Antibacterial and anticancer activity of green synthesised silver nanoparticles using polysaccharides extracted from the marine alga Portieria hornemannii

The increasing incidence of cancer cases and multi-drug-resistant bacteria, which are major threats to humankind, forces the research world to innovate new molecules to deal with them.  The main aim of the present work is to prepare silver nanoparticles using macroalgal polysaccharides and to study biological activities. The silver nanoparticles (NPs) were prepared using polysaccharides extracted from the marine macro alga Portieria hornemannii by stirring them with 1 mM silver nitrate after 24 h at 90 ºC. The formed silver nanoparticles were characterized using UV-visible spectrophotometry, Fourier transform infrared spectroscopy (FTIR) analysis, Transmission Electron Microscopy (TEM) analysis, selected-area electron diffraction (SAED), and Energy Dispersive X-ray (EDX) analysis. UV-visible spectrum analysis revealed a surface plasmon peak at 380 nm, showing the development of silver nanoparticles. The nanoparticle size varied between 40 and 50 nm and the functional group was analyzed using FT-IR spectrum. The broadband was observed at 3304 cm-1 (hydroxyl and amino group) and the narrow band was observed at 2907 cm-1 (C–H stretching vibration), 1657 cm-1 (stretching of carbonyl groups), and 1001 cm-1 (C–O stretching vibration). The crystalline nature of silver NPs was confirmed by SAED. EDX analysis reveals the purity and the chemical composition of silver NPs. Nanoparticles were highly effective against Proteus mirabilis (24 mm zone of inhibition) and Bacillus substilis (24 mm zone of inhibition). The anticancer activity of the silver nanoparticles tested against colorectal adenocarcinoma cell lines increased at increasing concentrations of nanoparticles

Production of bioplastic using Jackfruit perianth

Overuse of plastics around the world has made them one of the key environmental concerns today. Disposal of plastic waste in landfills has serious environmental impacts due to its non-biodegradable nature. Agricultural waste, particularly plant materials containing starch gains attraction for its role in the production of alternative biodegradable materials with good tensile strength and other mechanical properties. The present work focuses on production of biodegradable bioplastic using perianth of Jackfruit [Artocarpus heterophyllus Lam. (Moraceae)], which otherwise goes as agro waste. Certain plasticizers are also used to improve the raw materials properties and it was subjected to various tests, to study its mechanical and chemical properties. The sample was characterized using Fourier transform Infrared spectroscopy (FTIR) and tensile strength was also checked. It was subjected to various resistance tests such as water resistance, alcohol resistance, flammability, alkali and acid resistance and it was confirmed that the bioplastic produced from Jack fruit perianth is a good option to normal plastics

Plasmon-mediated, highly enhanced photocatalytic degradation of industrial textile dyes using hybrid ZnO@Ag core–shell nanorods

Hybrid ZnO@Ag core–shell heterojunction nanorods were synthesized using a novel, facile two-step process based on hydrothermal and seed mediated growth techniques. The material was characterized by UV-visible spectroscopy, Fourier transform-infrared spectroscopy (FT-IR), room temperature photoluminescence spectroscopy (RTPL), Raman spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). The hybrid ZnO@Ag core–shell nanorods were comprised of one-dimensional (1D) ZnO nanorods serving as a core material, over which surface-doped Ag nanoclusters (2.5 nm) were anchored as a heterogeneous shell. The presence of oxygen vacancies and Zn interstitials were confirmed by RTPL and Raman spectroscopic analysis. The photocatalytic activity of the hybrid ZnO@Ag core–shell nanorods was studied in comparison to bare ZnO nanorods using standard R6G dye and industrial textile dyes such as Congo red and Amido black 10B under UV and visible light (solar) irradiations. Moreover, the material was tested for real time industrial textile effluents under ambient conditions and was found to be highly efficient. The enhanced photocatalytic property observed for ZnO@Ag hybrid core–shell nanorods is attributed to a phenomenal increase in oxygen related defects in the core that generate photo-induced charge carriers and the presence of plasmonic Ag nanoclusters in the shell, which act as a sink for the photo-induced charge carriers

