Venkatesan Arul

• Doctor of Philosophy
• Professor at Pondicherry University

In this study, fermented rice gruel, a traditional food in South Telangana, India, was used as a source for the isolation of biologically significant probiotics. A total of 56 morphologically diverse strains were isolated and screened for their ability to inhibit dental biofilms as well as foodborne and aquaculture bacterial pathogens. Among these,...

This study documents the effect of cryopreservation on motility, DNA integrity, and gene expression in Mugil cephalus sperm. Fresh sperm were cryopreserved using V2 extender (V2E) or 0.3 M glucose, each in combination with one of three cryoprotective agents (CPAs), i.e., 10 % of dimethylsulfoxide, ethylene glycol, or glycerol, all at once. After tw...

The goal of this research was to determine the effect of dietary supplementation of vitamin C-loaded chitosan nanoparticles (VC-CSNPs) on the antioxidant activity, disease resistance, non-specific immunity, and gene expression of the whiteleg shrimp Litopenaeus vannamei which was fed for eight weeks and challenged with Vibrio harveyi. Antioxidants...

In this study, the plate casting method was successfully used to prepare biocomposite films containing EPS from probiotic Enterococcus faecium MC-5 in combination with PVA and chitosan. The findings demonstrated that EPS was uniformly distributed in the film matrices and significantly improved the physicochemical properties of the resulting composi...

In this study, we optimized a simple method of cryopreservation for Mugil cephalus sperm based on post-thaw motility and viability. A series of experiments were conducted by changing the extender, cryoprotectant and freezing height above the liquid nitrogen (LN) surface. First, we carried out the cryopreservation using the extender V2E and cryoprot...

Rhizophora mucronata Leaves Polysaccharide (RMLP) was extracted and purified from the mangrove Rhizo-phora mucronata leaves by anion-exchange and size-exclusion column chromatography. Physicochemical characterization of RMLP was evaluated by spectrtoscopic analysis (FT-IR, 1 H & 13 C NMR) and RP-HPLC. The molecular weight of RMLP was found to be 2....

In every century of history, there are many new diseases emerged, which are not even cured by many developed countries. Today, despite of scientific development, new deadly pandemic diseases are caused by microorganisms. Hygiene is considered to be one of the best methods of avoiding such communicable diseases, especially viral diseases. Illness ca...

The selenium nanoparticles (SeNPs) linked with exopolysaccharide (EPS) of E. faecium MC-5 were successfully produced. UV–Vis spectra, DLS, zeta potential, SEM, TEM, FT-IR, thermogravimetric analysis-DSC, and X-ray diffraction measurements were used to characterize the SeNPs in terms of formation, size, stability, and functional group attachment, mo...

E. faecium MC-5 was isolated and characterized from the gut content of C. carpio and supplemented with a pellet diet at the ratio of 1.0 × 10⁶, 1.0 × 10⁹, and 1.0 × 10¹² cfu g–1. Then it was fed to Cirrhinus mrigala for 42 days and the growth performances were evaluated. The growth performance of experimental groups was significantly (P < 0.05) inc...

Background Selenium (Se) is considered an important micronutrient for human and animal health having potential biological functions and it is required for the prevention and treatment of diseases. The present study was designed to optimize the synthesis conditions of selenium nanoparticles by the Taguchi design method using sodium selenite as a pre...

A gene encoding lipase enzyme from Bacillus flexus PU2 was cloned and expressed in E. coli BL21 (DE3) pLysS and purified protein having the molecular weight of 34 kDa. This lipase was found to be alkaline (pH 9) and slightly thermophilic. This lipase was observed to retain its activity in the presence of methanol, ethanol, DMSO, and acetone. Ferrou...

In this study, we developed a simple and robust method of cryopreservation of sperm in Mugil cephalus. A series of experiments were conducted to develop a simplified method by changing the extender, cryoprotectant and freezing height above the liquid nitrogen (LN2) surface. Fresh sperm were diluted 1:1 in a cryomedium (cryomedium = extender + cryop...

