Microbial Community Level Physiological Profiles of Active Mud Volcano Soils in Andaman and Nicobar Islands

Abstract

The aim of this work was to determine if any differences exist in the community-level physiological profiles (CLPP) in different regions of mud volcano. The microbial functional diversity in the four soils sampled in the vicinity of a mud volcano, Baratang, Andaman and Nicobar Islands, India, was determined using Biolog EcoPlates. Comparisons of the patterns of substrate use showed differences in the community composition, reflecting the heterogeneous distribution of microorganisms in this environment. The results showed statistically significant differences among different volcanic environments both by total colony-forming unit and by average well colour development. On the basis of similarity percentage analysis, it was found that i-erythritol was the most commonly used substrate, but substrates such as dl-glycerol phosphate (end mud volcano × point mud volcano), l-asparagine (end mud volcano × dried mud volcano) and ketobutyric acid (outside mud volcano × point mud volcano) were found in only one environment. The metabolic diversity varied depending on the environments compared, indicating specific utilization of compounds’ effect. Microbial response in terms of the overall metabolic activity in outside mud volcano was higher than in other inside mud volcano soils. To the best of our knowledge, this is the first attempt to use CLPP study in volcanic environments in the Andaman and Nicobar Islands.