Thiagarajan Hemalatha

Recycling of finished leather wastes: a novel approach

Preparation of leather like material, i.e., regenerated leather (RGL) from finished leather wastes is economical and helps in reducing environmental pollution. Incorporating plant fibers (PFs) into RGL enhances its mechanical properties. Plant fibers are exploited as reinforcement materials owing to their low cost, fairly good mechanical properties, high specific strength, non-abrasive, eco-friendly and bio-degradability characteristics. Fiberized leather wastes and PFs were mixed in various proportions to prepare regenerated leather composites (RLCs). Plant fibers viz., coconut, sugarcane, banana and corn silk were used for the study. RGL and RLCs were characterized physicochemically using Fourier transform infrared spectroscopy, thermo gravimetric analysis and scanning electron microscopy. Results clearly portrayed that PFs significantly improved the mechanical and thermal properties of RLCs. Among the composites, RLC prepared using leather waste and coconut fiber (50:40 ratio) proved to be a better composite with potent properties. RLCs are promising for the preparation of leather goods and footwear materials in addition to its cost-effectiveness and environmental pollution abatement.Graphical Abstract

In Vitro Study of Hydroxyapatite Coatings on Fibrin Functionalized/Pristine Graphene Oxide for Bone Grafting

Fibrin functionalized graphene oxide (FGO) and graphene oxide (GO) were used as nucleation sites for the growth of hydroxyapatite (HA). The growth of HA on GO/FGO was done by wet precipitation method, and they were characterized for their physicochemical properties. Cytotoxicity was confirmed by reactive oxygen species assay and cell viability assay; alkaline phosphatase assay, alizarin red test, and protein expression studies showed that FGHA was an excellent composite for osteoblast cell growth and maturation. Alamar blue assay was used to study the enzymatically degraded cytocompatibility of enzymatically degraded components. Results proved that FGHA might be tried as an osteoinductive material, in orthopedic defects.

A possible wound dressing material from marine food waste.

Purpose Bluefin Trevally (Caranx melampygus) fish is mainly used for fillet production, the bones of which are discarded as a major solid waste in the fish food processing industry. In the present study, novel collagen films were prepared using the bones of Bluefin Trevally (BT). The study investigates the potential of using this collagen film as a wound dressing material. Methods The prepared collagen films (CFs) were characterized for their physicochemical properties using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), atomic force microscopy (AFM), tensile strength, elongation at break, etc. In vitro studies using human keratinocyte cell line (HaCaT) also proved the biocompatibility of CF. The CFs were used as wound dressing material on the experimental wounds of rats and the healing pattern was evaluated using planimetric and histopathological studies. Results CF prepared from the bones of BT possessed better mechanical properties. The in vitro studies demonstrated its biocompatible nature. Acceleration of wound healing in CF-treated rats was evident in the in vivo studies. Conclusions The study has devised a process for using fish waste in the preparation of a value-added product like wound dressing material. The CF with the required strength, biocompatibility and wound healing properties may be tried as a wound dressing material in large animals after obtaining the necessary approval.

Leather fibres as reinforcement for epoxy composites: A novel perspective

Developing composite materials with better mechanical and electrical properties is the need of hour, particularly in developing and third world countries. Keeping this objective in view, composite material was prepared, in sheet form, containing leather fibres (LF), isolated from used leather products. Reinforced composite material was produced using LF as reinforcing material for epoxy resin (ER) laminates. To impart additional strength, charcoal carbon nano particles (CCNP) were incorporated (LF:ER:CCNP) in the composite. Fourier transform infrared spectroscopy (FTIR) and thermo gravimetric analysis (TGA) of the samples have revealed the chemical nature and thermal stability of the composites, respectively, while SEM pictures revealed the fiber-matrix interface. LF:ER:CCNP possessed good mechanical properties viz., tensile strength, elongation at break (%), flexural strength, hardness etc, in addition to its electrical property. Hence, the composite possess multifunctional applications, it addition to its cost effectiveness and environmental pollution abatement.

Biphasic calcium phosphate-casein bone graft fortified with Cassia occidentalis for bone tissue engineering and regeneration

Research on traditional herbs is gaining momentum owing to their potent medical properties, among which Cassia occidentalis (CO) is a promising herb, with osteogenic potential. The study investigates the efficacy of CO extract incorporated biphasic calcium phosphate as an osteoinductive material. Prepared bone implants were characterized physico-chemically using FT-IR, TGA, XRD, SEM and EDX. The implants were analysed further for mechanical and biological properties. The results revealed that CO extract-incorporated bone implants possessed better compression strength and it was able to induce proliferation and enhance alkaline phosphatase activity in SaOS-2 cells. The implant proves to be promising for bone tissue engineering, and hence it demands further in vivo evaluation.

