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Herein, the leather waste-based gelatin composite film reinforced with cellulose II nanocrystal (CNC II) extracted from wet wipes using three different hydrolysis techniques is explored for its functional properties. CNC II isolated using peroxide (PCNC), citric acid (CCNC) and hydrochloric acid (HCNC) differed in morphological and crystalline character as investigated using DLS, FE-SEM, FTIR and XRD analysis. The crystallinity of PCNC, CCNC and HCNC was found to be 81.1%, 75.4%, and 86.1%, respectively. The highly crystalline CNC II (PCNC) incorporation improved mechanical stiffness of raw hide trimming waste-based gelatin films by 50% compared to control gelatin film. Maximum thermal stability with T max of 329 ºC was obtained for gelatin films with PCNC nano-reinforcement. Strong interfacial hydrogen bonding interactions between gelatin and cellulose II nanocrystal existed and modified the properties of the film. Incorporation of CNC II reduced the surface wettability of the films and absorbed UV radiation as evidenced by transmittance value T280 of 0.19. Nanocomposite films degraded up to 79.9% of initial mass under 7 days of soil burial. Single use packaging application of garden eggplant seed has been demonstrated.

The present study involves the development of citric acid-cross-linked carboxymethyl cellulose (C3CA) scaffolds by a freeze-drying process. Scaffolds were fabricated at different freezing temperatures of -20, -40, or -80 °C to investigate the influence of scaffold pore size on bone regeneration. All three scaffolds were porous in structure, and the pore size was measured to be 74 ± 4, 55 ± 6, and 46 ± 5 μm for -20, -40, and -80 °C scaffolds. The pores were larger in scaffolds processed at -20 °C compared to -40 and -80 °C, indicating the reduction in pore size of the scaffolds with a decrease in freezing temperature. The cytocompatibility, cell proliferation, and differentiation in C3CA scaffolds were assessed with the Saos-2 osteoblast cell line. These scaffolds supported the proliferation and differentiation of Saos-2 cells with significant matrix mineralization in scaffolds processed at -40 °C. Subcutaneous implantation of C3CA scaffolds in the rat model was investigated for its ability of vascularization and new matrix tissue formation. The matrix formation was observed at the earliest of 14 days in the scaffolds when processed at -40 °C while it was observed only after 28 days of implantation with the scaffolds processed at -20 and -80 °C. These results suggest that the citric acid-cross-linked CMC scaffolds processed at -40 °C can be promising for bone tissue engineering application.

Inhibition of collagen fibrillation by small molecules is of growing interest to develop therapeutics for the illnesses related to excess deposition of collagen. In this context, we have studied the inhibitory effect of N-Vanillylnonanamide (NVA), a natural product from capsicum oleoresin and an analog of capsaicin (a known inhibitor of collagen fibrillation), on collagen self-assembly that leads to fibrillation in vitro. Commercially, capsaicin was found to be expensive than NVA. Therefore, it would be an advantage economically if NVA could display a similar/better inhibitory activity compared to capsaicin. The conventional turbidity measurements indicate that NVA completely inhibits collagen fibrillation at body temperature (37 °C) and its inhibition were concentration-dependent. The inhibition efficiency was observed to reduce at room temperature (25 °C). NVA protects the triple helical structure of collagen while it increases the thermal stability of collagen compared to collagen alone. Fluorescence results suggest that NVA binds in both telopeptide and triple helical regions of collagen and thereby prevents collagen self-assembly. The present results thus indicate that NVA is a potential inhibitor and, economically, it could be a better choice as a therapeutic agent compared to capsaicin in evolving treatment for disorders associated with excessive collagen deposition.

Sustainable management plays a vital role in the emerging world, reproducing a pollution-free environment and leading to sustainable growth. In that aspect, leather industries are cornered toward greener leather processes to reduce chemical and water usage. On the same path, deliming is one of the significant steps in the pretanning process to drive into a greener process because the conventional deliming process requires 4% ammonium salts and 100% water, which leads to an enormous amount of ammonium salts in wastewater, leading to eutrophication which adds to the pollution load. To reduce the pollution load, in this work a chemical and water-free deliming process is performed using supercritical carbon dioxide (SCCO₂) as a medium as well as deliming agent to remove the lime content from goat skin at 75 bar pressure within 10 min. Also, the utilized CO₂ is collected and reused for the subsequent set of processes. The morphological analysis shows no grain damage on delimed pelts processed using SCCO₂, and leathers post-tanned from this system exhibit better organoleptic and mechanical strength properties. The developed process opens newer vistas for sustainable development in leather manufacture.