Avicennia marina mangrove leaves polysaccharide (AMLP) was used for the synthesis of polysaccharide-based selenium (AMLP-SeNPs) and silver nanoparticles (AMLP-AgNPs). The synthesized nanoparticles were further characterized by UV-Vis, DLS, FT-IR, X-ray diffraction, and HR-TEM analysis. A 60-day (8 weeks) feeding trial experiment was conducted to in...

The lipase gene from Psychrobacter celer PU3 was cloned into pET-28a(+) expression vector and overexpressed in E. coli BL21 (DE3) pLysS cells. The purified Psychrobacter celer lipase (PCL) was characterized as an alkaline active enzyme and has a molecular mass of around 30 kDa. The PCL was active even at a low temperature and the optimum range was...

In the present study, Enterococcus faecium MC-5 isolated from the fish gut was cultured in the MRS broth to produce exopolysaccharide (EPS). The maximum EPS production was optimized using Response Surface Methodology (RSM) with three different factors which include sucrose, ammonium nitrate and pH. RSM result predicted that maximum EPS (16.48 g/L)...

The present work is carried out to determine the biodegradation potential of n-hexadecane by bacterial strain P. aeruginosa PU1 isolated from soil polluted with transformer oil. The bacteria showed its ability to grow in n-hexadecane containing medium and its utilization was revealed by a 2, 6-dichlorophenol indophenol assay, where complete decolou...

A low molecular weight polysaccharide, the AMLP was isolated from the leaves of Avicennia marina and sequentially purified using DEAE-Sepharose fast flow and size exclusion chromatography. Monosaccharide analysis suggested that AMLP is mainly composed of fucose (38.34 %), galactose (30.16 %), mannose (13.32 %), and rhamnose (18.18 %). IR spectrosco...

In the present work, a probiotic bacteria Weissella cibaria MD2 was used for the production of exopolysaccharide (EPS), which was characterized and evaluated for several technological and biological activities. The RSM assisted optimization resulted in maximum production of EPS (12.58 g/L) when the MRS broth was supplemented with optimal carbon and...

Aim: The present study aims to evaluate the potential antioxidant and antiproliferative properties of probiotic bacterial isolates Weissella cibaria p3B, Bacillus subtilis CS, and Bacillus tequilensis CL, isolated from South Indian fermented tomato pickle (homemade) and gut content of indigenous country chicken. Methods and results: The bacteria...

The taxonomic status of the large-sized Fejervarya frogs of the Andaman and Nicobar Islands was assessed based on integrative analysis of molecular, morphological and acoustic data. Our results identify the population from the Andaman Islands as Fejervarya moodiei, and that from the Nicobar Islands as F. limnocharis. Representative specimens collec...

Biosurfactant-producing bacteria were isolated from transformer oil-contaminated soil. The strain was identified as Pseudomonas aeruginosa PU1 based on its molecular characterization by 16S rRNA gene sequencing. The extraction of biosurfactant was done by acid precipitation method using 2 N hydrochloric acid and further purified by silica-gel colum...

This study was conducted to evaluate the probiotic potential of Weissella confusa MD1 and Weissella cibaria MD2 isolated from a fermented batter. They possessed characters like high survivability in gastrointestinal conditions, tolerance towards lysozyme and phenol. Both strains exhibited strong auto-aggregation property and co-aggregation with Lis...

The present study focused on production, optimization and characterization of exopolysaccharide (EPS) from Weissella confusa MD1. The purified EPS MD1 was also evaluated for in vitro biological activities. The maximum yield of EPS (10.07 ± 0.32 g/L) was obtained with optimized culture conditions of 35 ˚C at pH 6.5 for 36 h with 4% (w/v) galactose a...

Analysis of mitochondrial 16s rDNA data from a nearly topotypical specimen of the common Indian cricket frog (Minervarya agricola) sequenced during this study revealed a potential conspecificity among samples of Minervarya originating from different parts of the Indian subcontinent including Nepal, Bangladesh, Sri Lanka and the Western Ghats. As th...

The potent antioxidant probiotic strains Lactobacillus mucosae AN1 and Lactobacillus fermentum SNR1 were assessed for anti-inflammatory properties in carrageenan (acute) and complete Freund’s adjuvant-induced inflammation (chronic) models in the present study. The two probiotic strains were administered orally along with feed to the Wistar albino m...

