Jayashree Chakravarty, Ph.D.

The need for developing renewable materials to reduce the reliance on fossil fuels as a feedstock for a wide variety of uses is becoming increasingly widely acknowledged in society. Chitin, the second most abundant nitrogenous natural polymer derived from renewable biomass resources, have attracted significant interest as a promising natural source to produce functional materials due to their unique properties, abundant availability, and environmental appeal. Chitin is present in huge amounts… Show more

The need for developing renewable materials to reduce the reliance on fossil fuels as a feedstock for a wide variety of uses is becoming increasingly widely acknowledged in society. Chitin, the second most abundant nitrogenous natural polymer derived from renewable biomass resources, have attracted significant interest as a promising natural source to produce functional materials due to their unique properties, abundant availability, and environmental appeal. Chitin is present in huge amounts in seafood waste, which is severely underutilized, resulting in resource wastage. An appealing alternative is to upcycle chitin-containing trash into value-added goods, to meet the sustainable development requirements. Since the large quantities of seafood waste remain underexploited, their utilization can potentially bring both ecological and economic benefits. The present review discusses the general properties of chitin and chitosan as natural polysaccharides, highlighting the innovative and eco-friendly methods for recovery of chitin and its derivatives from waste sources. The recent trends of the application of chitin and chitosan in various sectors are explored, highlighting the nexus between the generation and management of seafood waste and its transformation into valuable commercial products as a solution. Show less

Recent advances in science and technology, specifically in the field of material science, nanoengineering and electronic engineering have led to the development of ‘intelligent’ or ‘hi-tech’ textile materials that can sense different environmental conditions and can automatically respond to their surrounding stimuli. These materials have the intrinsic properties of conventional textiles and can also carry additional functional values. With several health care professionals and medical equipment… Show more

Recent advances in science and technology, specifically in the field of material science, nanoengineering and electronic engineering have led to the development of ‘intelligent’ or ‘hi-tech’ textile materials that can sense different environmental conditions and can automatically respond to their surrounding stimuli. These materials have the intrinsic properties of conventional textiles and can also carry additional functional values. With several health care professionals and medical equipment vendors closely tracking smart clothing pilot projects and testing into the new e-textile technologies, the potential of the market for medical textile products and health care is growing steadily. In reality, intelligent clothing holds such promise in health care that it can be seen in the next five years as a big disruptive force in the industry. This chapter explores the development of textile materials as ‘intelligent’ for various applications in monitoring health conditions. The expedited development of this technology to cure medical conditions provides both individuals and society as a whole with clear benefits. Show less

Abstract: This research investigates the potential development of lobster shell waste-derived chitin reinforced with poly(lactic acid) (PLA) and nano-hydroxyapatite (nHAP) into new materials with potentially superior mechanical and thermal properties for biomedical applications. The ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) was used as a solvent to prepare chitin/PLA/nHAP composites. The effect of variation of the polymer concentrations on the conduct of the resulting… Show more

Abstract: This research investigates the potential development of lobster shell waste-derived chitin reinforced with poly(lactic acid) (PLA) and nano-hydroxyapatite (nHAP) into new materials with potentially superior mechanical and thermal properties for biomedical applications. The ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) was used as a solvent to prepare chitin/PLA/nHAP composites. The effect of variation of the polymer concentrations on the conduct of the resulting composite was explored. The detailed physico-mechanical, thermal and surface morphology properties were evaluated with different thermal and optical characterization techniques. When the concentration of PLA in the composite was increased from 20 to 80 wt%, the tensile strength improved by ∼77% while the elongation at break and the toughness of the material decreased significantly. The addition of hydroxyapatite was observed to improve strength of the composites up to 140% with an increase in elongation at break up to 465%. Cell growth study shows that the composite materials support the growth and proliferation of Ocy 454 osteocyte cells. The materials were shown to have no effect on osteocyte gene expression, as well as minimal cytotoxicity and biodegradability. These results reveal that the biocomposites would be suitable candidates for use in bone regeneration that are not exposed to excessive forces. Show less

Abstract: Wound healing is a complex and dynamic process that requires a suitable environment to promote the healing process. Biomaterials have been used to augment and treat tissue wounds and injuries. In this regard, chitin-based materials are receiving increased attention due to their unique and appealing biological properties. Chitin membranes prepared by dissolution of the polymer in ionic liquid (IL) and subsequent freeze-drying were previously shown to be flexible, highly porous, and… Show more

Abstract: Wound healing is a complex and dynamic process that requires a suitable environment to promote the healing process. Biomaterials have been used to augment and treat tissue wounds and injuries. In this regard, chitin-based materials are receiving increased attention due to their unique and appealing biological properties. Chitin membranes prepared by dissolution of the polymer in ionic liquid (IL) and subsequent freeze-drying were previously shown to be flexible, highly porous, and stable. In this work, these membranes were used as support substrates for growth of two mammalian cell types: NIH 3T3 and HEK293T. The membranes did not exhibit any obvious cytotoxicity and supported attachment and proliferation of these cells. Chitin membranes were also used as a matrix for loading and prolonged in vitro release of the antibiotic bacitracin as well as quorum-sensing (QS) inhibitory compounds. These results suggest that the chitin membranes are promising candidates for application in next-generation wound treatment systems and support the concept of using wound dressing materials for tissue engineering and drug delivery purposes, especially for patients suffering from chronic wounds. Show less

