Journal of Environment and Sociobiology

Sayan Kamila ¹, Soumya Mondal ¹, Bidisha Chatterjee ¹, Bedaprana Roy ¹, Arup Kumar Mitra ¹

Affiliations
1 Department of Microbiology, St. Xavier’s College (Autonomous), Kolkata-70016., IN

Abstract

Soil salinity, a global issue, is a threat to the agricultural crops. The deposition of excess salt in the soil reduces the growth, development and yield of crops. Initially techniques like leaching and flushing were applied to reclaim such salt infested soil. However, the success rate was low and it greatly affected the agroecosystem. This had led to the search for saline tolerant and salt resistant crops. The sinking island of Ghoramara is also facing the problem of soil salinity. In this investigation, soil samples were collected from coastal, transition and agricultural region of the island and the physico-chemical parameters of the soil sample were analyzed to understand its quality. The parameters pH and EC were carefully analyzed since they are of utmost importance for elucidating soil salinity. Saline tolerant bacteria were isolated using increasing concentrations of salt in the growth medium. The isolated bacteria were grown on chrome agar followed by gram staining to identify the genus of the isolated bacteria. This was followed by the study of NPK fixation and solubilization analysis, zinc solubilizing efficiency and siderophore production i.e., iron chelating ability of the isolated strains. Based on the results obtained from the above set of experiments five bacteria were selected. These five bacteria would be identified using 16S rRNA. Further experiments for analyzing plant growth promoting hormone production and other plant growth promoting traits will be carried out with these five bacterial strains in the future. Depending on the result a consortium can be developed, specifically designed for the saline infested soil of Ghoramara to improve their crop productivity. Key words:

Keywords

Salt Tolerance, PGPR, Physico-Chemical Parameter, Soil Microflora.

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Debjani Dutta ¹, Debdatta Das ¹, Debapriya Maitra ¹, Bedaprana Roy ¹, Arup Kumar Mitra ¹

Affiliations
1 Department of Microbiology, St. Xavier’s College (Autonomous),30, Mother Teresa Sarani, Kolkata, West Bengal, India, Pin-700016., IN

Abstract

Spices impart flavor, taste and aroma to food. Spices have inherent microflora which may have varied roles and may interact variously amongst each other. Different spice samples were analyzed to isolate the indigenous microflora (bacteria and fungi). These isolates were purified. The colony characteristics and morphology of the isolates were studied and specific staining was performed to identify some selected isolates. Enzyme production ability of the selected bacterial isolates were assayed, and based on the absence of degradative enzymes, three harmless bacteria were tested against one of the fungal isolates, which was identified as Aspergillus flavus by partial sequencing. The antagonistic relationship between the fungi and the bacteria were carried out using plate assay method and three of the bacterial isolates were observed to be effective in controlling Aspergillus flavus. They were identified by partial sequencing and was found to be Bacillus australimaris, Bacillus subtilis and Bacillus cereus. The microbial enrichment may prove to be useful in terms of nutritive value addition to the spices and increase its shelf life.

Keywords

Aspergillus flavus, Bacillus australimaris, Bacillus subtilis, Bacillus cereus

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Sylvia Denis ¹, Ronit Dey ¹, Tanisha Chakraborty ¹, Sharanya Sreemani ¹, Paranjita Raha ¹, Arup Kumar Mitra ¹

Affiliations
1 Department of Microbiology, St. Xavier’s College (Autonomous) 30, Park Street, Mullick Bazar, Kolkata-700016., IN

Abstract

Role of climate and a proper gut flora prevalence walks hand in hand preventing from the onset of certain infections caused by food borne pathogenic bacteria. The plethora of microbes residing in the gut as “Sentinels of Defense” thereby maintaining an immune-homeostasis through complex microbial cross-talk with mucosal immune system of GI tract via integrated signalling and gene regulation is dominated by the climate induced micro-environment across the global population. In this study, we tried to bridge the connection between the country based sustaining climate and the role of commensal gut flora involved in outcompeting the ingested food-borne pathogens present in street food like Chowmein and meat, by posing restraints in nutrients and colonization space blocking the pathogenic I.D. Our study encompasses certain findings of different types of food borne pathogens in connection with raw Chowmein and Meat (raw) sample, related to the tropical climate of West Bengal, India compared with the in-silico research of Western Climate influencing the gut flora of the indigenous population following a completely different pattern of food habits. A hypothesis was made regarding the resilience of Indians towards food borne intoxication due to the sustaining tropical climate in comparison with the Western population based on two broad groups of microbes namely Prevotella sp and Bacteroid ssp as a consequence of totally different climate sustenance and discrete food habits followed in these two unique global locations.

