Antibiofilm and antivirulence activity of selenium nanoparticles synthesized from cell-free extract of moderately halophilic bacteria.

Biofilm-forming microbes can pose a major health risk that is difficult to combat. Nanotechnology, on the other hand, represents a novel technique for combating and eliminating biofilm-forming microbes. In this study, the selenium nanoparticles (SeNPs) were biosynthesized from moderate halophilic bacteria isolated from Pichavaram mangrove sediments. The bacterial strain S8 was found to be efficient for SeNPs synthesis and hence identified by 16s r RNA sequencing as Shewanella sp. In UV- spectral analysis the SeNPs displayed a peak at 320 nm due to surface plasmon resonance (SPR). The cell-free extract of Shewanella sp. and SeNPs indicates that the various functional groups in the cell-free extract were mainly involved in the synthesis and stabilization of SeNPs. The SeNPs had a spherical form with average diameter of 49 ± 0.01 nm, according to the FESEM analysis. The EDX shows the distinctive peaks of selenium at 1.37, 11.22.12.49 Kev. In the agar well diffusion method, the SeNPs show inhibitory activity against all the test pathogens with the highest activity noted against P.aeruginosa with a zone of inhibition of 22.7 ± 0.3 mm. The minimal inhibitory concentration (MIC) value of 80 µg/ml, minimal bactericidal concentration (MBC) of 160 µg/ml, and susceptibility constant of 0.043 µg/ml show that SeNPs highly effective against P.aeruginosa. The Sub-MIC value of SeNPs of 20 µg/ml was found to inhibit P.aeruginosa biofilm by 85% as compared to the control. Further, the anti-virulence properties viz., pyocyanin, pyoverdine, hemolytic, and protease inhibition revealed the synthesized SeNPs from halophilic bacteria control the pathogenicity of P.aeruginosa.

Characterization and antibacterial evaluation of Eco-friendly silver nanoparticles synthesized by halophilic Streptomyces rochei SSCM102 isolated from mangrove sediment.

BACKGROUND: Antimicrobial resistance has surged due to widespread antimicrobial drug use, prompting interest in biosynthesizing nanoparticles from marine-derived actinomycetes extracellular metabolites, valued for their diverse bioactive compounds. This approach holds promise for addressing the urgent need for novel antimicrobial agents. The current study aimed to characterize novel bioactive compounds from unexplored biodiversity hotspots, halophilic Streptomyces sp. isolated from mangrove sediment in the Pichavaram region, India. METHODS AND RESULTS: Streptomyces rochei SSCM102 was conclusively identified through morphological and molecular characterization. Synthesis of silver nanoparticles (AgNPs) from Streptomyces rochei SSCM102 was characterized using various techniques, including UV-Vis, XRD, SEM, EDX, and FT-IR. The UV-Vis spectrum of the reduced AgNPs exhibited a prominent peak at 380 nm, confirming the AgNPs. The UV-Vis spectrum confirmed the synthesis of AgNP, and SEM analysis revealed a cubic morphology with sizes ranging from 11 to 21 nm. The FTIR spectrum demonstrated a shift in frequency widths between 626 cm-1 and 3432 cm-1. The EDX analysis substantiated the presence of metallic silver, evident from a strong band at 1.44 keV. The synthesized AgNPs exhibited antibacterial efficacy against human pathogens Escherichia coli (64 ± 0.32 µg/ml), Klebsiella pneumoniae (32 ± 0.16 µg/ml), and Pseudomonas aeruginosa (16 ± 0.08 µg/ml) by MIC and MBC values of 128 ± 0.64 (µg/ml), 64 ± 0.32 (µg/ml) and 32 ± 0.16 (µg/ml), respectively. Additionally, at a concentration of 400 µg/ml, the AgNPs displayed a 72% inhibition of DPPH radicals, indicating notable antioxidant capacity. The LC50 value of 130 µg/mL indicates that the green-synthesized AgNPs have lower toxicity by Brine Shrimp Larvae assay. CONCLUSION: The study's novel approach to synthesizing eco-friendly silver nanoparticles using Halophilic Streptomyces rochei SSCM102 contributes significantly to the field of biomedical research and drug development. By demonstrating potent antibacterial properties and aligning with sustainability goals, these nanoparticles offer promising avenues for novel antibacterial therapies.

