Determination of fatty acids and proteins from the fresh water alga Chlamydomonas reinhardtii CC 2137 and its antagonism against aquatic bacteria

摘要

Chlamydomonas reinhardtii, a wild-type algal strain (CC 2137) was grown on tris acetate phosphate agar (TAP) medium. The growth curve values showed 2.0 logs till 6 days and declined thereafter. Later, the cells were harvested and extracted for fat using chloroform and methanol (2:1). The extract was hydrolyzed, lyzed and found to have unsaturated fatty acids like linolenic, linoleic, oleic acid, palmitoleic acid and saturated fatty acids viz. myristic, palmitic and stearic acid,using gas chromatography as well as mass spectrometry (GC-MS). Cell wall bound iron containing fatty acid elongation (FAE1) proteins of CC2137 were extracted and their size (ranging from 25-250 KD) was detected by SDS PAGE. The FAE1 protein was inhibitory to Bacillus cereus as evidenced by "Agar Spot Assay". Organic extracts of CC2137 cells with hot and cold extraction were tested against marine bacteria. In cold extraction, methanolic extracts showed highest inhibition (11.0 mm) to Vibrio harveyi (MM30) and subsequently acetone and ethyl acetate extracts showed inhibition to V. harveyi (MM32). In hot extraction, highest inhibitions were observed by ethanol and ethyl acetate (13.0 mm) to MM30 followed by methanol, ethanol and ethyl acetate extracts (12.0 mm) to MM32. Extracts of ethyl acetate and acetic acid showed maximum and identical inhibitions (8.0 mm) against Pseudomonas putida (PP) and lowest by methanoles and chloroform (6.0 mm) in cold extraction. Under hot extraction, the highest inhibition was shown by ethanol extract to PP followed by methanol and acetone (11.0 mm) and lowest by chloroform and acetic acid extracts (6.0 mm).