A comparative study on the antibiotic resistance pattern of soil bacterial communities in flood affected and unaffected areas of kothamangalam municipality Gopika Gopal, Nayomi John ⇑ Department of Microbiology, Mar Athanasius College, Kothamangalam, Kerala 686666, India article info Article history: Received 18 December 2019 Received in revised form 8 January 2020 Accepted 11 January 2020 Available online 1 February 2020 Keywords: Microorganism Antibiotic Pathogenicity Flood abstract Floods have remarkable effects on both above- and below-ground ecosystem processes. Soil microorgan- isms are very sensitive to environmental disturbances, and drastic changes in soil microbial community are expected from water logging conditions. Kothamangalam is one of the seriously flood affected region of Ernakulam district. Different bacterial species were isolated from rhizosphere and non-rhizosphere soils of flood affected and non-affected areas of Kothamangalam Municipality. The isolated bacterial strains were subjected to check their cultural and morphological characteristics, antibiotic sensitivity and pathogenicity pattern. The present study revealed the significant difference among strains, in their morphology, antibiotic sensitivity and pathogenicity pattern. Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Confer- ence on the Science and Technology of Advanced Materials. 1. Introduction Kothamangalam Municipality is one of the major severely flood affected area of Ernakulam district every year. Flooding of water causes immense damage to soil biodiversity and ecosystem. Micro- bial communities in the flood affected areas are temporally variable. Among them bacteria and fungi are the most sensitive [1]. Water logging causes variations in the antibiotic resistance and pathogenicity patterns of bacterial flora. These changes were stud- ied through a preliminary analysis of the morphological character- istics, drug resistance and hemolytic properties. In this study, heterotrophic bacteria from flood affected and unaffected areas (soil) of Kothamangalam municipality were isolated and analyzed. This is a comparative study which reveals the impact of flooding on drug resistance and pathogenic features of indigenous bacterial species. 2. Materials and methods 2.1. Isolation of total heterotrophic bacteria from flood affected and unaffected soil samples The soil samples were collected from five different places of flood affected and unaffected areas of Kothamangalam municipality, Ker- ala. These soil samples were used for the qualitative and quantita- tive bacteriological examination. Standard Plate Count (SPC) or Total Plate Count (TPC) method was adopted for the enumeration of total heterotrophic bacteria present in the soil samples [2]. 2.2. Enumeration of total heterotrophic bacteria from soil samples by standard plate count method [SPC] One gram of each soil sample was aseptically transferred to 10 ml of sterile physiological saline blank set and mixed thor- oughly. This gives a 10 times dilution (10 À1 ). 1 ml of the 10 À1 dilu- tion was transferred to second set of test tubes with 9 ml sterile water diluent. This gives 100 times dilution (10 À2 ). In a similar way dilutions were continued upto 10 À6 serially. 0.1 ml of sample from each dilution was aseptically transferred to sterile dried nutrient agar (NA) plates. The samples were carefully spreaded over the entire media surface using sterile L-rod. The plates were https://doi.org/10.1016/j.matpr.2020.01.272 2214-7853/Ó 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on the Science and Technology of Advanced Materials. ⇑ Corresponding author. E-mail address: nayomijohn10@gmail.com (N. John). Materials Today: Proceedings 25 (2020) 252–256 Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr