_____________________________________________________________________________________________________ *Corresponding author: E-mail: ayantola86@gmail.com; Journal of Advances in Microbiology 9(4): 1-10, 2018; Article no.JAMB.40580 ISSN: 2456-7116 Antibacterial and Ftir Spectral Analysis of Methanolic Extract of Gliricidia sepium Leaves M. K. Oladunmoye 1 , K. J. Ayantola 2* , A. A. Agboola 3 , B. M. Olowe 2 and O. G. Adefemi 1 1 Department of Microbiology, Federal University of Technology, Akure, Ondo State, Nigeria. 2 Department of Science Laboratory Technology, Ekiti State University, Ado Ekiti, Nigeria. 3 Department of Medical Microbiology and Parasitology, Afe Babalola University, Ado Ekiti, Ekiti State, Nigeria. Authors’ contributions This work was carried out in collaboration between all authors. Authors KJA and MKO designed the study, wrote the protocol, and wrote the first draft of the manuscript. Author MKO read first manuscript. Authors OGA and KJA performed the statistical analysis, managed the interpretation of data of the study. Author KJA managed the literature searches. Authors KJA, AAA and BMO read and approved the final manuscript. Article Information DOI: 10.9734/JAMB/2018/40580 Editor(s): (1) Pongsak Rattanachaikunsopon, Professor, Department of Biological Science, Faculty of Science, Ubon Ratchathani University, Thailand. Reviewers: (1) Anuge Benedicta Olohigbe, University of Benin, Nigeria. (2) Ioana Stanciu, University of Bucharest, Romania. Complete Peer review History: http://www.sciencedomain.org/review-history/24035 Received 19 th January 2018 Accepted 25 th March 2018 Published 7 th April 2018 ABSTRACT Aim: The present study was carried out with the objective to analyse the methanol extracts of Gliricidia sepium leaves using Fourier transform infrared (FTIR) spectroscopic method. Place and Period of Study: The study was carried out at the Department of Microbiology Federal University of Technology Akure between January 2013 and July 2014. Methodology: The in vitro killing rate effect (antibacterial activities) of the extract- bioactive components was examined to see if they have inhibitory effect on the selected test organisms using pour plating method. The FTIR method was performed on a spectrophotometer system which detects different characteristic peak values associated with various functional groups present the extracts. Results: All the isolates were susceptible to the extract with the number of the test organisms Original Research Article