Keywords

Microbiota, Street Food, Raw Meat, Contamination, Gut Flora.

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Meenakshi Mukhopadhyay ¹, Arup Kumar Mitra ², Debapriya Maitra ², Bedaprana Roy ², Archisman Chakraborty ³, Sudeshna Shyam Choudhury ², Indranath Chaudhuri ³

Affiliations
1 Department of Botany, Vivekananda College, Kolkata., IN
2 Department of Microbiology, St. Xavier’s College (Autonomous), Kolkata., IN
3 Department of Physics, St. Xavier’s College (Autonomous), Kolkata., IN

Abstract

Soil is a treasure trove of myriad microbial communities that encompass a bewildering array of physiological, metabolic, and genomic diversity essential for sustenance of soil fertility. Over-exploitation of arable lands with extensive use of agrochemicals has negatively impacted soil structure and function by lowering crop productivity. Such damaged agro-ecosystem can be recovered through restoration of microbial richness to replenish various plant-beneficial services at community level. Incorporation of potential single or multiple plant-growth promoting bacteria (PGPB) in soil is a unique strategy in modern sustainable agriculture. In this study, PGPB strains were isolated from a long-term used agricultural soil of Bahadurpur, West Bengal. Only the bacterial isolates having nitrogen, phosphorus and potassium acquisition ability were further screened for multiple plant growth promoting (PGP) traits. Isolates S3, S5, and R1 showed nitrogen-fixing, phosphate and potassium solubilizing ability. They were tested for production of IAA, GA, ACC deaminase, siderophore, biofilm, lytic enzymes, and volatile biochemical compounds under in vitro condition. Three most potent isolates (S3, S5 and R1) were selected for development of a multi-strain consortium to be utilized as bio-inoculant. Based on 16s rRNA gene sequence they were identified as Bacillus zhangzhouensis strain MMAM, B. cereus strain MMAM3, and B. subtilis strain MMAM2.

Keywords

Long-Term Used Agricultural Soil, Plan-Growth Promoting Bacteria, Multi-Strain Consortium, Bio-Inoculant.

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Shivashis Bikram Banerjee ¹, Debapriya Maitra ², Bedaprana Roy ², Bikram Dhara ², Ramalakshmi Datta ³, Sanjay Haldar ³, Arup Kumar Mitra ²

Affiliations
1 Post-Graduate Department of Biotechnology, St. Xavier’s College (Autonomous), Kolkata-700016., IN
2 Department of Microbiology, St. Xavier’s College (Autonomous), Kolkata-700016., IN
3 Vivekananda Institute of Biotechnology, South 24 Parganas, Pin-743 338, West Bengal, India., IN

Abstract

Increasing soil salinity acts as a major abiotic stress for crop plants. Increasing global temperatures are leading to greater evaporation from soil, along with change in rainfall patterns, which is resulting in reduced soil water availability for crop plants and increased soil salinity. Consequently, crop plants face water and nutrient shortage leading to yield losses. In fact, crop plants cannot be grown easily on such saline soil without some form of remediation. Plant Growth Promoting Rhizobacteria (PGPR) have shown prospective results in this regard. Halotolerant PGPRs have the ability to grow in such saline soils, while providing plant roots in the vicinity with growth nutrients and hormones. In the present study, we obtained six bacterial isolates from mangrove pneumatophores of Aegialitis rotundifoliaRoxb. and Ceriops tagal C. B. Rob. with associated rhizobial soil from Kshetra Mohanpur site in the Sundarbans of West Bengal. They were screened for salt tolerance, nitrogen fixation, phosphate solubilizing, potassium solubilizing and auxin synthesizing ability. Two of the six isolates showed all these properties. Hence, we propose their use as halotolerant PGPR biofertilizers for soil bioremediation.

Keywords

Plant Growth Promoting Rhizobacteria, Biofertilizer, Soil Salinity, Climate Change.

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