Baseline assessment of marine actinobacterial diversity around the nuclear power plant sites, India and its application to uranium remediation.

Baseline assessments of marine microbial studies are very limited around ecologically sensitive areas of the Nuclear Power Plant (NPP) site with respect to their occurrence, distribution, role in adaptation, and their potential remediation process. The distribution and diversity of marine microbes are largely dependent on the physicochemical parameters relating to a specific area, especially spore-producing marine actinobacteria are a source for indigenous bioremediation agents. Marine actinobacterial diversity with conventional and 16 S rRNA gene analysis was done with different pre-treatment conditions and selective media. Totally, 170 different strains are identified in genera level and it belongs to 18 genera with dominant by Streptomyces sp. (75species) followed by Nocardiposis sp, (18species) Rhodococcus sp. (14species). Multiple k-dominance plots simplified the perception of marine actinobacteria according to genera level influence to standard stock. This is the first kind of study in India and the results could act as baseline inventory in terms of microbial diversity around NPP sites. Further, a potential strain of Actinomadura sp. (T5S13) produced 243.7 mg/L of EPS and remediate the Uranium radionuclides. The functional group shifting and adsorption nature were also confirmed by SEM with EDS analysis.

General Dentist's Knowledge and Attitude Towards Non-Surgical Endodontic Retreatment in Tunisia: A Cross-Sectional Study.

Introduction: Root canal retreatment is carried out in cases where previous endodontic therapies failed and involves the removal of root canal filling materials, followed by cleaning, shaping, and obturating of the canals. Aims: : The objective of this study was to collect information regarding attitudes, methods, and materials employed during the non-surgical endodontic retreatment (NSER) by general dentists working in Sousse Governorate, Tunisia. Materials and Methods: A descriptive cross-sectional survey was conducted among 147 general dentists working in the Sousse Governorate, Tunisia, from May to November 2021. Data were collected by sending a structured questionnaire to the dental practitioners through email. All the data were analyzed by using the SPSS 10 computer software. Results: A total of 96 dentists responded to this survey. The response rate was 63.5%, with a female predominance (53.2.3%). 81.2% of the respondents performed at least one non-surgical endodontic retreatment (NSER) weekly. Our study revealed that the mandibular first molar is the tooth that most often requires endodontic retreatment (83.5%). Half of the participants never used the rubber dam during this procedure. Moreover, the majority of respondents (61.9%) simultaneously used manual files and rotary nickel-titanium instruments for root canal desobturation. Most of the dentists (69.57%) systematically use solvents during root canal desobturation. Conclusion: Our survey highlights that the majority of general dentists have adequate knowledge about endodontic retreatment. Nevertheless, dentists are yet to start the application of these newer strategies towards the management of endodontic failures.

Fabrication of Curcumin-Based Electrochemical Nanosensors for the Detection of Environmental Pollutants: 1,4-Dioxane and Hydrazine.

This work reports the development of novel curcuminoid-based electrochemical sensors for the detection of environmental pollutants from water. In this study, the first set of electrochemical experiments was carried out using curcumin-conjugated multi-walled carbon nanotubes (MWCNT-CM) for 1,4-dioxane detection. The MWCNT-CM/GCE showed good sensitivity (103.25 nA nM-1 cm-2 in the linear range 1 nM to 1 µM), with LOD of 35.71 pM and LOQ of 108.21 pM. The second set of electrochemical experiments was carried out with bisdemethoxy curcumin analog quantum dots (BDMCAQD) for hydrazine detection. The BDMCAQD/GCE exhibited good sensitivity (74.96 nA nM-1 cm-2 in the linear range 100 nM to 1 µM), with LOD of 10 nM and LOQ of 44.93 nM. Thus, this work will serve as a reference for the fabrication of metal-free electrochemical sensors using curcuminoids as the redox mediator for the enhanced detection of environmental pollutants.

In-vivo anti-hyperglycemic effect of herbal extracts Tribulus terrestris (L) and Curcuma amada (R) on streptozotocin-induced diabetic rats and its associated histopathological studies.

