10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 1 2013 (January - March) Endophytic fungi found inside the plant tissue are endosymbionts, protecting their host from pests, pathogens, etc. Twenty eight endophytic fungi were isolated from different parts of lessThan i greaterThan Nerium oleander lessThan /i greaterThan L lessThan i greaterThan ., lessThan /i greaterThan out of which, 54% of isolates were from flower, 39% from stem and 7% from leaf parts. Thirty six percent of the isolates showed antimicrobial activity against tested pathogens. The potential isolates such as lessThan i greaterThan Fusarium semitectum lessThan /i greaterThan (Nof-3) lessThan i greaterThan , lessThan /i greaterThan lessThan i greaterThan Colletotrichum gloeosporioides lessThan /i greaterThan (Nof-7) lessThan i greaterThan , Alternaria alternata lessThan /i greaterThan (Nof-8) and Mycelia Sterilia sp.1 (Nos-6) were subjected to the production and extraction of secondary metabolites. All the four fungal extracts inhibited lessThan i greaterThan Staphylococcus aureus lessThan /i greaterThan and lessThan i greaterThan Bacillus cereus lessThan /i greaterThan at 20 μg/mL (MIC). Extracts of lessThan i greaterThan C lessThan /i greaterThan . lessThan i greaterThan gloeosporioides lessThan /i greaterThan and Mycelia Sterilia sp.1 showed activity against lessThan i greaterThan Pseudomonas aeruginosa lessThan /i greaterThan at MIC of 20 μg/mL. The growth of lessThan i greaterThan Escherichia coli lessThan /i greaterThan was suppressed by all the tested extracts at MIC of 20 μg/mL except lessThan i greaterThan F lessThan /i greaterThan . lessThan i greaterThan semitectum lessThan /i greaterThan . lessThan i greaterThan A lessThan /i greaterThan . lessThan i greaterThan alternata lessThan /i greaterThan & Mycelia Sterilia sp.1 extracts were active against lessThan i greaterThan Salmonella typhimurium lessThan /i greaterThan at 20 μg/mL. The growth of lessThan i greaterThan Candida albicans lessThan /i greaterThan was inhibited by Mycelia Sterilia sp.1 at 20 μg/mL lessThan i greaterThan . lessThan /i greaterThan The zones of inhibition were statistically significant with respective positive controls. RAMESHA. A, SUNITHA.V. H, AND C. SRINIVAS Nerium oleander L.,Endophytic fungi, Antimicrobial activity, Secondary metabolites, Minimum inhibitory concentration. 683-693