Bioremediation: A Novel Tool for Environment Friendly Shrimp Aquaculture

Bioremediation: A Novel Tool for Environment Friendly Shrimp Aquacultur

A Versatile Route for the Synthesis of Nickel Oxide Nanostructures Without Organics at Low Temperature

Nickel oxide nanoparticles and nanoflowers have been synthesized by a soft reaction of nickel powder and water without organics at 100 °C. The mechanism for the formation of nanostructures is briefly described in accordance with decomposition of metal with water giving out hydrogen. The structure, morphology, and the crystalline phase of resulting nanostructures have been characterized by various techniques. Compared with other methods, the present method is simple, fast, economical, template-free, and without organics. In addition, the approach is nontoxic without producing hazardous waste and could be expanded to provide a general and convenient strategy for the synthesis of nanostructures to other functional nanomaterials

Protocol developed for the hatchery production of marine model fish Oryzias dancena (Hamilton, 1822)

A non-human species that has been widely studied in the laboratory for helping scientists understanding the biological processes is called a ‘model organism’. Their inherent characteristics include easy maintenance, anatomical and physiological similarities to humans, high reproductive rate and large offspring number, and a short generation time (the time period from birth to reproduction). Among the fishes, zebra fish (Danio rerio) is widely accepted globally as a model organism for research in freshwater providing valuable insights into cell, tissue, organ, and system level. However, for studies involving marine and brackish waters, it is not advisable to superimpose the cues obtained from freshwater model organism, which necessitates the use of a species with marked euryhaline characteristics. Oryzias dancena (Hamilton, 1822), with tolerance to varying salinities, are small and easy to bred, and are capable of being maintained in large numbers; therefore offers as an excellent alternate fish model organism for experiments in marine systems

Preliminary estimates of potential areas for seaweed farming along the Indian coast

India has enormous potential for seaweed mariculture; however, mass scale commercial farming of seaweeds is yet to take off successfully in the country. R&D efforts over the years have resulted in techno-scientific improvements in farming technologies such as floating rafts, net-tubes, long-lines, and cage based IMTA systems for seaweed culture. However, a few challenges remain, particular in identifying potential sites, its demarcation and developing suitable and sustainable spatial plans for seaweed farming on a country-wide, commercial perspective. In view of the emerging importance of seaweed mariculture and policy thrust by the Government of India, an all India preliminary site selection survey suitable for seaweed farming was conducted by ICAR-CMFRI along all maritime states of India. From this survey a total of 23,970 ha area were identified as potential seaweed farming along the Indian coast. In the present article, we present details of the suitable sites and its demarcation on a preliminary spatial map for facilitating the imminent expansion and effective adoption of seaweed farming in the country

Evaluation of the effect of incorporation of dibutyryl cyclic adenosine monophosphate in an in situ-forming hydrogel wound dressing based on oxidized alginate and gelatin

Cyclic adenosine monophosphate (cAMP) has long been regarded as a second messenger and a regulator of human keratinocyte proliferation. To explore more effective wound management, dibutyryl cyclic adenosine monophosphate (DBcAMP), a lipophilic analog of cAMP was incorporated into an in situ-forming hydrogel wound dressing based on periodate-oxidized alginate and gelatin. In vitro release of DBcAMP from the matrix into phosphate buffered saline was slow and increased with time. Only 50-60% of the compound was released into the medium over a period of 2 days suggestive of a sustained release into the wound bed over a period of few days. The wound-healing efficacy of the DBcAMP-incorporated dressing was evaluated on experimental full-thickness wounds in a rat model. It was found that dressing promoted wound healing leading to complete re-epithelialization of wounds within 10 days, whereas control wounds took 15 days for complete re-epithelialization. Data obtained in this study showed that the presence of DBcAMP accelerated healing and re-epithelialization of full-thickness wounds