Browsing by Author "Jha, Prabhat N."

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Advances in Biotechnology: A Practical Approach (Biotechnology in Agriculture, Industry and Medicine)
(‎ Nova Science Publishers, 2013) Jha, Prabhat N.
Biotechnology is the use of living organisms to enhance products, our lives and our environment. It is a broad and complex discipline that encompasses many specialised areas. The promise that biotechnology holds for developing countries is well recognised and it is an important tool that can be applied to diverse economic sectors with a focus on the production of food crops, livestock management, human health care, the chemical industry and environmental management. This book covers applications of biotechnology in selected areas such as health care, agriculture, microbial systems, "in silico" analysis for drug designing and drug discovery and the environment
Alleviation of salinity-induced damage on wheat plant by an ACC deaminase-producing halophilic bacterium Serratia sp. SL- 12 isolated from a salt lake
(Springer, 2016-02) Jha, Prabhat N.
Plant growth promoting bacteria (PGPB) with 1-aminocyclopropane-1-carboxylate deaminase (ACC deaminase) activity can be used to ameliorate salt stress in plants. The aim of this study was to characterize a salt-tolerant PGP bacterium Serratia sp. SL-12 isolated from a salt lake, and to evaluate its capability to promote growth in wheat plants (Triticum aestivum L) under conditions of salt stress. The isolate SL-12 exhibited other plant growth promoting properties such as the production of indole-3-acetic acid, and enabling solubilization of inorganic phosphate. An analysis of fatty acid composition of the isolate grown at different salt concentrations (150–200 mM) indicated that salt concentration strongly influenced the fatty acid composition, and increased the proportion of unsaturated fatty acids. Inoculation of SL-12 into wheat plants growing under salt stress (150–200 mM NaCl) resulted in a significant increase in plant growth, as measured by parameters such as shoot/root length, fresh/dry weight, and photosynthetic pigment accumulation. In addition, application of isolate SL-12 decreased the levels of Na+ by (65 %) and increased the uptake of K+ by (39 %), indicating a role in maintaining ionic homeostasis, and minimizing toxic ionic effects in host wheat plants. The growth of wheat seedling under salinity stress was improved by SL-12 by inducing accumulation of osmolytes such as total soluble sugar and total protein content, while reducing the salt-induced malondialdehyde content. This has been found by other researchers. The present study indicates the potential of isolate SL-12 as a biofertilizer for enhancing the growth of wheat and other crops under salt stress conditions.
Analysis of fatty acid composition of PGPR Klebsiella sp. SBP-8 and its role in ameliorating salt stress in wheat
(Springer, 2017) Jha, Prabhat N.
A halotolerant plant-growth-promoting rhizobacteria (PGPR) can ameliorate salt stress in associated plants by various mechanisms. Therefore, the present study aimed to characterize a PGPR Klebsiella sp. SBP-8 for its ability to tolerate salt stress and to study the mechanism of PGPR-mediated mitigation of salt stress in the wheat plant. The abiotic stressors result in multiple changes in the fatty acid composition of Klebsiella sp. SBP-8, helping the membrane to keep its integrity, fluidity, and function for its growth under salt (NaCl) stress conditions. The changes in fatty acid composition of test organism were analyzed by fatty acid methyl ester (FAME) analysis under varying saline conditions. The spectroscopy (GC-MS) profile of cell extract at different salt concentrations was comprised of hydrocarbons, and fatty alcohols with varying carbon chain length. Inoculation of Klebsiella sp. SBP-8 to wheat seedling showed increase in proline, total soluble sugar, and total protein content of treated plants. Bacterial inoculation also decreased the concentration of salinity-induced malondialdehyde (MDA) content. In addition, bacterial inoculation also increased the various antioxidative enzymes like superoxide dismutase (SOD), catalase (CAT), and peroxidase (POX) in treated plants. It is likely that bacterial inoculation alleviated the salt stress to wheat plant by co-ordination of antioxidative machinery, and improvement in osmolyte contents. Therefore, the present study suggests that bacterial-inoculated wheat plants were able to cope better with salt stress than uninoculated control, therefore it can serve as a promising bio-inoculant for enhancing the growth of wheat like cereal crops under saline stress.