Dia/betes is a serious health concern in many countries with high blood glucose, obesity, and multiple organ failures in late stages. Treating diabetes with effective drugs is still a challenging issue since most of the available diabetic drugs are not effective in combating diabetes, especially in secondary disease complications like obesity, retinopathy, and nephropathy associated with diabetes. Hence search for effective antidiabetic medication, especially from natural sources is mandatory with no adverse side effects. In the present study, a combined herbal aqueous extract of Tribulus terrestris and Curcuma amada was administered to diabetic-induced rats for 37 days. During experimentation, the mean blood glucose level was estimated and at the end of the experiment on the 37th day, the animal was sacrificed and observed for weight gain, plasma insulin, glycogen, glycated hemoglobin, urea, and creatinine level. The results revealed that TT and CA extract-treated diabetic groups significantly lowered the mean blood glucose level followed by increased glycogen and insulin level. Urea, creatinine, and HbA1c levels were considerably reduced in TT and CA-treated diabetic animals as compared to that of antidiabetic drug Glibenclamide-treated groups. TT and CA-treated diabetic animals showed considerable net body weight gain at the end of the experimental day. A concluding remark of the study shows that TT and CA herbal extract is effective against diabetes and it can be considered as an antidiabetic agent in ayurvedic medicine practice.

Isolation of anticancer bioactive secondary metabolites from the sponge-derived endophytic fungi Penicillium sp. and in-silico computational docking approach.

Introduction: Fungus-derived secondary metabolites are fascinating with biomedical potential and chemical diversity. Mining endophytic fungi for drug candidates is an ongoing process in the field of drug discovery and medicinal chemistry. Endophytic fungal symbionts from terrestrial plants, marine flora, and fauna tend to produce interesting types of secondary metabolites with biomedical importance of anticancer, antiviral, and anti-tuberculosis properties. Methods: An organic ethyl acetate extract of Penicillium verruculosum sponge-derived endophytic fungi from Spongia officinalis yielded seven different secondary metabolites which are purified through HPLC. The isolated compounds are of averufin (1), aspergilol-A (2), sulochrin (3), monomethyl sulochrin (4), methyl emodin (5), citreorosein (6), and diorcinol (7). All the seven isolated compounds were characterized by high-resolution NMR spectral studies. All isolated compounds', such as anticancer, antimicrobial, anti-tuberculosis, and antiviral, were subjected to bioactivity screening. Results: Out of seven tested compounds, compound (1) exhibits strong anticancer activity toward myeloid leukemia. HL60 cell lines have an IC50 concentration of 1.00µm, which is nearly significant to that of the standard anticancer drug taxol. A virtual computational molecular docking approach of averufin with HL60 antigens revealed that averufin binds strongly with the protein target alpha, beta-tubulin (1JFF), with a -10.98 binding score. Consecutive OSIRIS and Lipinski ADME pharmacokinetic validation of averufin with HL60 antigens revealed that averufin has good pharmacokinetic properties such as drug score, solubility, and mutagenic nature. Furthermore, aspergilol-A (2) is the first report on the Penicillium verruculosum fungal strain. Discussion: We concluded that averufin (1) isolated from Penicillium verruculosum can be taken for further preliminary clinical trials like animal model in-vivo studies and pharmacodynamic studies. A future prospect of in-vivo anticancer screening of averufin can be validated through the present experimental findings.

Biological Activity of Cyclic Peptide Extracted from Sphaeranthus amaranthoides Using De Novo Sequencing Strategy by Mass Spectrometry for Cancer.

Though there are several advancements and developments in cancer therapy, the treatment remains challenging. In recent years, the antimicrobial peptides (AMPs) from traditional herbs are focused for identifying and developing potential anticancer molecules. In this study, AMPs are identified from Sphaeranthus amaranthoides, a natural medicinal herb widely used as a crucial immune stimulant in Indian medicine. A total of 86 peptide traces were identified using liquid-chromatography-electrospray-ionisation mass spectrometry (LC-ESI-MS). Among them, three peptides were sequenced using the manual de novo sequencing technique. The in-silico prediction revealed that SA923 is a cyclic peptide with C-N terminal interaction of the carbon atom of ASP7 with the nitrogen atom of GLU1 (1ELVFYRD7). Thus, SA923 is presented under the orbitides class of peptides, which lack the disulfide bonds for cyclization. In addition, SA923, steered with the physicochemical properties and support vector machine (SVM) algorithm mentioned for the segment, has the highest in silico anticancer potential. Further, the in vitro cytotoxicity assay revealed the peptide has anti-proliferative activity, and toxicity studies were demonstrated in Danio rerio (zebrafish) embryos.