Salt-based preservation of hides/skins contributes to about 50% total dissolved solids (TDS) in tannery wastewaters. In this study, raw skins have been preserved by exposing them to a continuous flow of supercritical carbon dioxide (SCCO2) in a pressurized reactor. The process was carried out in reactors of two different capacities to ensure scalability. The skins thus dried could be stored at room temperature for a period of 30 days. The SCCO2–dried skins were less conducive for microbial growth than wet-salted skins. The soak liquor of SCCO2–dehydrated skin showed a 90% reduction in chloride content and significantly lower BOD and COD levels than soak liquor from wet-salted skins. The leathers produced from SCCO2-preserved skins and wet-salted skin had no significant quality differences. As SCCO2 systems have been reported as alternatives to all other unit operations, establishing SCCO2–based preservation will complete the circle of total leather manufacture with SCCO2.

Hair waste is one of the solid substances rejected by the leather industry. This waste finds its way into the surroundings causing serious environmental pollution. This hair waste may be utilized for effective extraction of keratin, thereby generating value-added products with numerous applications. Thus we focusing on utilizing red sheep’s hair waste for extracting keratin by the application of different chemical treatments such as sodium hydroxide, sodium sulfide, mercaptoethanol, cysteine, sodium metabisulfite with urea (SMB), and SMB with SDS (SMBS). CD spectrum and FTIR results of the keratin samples indicated a predominance of the helical conformation along with β sheets. SDS-PAGE confirmed the molecular weight of the keratin samples to be in the range of 40–60 kDa. DSC and TGA analysis exhibited the extracted keratin to have a higher denaturation temperature (>200 °C) and thermal stability. The keratin samples obtained using varied chemical treatments were compared in terms of yield, protein content, and cost-effectiveness, and the sample obtained using SMBS was preferred for in vitro studies. It is indicated that keratin extracted using SMBS effectively involved for fibroblast cell growth. Thus, we suggest that these keratin could produce biomaterials that can serve as a valuable material for biomedical applications.

Fibrous structures, in general, have splendid advantages in different forms of micro- and nanomembranes in various fields, including tissue engineering, filtration, clothing, energy storage, etc. In the present work, we develop a fibrous mat by blending the bioactive extract of Cassia auriculata (CA) with polycaprolactone (PCL) using the centrifugal spinning (c-spinning) technique for tissue-engineered implantable material and wound dressing applications. The fibrous mats were developed at a centrifugal speed of 3500 rpm. The PCL concentration for centrifugal spinning with CA extract was optimized at 15% w/v of PCL to achieve better fiber formation. Increasing the extract concentration by more than 2% resulted in crimping of fibers with irregular morphology. The development of fibrous mats using a dual solvent combination resulted in fine pores on the fiber structure. Scanning electron microscope (SEM) images showed that the surface morphology of the fibers in the produced fiber mats (PCL and PCL-CA) was highly porous. Gas chromatography–mass spectrometry (GC-MS) analysis revealed that the CA extract contained 3-methyl mannoside as the predominant component. The in vitro cell line studies using NIH3T3 fibroblasts demonstrated that the CA-PCL nanofiber mat was highly biocompatible, supporting cell proliferation. Hence, we conclude that the c-spun, CA-incorporating nanofiber mat can be employed as a tissue-engineered construct for wound healing applications.

β-Cyclodextrin (β-CD), a macrocyclic oligosaccharide cavitand, is a well-known candidate for drug delivery and formulation. In this study, we extended the application of β-CD using a β-cyclodextrin sulfate (β-CDS) as a possible therapeutic for fibrotic diseases caused by excess deposition of collagen fibrils. We have strategically chosen β-CDS, which mimics the natural existence of dermatan sulfate in the extracellular matrix, for limiting collagen fibrillation. The hydrophobic nature of the inner core β-CDS is expected to form an inclusion complex with hydrophobic side chain amino acids with the simultaneous action of forming an ionic bond through a negative charge on sulfate group with positively charged amino acids side chain in collagen. Various results suggested that such dual action not only limited the collagen fibrillation but also reduced the fibril size formed in the presence of β-CDS. The contemporary results thus indicate that β-CDS can be explored as a therapeutic molecule in fibrotic diseases.