Lactobacillus mucosae strain AN1 isolated from sheep milk and characterized for its probiotic suitability. In vitro evaluation of critical gut endurance properties of this strain were assessed by different screening methods such as bile salt, gastric acid, lysozyme tolerance assays, hemolytic, cholesterol reduction properties, and HT-29 cell line a...

OBJECTIVES The present study aims to investigate the anti-oxidant and anti-inflammatory properties of seagrass Halophila ovalis sulfated polysaccharide on HT-29 cell line. SUBJECTS AND METHODS Monosaccharides composition was identified using liquid chromatography-mass spectrometry (LC-MS) and the functional groups were analyzed using Fourier trans...

In this present study, a gene (ent-B) encoding the bacteriocin enterocin-B was cloned, overexpressed and purified from Enterococcus faecium por1. The molecular weight of the bacteriocin enterocin-B was observed around 7.2 kDa and exhibited antimicrobial activity against several human pathogenic bacteria. The antimicrobial activity of cloned enteroc...

A gene coding lipase from Bacillus sp. PU1 was cloned and expressed in E. coli BL21(DE3) pLysS. The purified lipase has a molecular weight of 23 kDa, is highly alkaline (pH range 8-10) and mesophilic (20–50 °C). Three dimensional structure of the lipase was modeled by comparative homology and identified as a typical serine lipase by the presence of...

A vancomycin susceptible Enterococus faecalis CV7 produced bacteriocin was purified by size exclusion chromatography followed by RP-HPLC C-18 column. Tricine-SDS PAGE unrevealed molecular mass was further confirmed by MALDI-TOF MS as 4.829 kDa. This bacteriocin showed broad spectrum of anti-bacterial activity against important food borne pathogens...

Aim The aim of this objective is to evaluate the antinociceptive and anti-inflammatory potential of sulfated polysaccharide purified fractions isolated from brown seaweed Sargassum wightii and seagrass Halophila ovalis in male Wistar rats. Subjects and Methods Crude sulfated polysaccharide from S. wightii and H. ovalis was subjected to anion excha...

Duck intestinal homogenate isolate Enterococcus faecalis DU10 produced exopolysaccharide (EPS) (840 mg/L) in MRS medium (35 °C, pH 6.5), was characterized for its physicochemical, biosorption, antioxidant, antibiofilm and rheological properties. HPTLC analysis revealed fructose and arabinose are as major, xylose and mannose are as minor constituent...

Goat milk isolate Lactobacillus sakei GM3 exhibited acid and bile tolerance and showed antagonistic activity against food borne pathogens. Bacteriocin produced by L. sakei GM3 reached maximum production at stationary phase after 18 h. Bacteriocin was found to be retained active after treatment with different pH, temperature and organic solvents but...

A protease gene of Bacillus cereus PMW8 isolated from a cow milk sample was cloned in E. coli DH5α. Sequence analysis confirmed 1700 bp of protease gene and further expression was carried out using E. coli BL21(DE3)PLysS cells. The optimum conditions for expression were noted as 0.1 mM IPTG for 3 h at 37 °C, whereupon the resultant protease was obs...

A novel bacteriocin produced by avian duck isolated lactic acid bacterium (LAB), Enterococcus faecalis DU10 was isolated. This bacteriocin showed broad spectrum of antibacterial activity against important food borne pathogens and purified by size exclusion chromatography followed by RP-HPLC C-18 column. Tricine-SDS PAGE revealed the presence of a b...

Lactobacillus plantarum is among the most prominent lactic acid bacterium (LAB), which has one of the largest genomes of LAB [1]. Due to this, it can express various genes that provide this species with a high ability to customized to varying external conditions, and also it can attach to different substrates [2]. Lb. plantarum has been isolated fr...

The aim of this study was the partial characterization of plantaricin MZ, a two-component antimicrobial peptides produced by the putative probiotic bacteria Lactobacillus plantarum DU10, which was isolated from Algerian raw camel milk. This biomolecule was secreted in the supernatant of a L. plantarum DU10 culture and showed diverse spectrum of ant...