Cardiovascular diseases prediction by machine learning incorporation with deep learning.

It is yet unknown what causes cardiovascular disease (CVD), but we do know that it is associated with a high risk of death, as well as severe morbidity and disability. There is an urgent need for AI-based technologies that are able to promptly and reliably predict the future outcomes of individuals who have cardiovascular disease. The Internet of Things (IoT) is serving as a driving force behind the development of CVD prediction. In order to analyse and make predictions based on the data that IoT devices receive, machine learning (ML) is used. Traditional machine learning algorithms are unable to take differences in the data into account and have a low level of accuracy in their model predictions. This research presents a collection of machine learning models that can be used to address this problem. These models take into account the data observation mechanisms and training procedures of a number of different algorithms. In order to verify the efficacy of our strategy, we combined the Heart Dataset with other classification models. The proposed method provides nearly 96 percent of accuracy result than other existing methods and the complete analysis over several metrics has been analysed and provided. Research in the field of deep learning will benefit from additional data from a large number of medical institutions, which may be used for the development of artificial neural network structures.

Feasibility study on intact human umbilical cord Wharton's jelly as a scaffold for human autologous chondrocyte: In-vitro study.

OBJECTIVES: Placental tissue is an established biomaterial used in many clinical applications. However, its use for tissue engineering purposes has not been fully realized. Though articular cartilage extracellular matrix (ECM)-derived oriented scaffolds for cartilage tissue engineering were developed, resources are a hindrance to its application. In this regard, the present study investigated the feasibility of using intact decellularized human umbilical cord Wharton's jelly (hUC-WJ) as a new material for chondrocyte carrier in cartilage tissue engineering. The developed hUC-WJ scaffold provides a good microenvironment for the attachment, viability, and delivery of seeded human autologous chondrocytes. It has an advantage over other biomaterials in terms of abundant availability and similar biochemistry to cartilage ECM. MATERIALS AND METHODS: hUC-WJ obtained from fresh human placenta were decellularized and gamma sterilized. Human cartilage tissue was obtained from the patients with a total knee replacement. The chondrocytes were isolated and expanded in-vitro and seeded onto the hUC-WJ scaffold. The efficiency of the decellularized tissue as a delivery system for human cartilage cells was investigated by histology, immunohistochemistry, cell count, flow cytometry, and scanning electron microscopy (SEM). RESULTS: The results showed that the decellularized hUC-WJ scaffold has supported the microenvironment for chondrocyte attachment and viability without losing its phenotype. In addition, the cells were spread through the hUC-WJ scaffold as confirmed by histology and SEM. CONCLUSION: Based on obtained results, the hUC-WJ scaffold has great potential as a 3D scaffold for human autologous chondrocyte carriers in tissue engineering and regenerative medicine applications.

Reduction of environmental chemicals, toxicity and particulate matter in wet scrubber device to achieve zero emissions.

The fine particles generated by the foundry industry are present in the atmosphere; they have an impact on the climate because of their influence on atmospheric radioactive phenomena. As a result of this scenario, there is a rising amount of legislation restricting the emission of pollutants from foundry industries and related businesses. In response to this situation, many researchers have concentrated on end-of-pipe technologies, one of which is the wet scrubber, which is a device that is primarily used in foundries to control pollution and is one of the devices that has been incorporated. The disadvantage of using this wet scrubber, on the other hand, is that it contributes to secondary pollution when it is used. In order to combat secondary pollution, a model of an enhanced wet scrubber system that incorporates a multi-sand filtering technology was developed. The performance of this redesigned wet scrubber system was evaluated with the use of computational fluid dynamics (CFD) software. In CFD, the Reynolds stress model was applied for simulation. The pressure magnitudes and velocity magnitudes are obtained by this simulation. The volume fraction of the dust was evaluated through the DPM approach. Because of the introduction of the filtration tank's computation, it was discovered that successful filtration was accomplished using sand filters, meaning that environmental chemicals and particles were totally filtered from 0.17 kg at the entrance to zero kg of particles at the outflow.

Investigation on Pollution Control Device (PCD) in iron foundry industry to reduce environmental chemicals.