Zinc Oxide (ZnO) nanoparticles are used in the field of nanomedicine. ZnO is non-toxic and compatible with biological system. The major problem of wound is infections. The infections delays wound healing. Usage of Nanomaterials like ZnO nanoparticles for wound healing is promising. ZnO nanoparticles are synthesised by wet chemical method. It is annealed at 300, 500, 700, and 900 °C for 3 h. ZnO nanoparticle morphology and size distribution are analysed by XRD, FTIR and TEM. The influences of particle size on fibroblast cell growth (NIH3T3) and on antimicrobial activity are analysed. The growth of fibroblast cell is higher with ZnO nanoparticles of larger particle size. Further the MTT analysis, fluorescence calcein AM cell staining and F-actin analysis confirms the growth of fibroblast cells with improved biocompatibility behaviour. The antimicrobial activity is higher for ZnO nanoparticles of lower particle size. Confocal microscope analysis and Zone of inhibition analysis confirms the antimicrobial activity of ZnO nanoparticles.

Biomimetic nanofibrous scaffolds targeting multiple dysfunctional processes provide a multi-pronged strategy to restore functions and regenerate the damaged tissue. This study investigates a strategy of combining a regenerative component, Type I collagen Peptide (CP), along with a nitric oxide donor, S-Nitrosoglutathione (GSNO), in the form of nanofibrous scaffold to address the non-healing diabetic ulcer. Silk Fibroin-Polyvinyl alcohol (SF-PVA) nanofibrous scaffold is used as a carrier for delivering functional moieties. The developed nanofibrous electrospun mats (SF-PVA, CP-SF-PVA, and CP-GSNO-SF-PVA) showed continuous, bead-less and randomly oriented fibers with highly porous morphology. The in vitro biocompatibility was assessed by MTT assay, DAPI-Rhodamine 123 and FITC-Phalloidin imaging studies. CP-GSNO-SF-PVA nanofibrous scaffold showed a high degree of cell attachment, spreading of F-actin with viable cell morphology and appreciable inter-cellular connection. Thus the study showed that the proliferation of fibroblast cells are mainly facilitated by the presence of collagen peptide in the nanofibrous matrix. Griess assay demonstrated immediate release of NO for a day from the developed multifunctional scaffold. These results demonstrate the in vitro efficacy of CP-GSNO and indicate the opportunity of CP-GSNO-SF-PVA nanofibrous scaffold for the treatment of ischemic non-healing ulcers.

Accumulation of hair waste is a major burden to the leather industry, causing a negative impact on the industry's sustainable development. The industry is already bogged down by the usage of synthetic re-tanning agents that are not only extremely challenging for biodegradation but also release free-form of formaldehyde in the final leather stage. This research work focuses on developing a formaldehyde-free bio-based re-tanning agent from hair waste. In order to do so, hair waste is subjected to alkali hydrolysis and subsequently graft-copolymerized with methacrylic acid (MAA). These treatments were optimal using 20 % (w/w) sodium hydroxide and thermal activity at 90 °C. This resulted in effective hydrolysis of red sheep hair, which was the ideal candidate in this study. The hydrolysate was subjected to monomer in situ polymerization (using MAA) with potassium per sulfate/sodium meta-bisulphite redox system, leading to the development of keratin hydrolysate-g-methacrylic acid (KH-g-MA) copolymer (this was noted both at a laboratory level and pilot scale). The obtained KH-g-MA copolymer exhibited ideal characteristics such as increased protein content (78.3 ± 1.2), appropriate particle size (1516 nm), suitable pH (5) and required viscosity of 512 cP. The developed KH-g-MA copolymer was then applied as a re-tanning agent in the leather manufacturing process. Significant improvement in leather's mechanical strength characteristics was observed. In addition, the organoleptic properties of leather such as fullness, softness and grain tightness showed much improvement. Scanning electron microscopy (SEM) showed an enhanced surface smoothness and filling of the voids in experimental leather in comparison to the control leather. This recycle and reuse strategy of hair waste not only helps resolve issues with handling of hair solid waste but also results in producing an eco-friendly re-tanning agent in leather manufacturing, thereby paving the way for cyclic economic utilization and cleaner environment.

