Vol. 7(20), pp. 1351-1361, 25 May, 2013 DOI: 10.5897/JMPR12.050 Journal of Medicinal Plants Research ISSN 1996-0875 © 2013 Academic Journals http://www.academicjournals.org/JMPR Review Terminalia chebula - A pharmacognistic account Harpreet Walia* and Saroj Arora Department of Botanical and Environmental Sciences, Guru Nanak Dev University, Amritsar-143005, Punjab, India. Accepted 28 May, 2012 Herbal medicines are in great demand in the developed as well as developing countries for primary heath care because of their wide biological and medicinal activities, higher safety margin and lower costs. Terminalia chebula Retz. is an important medicinal plant and has been extensively used in ayurveda, unani and homoeopathic medicine and has become cynosure of modern medicine. It is called “King of Medicines” in Tibet and is always listed first in ayurvedic meteria medica because of its extraordinary power of healing. It has been reported to exhibit a variety of biological activities including, antidiabetic, antimutagenic, antibacterial, antifungal and antiviral activities. All these activities are due to presence of various phytochemicals in plants. Thus, phytochemical analysis of plant is necessary and provides useful information. This review gives a bird’s eye view, mainly on the biological and pharmacological activities of some compounds of T. chebula , clinical studies and plausible medicinal applications, along with their safety evaluation. Key words: Terminalia chebula Retz., biological and pharmacological activities, plausible medicinal applications, safety evaluation. INTRODUCTION Excessive free radical production due to environmental al., 2003). The history of the use of medicinal plants for pollution, harmful ultraviolet (UV) radiation and toxic alleviation of diseases has its origin in primitive times. chemicals poses a tremendous threat to our body cells Though natural product chemistry is an age old science causing disease states such as cancer, atherosclerosis, yet it is brimming with fresh potential in the current arthritis, diabetes, dermatological system disorders, century with many reports on plants. Several plants are cataract and other age related diseases of man (Valko et being used in ayurvedic medicines and their medicinal al., 2007). Some of reactive oxygen species which cause values have been documented in ancient Indian dreadful diseases in human body are hydroxyl radical literature. One of the important plants among these in . - ( OH), superoxide anion (O2· ), hydrogen peroxide (H 2O2), ayurveda is Terminalia chebula which is known to be rich 1 singlet oxygen ( O2) etc. To protect the cells and organ in tannins, vitamin C, gallic acid, ellagic acid, systems of the body against these reactive oxygen anthraquinones, triterpenoids and other miscellaneous species, a highly sophisticated and complex antioxidant compounds (Juang et al., 2004). The various extracts of protection system are present. It involves a variety of T. chebula has been reported to show a broad spectrum components, both endogenous and exogenous in origin, antibacterial, antifungal, antimutagenic, antiviral and that function interactively and synergistically to neutralize antioxidant activities (Inamdar and Rajarama, 1954; free radicals. Plants are the potent source of many Trease and Evans, 1983; Kurokawa et al ., 1995; El- bioactive compounds such as phenolics, flavonoides, Mekkawy et al ., 1995; Dutta et al ., 1998; Kaur et al., which have free radical scavenging properties and 1998; Jagtap and Karkera, 1999; Malckzadeh et al., promoted as ‘Magic Bullets’ for optimum health (Cai et 2001; Suguna et al., 2002; Sandip, 2003; Vonshak et al., *Corresponding author. E-mail: [email protected]. 1352 J. Med. Plants Res. 2003; Walia et al., 2011). According to Indian mythology, 2006). The flowers are monoecious, dull white to yellow, this plant originates from the drops of ambrosia (Amrita), with a strong unpleasant odour, borne in terminal spikes which fell on the earth when Indra was drinking it. The or short panicles. The fruits are drupe-like, 2 to 4.5 cm fruits are the most important part used in the ayurvedic long and 1.2 to 2.5 cm broad, blackish, with five formulation. The fruits come in the class of Myrobalan, longitudinal ridges, glabrous, ellipsoid to ovoid and yellow which is a symbol of “Creative power of thought” and are to orange brown in colour (Aneja and Joshi, 2009). It is elixir of long life which in high levels of meditative praxis capable of growing in different range of soils. The plant can materialize the unseen worlds in the manner of the flourishes well in areas with an annual rainfall between myrobalan berry concretised upon the palm of the hand. 100 to 150 cm and a temperature range from 0 to 17°C. Thus, this