted by ethanol and petroleum ether do not contained saponins.Green and Black Tea extracted by ethanol and petroleum ether contained cardenolide, but Green and Black Tea extracted by water do not contained cardenolide and finally Green and Black Tea extracted by water ethanol and petroleum ether do not contain anthraquiaone and coumarin. The alkaloid content of Green Tea extracted by water, ethanol and petroleum ether is 5.4, 4.3 and 4.6 Mg/g, respectively. While alkaloid content of Black Tea extracted by water, ethanol and petroleum ether is 5.4, 4.3, and 4.Mg/g, respectively. The tannin contents of Green Tea extracted by water, ethanol and petroleum ether are 1.2, 1.8 and 1.5 %, respectively. While tannin contents of Black Tea extracted by water, ethanol and petroleum ether are 1.2, 0.5, 1 %, respectively.
Keywords: Tea, Alkaloid, Tannin and Qualitative.
1.0 Introduction
Green and Black Tea is made up from Camellia sinensis, which is characterized as a perennial evergreen shrub. Tea varieties reflected the growing region (Ceylon and Assam), districted (Darjeeling), form (pekoe and gunpowder) and processing method (green, black and oolong). India and Srilanka is major producers of green tea. The Turkish trader’s reportedly introduced to Western culture in 6th Century (1) .It has many uses for its mild stimulant and medicinal properties (prevent cancer (2), prostate cancer (3), asthma (4), dental cavity, diabetes (5), heart attack (6), high cholesterol (7), improve fertility (3), memory enhancement, mental performance and menopausal symptoms). The green tea is prepared by exposing the gathered leaves to air until superfluous moisture is eliminated, leaves roasted over a brick wood fire and continually stirred until leaves become moist and flaccid, after which leaves pass to rolling table and rolled into balls and subjected to pressure which twist them and gets rid of the moisture, then leaves shaking out on flat trays, again leaves roasted over a slow and steady charcoal fire and kept leaves in rapid motion for an hour to hour and half., till leaves assume a dullish green colour after that the leaves winnowed, screened, and graded into different types. While black tea, gathered leaves are exposed to air for long period, gathered up, tossed until soft and flaccid, further exposure, roasted in an iron pan for about five minutes and after rolling and pressing the leaves are shaken out, exposed to the outer air for some hours, re-roasted for three or four minutes and recoiled, spread out in baskets and exposed to heat of charcoal fire for five or six minutes and then rolled for third time and again heat and finally dried in baskets over charcoal fire from which leaves become black in colour. Steroid compounds are containing the perhydrocyclopentano-phenanthrene skeleton and usually occur in glycosidal combination with sugar (8). Alkaloids are group of natural products (atropine, quinine, morphine …etc) which are widely used to treat Malaria and Cancer diseases (8). Cardenolides are act on the heart direct or indirect mechanism to enhance the force and velocity of the contraction, therefore it is known as cardiotonic (8). Carbohydrates are the most abundant organic constituents of plant, serve as the major source of chemical energy (sugar and starch), as well as important constituents of supporting tissue (cellulose in wood, cotton and flax) (8). Anthraquinones are oxygenated derivative of pharmacological importance that is used as laxatives or cathartics, anti-inflammatory, antibacterial, antifungal and also as natural dyes (8). The flavonoid, constitute one of most diverse and widespread group of natural products, found in fruit, vegetables, nuts, seeds, stem, flowers, as well as tea, and are one of the most important constituents of the human diet(8). Coumarins are derivative of benz-? pyrone, or lactones of o-hydroxcinnamic acid such as coumarin, umbelliferonee, aesculetin, daphnetin, fraxetin and scopoletin, they are
