Present research reports the molecular docking analysis of 2019-nCoV inhibition by antiviral compounds from marine natural resources. For this study, the structure of ligand (antiviral compound) and 2019-nCoV main protease (M^pro) was received from the databases of PubChem and Protein Data Bank (PDB), respectively. Molecular Docking was performed by Autodock version 4.2.6 software. Eight antiviral compounds identified showed inhibitory activities against novel 2019-nCoV protease. Of these compounds, Esculetin ethyl ester (-8.42 kcal/mol) from Marine Sponges Axinella cf. corrugata, has the strongest interaction with the protease enzyme of 2019-nCoV and it may be considered as an effective 2019-nCoV antiprotease drug.

This study was designed to determine the influence of cell bound phytase supplemented in soybean meal on growth and survival of juvenile milkfish Chanos chanos. Four diets were formulated with different levels of fish meal, soybean meal and phytase. The first diet (control) (F) contains 61.35% of fish meal. The fish meal was replaced by the same level of soybean meal in the second (S), third (SP500) and fourth (SP1000) diets, however, SP500 and SP1000 were supplemented with 500 and 1000 phytase activity units (FTU) kg-1, respectively. The replacement of fish meal by soybean meal, with out phytase supplementation reduced weight gain, specific growth rate and crude protein content in the milkfish. The growth performance in fish fed diet SP1000 was as good as those fed diet F. Results indicated that soybean meal supplemented with 1000 FTU kg-1 phytase can be used for the mass culture of milkfish.

Antibacterial compounds from aquatic sources have the potential to contribute significantly to the treatment of the ever-increasing drug-resistant infectious diseases. The chitin 2-acetamido-2-deoxy-hexopyranose from the freshwater prawn Caridina gracilirostris showed antibacterial activity against Staphylococcus aureus. Two different types of chitin films, (1) chitin and starch, and (2) chitin, starch, and ascorbic acid were tested against S. aureus using in silico molecular docking. The inhibitory action of 2-acetamido-2-deoxy-hexopyranose was recorded against the penicillin-binding protein (PBP2a) of S. aureus. The chitin films exhibited their potential as an effective antibacterial agent through binding energy and ligand efficiency. Further, the inhibitory constant also indicated the potent antibacterial nature of the chitin films. The hydrogen bond interaction of chitin with PBP2a was with serine 49 and threonine 413, at 2.2 Å and 3.4 Å, respectively. The druggability of 2-acetamido-2-deoxy-hexopyranose showed good oral bioavailability, and pharmacokinetics properties were within a normal range. The chitin did not undergo any metabolism and appeared to be of a nontoxic nature. The 2-acetamido-2-deoxy-hexopyranose could be suggested as a novel drug against S. aureus.

In this research article we report the potentials of chitin-based silver nanoparticles (chitin AgNPs) derived from Indian mimic goatfish (Mulloidichthys ayliffe) scales as an effective food preservation agent. The study comprehensively presents the multifaceted attributes of chitin AgNPs, including their synthesis, characterization, and antimicrobial properties. Chitin yield from M. ayliffe scales and three-spot swimming crab (P. sanguinolentus) exoskeleton was determined, with the insoluble content quantified. FTIR analysis unveiled distinct absorption peaks for chitin, and scanning electron microscopy revealed the ultrastructure of chitin from both the sources. Using UV–visible spectroscopy, the biosynthesis of AgNPs was accomplished and characterized, with the color shift of the solution serving as proof of a successful synthesis. UV–vis spectra provided insights into nanoparticle size and shape. SEM micrographs exhibited spherical particle morphology, while FTIR spectra indicated amino group interactions contributing to AgNP stabilization. The antimicrobial potential of chitin AgNPs was assessed against the food pathogen, Vibrio spp. Chitin films displayed significant antimicrobial activity, particularly AgNP-synthesized chitin from M. ayliffe scales, demonstrated the highest Vibrio spp. inhibition activity. Furthermore, chitin AgNPs were incorporated into the common chili, Capsicum annuum and the tomato, Solanum lycopersicum to extend their shelf life at room temperature. This study reveals the efficacy of chitin AgNPs from M. ayliffe scales as potent agents for food preservation, offering insights into their physical, mechanical, and antimicrobial attributes. The application of chitin AgNPs to perishable food items highlights their potential in enhancing shelf life and quality, opening innovative avenues for sustainable food preservation.