Assessment of mineral phosphate-solubilizing properties and molecular characterization of zinc-tolerant bacteria
(Wiley, 2012) Jha, Prabhat N.
Plant growth-promoting bacteria with the ability to tolerate heavy metals have importance both in sustainable agriculture and phytoremediation. The present study reports on the isolation and characterization of mineral phosphate-solubilizing (MPS) bacteria associated with the Achyranthes aspera L. plant (prickly chaff, flower plant). Out of 35 bacterial isolates, 6 isolates, namely RS7, RP23, EPR1, RS5, RP11 and RP19, with high MPS activity were selected and subjected to the assessment of MPS activity under various stress conditions, viz. ZnSO4 (0.30–1.5 M), NaCl and temperature. MPS activity by the selected isolates was observed at concentrations of as high as >1.2 M ZnSO4. Significant improvement in plant growth was observed on bacterization of seeds (pearl millet) with all of the six selected isolates. Plant growth was measured in terms of root length, shoot length, fresh weight and % increase in root biomass. The molecular diversity among the phosphate-solubilizing bacteria was studied employing enterobacterial repetitive intergenic sequence-PCR (ERIC-PCR). Representative strains from each ERIC type were identified, on the basis of a partial sequence of the 16S rRNA gene, as members of the genera Pseudomonas, Citrobacter, Acinetobacter, Serratia, and Enterobacter. Among all the isolates, RP19 was the best in terms of phosphate-solubizing activity and its response to various stresses. The ability of RP19 and other isolates to exhibit MPS activity at high ZnSO4 concentrations suggests their potential as efficient biofertilizer for growing plants in metal (ZnSO4)-contaminated soil. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Association of Rhizospheric/Endophytic Bacteria with Plants: A Potential Gateway to Sustainable Agriculture
(Greener Journals, 2013) Jha, Prabhat N.; Mehrotra, Rajesh
Application of associative bacteria for sustainable agriculture holds immense potential. These bacteria are known to enhance growth and yield of plants by fixing atmospheric nitrogen, solubilization of phosphate, production of phytohormones and siderophores, possession of antagonistic activity as well as reducing the level of stress ethylene in host plants. Colonization of these bacteria can be tracked by tagging them with certain molecular markers such as β-glucuronidase (gus) or green fluorescent protein (gfp) followed by electron microscopy or laser scanning confocal microscopy. Associative bacteria and endophytes may express genes differentially to colonize and establish the plant interior. They may also use ‘quorum sensing’ molecules for colonization process. Present review aims to highlight various plant growth promoting properties, ecology and updates of molecular mechanisms involved in interaction between associative bacteria and plants as well as immune responses triggered by these bacteria in plants.
Association of Rhizospheric/Endophytic Bacteria with Plants: A Potential Gateway to Sustainable Agriculture
(Greener Journals, 2013) Jha, Prabhat N.; Mehrotra, Rajesh
Application of associative bacteria for sustainable agriculture holds immense potential. These bacteria are known to enhance growth and yield of plants by fixing atmospheric nitrogen, solubilization of phosphate, production of phytohormones and siderophores, possession of antagonistic activity as well as reducing the level of stress ethylene in host plants. Colonization of these bacteria can be tracked by tagging them with certain molecular markers such as β-glucuronidase (gus) or green fluorescent protein (gfp) followed by electron microscopy or laser scanning confocal microscopy. Associative bacteria and endophytes may express genes differentially to colonize and establish the plant interior. They may also use ‘quorum sensing’ molecules for colonization process. Present review aims to highlight various plant growth promoting properties, ecology and updates of molecular mechanisms involved in interaction between associative bacteria and plants as well as immune responses triggered by these bacteria in plants.
Bio-inoculation of Plant Growth-promoting Rhizobacterium Enterobacter cloacae ZNP-3 Increased Resistance Against Salt and Temperature Stresses in Wheat Plant (Triticum aestivum L.)
(Springer, 2017) Jha, Prabhat N.