Right from the olden days, many products have been made according to foundry practices in order to generate prosperity in the societies in which they operate while reaping these types of benefits through the operation of foundries. It is alarming that the emissions released by foundries affect human health. Therefore, foundries installed Pollution Control devices (PCDs), in accordance with this development; researchers examined the effectiveness of these PCDs in controlling emissions from foundries in different parts of the world. The emission control obtained by installing these PCDs is explained in this article based on the data gathered from the survey. The cartridge filter equipped with an induction furnace reduced the concentration of SPM to less than 20 mg/Nm3. This result of the investigation indicates that the cartridge filter built into the induction furnace achieves the best efficiency in controlling contaminants from iron foundries. Interestingly, the operation of the cartridge filter has yet to be documented. Therefore, the construction operation, the performance of the cartridge filter, and its efficiency in achieving contaminations control in foundries are described. This will provide useful information on the use of cartridge filters in an induction furnace to reduce Iron foundry emissions.

Targeting Streptomyces-Derived Streptenol Derivatives against Gynecological Cancer Target PIK3CA: An In Silico Approach.

Streptomyces is amongst the most amenable genera for biotechnological applications, and it is extensively used as a scaffold for drug development. One of the most effective therapeutic applications in the treatment of cancer is targeted therapy. Small molecule therapy is one of them, and it has gotten a lot of attention recently. Streptomyces derived compounds namely streptenols A, C, and F-I and streptazolin were subjected for ADMET property assessment. Our computational studies based on molecular docking effectively displayed the synergistic effect of streptomyces-derived compounds on the gynecological cancer target PIK3CA. These compounds were observed with the highest docking scores as well as promising intermolecular interaction stability throughout the molecular dynamic simulation. Molecular docking and molecular dynamic modeling techniques were utilized to investigate the binding mode stability of drugs using a pharmacophore scaffold, as well as physicochemical and pharmacokinetic aspects linked to alpelisib. With a root mean square fluctuation of the protein backbone of less than 0.7 nm, they demonstrated a steady binding mode in the target binding pocket. They have also prompted hydrogen bonding throughout the simulations, implying that the chemicals have firmly occupied the active site. A comprehensive study showed that streptenol D, streptenol E, streptenol C, streptenol G, streptenol F, and streptenol B can be considered as lead compounds for PIK3CA-based inhibitor design. To warrant the treatment efficacy against cancer, comprehensive computational research based on proposed chemicals must be assessed through in vitro studies.

Silver nanoparticles synthesized from the seaweed Sargassum polycystum and screening for their biological potential.

World-wide antimicrobial resistant is biggest threat in global health. It requires the urgent need of multisectoral action for the scientific community to achieve the sustainable development Goals. Due to their antimicrobial properties, silver nanoparticles are potential activates to pathogens, which explains their potential for multiple applications in various fields. In the present studies, we evaluate the antimicrobial properties of a Sargassum polycystum algal extract, an unrivaled green synthetic method for producing -defined shaped seaweed silver nanoparticles. To confirm their structure and size, some characterization techniques are used, such as Absorption spectrophotometer (UV-VIS), Fourier transforms infrared spectroscopy (FTIR), Scanning electron Microscope (SEM), Transmission electron microscopy (TEM) and X-Ray diffraction (XRD). Evaluate the antibacterial and anti-mycobacterial activity using silver nanoparticles. The toxicity study of this silver nanoparticle has been done with the help of zebrafish larva. The biological nanoparticle having good antimicrobial activity against Staphylococcus aureus, Micrococcus luteus, Pseudomonas fluorescens and Candida albicans and also it shows potent activity against MTB H37Rv, SHRE sensitive MTB Rifampicin resistant MTB around 98%. Seaweed nanoparticles had lower toxicity for the survival of the fish larvae. In comparison, other dosages will arrest the cell cycle and leads to death. The present finding revealed that these seaweeds nanoparticles have potential anti-mycobacterial activity against pathogens at low concentrations. This makes them a potent source of antibacterial and anti-TB agents.

Isolongifolene-loaded chitosan nanoparticles synthesis and characterization for cancer treatment.

Recent breakthroughs in the field of nanoparticle-based therapeutic delivery methods have changed the standpoint of cancer therapy by effectively delaying the process of disease development. Nanoparticles have a unique capacity of good penetrating ability than other therapeutic leads used in traditional therapeutics, and also, they have the highest impact on disease management. In the current study isolongifolene-loaded Chitosan nanoparticles have been formulated, synthesized and then characterized by the use of Fourier Transform Infrared Spectroscopy, X-ray Diffraction, Scanning Electron Microscopy and Transmission Electron Microscopy. Further, the characterized chitosan nano formulation was evaluated for hemocompatibility, plasma stability, and in-vitro release. Isolongifolene-loaded chitosan nanoparticles were found to be compatible with plasma and also, they exhibited a constant release pattern. Hence, chitosan-loaded nanoparticles could be employed as an excellent adjuvant in cancer therapeutic, to combat the multi-drug resistance in solid tumors.

