In Vitro Assessment of Antimicrobial Activities of Ether and Hexane Extracts of microalgae Chlorella vulgaris against pathogenic bacteria

Increasing trends of drug-resistant strains of microorganisms especially bacteria have urged scientists to seek for antimicrobial compounds in natural resources with minimal or negligible side effects. Microalgae are one of these natural resources which are rich in active metabolites with potential use in pharmaceutical industries.
In this studyChlorella vulgaris was collected from microalgae collection of the International Sturgeon Institute- Rasht- Iran. Antibacterial activities of hexane and ether extracts of C. vulgaris against gram-positive bacterium Bacillus subtilis and Gram-negative bacterium Aeromonas hydrophila were evaluated. Algae was purely cultured to obtain the required volume and cell concentration for experiment and then the prepared biomass were extracted and Cannell et al. (1988) methods were used to examine antibacterial activities of hexane and ether extracts of the algae (1).
The results of the study approvedinhibitory properties of hexane and ether extracts of C. vulgaris against A. hydrophila and B. subtilis bacteria. The diameter of inhibition zone of hexane extract against B. subtilis and A. hydrophila, were 11-15.6 and 9.6- 11 mm and for ether extract were 12-18.6 and 7.6-16 mm respectively. Gas chromatography mass spectrophotometry was used to identify different substances in diethyl ether and hexane extracts. The main substances in ether extract included ketone compounds, esters, hydrocarbons, siloxane, Saylyl, terpenes and Hydrvsaylyl polyesters and in hexane extract the main substances were hydrocarbons, siloxane, Saylyl and Hydrvsaylyl are polyester.
Discussion and The inhibitory effect of ether extract was higher than the hexane extract therefore it could be used as a solvent to extract antimicrobial compounds.