Bacteria residing in the rhizosphere and capable of host plant growth stimulation (PGPR) through ACC-deaminase activity can ameliorate various biotic- and abiotic-stress conditions by decreasing the level of ‘stress ethylene’ in plants. The present study aimed to evaluate the effect of a PGPR strain Enterobacter cloacae ZNP-3 in augmenting wheat plant growth under salinity- and temperature-stress conditions. Among the plant growth-promoting (PGP) traits, the test organism produced ACC deaminase along with several other properties namely indole-3-acetic acid (IAA) production, mineral phosphate solubilization, hydrogen cyanide (HCN) and ammonia production. The test isolate illustrated its ability to function as a biocontrol agent as it displayed antagonistic activity against a wide range of bacterial and fungal pathogens. Its inoculation to wheat plant resulted in a considerable increase in growth parameters, biomass, and chlorophyll content under salinity stress. The inoculation also decreased the accumulation of Na+ and increased K+ uptake in shoots and roots, leading to maintenance of favorable K+/Na+ ratios in bacterial-treated plants for alleviating the toxic effect of salt stress. Moreover, application of ZNP-3 also stimulated the growth of wheat plants in terms of higher biomass and other growth parameters under temperature-stress conditions. Elevated levels of various compatible solutes following inoculation significantly alleviated the negative effect of salinity stress. The inoculation of isolate ZNP-3 also minimized salinity-induced oxidative damage by lowering H2O2 and O2 − contents. Moreover, the colonization behavior of the isolate illustrates its endophytic nature. The observed results indicate that the isolate Enterobacter cloacae ZNP-3 mitigates the detrimental effects of salinity and temperature stressors, and can be used as a promising bioinoculant to decrease the deleterious effects caused by salinity and other stressors.
Biochemistry and genetics of ACC deaminase: a weapon to “stress ethylene” produced in plants
(Frontiers, 2015-09) Jha, Prabhat N.; Kumar, Anil
1-aminocyclopropane-1-carboxylate deaminase (ACCD), a pyridoxal phosphate-dependent enzyme, is widespread in diverse bacterial and fungal species. Owing to ACCD activity, certain plant associated bacteria help plant to grow under biotic and abiotic stresses by decreasing the level of “stress ethylene” which is inhibitory to plant growth. ACCD breaks down ACC, an immediate precursor of ethylene, to ammonia and α-ketobutyrate, which can be further metabolized by bacteria for their growth. ACC deaminase is an inducible enzyme whose synthesis is induced in the presence of its substrate ACC. This enzyme encoded by gene AcdS is under tight regulation and regulated differentially under different environmental conditions. Regulatory elements of gene AcdS are comprised of the regulatory gene encoding LRP protein and other regulatory elements which are activated differentially under aerobic and anaerobic conditions. The role of some additional regulatory genes such as AcdB or LysR may also be required for expression of AcdS. Phylogenetic analysis of AcdS has revealed that distribution of this gene among different bacteria might have resulted from vertical gene transfer with occasional horizontal gene transfer (HGT). Application of bacterial AcdS gene has been extended by developing transgenic plants with ACCD gene which showed increased tolerance to biotic and abiotic stresses in plants. Moreover, distribution of ACCD gene or its homolog's in a wide range of species belonging to all three domains indicate an alternative role of ACCD in the physiology of an organism. Therefore, this review is an attempt to explore current knowledge of bacterial ACC deaminase mediated physiological effects in plants, mode of enzyme action, genetics, distribution among different species, ecological role of ACCD and, future research avenues to develop transgenic plants expressing foreign AcdS gene to cope with biotic and abiotic stressors. Systemic identification of regulatory circuits would be highly valuable to express the gene under diverse environmental conditions.
Biocontrolling and Colonization Potential of Pseudomonas Aeruginosa PM389 Isolated from Pennisetum Glaucum under Field Conditions
(IJREST, 2015) Jha, Prabhat N.