Abstract: The application of green chemistry principles for the processing of biopolymers is a steadily increasing field of research. Chitin membranes were successfully prepared by using the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) as solvent media. The resulting materials were thoroughly characterized, revealing that freeze drying produced membranes that were highly porous. The drying methods and the concentration of chitin used defined many of the membrane properties… Show more

Abstract: The application of green chemistry principles for the processing of biopolymers is a steadily increasing field of research. Chitin membranes were successfully prepared by using the ionic liquid 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) as solvent media. The resulting materials were thoroughly characterized, revealing that freeze drying produced membranes that were highly porous. The drying methods and the concentration of chitin used defined many of the membrane properties, such as mechanical strength, porosity, and water absorbency. From these data, an empirical model was generated which could be used to correlate the different membrane properties. The model could be used to predict the properties of the chitin membrane made with different wt% of chitin-IL solutions, and the predicted values aligned with the experimental results. This allowed for prediction of the properties of the chitin membrane (e.g., tensile strength) and gives the ability to tune the properties of the biomaterial. The methods and structures described here provide a starting point for the design and fabrication of a family of polysaccharide-based sustainable materials with potentially broad applicability. Show less

Abstract: Lobster shell waste was used as the source of raw material to produce chitin. Chemical and biological treatments of lobster shell waste were performed. The chemical method required the use of aqueous solutions of HCl and NaOH. Biological treatment included the use of co-cultures with a protease-producing bacterium, either Bacillus megaterium NH21 or Serratia marcescens db11, and an organic acid-producing bacterium Lactobacillus plantarum. The optimal culture conditions, including… Show more

Abstract: Lobster shell waste was used as the source of raw material to produce chitin. Chemical and biological treatments of lobster shell waste were performed. The chemical method required the use of aqueous solutions of HCl and NaOH. Biological treatment included the use of co-cultures with a protease-producing bacterium, either Bacillus megaterium NH21 or Serratia marcescens db11, and an organic acid-producing bacterium Lactobacillus plantarum. The optimal culture conditions, including co-cultivation strategies and glucose concentrations, were identified to improve the efficiency of deproteinization and demineralization of lobster shells. Overall, the successive treatment with a combination of S. marcescens db11 and L. plantarum resulted in the best co-removal of CaCO3 and proteins and chitin yield (82.56%) from lobster shell biomass, with total deproteinization of 87.19% and total demineralization of 89.59%. The results from the proof-of-concept study described here suggest that microbial treatment may be an environmentally friendly alternative to the chemical method of chitin extraction. Show less

Abstract: Microbial production of solvents like acetone and butanol was a couple of the first industrial fermentation processes to gain global importance. These solvents are important feedstocks for the chemical and biofuel industry. Ralstonia eutropha is a facultatively chemolithoautotrophic bacterium able to grow with organic substrates or H2 and CO2 under aerobic conditions. This bacterium is a natural producer of polyhydroxyalkanoate biopolymers. Recently, with the advances in the… Show more

Abstract: Microbial production of solvents like acetone and butanol was a couple of the first industrial fermentation processes to gain global importance. These solvents are important feedstocks for the chemical and biofuel industry. Ralstonia eutropha is a facultatively chemolithoautotrophic bacterium able to grow with organic substrates or H2 and CO2 under aerobic conditions. This bacterium is a natural producer of polyhydroxyalkanoate biopolymers. Recently, with the advances in the development of genetic engineering tools, the range of metabolites R. eutropha can produce has enlarged. Its ability to utilize various carbon sources renders it an interesting candidate host for synthesis of renewable biofuel and solvent production. This review focuses on progress in metabolic engineering of R. eutropha for the production of alcohols, terpenes, methyl ketones, and alka(e)nes using various resources. Biological synthesis of solvents still presents the challenge of high production costs and competition from chemical synthesis. Better understanding of R. eutropha biology will support efforts to engineer and develop superior microbial strains for solvent production. Continued research on multiple fronts is required to engineer R. eutropha for truly sustainable and economical solvent production. Show less

Herbs are used for treatment in Ayurveda. Empirical evidence of efficacy for this “Helminthic database”, would be helpful to health care providers in managing helmenthic patients, and also for identifying future areas of research. Our database “Phyto-helminthesDB”, contains valuable plants for diabetes with their chemical constituents. The active principles of these plants are antioxidant and free radical scavenging mechanisms.

https://www.ncbi.nlm.nih.gov/nuccore/619330702/