Advances in Biological Research 3 (1-2): 53-56, 2009 ISSN 1992-0067 © IDOSI Publications, 2009 Corresponding Author: M. Rahman, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi-6205, Bangladesh 53 The Determination of Antibacterial and Antifungal Activities of Polygonum hydropiper (L.) Root Extract M. F. Hasan, R. Das, Alam Khan, M.S. Hossain and M. Rahman 1 2 1 1 Department of Genetic Engineering and Biotechnology, 1 Department of Pharmacy, University of Rajshahi, Rajshahi-6205, Bangladesh 2 Abstract: A study was conducted to determine the antibacterial and antifungal activities of Polygonum hydropiper (L.) root extract on chloroform against both bacteria and fungi using the disc diffusion method. The extract showed significant antibacterial activities against four gram-positive (Bacillus subtilis, Bacillus megaterium, Stapphylococcus aureus and Enterobacter aerogenes) and four gram-negative (Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi and Shigella sonnei) bacteria. The minimum inhibitory concentration (MIC) values against these bacteria ranged from 16 to 64 µg/ml. The antifungal activities were found strong against six fungi (Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus, Candida albicans, Rizopus oryzae and Tricophyton rubrum). It can be used in the folk medicine at different parts of the world to treat many diseases including bacterial and fungal infections. Key words: Polygonum hydropiper Chloroform extract of roots Antibacterial activity MIC Antifungal activity INTRODUCTION mortality in immunocompromised patients in developing Polygonum hydropiper L. is an important been done which aim at knowing the different medicinal plant belongs to the family of Polygonaceae. antimicrobial and phytochemical constituents of medicinal The whole plant has been found to contain flavones and plants and using them for the treatment of microbial flavonoid glycosides, such as quercetin galactosides, infections as possible alternatives to chemically synthetic a sesquiterpene acid, viscosumic acid, oxymethyl- drugs [7]. There are many reports on antimicrobial anthraquinones and polygonic acid [1]. The plant also activities of several medicinal plant species including, has some insecticidal properties [2, 3]. The plant also Polygonum multiflorum [8], Polygonum tinctorium [9] possesses bitter, stimulant, tonic, diuretic, carminative, and Amorphophallus campanulatus [10]. But there are no anthelmintic, emmeragogue, haemostatic and lithotripter reports on antimicrobial activities on this valuable plant. properties [4]. The whole plant, either on its own or mixed Hence, the present study was undertaken to determine the with other herbs, is decocted and used in the treatment of antibacterial and antifungal activities of chloroform extract a wide range of ailments including diarrhoea, dyspepsia, of Polygonum hydropiper roots. itching skin, excessive menstrual bleeding and hemorrhoids [5]. This species is of economic interest of its MATERIALS AND METHODS wide ranging pharmacological activity and one of the major constraints in utilizing natural populations is the Plant Materials Collection: The roots of Polygonum existence of plant to plant chemovariability. That is why, hydropiper were collected during January, 2007 from the there is an increasing awareness in people for the use of Rajshahi University Campus, Rajshahi, Bangladesh and this herbal medicinal plant day by day. were identified by Md. Shahed Alam, Senior technical The frequency of life-threatening infections caused officer, Herbarium Museum, Department of Botany, by pathogenic microorganisms has increased worldwide University of Rajshahi, Bangladesh, where its voucher and is becoming an important cause of morbidity and specimen (No. 10203) was deposited, for reference. countries [6]. To overcome this problem many works have