Preparation of an Intelligent pH Film Based on Biodegradable Polymers for Monitoring the Food Quality and Reducing the Microbial Contaminants.

Hydrogel refers to a three-dimensional cross-linked polymeric network made of synthetic or natural polymers that can hold water in its porous structure. The inclusion of hydrophilic groups in the polymer chains, such as amino, carboxyl, and hydroxyl groups, contributes to the hydrogel's water-holding ability. At physiological temperature and pH, these polymeric materials do not dissolve in water, but they do swell significantly in aqueous media. Hydrogel can be manufactured out of almost any water-soluble polymer, and it comes in a variety of chemical compositions and bulk physical properties. Hydrogel can also be made in a variety of ways. Hydrogel comes in a variety of physical shapes, including slabs, microparticles, nanoparticles, coatings, and films. Due to its ease of manufacture and self-application in clinical and fundamental applications, hydrogel has been widely exploited as a drug carrier. Contact lenses, artificial corneas, wound dressing, suture coating, catheters, and electrode sensors are some of the biomedical applications of hydrogels. The pigment color changes were observed from colorless to pale pink followed by dark reddish-pink. Anthocyanin was produced in large quantities and tested using a UV-visible spectrophotometer. At 450-550 nm, the largest peak (absorbance) was detected, indicating the presence of anthocyanin. The FTIR analysis of this study shows the different stretches of bonds at different peaks: 2918.309 (-C-H alkane stretch), 2812.12 (-C-H aldehyde weak intensity), 192320.37/cm (C-O bend), 21915.50, 2029.08/cm (-C=C arene group), 1906.94/cm (=C-H aromatics), 1797.78/cm (=C-H), 1707.94 (-C=O ketene), 1579.70, 1382.96 (C-H alkane strong bend), 889.18/cm (C-H aromatics plane bend), and 412.77/cm (-C-CI strong bond). The spectra of the PVA/chitosan film depict the peak's formation: 1571.88, 1529.55, 1500.62/cm (C-H alkene strong bend), 1492.90, 1483.26, 1467.83/cm (C-H alkene strong bond), 670.48, 443.63, 412.77/cm (-O-H carboxylic acids with great intensity), 1708.93 (-C=O ketone), and 1656.0/cm (alkenyl C=C stretch strong bond).

Influence of extracellular protein isolated from fish gut associated bacteria as an enhancer of growth and innate immune system in Mugil cephalus.

The cultural microbiomes of 27 bacteria colonies were isolated from Mugil cephalus for analysis of the antibacterial and antagonistic activities. A potent probiotic bacterium was characterized using16S r RNA sequencing. The potent strain was added to fish diet to perform the challenge test and to study the growth and immunological parameter. The extracellular proteins from the probiotic were collected and characterized using MALDI TOF/TOF. Out of G27, G9 strain inhibited all the five pathogenic strains. An isolated bacterium was identified as Bacillus subtilis PRBD09 with accession number KF765648. After 35 days of feeding period B. subtilis PRBD09 enhance the both cellular and humoral immune responses, which responsible for survive of the Mugil cephalus against Aeromonas hydrophila infection. The MALDI TOF sample 08 and 09 were recognized as hypothetical proteins based on the MALDI TOF sample. A cytidinedeaminase was found in samples 10, 11, and 12. Extracellular proteins may be involved for the immunological increase in Mugil cephalus against Aeromonas hydrophila, according to the current research.

Bioconversion of chitin waste through Stenotrophomonas maltophilia for production of chitin derivatives as a Seabass enrichment diet.

