~ 253 ~ Journal of Pharmacognosy and Phytochemistry 2016; 5(1): 253-255 E-ISSN: 2278-4136 P-ISSN: 2349-8234 JPP 2016; 5(1): 253-255 Received: 08-11-2015 Accepted: 11-12-2015 Srikala Ganapathy Research Scholar, Research and Development Centre, Bharathiar University, Coimbatore, Tamil Nadu, India. Karpagam S Associate Professor, Department of Botany, Queen Mary’s College, Chennai, Tamil Nadu, India. Correspondence Srikala Ganapathy Research Scholar, Research and Development Centre, Bharathiar University, Coimbatore, Tamil Nadu, India. In vitro antibacterial and phytochemical potential of Aegle marmelos against multiple drug resistant (MDR) Escherichia coli Srikala Ganapathy, Karpagam S Abstract Alarming increase of antibiotic resistant bacteria in recent years result in limited options for treatment of bacterial diseases. Escherichia coli is one of the most common Gram negative bacterial pathogen causing community and hospital acquired infections. Since the emergence of antibiotic resistant strains of Escherichia coli is at higher pace, there is an urgent need for new antibacterial compounds. Medicinal plants are alternative rich source of useful antibacterial agents. The present study assessed the photochemical and in vitro antibacterial activity of ethanol, chloroform, hexane and water extracts of leaves and fruits of Aegle marmelos against MDR Escherichia coli. Zone of inhibition diameters were measured. The antibacterial activity was absent in hexane and water extracts. Chloroform extracts showed moderately good activity. However, highest antibacterial activity was found in ethanol extracts. The antibacterial compounds found in leaf and fruit extracts were tannins, flavonoids, saponins and alkaloids. Keywords: Aegle marmelos extracts, multiple drug resistant (MDR) Escherichia coli, antibacterial activity. 1. Introduction The emergence of antibiotic resistance is a global health concern. Gram negative bacterial resistance is of particular importance as there is dearth of novel antibiotics directed against these microorganisms [1] . The increase in antibiotic resistance is due to several factors but the major cause appears to be excessive use of antibiotics [2] . Increase in the incidence of multidrug resistant Escherichia coli has been reported in various studies [3] . Escherichia coli is the most common Gram negative bacterial pathogen causing community and hospital acquired urinary tract infections [4] . Enteric and diarrhoeal infections are major public health problems in developing countries and contribute to death of 3.3 to 6 million children annually. Enteric bacteria that includes Escherichia coli along with other bacterial pathogens are the major etiological agents of sporadic and epidemic diarrhea in both children and adults [5, 6] . An isolate is considered as multiple drug resistant if found to be resistant to three or more antimicrobials belonging to different classes or groups of antimicrobials. As multi drug resistant Escherichia coli are widely distributed in hospitals and increasingly being isolated in community, there is an urgent need to search for new antimicrobial agents [7, 8] . Aegle marmelos belongs to family Rutaceae, commonly known as Bael tree [9] , is one of the most important tree species indigenous to India, China, Burma and Srilanka [10] and has been used by the inhabitants of Indian subcontinent for over 5000 years. It’s a slow growing, medium sized tree, upto 12- 14 m tall with short trunk, thick bark, alternate leaves, borne singly or in group, composed of 3 to 5 oval, pointed leaflets [11] . Leaves, fruits, stem and roots of the tree have been used in ethno medicines for several medicinal properties like astringent, antidiarrhoeal, antidysentric, demulcent, antipyretic, aphrodisiac and an antidote to snake venom [12] . Unripe fruit extract of Aegle marmelos has shown gastro protective and antidiarrhoeal properties [13] . The leaves are having astringent, laxative and expectorant effects and are also in the treatment of ophthalmia, deafness, inflammations, diabetes, diarrhea, dysentery and asthma [14] . Aegle marmelos has diverse pharmacological profile due to the presence of wide spectrum range of chemical entity [15] . Based on the background knowledge of therapeutic potential of the plant species and limited Based on the background knowledge of therapeutic potential of the plant species and limited work on the antibacterial activity specifically against multiple drug resistant (MDR)