Here we report the preparation of biomimetic fibrin/chitosan/keratin hybrid scaffolds with a synergistic combination of ferulic acid loaded silica microspheres for antimicrobial wound dressing applications. The infrared and X-ray powder diffraction studies confirm the homogenous nature of the prepared hybrid scaffolds without any major interactions between the constituents. The developed hybrid scaffolds show good thermal, porosity, compression and water uptake properties. Scanning electron microscopic analysis shows that the as-synthesized ferulic acid loaded silica microspheres exhibit an average size of 35 ± 10 μm and also exposes the smooth surface with interconnected porosity in the prepared hybrid scaffolds. The incorporated ferulic acid loaded silica microspheres hybrid scaffolds show effective antimicrobial activity against the common wound pathogens. In vitro NIH3T3 fibroblast cell culture and drug release studies reveal that the prepared hybrid scaffolds have enhanced cell proliferation and adhesion with a prolonged drug release for about 72 h. In vitro wound healing and actin cytoskeleton analysis reveal that the incorporated ferulic acid loaded silica microspheres in fibrin/chitosan/keratin hybrid scaffolds facilitates cell growth and migration to damaged area through cell-cell interactions. These results suggest that the prepared hybrid scaffolds with ferulic acid loaded silica microspheres have great potential for soft tissue engineering applications particularly for the treatment of chronic and infected wounds.

Hybrid silver (Ag)–gold (Au) nanoparticles (NPs) with different sizes and compositions were synthesized. Ag/Au alloy and Ag@Au core–shell type NPs were prepared from Ag and Au with various ratios using the COCO gemini surfactant, 1,6-bis (N,N-hexadecyldimethylammonium) adipate (COCOGS), 16-6-16 as a stabilizer. The formation of the Ag/Au alloy and Ag@Au core–shell was confirmed by UV-visible absorption spectroscopy, high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDX) and selected area electron diffraction (SAED) patterns. Depending on the composition of the Ag/Au alloy NPs, the λmax values varied from 408 nm to 525 nm. FTIR measurements were used to evaluate the adsorption of the COCO gemini surfactant (16-6-16) on the Ag/Au alloy and Ag@Au core–shell surface. In this present work, we study how to achieve the stability and activity of the COCO gemini surfactant (16-6-16) capped Ag/Au alloy and Ag@Au core–shell NPs for developing novel anti-cancer agents by evaluating their potentials in the Hep-2 cell line model. Thus the developed core–shell NPs were possibly involved in inducing cytotoxicity followed by inhibition of cell proliferation to the cancer cells with apoptosis induction. The developed core–shell NPs might serve as highly applicable agents in the development of next-generation cancer chemotherapeutic agents.

Development of biomaterials for tissue engineering applications is of great interest to meet the demand of different clinical requirements. The wound heal dressing biomaterials should necessarily contain well-defined therapeutic components and desirable physical, chemical and biological properties to support optimal delivery of therapeutics at the site of the wound. In this study, we developed collagen-silica wound heal scaffold incorporated with the extract of Cynodon dactylon, characterized and evaluated for its wound heal potential in vitro and in vivo against collagen (Col) and Collagen-silica (CS) scaffolds that served as controls. The prepared Collagen-Silica-Cynodon extract (CSCE) scaffold exhibits porous morphology with preferable biophysical, chemical, mechanical and mass transfer properties besides its controlled biodegradation at the wound site. Stability of CSCE was found to be better than that of native collagen due to intermolecular interactions between collagen and constituents of C. dactylon as confirmed by FTIR analysis. Notably, in vitro biocompatibility assay using DAPI and Rhodamine 123 staining demonstrated that the proliferation of NIH3T3 fibroblast cells was better for CSCE when compared to the Col and CS scaffolds. In vivo wound healing experiments with full-thickness excision wounds in wistar rat model demonstrated that the wounds treated with CSCE showed accelerated healing with enhanced collagen deposition when compared to wounds treated with Col and CS scaffolds, and these studies substantiated the efficacy of CSCE scaffold for treating wounds.

Collagen is a unique protein abundantly present in the connective tissues of mammals and widely used for biomaterial preparation. In this study, we synthesized and characterized collagen-fucoidan blend films for tissue regenerative properties. Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) were used for thermal analysis of the blend films, and the films exhibited higher thermal stability and denaturation temperature (Td) than those of native collagen due to intramolecular hydrogen bonding interaction between collagen and fucoidan, which was analyzed by FTIR spectroscopy. Morphological evaluation of these films using Scanning Electron Microscopy (SEM) showed smaller pore size than the control. Moreover, fucoidan protects collagen against enzymatic degradation and thereby increases the structural stability of collagen. Further, the in vitro studies of the synthesized films showed that they effectively facilitated the proliferation and migration of fibroblast cells without exhibiting toxicity. These study results suggested that the collagen-fucoidan blend films are a favorable substrate for growth of fibroblast cells, and may have great potential for tissue engineering applications.