The aim of this study was the partial characterization of plantaricin MZ, a two-component antimicrobial peptides produced by the putative probiotic bacteria Lactobacillus plantarum DU10, which was isolated from Algerian raw camel milk. This biomolecule was secreted in the supernatant of a L. plantarum DU10 culture and showed diverse spectrum of ant...

Lactic acid bacteria have long been considered safe and suitable for human consumption when administered in adequate amounts. The aim of this study is to investigate the probiotic properties of Lactobacillus plantarum DU10 isolated from Algerian raw camel milk. The analysis of haemolytic and gelatinase activity, bile tolerance, cholesterol lowering...

The objective of this study was to evaluate the effect of dietary and water supplementation of probiotic Streptococcus phocae PI80 on growth, immune response and feed utilization of tiger shrimp Penaeus monodon in earthen ponds. The probiotic bacterium S. phocae PI80 was cultured in large fermenter (50 L) by adding additional carbon source in the f...

Abstract The present study investigated the effects of sulfated polysaccharides from brown seaweed Sargassum wightii (Sw-SP) and seagrass Halophila ovalis (Ho-SP) in nociceptive and inflammatory models. In the formalin test, Sw-SP and Ho-SP significantly reduced licking time in both phases of the test at a dose of 10 mg/kg. In the hot plate test, t...

During the past two decades probiotic bacteria have been increasingly proposed as health promoting bacteria in variety of food system, because of its safety, functional, and technological characteristics. Commonly, Lactobacillus spp., Bifidobacterium spp., Saccharomyces boulardii, and some other microorganisms have been considered as probiotic stra...

The synthesis and functional characterization of an antibiofilm exopolysaccharide (EPS) from a probiotic Enterococcus faecium MC13 were investigated. The temperature of 35 °C, pH of 6.5, and salinity of 1-2 % were found to be optimum for EPS production. The sucrose (30 g l(-1)) and yeast extract (20 g l(-1)) acted as suitable carbon and nitrogen so...

The aim of the study was to establish the immune response induced by Streptococcus phocae PI80, Bacillus subtilis, and commercial probiotics (Uni-Ecosense, EcoForce, Uni-Hatch) in the shrimp, Penaeus monodon. Total hemocyte count, phenoloxidase activity, nitroblue tetrazolium (NBT) reductase assay, phagocytic activity, and disease resistance was ev...

This review describes the diversity of Indian fermented food and its significance as a potential source of lactic acid bacteria (LAB). Fermented foods consumed in India are categorized based upon their base material. Fermented foods such as dahi, gundruk, sinki, iniziangsang, iromba, fermented rai, kanjika and handua were reported to have significa...

The effects of protective culture Enterococcus faecium MC-13 on the shelf life of beheaded, scaled and gutted oil sardines (Sardinella longiceps) and tiger shrimp (Penaeus monodon) during refrigerated storage were examined. The control and the treated samples were analyzed periodically for chemical (PV, TVB-N), microbiological (total viable count),...

The present study was carried out to evaluate the efficiency of gamma radiation (1–10 kGy) in combination with antioxidant wrapping (butylated hydroxyanisole [BHA], curcumin, ethylenediaminetetraacetic acid [EDTA]) for extending the quality and shelf life of goat fish Parupeneus indicus Quality assessment was studied by monitoring the chemical (tot...

The relationship between antioxidant and anticancer properties of probiotic bacterium strain Lactobacillus plantarum AS1 (AS1) in colon cancer induced by 1,2-dimethylhydrazine (DMH) has been studied. In this study, an increased level of lipid peroxide (LPO) products and increased activities of antioxidant enzymes (superoxide dismutase, catalase and...

The aim of this work was to investigate the effect of cryoprotectants on the survival of probiotic bacterium Enterococcus faecium MC13 during freeze drying and storage. The maximum relative cell viabilities were observed when cells were freeze dried and stored at −20 °C, which is optimum temperature for the preservation of E. faecium. At all storag...

The aim of the present study was to focus on the impact of two different methods and the effects of cryoprotectants on the survival of a probiotic bacterium, Streptococcus phocae PI80, during storage. For the protection of freeze dried cells, the optimal storage conditions were determined with a high survival rate. After the freeze drying process,...