Present study reports further characterization of the endophytic bacteria Pseudomonas aeruginosa PM389 for their biocontrol properties and traits required for endophytic colonization on the basis of earlier preliminary results. Biocontrol, endophytic, plant growth promoting properties of PM389 were further tested by challenging plant with fungal pathogen Fusarium oxysporum causing root rot of wheat under in vitro condition. PM389 showed positive results for multiple mechanisms of antagonism against important fungal pathogens. Several traits required for endophytic colonization like different kinds of motility, biofilm formation, EPS production tested were present in PM389. Furthermore, results of biocontrol studies conducted in vitro showed significant increase in shoot length (37%) of Fusarium oxysporum challenged wheat seedlings pretreated with P. aeruginosa PM389 as compared to control. With various plant growth promoting properties, endophytic traits, biocontrol mechanisms against plant pathogenic microorganisms, it establishes that P. aeruginosa PM389 can serve as a potential biofertilizer and a biocontrol agent.
Biodiesel production through lipase catalyzed transesterification: An overview
(Elsiever, 2010) Jha, Prabhat N.; Mehrotra, Rajesh
Recently, with the global shortage of fossil fuels, excessive increase in the price of crude oil and increased environmental concerns have resulted in the rapid growth in biodiesel production. The central reaction in the biodiesel production is the transesterification reaction which could be catalyzed either chemically or enzymatically. Enzymatic transesterification has certain advantages over the chemical catalysis of transesterification, as it is less energy intensive, allows easy recovery of glycerol and the transesterification of glycerides with high free fatty acid contents. Limitations of the enzyme catalyzed reactions include high cost of enzyme, low yield, high reaction time and the amount of water and organic solvents in the reaction mixture. Researchers have been trying to overcome these limitations in the enzyme catalyzed transesterification reaction. This paper is meant to review the latest development in the field of lipase catalyzed transesterification of biologically derived oil to produce biodiesel.
Biological evaluation and structure activity relationship of 9-methyl-1-phenyl-9H-pyrido[3,4-b]indole derivatives as anti-leishmanial agents
(Elsiever, 2019) Jha, Prabhat N.; Murugesan, Sankaranarayanan
A series of piperazinyl-β-carboline-3-carboxamide derivatives were designed through a molecular hybridization approach. Designed analogues were synthesized, characterized and evaluated for anti-leishmanial activity against Leishmania infantum and Leishmania donovani. In L. infantum inhibition assay, compounds 7d, 7g and 7c displayed potent inhibition of promastigotes (EC50 1.59, 1.47 and 3.73 µM respectively) and amastigotes (EC50 1.4, 1.9 and 2.6 µM respectively). SAR studies revealed that, para substitution of methoxy, chloro groups and methyl group on ortho position favored anti-leishmanial activity against L. infantum. Among these analogues 7d, 7h, 7n and 7g exhibited potent inhibition against L. donovani promastigotes (EC50 0.91, 4.0, 4.57 and 5.02 µM respectively), axenic amastigotes (EC50 0.9, 3.5, 2.2 and 3.8 µM respectively) and intracellular amastigotes (EC50 1.3, 7.8, 5.6 and 6.3 µM respectively). SAR studies suggested that, para substitution of methoxy group, para and meta substitution of chloro groups and benzyl replacement recommended for significant anti-leishmanial against L. donovani.
Characterization and Optimization of Alkaline Protease Production from Bacillus licheniformis HSW-16 Isolated from Sambhar Salt Lake
(IJASB, 2015) Jha, Prabhat N.
Halophilic microorganisms are recognized as potential source of secondary metabolites including enzymes and drugs with wide agricultural and industrial applications. In the present study protease producing halotolerant bacterium Bacillus licheniformis HSW-16 was isolated from hypersaline Sambhar lake, Rajasthan India. Protease production was performed by using azocasein as substrate. Confirmation of protease production was also done by amplification of alkaline protease gene and sequencing. The various nutritional factors such as carbon and nitrogen source and other physiological parameters like pH, temperature, incubation time and agitation speed were optimized for optimum protease production. The enzyme was active in pH range 7-10, temperature 25 °C-40 °C and salt concentration of 1.5M. The characteristics demonstrated by this isolate showed that it could be used as a potential source of enzyme.
Characterization of Novel Plant Growth Promoting Endophytic Bacterium Achromobacter xylosoxidans from Wheat Plant
(Springer, 2009) Jha, Prabhat N.