sublime fruit is not just a medicine, but in its materialization by the will of the Buddha upon his hand, it represents blessings from unseen realms, like the healing Medicinal value energy radiating upon devotees in their worship. In this review, an attempt has been made to review briefly the The plant is described as an astringent, digestive, different compounds present in this plant which are antiseptic, alternative, laxative, diuretic and carminative responsible for its bioactivities. (Hartwell, 1982; Singh, 1990; Barthakur and Arnold, 1991). It is also used for blood purification, heal wound and peptic ulcers, diabetes, chronic fever, hypertensions, Natural distribution heart problem, jaundice, vesical and renal calculi, epilepsy, leprosy, ascites, diarrhoea, vomiting, dysentery, T. chebula occurs naturally from the sub-Himalayan cough and dyspnoea. It is also a part of wonder drug region of Nepal and Northern India to Sri Lanka, “Triphla” which is composite mixture of T. chebula , Myanmar, Thailand, Indo-China and Southern China Terminalia bellerica and Emblica officinalis , a traditional (Saleem et al., 2001; Kusirisin et al., 2009; Li et al., 2011) medicine used for the treatment of many chronic In India, this tree is found in sub-Himalayan tracks form diseases such as aging, heart ailments and hepatic Ravi eastwards to West Bengal, Assam, ascending up to diseases (Burapadaja and Bunchoo, 1995; Jagetia et al., an altitude of 1500 m in the Himalayas. This tree is wild in 2004; Srikumar et al., 2005). The various extracts of T. the forests of Northern India, Uttar Pradesh, Bengal, chebula has been reported to show a broad spectrum Madras, Tamil Nadu, Karnataka, Mysore and Southern antibacterial, antifungal, antimutagenic and antiviral Maharastra. activities (Inamdar and Rajarama, 1954; Trease and Evans, 1983; Kurokawa et al., 1995; El-Mekkawy et al., 1995; Dutta et al., 1998; Kaur et al., 1998; Jagtap and Taxonomy and nomenclature Karkera, 1999; Malckzadeh et al., 2001; Suguna et al., 2002; Sandip, 2003; Vonshak et al., 2003; Bonjar, 2004). Kingdom: Plantae Subkingdom: Tracheobionta Superdivision: Spermatophyta CHEMICAL CONSTITUENTS Division: Magnoliophyta Class: Magnoliopsida T. chebula is known to be rich in tannins, gallic acid, Order: Myrtales ellagic acid, anthraquinones, triterpenoids and other Family: Combretaceae miscellaneous compounds. Genus: Terminalia Species: Terminalia chebula Tannins Morphological description Tannins are among the array of chemical compounds that are widely distributed in the plant kingdom and T. chebula is a flowering, evergreen, heart gladdening belong to the phenolic class of secondary metabolites. and strength-bestowing tree which attain a height of 30 Tannins are oligomeric compounds having multiple m, with a trunk up to 1 m diameter and widely spreading structural units with free phenolic groups having branches and a brown roundish crown. Its fragrance molecular weight ranging from 500 to 3000 daltons. spreads to infinite distances and its brightness illumines Amongst the few families of dicotyledons, particularly the earth and sky. The leaves are alternate to sub- Combretaceae is a rich source of tannins. T. chebula opposite in arrangement, oval, 7 to 18 cm long and 4.5 to belongs to the family Combretaceae and is an important 10 cm broad with a 1 to 3 cm petiole, elliptical, oblong, medicinal tree, which contains hydrolysable tannins (Han with an acute tip, cordate at the base, margins entire, et al., 2006; Kaur et al., 1998). Maximum amount of it is glabrous above with a yellowish pubescence below (Deb, present in the fruit pulp and dried pericarp of the seed Walia and Arora 1353 TANNINS Non-hydrolysable Hydrolysable Gallotannins Ellagitannins Complex tannins Condensed tannins Figure 1. Classification of tannins. Figure 2. A hydrolysable tannin with a glucose core. that contains 30 to 35% of tannins (Chadha, 1989; Khare, semialata, Quercus infectoria , seed pods of Caesalpinia 2004). Tannins are classified into two broad group viz. spinosa and fruits of T. chebula. As their name infers, hydrolysable and condensed tannins (Haslam, 1996). hydrolyzable tannins are readily degraded into smaller The observation that many tannins can be fractionated molecules. The hydrolysable tannins are subdivided into hydrolytically into their components, by treatment with hot the gallotannins and ellagitannins. water or with tannases, led to the classification of such tannins as “hydrolysable tannins”. Non-hydrolysable Gallotannins: Gallotannins are all those tannins in which oligomeric and polymeric proanthocyanidins were galloyl units or their meta -depsidic derivatives are bound classified as condensed and complex tannins. The main to diverse polyol, catechin or triterpenoid