Halophila spp. is a strong medicine against malaria and skin diseases and is found to be very effective in early stages of leprosy. Seagrasses are nutraceutical in nature and therefore of importance as food supplements. The antibacterial, antioxidant, and anti-inflammatory activities of Halophila ovalis R. Br. Hooke (Hydrocharitaceae) methanol extr...

A bacteriocin producer strain MC13 was isolated from the gut of Mugil cephalus (grey mullet) and identified as Enterococcus faecium. The bacteriocin of E. faecium MC13 was purified to homogeneity, as confirmed by Tricine sodium dodecyl sulphate – polyacrylamide gel electrophoresis (SDS–PAGE). Reverse-phase high-performance liquid chromatography (HP...

In this study, a statistics-based experimental design was utilised for the optimisation of a growth medium which possibly enhanced bacteriocin production by Streptococcus phocae PI80. Carbon, nitrogen sources and a bio-surfactant were first screened using a one variable at a time technique and scored for increasing yield production. The selected va...

The present study involved the control of Aeromonas hydrophila in Cyprinus carpio by bacteria Enterococcus faecium MC13 isolated from fish Mugil cephalus intestine. Antagonistic effects were confirmed against Aeromonas hydrophila by cross-streaking and the agar spot method. Probiotic effects of the isolate were confirmed by injection and oral admin...

Lactobacillus plantarum AS1 was incubated with HT-29 adenocarcinoma cell line to assess its adhesion potency and examined for its inhibitory effect on the cell attachment by an enterovirulent bacterium Vibrio parahaemolyticus. Lactobacillus plantarum AS1 attached efficiently to HT-29 cells as revealed by scanning electron microscopy and bacterial a...

The quenching capacities of Vitus vinifera seed extract, Citrus limon peel extract, Punica granatum peel extract, and Citrus sinensis peel extract were studied together with their antioxidant activity in goat fish (Parupenaeus indicus). The functionality of the extracts was evaluated using β-carotene-linoleic acid model system, reducing power assay...

The influence of Streptococcus phocae PI80 on the shelf life of Sardinella longiceps and Penaeus monodon was investigated by measurement of microbial and chemical analysis after appraising the safety of the protective probiotic culture in wistar rat’s model. The results of this safety assessment indicate that oral administration of protective cultu...

The standard MRS components were optimized using response surface methodology for increasing yield of Streptococcus phocae PI80 viable cells and its bacteriocin. The highest amounts of bacteriocin activity and viable cells were recorded from prediction point of optimized MRS medium and achieved two fold higher (33049.8 AU.mL-1 and 14.05 LogCFU.mL-1...

The standard MRS components were optimized using response surface methodology for increasing yield of Streptococcus phocae PI80 viable cells and its bacteriocin. The highest amounts of bacteriocin activity and viable cells were recorded from prediction point of optimized MRS medium and achieved two fold higher (33049.8 AU.mL(-1) and 14.05 LogCFU.mL...

The aim of this study was to optimize medium composition for higher yield of total viable cells and bacteriocin by Enterococcus faecium MC13. The factors such as peptone, meat extract, yeast extract, lactose, glycerol, tween 80, triammonium citrate and K2HPO4 were selected based on the Lactobacillus MRS medium composition. Two level factorial desig...

The antibacterial effect of the crude methanol extracts and purified fractions of Cladophora glomerata (Linnaeus) Kützing (Cladophoraceae) against multidrug resistant human pathogen Acinetobacter baumannii and fish pathogens were investigated. Cladophora glomerata demonstrated appreciable activity against the human pathogen A. baumannii and fish pa...

Statistics-based experimental designs were used to develop a cost-effective medium for enhanced production of viable cells and bacteriocin by probiotic Enterococcus faecium MC13. Carbon, nitrogen, and mineral sources were first screened by one-variable-at-a-time (OVAT) methods. In order to increase yield production, the selected variables were furt...

