Bioprospecting of Halotolerant Bacillus subtilis: A Study depicting its Potential Antimicrobial Activity against Clinically Important Pathogens

Akhila P Reghu,Aswin Thacharodi,Dilipkumar Thacharodi,G Kathikeyan,R Priyadharshini

doi:10.17485/ijst/2019/v12i22/144660

Abstract

Objectives: The current study focuses on characterization and isolation of bioactive compounds from a marine halophilic bacterium and testing its antimicrobial potentiality against clinically important pathogens like Proteus mirabilis, Salmonella typhi A, Salmonella typhi B, Pseudomonas aeruginosa and Klebsiella pneumoniae. The study also portraits presence of possible bioactive compounds responsible for such antimicrobial activity through Gas Chromatography-Mass Spectrometry (GC-MS). Methodology: Surface water samples were collected from Kovalam beach at Thiruvananthapuram, Kerala state, a South Indian coast of Indian peninsula and were screened for potential bacteria. Morphological, biochemical and molecular profiling were performed to identify and isolate the bacterium of interest. Antibiogram studies were conducted to understand pathogenic trends in the isolate. Culture supernatant of the test bacterium was screened against clinically important pathogens. Further, crude extract of the culture supernatant was subject to GC-MS analysis. Findings: Morphological, biochemical and molecular profiling of the isolate revealed the organism to be Bacillus subtilis. The culture supernatant had significant activity against clinically important pathogens. GC-MS analysis revealed possible antimicrobial compound to be (Pyrrolo [1, 2-a] pyrazine-1, 4-dione). Novelty: The study has significant importance as it depicts antimicrobial activity of halophiles against potent clinical pathogens. Keywords: Antibiogram Profiling, Bioactive Compounds, Gas Chromatography-Mass Spectrometry (GC-MS), Marine Halophiles, Molecular Profiling

Highlights

Over the past twenty years there has been an unprecedented rise in emergence of multidrug resistant bacterial strains in the field of medicine, making it laborious in the treatment process[1]
Bioprospecting of Halotolerant Bacillus subtilis: A Study depicting its Potential Antimicrobial Activity against Clinically Important Pathogens are turning to Multidrug Resistant (MDR) and are currently untreatable with commonly used antibiotics[3]
With recent discovery of resistance to colistin through MCR-1 genes, a mobile DNA which can be transferred among bacteria is raising questions on our situation to post antibiotic era[6]

Summary

Introduction

Over the past twenty years there has been an unprecedented rise in emergence of multidrug resistant bacterial strains in the field of medicine, making it laborious in the treatment process[1]. Bioprospecting of Halotolerant Bacillus subtilis: A Study depicting its Potential Antimicrobial Activity against Clinically Important Pathogens are turning to Multidrug Resistant (MDR) and are currently untreatable with commonly used antibiotics[3]. Horizontal gene transfer of resistant plasmids from the clinical pathogens has led to the emergence of MDR in environmental and clinical isolates. It would have taken place through transfer of plasmids, intergrons, genomic islands, insertion elements, mobile genetic elements or through bacteriophages[4]. Halophilic bacteria have been explored industrially and biotechnologically for its potentiality to produce different bioactive compounds with antitumor, anticancer, cytotoxic and antimicrobial activities[9]. Through GC-MS analysis we further predict the chemistry of possible bioactive compound responsible for its antimicrobial activity and lay footprints for scientist to explore further in characterization of this bioactive compound in future

Objectives

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Conclusion