ANTIMICROBIAL AND ANTIOXIDANT ACTIVITY OF CHLAMYDOMONAS REINHARDTII SP

The present investigation was undertaken to study the antimicrobial and antioxidant activity in algae (Chlamydomonas reinhardtii CC 124). The extractions of metabolites were done by two methods (glass bead and steel ball) using methanol: chloroform: water (5:2:2) as solvents. The presences of metabolites were identified by thin layer chromatography and structural analysis was done by Gas Chromatography and Mass Spectrometry. Antimicrobial activities of the extracts were assessed against bacterial and fungal strains (Bacillus subtilis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Candida albicans, Aspergillus niger, Aspergillus flavus) by disc diffusion method and compared with standard antibiotics. The results, of both extracts showed more potent antimicrobial activity in (B. subtilis,P. aeruginosa, K. pneumoniae) bacterial species and (C. albicans) fungal strain. The antioxidant activity was tested by DPPH (2, 2-Diphenyl-1picrylhydrasyl) free radical method and determination of H2O2 radical scavenging activities were also performed. The presence of antioxidants was compared with commercial antioxidants, such as BHT (Butylated Hydroxy Toluene), BHA (Butylated Hydroxyl Anisole).The phenolic content was compared with gallic acid. From the present study, it can be concluded that the two different extracts of the algae has the antimicrobial and antioxidant activity. INTRODUCTION: Chlamydomonas is a genus of green alga, belonging to unicellular flagellates and has been used as a model organism in molecular biology, especially studies of flagellar motility, chloroplast dynamics, biogenesis, and genetics. Chlamydomonas species are known to produce high levels of galactose containing polysaccharides that can be hydrolyzed to produce monosaccharides . The production of extracellular antibiotic metabolites by marine algae has been well studied in recent years 2. Various strains of cyanobacteria are known to produce intracellular and extracellular metabolites with wide biological activities such as antialgal, antibacterial, antifungal and antiviral activity . Both cell extracts and extracts of the growth media of various unicellular algae (e.g. Chlorella vulgaris, Chlamydomonas pyrenoidosa) has proved to have antibacterial activity in vitro against both Grampositive and Gram-negative bacteria . It has also been reported that a wide range of antifungal activities were obtained from extracts of green algae, Diatoms and Dinoflagellates . Brown-algal polyphenols and phlorotannins worked as antioxidants, antibacterial and anti-algal compounds . Antioxidant compounds play an important role against various diseases (e.g., chronic inflammation, atherosclerosis, cancer and cardiovascular disorders) and ageing processes, which explains their considerable commercial potential in medicine, food production and the cosmetic industry .