Nine diazotrophic bacteria were isolated from surface-sterilized roots and culms of wheat variety Malviya-234, which is grown with very low or no inputs of nitrogen fertilizer. Out of the nine bacteria, four showed indole acetic acid (IAA) production, and five were positive for P solubilization. One isolate, WM234C-3, showed appreciable level of nitrogenase activity, IAA production, and P solubilization ability, and was further characterized with a view to exploiting its plant growth promoting activity. Based on 16S rDNA sequence analysis, this isolate was identified as Achromobacter xylosoxidans. Diazotrophic nature of this particular isolate was confirmed by Western blot analysis of dinitrogenase reductase and amplification of nifH. Analysis of the nifH sequence showed close homology with typical diazotrophic bacteria. Endophytic nature and cross-infection ability of WM234C-3 were tested by molecular tagging with gusA fused to a constitutive promoter followed by inoculation onto rice seedlings in axenic conditions. At 21 days after inoculation, the roots showed blue staining, the most intense color being at the emergence of lateral roots and root tips. Microscopic observation confirmed colonization of gus-tagged WM234C-3 in the intercellular spaces of cortical as well as vascular zones of roots. Inoculation of gus-tagged WM234C-3 to rice plants resulted in significant increase in root/shoot length, fresh weight, and chlorophyll a content. Plant growth promoting features coupled with cross-infection ability suggest that this endophytic bacterium may be exploited as agricultural agent for various crops after a thorough and critical pathogenicity test.
ChemInform Abstract: Novel Grinding Synthesis of Pyranopyrazole Analogues and Their Evaluation as Antimicrobial Agents.
(Wiley, 2016) Jha, Prabhat N.; Shukla, Paritosh
Compounds are prepared and screened for their antibacterial and antifungal activities
Click chemistry inspired synthesis of piperazine-triazole derivatives and evaluation of their antimicrobial activities
(Springer, 2015) Jha, Prabhat N.; Kumar, Anil
A series of novel piperazine-1,2,3-triazole derivatives, which entailed the bioisosteric replacement of the imidazole moiety and hybridization of two drug scaffolds was prepared by employing the regioselective copper (I)-catalysed azide-alkyne 1,3-dipolar cycloaddition reaction. The synthesized compounds were evaluated for antibacterial activities against Gram-negative (E. Coli and P. Putida), Gram-positive S. Aureus bacteria and fungicidal activities against F. oxysporum, F. gramillarium and F. monalliforme fungi. Compound 7ac′ exhibited moderate but promising antibacterial activity against Gram-negative bacteria and fungicidal activity against F. oxysporum and F. gramillarium.
CO2 sequestration potential of halo-tolerant bacterium Pseudomonas aeruginosa SSL-4 and its application for recovery of fatty alcohols
(Elsiever, 2017-10) Jha, Prabhat N.; Mishra, Somesh; Gupta, Suresh; Raghuvanshi, Smita
Bio-mitigation of CO2 utilizing prokaryotes and simultaneous extraction of valuable bio-molecule is fast gaining interest now-a-days. Present work discusses the thermodynamic assessment of CO2 bio-mitigation capability of Pseudomonas aeruginosa SSL-4 isolated from halo alkalophilic habitat in the absence of light. The maximum specific growth (μMax, h−1) of isolate was found to be 0.425 (±0.0025) and 0.34 (±0.0063) at 3% (w/v) salt concentration and 35 °C, respectively. The isolate was cultivated in the environment having initial CO2 (g) concentration of 17(±0.8) % (v/v) using Fe[II] as an energy source (0, 50 and 100 ppm) for evaluating CO2 fixing ability of microorganisms. The maximum CO2 removal efficiency of 92.37 (±2.46) % (v/v) was obtained at 100 ppm of Fe[II] concentration. The isolate has shown the maximum CO2 fixation rate () of 0.04 (±0.003) and 0.06 (±0.001) g/L/d at 50 and 100 ppm of Fe[II] concentration, respectively. FT-IR and GC–MS analysis of obtained leachate revealed the presence of fatty alcohols (C12–C28) and total product recovery (C12–C18) of 0.371 g per g of biomass. The thermodynamic assessment revealed the actual CO2 utilization efficiency of 41.16%. Thus, the isolated strain from extreme hyper saline environment has shown the potential for research dedicated to carbon capture and utilization.