Twenty-five strains of lactic acid bacteria (LAB) isolated from South Indian traditional fermented foods Kallappam batter, Koozh and Mor Kuzhambu. Further 6 strains were selected based on their antimicrobial activity. They were identified according to morphological, biochemical and physiological criteria. Identification by 16S rDNA sequence homolog...

The strain PI80 which showed promising antimicrobial effect on different shrimp and fish pathogens was isolated from gut of shrimp Penaeus indicus. Based on 16Sr RNA gene sequence similarities and phenotypic characterization, strain PI80 was identified as a member of the genus Streptococcus. The G+C content of the partial DNA sequence was 53 %. Str...

Problem statement: The present work was attempted to evaluate the probiotic activity of Bacillus spp. in shrimp health management. Approach: Penaeid culture ecosystem as a confined environment with huge inputs always encourages the proliferation of pathogenic bacteria like Vibrios. Results: From the present study and earlier reports it is understoo...

The solid state fermentation is one of the most economically viable processes for the bioconversion of lignocellulosic coir waste is represented by Phanerochaete chrysosporium and Rhizopus stolonifer. Coir pith is a waste lignocellusic material; it consists of lignin, cellulose, hemicellulose and protein. The two fungal cultures are able to synthes...

A bacteriocin-producing strain PI80 was isolated from the gut of Penaeus indicus (Indian white shrimp) and identified as Streptococcus phocae PI80. The bacteriocin was purified from a culture supernatant to homogeneity as confirmed by Tricine SDS-PAGE. Reverse-phase HPLC analysis revealed a single active fraction eluted at 12.94 min, and MALDI-TOF...

The effects of dietary β- (1,3) glucan and whole cell yeast (Sacharomyces uvarum) on the immune response and disease resistance to Aeromonas hydrophila were investigated in Cyprinus carpio. β-(1,3) glucan was extracted from the yeast. Both β-(1,3) glucan and whole yeast were incorporated into the diet at 1% level and fed to common carp C. carpio fo...

Occurrence of widespread epizootics among larval and cultured shrimp has put on viable preventive approaches such as application of probiotics on a high priority in aquaculture. In the present study, four probiotics bacteria were isolated from marine fish and shrimp intestine based on the antagonistic activity and nonpathogenic to the host. The iso...

Newly hatched Channa striatus (Bloch) were tested for survival and growth under various delayed feeding regimes. Channa striatus larvae were found to be extremely tolerant to the delay in initial feeding. About 9% of the larvae died when initial feeding was delayed by 2 days after yolk absorption. However, mortality progressively increased with fur...

To determine the effect of chitin, chitosan and levamisole on the immune response and growth of common carp (Cyprinus carpio) under field conditions, fish were fed with these compounds for a period of 90 days and then challenged with Aeromonas hydrophila. Dietary supplementation of chitosan, levamisole and chitin enhanced the growth of all treated...

1.1.|Embryonic development of Channa striatus lasted or 56, 48, 36 and 30 h at 20, 24, 28 and 32°C, respectively.2.2.|Larvae reared at 32°C utilized the adhering yold much faster (102 h) than those reared at 20°C (156 h).3.3.|No significant differences were found in total body length and water content.4.4.|However, the ash content and ash free dry...

Channa striatus larvae were extremely tolerant to a delay in initial feeding. About 9% of the larvae died when initial feeding was delayed by 2 days after yolk absorption, but mortality progressively increased with further delays in first feeding. Only 26% of larvae took food when it was offered 11 days after yolk absorption. "Point of no return' w...

Juveniles ofChanna striatus were fed twice a week with hormone supplemented diet at concentrations of 0, 1, 2·5, or 10 mg/kg fish and the hormone effects on growth and food utilization were observed for a period of 75 days. Neither ethylestrenol nor the tested doses of the steroid appear to significantly change feeding rate. Administration of 5 mg...

The effects of carbaryl (1-naphthalenyl methylcarbamate), an extensively used insecticide in agricultural operations, have been studied on survival, growth, and metamorphosis of the bullfrog tadpoleRana tigrina. The 96 hr LC50 value for tadpoles (0.02 g) was 6.2 mg/L. The tadpoles were reared from hatching to metamorphosis in sublethal concentratio...