Intensifying researches in leather sector are focusing on eco-benign tanning chemicals with less environmental impact processing route. The present study aims to design an eco-acceptable shoe upper leather process that could potentially eliminate use of chrome from the leather industry. Possible conversion of Cr3+ to Cr6+ in suitable oxidant environment during leather manufacture is always a threat to the ecosystem. Water load for leather processing is very high, also becoming a precious resource that needs to be reduced for industrial applications. Further without water usage for a process, generation of wastewater could be averted. With this context, a combination tanning using wattle and aluminium has been developed in a pickle-less and waterless medium. The experimental leather possesses a shrinkage temperature of 84 °C with a fully loaded compact fibre structure indicating that tannin penetration is not affected in waterless medium. Experimental leathers exhibit better physical strength and comparable organoleptic characteristics. The process enjoys environmental benefits as it shows significant pollution load reduction in Biological Oxygen Demand (BOD), chemical oxygen demand (COD), Total Dissolved Solids (TDS) by 88, 89, and 97%, respectively. Hence, a viable option is made available to manufacture eco-acceptable leather without water usage and chrome salts in tanning.

Solid waste from all walks have registered their environmental impact by breathing out large amount of greenhouse gases. In this work, not only a waste to wealth strategy for effective utilization of trimmings (Solid waste) from tanning industry to recover gelatin is depicted, but also to use the extracted bio-polymer to develop a product alternative to non-biodegradable plastics. Ability of gelatin to form films is capitalized in the preparation of a composite film system comprising equal percentage ratios of gelatin (Gel) and poly vinyl alcohol (PVA) through solvent casting method. This Gel/PVA composite film is envisaged for producing sustainable packaging film materials. As the existing packaging film materials sourced from petroleum based products cause degradation and disposal concerns, the proposed value addition on the gelatin extracted from waste can be a greener alternative. Through progressive optimizations Gel/PVA film system was incorporated with percentages of glycerol (Gly) and glutaraldehyde (GA) to have performance similar to the low density polyethylene (LDPE) film taken as control. Mechanical, analytical, thermal sealability and printability tests on the developed composite film Gel/PVA/Gly/GA gave optimum results for packaging applications.

We report a novel method that exploits the differential solubility properties of native and denatured proteins to distinguish between them. We chose to study this using collagen because its unique native triple helical structure is critical for the desired properties of collagen-based biomaterials. We found that native and denatured collagen separate out from solution in alcohols(methanol, ethanol, n-propanol and isopropanol), but as different phases. Native collagen undergoes tight gel-like separation(macrophase) from the solution in alcohols(90%,v/v), whereas denatured collagen separates as particles(microphase), which turn milky-like turbid. It was found that the pH of the medium had to be alkaline for turbidity formation, which necessitated the use of buffered alcohols. In solutions having mixtures of native and denatured collagen, the method has sensitivity to visually confirm the presence of native collagen even as low as 10%. It was also confirmed that the formation of turbidity was a direct function of the concentration of denatured collagen. A thermal denaturation experiment, wherein stages of denaturation were studied both by the proposed method and circular dichroism, showed that information obtained from both methods of analysis was comparable. This highlights the potential of the proposed method to become an instant fool proof test for collagen.

Bioactive compounds are extracted from mekmeko and characterized for antioxidant, phytochemical, and antibacterial activities. The phytochemical studies of the extracts revealed the presence of condensed tannins, flavonoid, and phenolic compounds. Radical scavenging activity of the extract demonstrates that the ethanol extract has more significant antioxidant activity than the aqueous extract. Ethanolic extract of mekmeko is more effective against gram-positive bacteria compared to gram-negative. A Box–Behnken-design was used to study the response pattern and to determine the optimum combination of variables for maximization of extraction yield. Experiments were carried out to evaluate the four independent variable effects (particle size, temperature, time, and solid–solvent-ratio) on the maximum extraction yield of bioactive compounds. Second order polynomial mathematical model was developed with a high coefficient of determination ( R 2 = 0.99) from the experimental data. A maximum of 18.85% total extraction yield was achieved at the optimal conditions of particle size of 350 mesh, extraction temperature at 41 °C, solid–solvent-ratio of 0.07, and extraction time of 24 h. The extracted constituents are predominantly phenolics (39%) and condensed tannins (21%). Under theses optimal conditions, the experimental values agreed well with the predicted values and indicated the suitability of the developed models.

