Showing papers by "I. S. Bright Singh published in 2015"

Optimization of Culture Conditions for Mass Production of the Probiotics Pseudomonas MCCB 102 and 103 Antagonistic to Pathogenic Vibrios in Aquaculture

Abstract: Rapid growth of shrimp farming industry is affected by the recurrence of diverse diseases, among which vibriosis is predominant. Eco-friendly disease management strategy by the application of antagonistic probiotics is widely accepted. In the present study, culture conditions of antagonistic probiotics, Pseudomonas MCCB 102 and 103, were optimized to enhance their biomass production and antagonistic activity against the shrimp pathogen V. harveyi MCCB 111. Primarily, one-dimensional screening was carried out to fix the optimum range of sodium chloride concentration, pH and temperature. The second step optimization was done using a full-factorial central composite design of response surface methodology. As per the model, 12.9 g/L sodium chloride and pH 6.5 for Pseudomonas MCCB 102, and 5 g/L sodium chloride and pH 7 for Pseudomonas MCCB 103 were found to be ideal to maximize antagonistic activity. However, optimum temperature was the same (25 °C) for both isolates. Finally, the models were experimentally validated for enhanced biomass production and antagonistic activity. The optima for biomass and antagonistic activity were more or less the same, suggesting the possible influence of biomass on antagonistic activity.

Multifactorial interaction of growth factors on Penaeus monodon lymphoid cells and the impact of IGFs in DNA synthesis and metabolic activity in vitro

Abstract: Development of continuous cell lines from shrimp is essential to investigate viral pathogens. Unfortunately, there is no valid cell line developed from crustaceans in general and shrimps in particular to address this issue. Lack of information on the requirements of cells in vitro limits the success of developing a cell line, where the microenvironment of a cell culture, provided by the growth medium, is of prime importance. Screening and optimization of growth medium components based on statistical experimental designs have been widely used for improving the efficacy of cell culture media. Accordingly, we applied Plackett-Burman design and response surface methodology to study multifactorial interactions between the growth factors in shrimp cell culture medium and to identify the most important ones for growth of lymphoid cell culture from Penaeus monodon. The statistical screening and optimization indicated that insulin like growth factor-I (IGF-I) and insulin like growth factor-II (IGF-II) at concentrations of 100 and 150 ng ml(-1), respectively, could significantly influence the metabolic activity and DNA synthesis of the lymphoid cells. An increase of 53 % metabolic activity and 24.8 % DNA synthesis could be obtained, which suggested that IGF-I and IGF-II had critical roles in metabolic activity and DNA synthesis of shrimp lymphoid cells.

Molecular Characterization and Phylogenetic Analysis of Novel Isoform of Anti-lipopolysaccharide Factor from the Mantis Shrimp, Miyakea nepa.

Abstract: Anti-lipopolysaccharide factor (ALF) is a cationic anti-microbial peptide representing humoral defence system exhibiting a diverse spectrum of activity against microbial pathogens, including gram-negative and gram-positive bacteria, fungi, parasites and viruses. In this study, we identified and characterized a novel ALF homologue (MnALF) encoding cDNA sequence from the haemocytes of stomatopod mantis shrimp Miyakea nepa. The deduced peptide of MnALF encoded for a 123-amino acid peptide with a 25-residue signal peptide containing selenocysteine followed by a highly cationic mature peptide comprised of a putative LPS-binding domain flanked by two cysteine residues. BLAST analysis of MnALF showed that it exhibits identity to crustacean and limulid ALFs. The mature peptide of MnALF has a net charge of +7 and predicted molecular weight of 10.998 kDa with a theoretical isoelectric point (pI) of 9.93. Spatial structure of MnALF comprises three α-helices packed against a four-stranded β-sheet of which two were linked by a disulphide bond to form an amphipathic loop similar to the structure of Penaeus monodon, ALF-Pm3. All these features suggest that MnALF could play an imperative role in the innate defence mechanism of M. nepa. To our knowledge, this study accounts for the first report of an anti-microbial peptide from the order stomatopoda.

