Antimicrobial activities of certain seaweeds from muddy shore places of kerala

Selvaraju Raja Selvaraju Raja,Ephsy K Davis Ephsy K Davis,Samynathan M Samynathan M,Kalamani Velmurugan Kalamani Velmurugan,Karuppiah Kannan Karuppiah Kannan

doi:10.26524/krj.2021.16

Abstract

A study was carried out to reveal the growth inhibitory effect of methanol crude extract (MCE) and methanol supernatant extract (MSE) of sea weeds: 1) Gracillaria corticata, 2) Hypnea musciforms, 3) Gelidium micropterum and 4) Hypnea valentiae against six bacterial pathogens, 1) Pseudomonas aeruginosa, 2) Bacillus licheniformis, 3) Serratia marcescens, 4) Aeromonas hydrophila, 5) Acinetobacter baumanii, 6) Escherichia coli and two fungal strains, 1) Aspergillus niger and 2) Candida albicans respectively. Well diffusion method using zone of inhibition as indicator for growth inhibition was adopted. The results showed that methanol extracts of seaweeds viz., Gracillaria corticata, Hypnea musciforms, and Hypnea valentiae prevented the growth of pathogenic bacteria and fungi. The effect on growth was observed as zone of inhibition, the diameter of which was indicated in the units of a millimeter. The growth of the bacterium, Serratia marcescens was affected by methanol supernatant extract of the three types of seaweeds, Gracillaria corticata, Hypnea musciforms, and Hypnea valentiae, and by the methanolic crude extract of Hypnea musciforms and Hypnea valentiae. However, the growths of other species of bacteria were not controlled by either of the extracts of the seaweeds except, Bacillus licheniformis which was controlled by only Gracillaria corticata. The growth of fungi: Aspergillus niger and Candida albicans were inhibited by the methanol extracts of Gracillaria corticata. Between the two forms of methanolic extracts i.e., supernatant and crude, the efficiency of the supernatant extract was greater than that of crude one. Further, among the three types of seaweeds which showed an effect on the growth of microbes, the level of the zone of inhibition caused by Gracillaria corticata was statistically higher than that of the other two, Hypnea musciforms, and Hypnea valentiae.

Highlights

Various natural antimicrobial compounds have been recorded in a marine environment more than those in the terrestrial one
Diameter of Zone of inhibition as was in the range between 11and 5mm, the observed in culture media of pathogenic bacteria, microbe was noted as intermediate in response to Serratia marcescens treated with methanol extract the type of seaweed used
The growth of a bacterium, Serratia marcescens was affected by methanol extract supernatant of the three types of seaweeds, Gracillaria corticata, Hypnea musciforms, and Hypnea valentiae, and by the crude methanolic extract of Hypnea musciforms and Hypnea valentiae (Fig. 1&2)

Summary

INTRODUCTION

Various natural antimicrobial compounds have been recorded in a marine environment more than those in the terrestrial one Marine organisms such as marine algae are source materials for structurally unique natural products with pharmacological and biological activities. Of cytostatic, antiviral, anthelmintic, antifungal, and diseases To overcome this problem, new therapeutic antibacterial activities compounds in green, brown, drugs from natural products have been explored and red algae with cytostatic, antiviral, anthelmintic, [16]. Marine algae have been extensively antifungal, and antibacterial activities [6] Seaweeds documented for their capacity to provide a rich are considered to be the main source of bioactive source of primary and secondary metabolites [17]. 40 μg/ml, 60 μg/ml and 80 μg/ml) using methanol. a zone of inhibition in the medium of Bacillus licheniformis of 11 mm around the well provided

Test pathogens with crude methanol extract at a concentration of

RESULTS

Comparative account of the effect of seaweeds on microbes

Findings

DISCUSSION

CONCLUSION