Marine wastes pose a great threat to the ecosystem leading to severe environmental hazards and health issues particularly the shellfish wastes. The shellfish waste which contains half of the amount of chitin can be efficiently transformed into useful products. Various approaches for the hydrolysis of chitin like physical, chemical, and enzymatic processes are there. Still, the use of enzyme chitinase is well documented as an effective and eco-friendly method. The present study summarizes the isolation of chitinase enzyme producing bacteria from different shrimp waste disposal sites in Parangipettai (India), and the possible use of an enzyme hydrolyzate as an immunostimulant to Asian Seabass (Lates calcarifer). The potential chitinase-producing bacteria were identified by 16S rRNA gene sequencing as Stenotrophomonas maltophilia. After purification, the chitinase specific activity was 5.01 (U/ml) and the protein content was 72 mg and the recovery rate was 48.06%. The optimum pH and temperature for the chitinolytic activity were 6.5 and at 35-50 °C, respectively. The animal experiment trial was done with our feed supplements which included 0.0 (control), 0.5%, 1% and 2% of chitin degraded product. All the supplementary feed had an optimal 42% (w/w) of crude protein. The feed protein level was 41-43% on average and gross energy was 13-17 kcal/g and the feed was observed to exhibit a significantly higher (p < 0.05) survival rate, condition factor, specific growth rates, and body weight gain was also found to be promising compared to other fishes fed with control diet only. The red blood cells (RBC) and white blood cell (WBC) counts were found to increase significantly after being challenged with infection in animals fed with chitin derivatives from 1st week to 3rd week when compared to the control. The hematocrit (Hct) values were low on the 2nd and 3rd week in infected fish fed with chitin derivatives. This low level was due to infection lyses of the red blood cells and increased nitro blue tetrazolium reduction. The control diet-fed fish showed 70% mortality but the chitin derivative supplemented fishes showed only 20% mortality post-infection. The results of the study encompass that the use of chitin-derivate enriched feed further is taken into large-scale approaches thereby benefitting the aquaculture sector.

Bioconversion of chitin and concomitant production of chitinase and N-acetylglucosamine by novel Achromobacter xylosoxidans isolated from shrimp waste disposal area.

Marine pollution is a significant issue in recent decades, with the increase in industries and their waste harming the environment and ecosystems. Notably, the rise in shellfish industries contributes to tons of shellfish waste composed of up to 58% chitin. Chitin, the second most ample polymer next to cellulose, is insoluble and resistant to degradation. It requires chemical-based treatment or enzymatic hydrolysis to cleave the chitin polymers. The chemical-based treatment can lead to environmental pollution, so to solve this problem, enzymatic hydrolysis is the best option. Moreover, the resulting biopolymer by-products can be used to boost the fish immune system and also as drug delivery agents. Many marine microbial strains have chitinase producing ability. Nevertheless, we still lack an economical and highly stable chitinase enzyme for use in the industrial sector. So we isolate a novel marine bacterial strain Achromobacter xylosoxidans from the shrimp waste disposal site using chitin minimal medium. Placket-Burman and central composite design statistical models for culture condition optimisation predicted a 464.2 U/ml of chitinase production. The culture conditions were optimised for maximum chitinase production recording up to 467 U/ml. This chitinase from the A. xylosoxidans was 100% active at an optimum temperature of 45 °C (withstand up to 55 °C) and pH 8 with 80% stability. The HPLC analysis of chitinase degraded shellfish waste reveals a major amino acid profile composition-arginine, lysine, aspartic acid, alanine, threonine and low levels of isoleucine and methionine. These chitinase degraded products and by-products can be used as supplements in the aquaculture industry.

Metagenomic data of vertical distribution and abundance of bacterial diversity in the hypersaline sediments of Mad Boon-mangrove ecosystem, Bay of Bengal.

Bacterial diversity studies in hypersaline soil often yield novel organisms and contribute to our understanding of this extreme environment. Soil from Mad Boon is previously uncharacterized, with dense mangrove forest in one side and hypersaline soil in another side of backwater located in Southeast coast of Tamil Nadu, India. We surveyed to characterize the structure and diversity of the bacterial community. Samples were collected in a partially vegetated upland, exposed backwater sedimentation and water-logged location. In this study, we investigate the bacterial community structure using pyrosequence analysis of the V5- V9 gene region. After quality checks a total of 3919, 7298 and 7399 reads were obtained. About 42 phyla were observed, among them Proteobacteria were dominant phylum followed by Acidobacteria, Firmicutes and Chloroflexi. Classes including Deltaproteobacteria and Gammaproteobacteriawere observed. All sequences generated in this study were submitted to NCBI SRA under the accession numbers SRR627695, SRR63011 and SRR631012.