Preparation and Characterization of Hydroxyapatite-Coated Selenium Nanoparticles and their Interaction with Osteosarcoma (SaOS-2) Cells

Nanotechnology has taken a firm step to revolutionize the field of orthopedic implants. Current research on bone implants focuses to develop implants with multifaceted functions viz., osteoinduction, chemoprevention, anti-microbial action etc., especially for cancerous bone resection. The objective of the present study was to synthesize a novel composite for bone implants, possessing the above properties. Selenium was selected owing to its chemopreventive and chemotherapeutic properties. Hydroxyapatite was selected owing to its bioactivity and similarity in composition to bone mineral properties. Selenium nanoparticles were prepared by chemical reduction method and coated with hydroxyapatite. Hydroxyapatite-coated selenium nanoparticle (HASnp) was characterized physico-chemically using fourier transform infrared spectroscopy, X-ray diffractometry, scanning electron microscope, and energy-dispersive X-ray spectroscopy. HASnp was analysed in vitro using SaOS-2 cell line. Enhanced cell proliferation and alkaline phosphatase activity were observed in HASnp-treated cells. The results indicate that HASnp is highly suitable for the use in orthopedic applications.

Assessment of expression of Leloir pathway genes in wild-type galactose-fermenting Streptococcus thermophilus by real-time PCR

Abstract In this study, four galactose-positive (Gal+) Streptococcus thermophilus strains viz. AJM, JM1, KM3 and AUKD8 and one galactose-negative (Gal−) S. thermophilus NCDC 218 were used to characterize the organization of Leloir pathway genes using long-range PCR, and expression of these genes were studied using real-time PCR, in presence of different sugars. Long-range PCR results showed that both Gal+ and Gal− isolates, the gal–lac gene order (galRKTEM–lacSZ), are conserved including the size of individual genes. The promoter sequence of the three Gal+ isolates (AJM, JM1 and KM3) possessed single base pair deletion at −28 region of galR and C to T substitution at −9 box galK region. In contrast, Gal+ AUKD8 had A to T substitution at preceding −25 region of galR. The expression of galK and galM grown in the presence of galactose was significantly higher in case of AJM (30- and 7.6-fold, respectively), followed by KM3 and JM1. In addition, galR, galT and galE showed higher expression in galactose, than in lactose and glucose medium. This study gives a preliminary idea on Leloir pathway gene expression in wild Gal+S. thermophilus, and further studies may throw more light on the role of gal–lac operon in galactose metabolism.

Augmentation of therapeutic potential of curcumin using nanotechnology: current perspectives

Abstract Curcumin, an active principle of Curcuma longa, is extracted from the rhizome. Its therapeutic efficiency has been proved using various in vitro and in vivo models. Inflammatory, neoplastic and preneoplastic diseases are the major targets using curcumin as therapeutic agent. Feasible clinical formulations could not be obtained because of its lack of solubility, stability and higher degradation rate. Recently, many techniques have been evolved to improve the physicochemical properties of pharmacological compounds, thereby increasing their biological activity. Curcumin has been developed using various techniques, particularly micro and nanotechnology to improve its stability and bioavailability. This review focuses on the studies pertaining to the delivery of curcumin in the form of micro and nanosize formulations for the treatment of a variety of diseases.

Efficacy of chitosan films with basil essential oil: perspectives in food packaging

Use of edible antimicrobial films in food packaging helps to prevent post harvest decay of food materials. Hence, basil oil—incorporated chitosan films were investigated for this purpose. Basil oil, an important essential oil with antimicrobial and antioxidant properties was added to chitosan in various proportions and their properties were studied. Chitosan was derived from squid pens, a prominent waste of the food processing industry. Antifungal activity was evaluated using four important food pathogenic fungi viz, Aspergillus niger, Aspergillus flavus, Fusarium sp. and Penicillium sp. Chitosan and basil oil individually inhibited the complete growth of the microbes at 0.5% concentration, while their synergistic effect was proved at 0.1%. Thermogravimetric analysis and scanning electron microscopy studies revealed the thermal stability and smooth morphology of the composite films respectively. The antioxidant activity and water barrier properties of the composite films were enhanced due to the essential oil incorporation, while there was a reduction in tensile strength and elongation at break. Thus, the addition of basil oil to chitosan has promisingly improved the film properties thereby making it amenable for food packaging applications.Graphical Abstract

New Approaches for the Effective Utilization of Fish Skin Wastes of Aluterus monoceros

Context: Unicorn leatherjacket (Aluterus monoceros) is an export quality fish mainly used for fillet production, the skin of which is discarded as waste due to its toughness. Wastes emanated from the fish processing industry have become an important source of environmental pollution. Aim: The study investigates the potentials of A. monoceros skin to produce value-added products viz., fish leather and fish meal. Materials and Methods: 5 kg of fish skin from 20 kg of fish was used for the present study. Leather produced from fish skin was characterized for its physico-chemical properties using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), etc. Biochemical components viz., protein, fat, and salt content of the fish skin were also estimated. Results: Leather produced from fish skin possessed 88 MPa tensile strength. Biochemical estimations proved that the fish skin had 28% protein content. Conclusion: On the basis of the characterization and evaluation results, it could be concluded that this processed fish skin could be used for leather goods production. In addition, this fish skin could be included as a component in fish meal preparation.