Investigations on semiconductor sonocatalysis for the removal of pathological micro-organisms in water

Abstract: Contamination of drinking water by bacterial pollutants is a major environmental problem. In the current study, the possibility of using zinc oxide-mediated sonocatalysis, as a potential advanced oxidation process for the removal of a major pollutant, i.e. Escherichia coli, is investigated. Critical parameters for optimum efficiency are identified. The organism deactivation is fully irreversible in the case of ZnO-mediated sonocatalysis. Scanning electron microscopy images show that morphological changes and cell-wall disruption of organisms are more in sonocatalysis compared to sonication alone. The deactivation is practically unaffected by initial pH in the range 5–9. Reactive oxygen species including in situ-formed free radicals play significant role in the deactivation. Sonoluminescence-induced photocatalysis is a major contributor in the disinfection process. A probable mechanism involving physical effects and semiconductor activation by ultrasound followed by the events leading to the deacti...

ISSN 2249-9687 Original Article Isolation, Purification and Characterization of Antimicrobial Peptides from Indian Ruff, Psenopsis cyanea (Alcock, 1890).

Abstract: Antimicrobial peptides are evolutionarily ancient, effector molecules of innate immune defense and are ubiquitously found in all kingdoms from bacteria to mammals, including fungi and plants. The present study deals with the isolation of antimicrobial peptides from marine bathydemersal fish Indian ruff, Psenopsis cyanea belonging to the family Centrolophidae and its in vitro antimicrobial activity. Peptides were extracted from the sample by modified acetic acidacetone precipitation method.The crude peptide extract exhibited antimicrobial activity against bacteria and fungi. Prepurification was done by solid phase extraction using Sep-Pak ® C- 18 cartridges and 40% Sep-Pak eluted fractions were subjected to FPLC using UNO TM QI column. Four fractions eluted on the basis of retention time were collected and further examined for antimicrobial activity by disc diffusion assay. FPLC fraction P40-1 was found to be active only against A. hydrophila and P40-2 was found to be active against Gram-positive and Gram-negative strains including S. aureus, B. cereus, and A. hydrophila. Whereas, P40-3 only showed inhibitory effect on A. hydrophila. Among the various fractions, P40-4 was the only fraction inhibited the growth of V. fluvialis. Active fractions were subjected to protein quantification. This is the first report on isolation and purification of AMPs from Psenopsis cyanea. © 2015 Universal Research Publications. All rights reserved

Molecular characterization and phylogenetic analysis of an anti-lipopolysaccharide factor from the crucifix crab, Charybdis feriatus

Abstract: m Abstract: Antimicrobial peptides are small cationic, gene-encoded, amphipathic, host defense peptides with a ubiquitous distribution in all living kingdoms. They are ,10 kDa in size, with 15-100 amino acids having a net positive charge of +2 to +9. Anti-lipopolysaccharide factor (ALF) is a cationic antimicrobial peptide which constitutes one of the key effector molecules in the innate immune system of crustaceans, and is capable of binding and neutralizing lipopoly- saccharides. In the present study, an ALF homolog (Charybdis feriatus (Cf)-ALF1)-encoding cDNA sequence from the hemocytes of the crucifix crab, C. feriatus, was cloned, identified, and characterized. The deduced peptide of Cf-ALF1 encoded for a 123 amino acid peptide with a 97 residue mature peptide (11.16 kDa) that had a net charge of +10. Two conserved cysteine residues and a putative lipopolysaccharide binding domain were observed in the Cf-ALF1 mature peptide. BLAST analysis of Cf-ALF1 nucleotides showed a 99% similarity to Scylla serrata. The spatial structure of Cf-ALF1 was composed of three α-helices packed against a four-strand β-sheet. Two of these helices were linked by a disulfide bond to form an amphipathic loop similar to the structure of anti-lipopolysaccharide factor isoform 3 from Penaeus monodon (ALF-Pm3). All these features suggest that Cf-ALF1 could play a significant role in the innate immune defense mechanism of C. feriatus.