~ 181 ~ Journal of Medicinal Plants Studies 2018; 6(1): 181-184 ISSN (E): 2320-3862 ISSN (P): 2394-0530 NAAS Rating: 3.53 JMPS 2018; 6(1): 181-184 © 2018 JMPS Received: 28-11-2017 Accepted: 29-12-2017 Ramalashmi K Department of Biotechnology & Research, SNMV College of Arts a& Science, Coimbatore, Tamil Nadu, India Prasanna Vengatesh K Department of Biotechnology & Research, SNMV College of Arts a& Science, Coimbatore, Tamil Nadu, India Magesh K Department of Biotechnology & Research, SNMV College of arts a& Science, Coimbatore, Tamil Nadu, India Sanjana R Department of Biotechnology & Research, SNMV College of Arts a& Science, Coimbatore, Tamil Nadu, India Siril Joe S Department of Biotechnology & Research, SNMV College of arts a& Science, Coimbatore, Tamil Nadu, India Ravibalan K Department of Biotechnology & Research, SNMV College of Arts a& Science, Coimbatore, Tamil Nadu, India Correspondence Ramalashmi K Department of Biotechnology & Research, SNMV College of Arts a& Science, Coimbatore, Tamil Nadu, India A potential surface sterilization technique and culture media for the isolation of endophytic bacteria from Acalypha indica and its antibacterial activity Ramalashmi K, Prasanna Vengatesh K, Magesh K, Sanjana R, Siril Joe S and Ravibalan K Abstract The objective of the current study was to optimize the isolation procedure of the endophytic bacteria from medicinal plant. Medicinal plants are the potential hosts of endophytic microorganisms like bacteria, fungi, actinomycetes etc. Endophytic bacteria live symbiotically within the plant and in turn helping the plant in number of ways like growth, protection to environmental conditions, and sustainability, in favour of the hosts. They produce a wide range of bioactive compounds that are economical importance to humans. The present investigations were undertaken to optimize the isolation and identification of bacterial endophytes in leaf tissue of Acalypha indica plant growing at Coimbatore, India. Studies on the optimization of growth of the isolates were performed by varying growth medium. The ability of bacterial isolates were tested for abtimicrobial activity assay. Future studies will determine the potential medium to isolate endophytic bacteria that can be further applied for various applications like biological control, growth promotion and enzyme production. Keywords: Endophytic bacteria, Acalypha indica, bioactive compound, optimization Introduction Bacterial endophytes are a class of endosymbiotic microorganisms including bacteria, fungi, and actinomycetes widespread among intra- and intercellular plant tissues for all or part of their life cycle do not cause plant disease or any morphological changes. Endophytes have the ability to colonize internal plant tissues of healthy leaves, petioles, stems, twigs, bark, root, fruit, flower, and seeds without causing any apparent harm or pathogenic infection to their host plants. Endophytic bacteria have been shown to have several beneficial effects on their host plant, including growth promoting activity, modulation of plant metabolism and phytohormone signalling that leads to adaptation to environmental abiotic or biotic stress. Use of endophytic bacteria presents a special interest for development of agricultural applications that ensure improved crop performance under cold, draught or contaminated soil stress conditions or enhanced disease resistance (Inga Miliute et al., 2015) [7] . Recenty Jha et al., 2013 [8] reported that endophytic microorganisms resides inside the plant to for improve plant performance in integration with plant disease management systems. Many bioactive metabolites are originated from microbial organisms, bacteria are the heart important groups of eukaryotic organisms that have wide capacity to produce numerous metabolites with antimicrobial activities and possess potential application as drugs. Recent studies have reported hundreds of natural products including substance of alkaloids, terpenoids, flavonoids, steroids etc. Metabolites of endophytes have been reported to inhibit a number of microorganisms (Fisher et al., 1984; Gurney & Mantle, 1993) [3, 5] . It is estimated that there might be as many as one million different endophyte species, however, only a handful of them have been described (Petrini; 1991) [11] , which means investigating the metabolites of endophytes can increase the chance of finding novel antimicrobial natural products. There are numerous new endophytic species may exist in medicinal plants, it follows that endophytic microorganisms are important components of microbial biodiversity (Zhang et al., 2009) [14] . Acalypha indica Linn, commonly known as Indian copper leaf is a medicinal plant from the tropical Africa and the Indian Ocean islands is widely used in traditional medicine to treat skin