Current Topics in Biotechnology & Microbiology
(LAMBERT Academic Publishing, 2011) Jha, Prabhat N.
Welcome to Current Topics in Biotechnology and Microbiology. This book provides the basics as well as new ideas in Biotechnology and Microbiology in a narrative and lucid style. The modern techniques employed in Nano-biotechnology, Genetic Engineering, Biotechnology and Microbiology are discussed in a comprehensive manner which will update the readers of Biotechnology and Microbiology field. This book is aimed to develop scientific and research skill along with the basic knowledge in the undergraduate and postgraduate students.
Deducing the Bio-Perspective Capabilities of Fe(II) Oxidizing Bacterium Isolated from Extreme Environment
(BAB, 2015) Jha, Prabhat N.; Mishra, Somesh; Raghuvanshi, Smita; Gupta, Suresh
Rigorous utilization of chemical fertilizers, monoculture and irrigation with surface saline water is globally deteriorating the quality of surface soil. In present work, the halo and alkalo tolarent bacterium strain isolated from extreme environment, was explored for producing plant growth hormones, that could be used for salt stress up gradation of the crops. The 16S rRNA gene sequencing was used for analysis of salt tolerant bacterium. The bacterium was identified as Pseudomonas aeruginosa KP163922. The Pseudomonas aeruginosa KP 163922 showed plant growth promotion traits, production of industrially important enzymes (amylase, protease and cellulase) and tolerance to more than 4% NaCl. The antagonistic test reveals that, the growth of pathogenic gram negative bacterium E. coli and Pseudomonas putida was repressed by Pseudomonas aeruginosa KP163922
Design and Synthesis of Imidazo/Benzimidazo[1,2-c]quinazoline Derivatives and Evaluation of Their Antimicrobial Activity
(ACS, 2018) Jha, Prabhat N.; Kumar, Anil
A new class of fused quinazolines has been designed and synthesized via copper-catalyzed Ullmann type C–N coupling followed by intramolecular cross-dehydrogenative coupling reaction in moderate to good yields. The synthesized compounds were tested for in vitro antibacterial activity against three Gram negative (Escherichia coli, Pseudomonas putida, and Salmonella typhi) and two Gram positive (Bacillus subtilis, and Staphylococcus aureus) bacteria. Among all tested compounds, 8ga, 8gc, and 8gd exhibited promising minimum inhibitory concentration (MIC) values (4–8 μg/mL) for all bacterial strains tested as compared to the positive control ciprofloxacin. The synthesized compounds were also evaluated for their in vitro antifungal activity against Aspergillus niger and Candida albicans and compounds 8ga, 8gc, and 8gd having potential antibacterial activity also showed pronounced antifungal activity (MIC values 8–16 μg/mL) against both strains. The bactericidal assay by propidium iodide and live–dead bacterial cell screening using a mixture of acridine orange/ethidium bromide (AO/Et·Br) showed considerable changes in the bacterial cell membrane, which might be the cause or consequence of cell death. Moreover, the hemolytic activity for most potent compounds (8ga, 8gc, and 8gd) showed their safety profile toward human blood cells.
The draft genome sequence of the plant growth promoting rhizospheric bacterium Enterobacter cloacae SBP-8
(Elsiever, 2017-06) Jha, Prabhat N.
Here, we report the draft genome sequence and annotation of plant growth promoting rhizobacterium Enterobacter cloacae SBP-8 isolated from the rhizosphere of Sorghum bicolor L. growing in desert region of Rajasthan, India. From the genome sequences, we identified the genes encoding plant growth promoting properties such as 1-aminocyclopropane-1-carboxylate deaminase (AcdS), phosphate solubilisation, siderophore, and IAA (indole acetic acid) production. The genes encoding different functions required for colonization including motility, chemotaxis, adherence, and secretion system (I, II, IV, VI) were also identified. The complete genome sequence of this bacterium consists of one chromosome (48,54,065 bp) and one plasmid (85,398). The genome sequence of Enterobacter cloacae SBP-8 was deposited in the Genbank with the accession number CP016906 (chromosome) and CP017413 (plasmid).