The present study is aimed to study and to evaluate the colon cancer targeting efficacy of chitosan-coated-trans-resveratrol (RSV) and ferulic acid (FER) loaded SLNs (solid lipid nanoparticles) that conjugated with folic acid (FA) (C-RSV-FER-FA-SLNs) in suitable models (in vitro). The FA conjugation is performed using co-encapsulation method of stearic acid. Similarly, the prepared SLNs are exhibited better stability even under acidic conditions to exhibit their potentials to use as drug delivery system. Further, the optimized formulations (SLNs) are tested for physiochemical characterizations, which include FTIR, XRD, 1HNMR, particle size, zeta potential, and drug release. In vitro anti-cancer studies using HT-29 cells including, fluorescence staining, flow cytometry, and western blot analysis revealed that the C-RSV-FER-FA-SLNs effectively involved and increased cytotoxicity in cancer cells that leads to induction of apoptosis as compared to free RSV-FER. Thus, it is reported that, the good stability under acidic conditions of this C-RSV-FER-FA-SLNs may serve as a promising candidate for novel nanodrug formulations in cancer therapy.

Raw hides and skins are preserved before processing them into leather, to protect the skin protein from microbial attack. The salting method of preservation using about 50% w/w common salt is the most popularly practiced preservation method worldwide. This conventional system results in high saline wastewater leading to a huge amount of pollution load in terms of total dissolved solids and chlorides which is discharged into the effluent during the soaking process in leather manufacture. In order to overcome these wastes problem at their source, researchers have been involved in search of alternative preservation methods using salt-less or less-salt options. In the present study, the herbal Rumex abyssinicus (mekmeko) roots, which were shade dried at room temperature and powdered was investigated for its effectiveness in the preservation of goat skins. The efficacy of this new preservation method was assessed at different curing period for a month. In the assessment, the following parameters viz., moisture content, extractable nitrogen content, soluble hydroxyproline, hydrothermal stability, bacterial count, and visual evaluation of skins (hair slip and putrefaction odor) were assessed. The mekmeko preservation experiments were compared with parameters obtained using the conventional curing method. After 30 days of preservation, the experimental and control skins were processed into upper leather and their quality was evaluated by analyzing the physical characteristics, organoleptic properties and fiber structure using scanning electron microscope. The results showed that the curing system using 10% mekmeko powder with 15% common salt is efficient in preserving the raw goat skins. The quality of the experimental crust leathers produced from the optimized preservation system is comparable with the control leathers. The generation of the pollution load during leather processing was determined by analyzing biochemical oxygen demand, chemical oxygen demand, total dissolved solids, and chlorides from soaking liquor. Most importantly, 55% total dissolved solids and 70% chloride reduction in the soaking liquor was achieved by using the plant-based method of preservation. The less-salt preservation system based on mekmeko is a cleaner alternative for the conventional salt-based preservation method.

Ulcerative colitis, particularly the chronic persistent form is characterized by the presence of active inflammation and extensive areas of ulceration in the colonic mucosa. The existing treatment protocol aims at only reducing intestinal inflammation, rather than targeting mucosal ulceration. In this study, type I collagen and its daughter peptides called collagen hydrolysate, highly popular reconstructive materials for tissue engineering applications, are hypothesized as healing matrices to target the recuperation of internal mucosal ulceration. The clinical assessments on day 10 of dextran sodium sulfate induced colitis in mice model revealed that both the collagen (1.56±0.29) and collagen hydrolysate treatments (1.33±0.33) showed a significant reduction in the rectal bleeding compared to the reference mesalamine treatment (2.50±0.33) and untreated negative control (2.40±0.40). VEGF, a potent angiogenic growth factor, over expressed during UC was down-regulated by collagen hydrolysate (1.06±0.25) and collagen (1.76±0.45) to a greater extent than by mesalamine (2.59±0.51) and untreated control (4.17±0.15). The down-regulation of proinflammatory cytokines such as TNF-α, IL-1β, and IL-6 also follows the same pattern. Histological observations were in accordance with the clinical indicators. Both collagen and collagen hydrolysate treatments showed significant reduction in mucosal damage score and facilitated faster regeneration of damaged mucosa.

Human life expectancy has been steadily increasing at a rapid rate, but this increasing life span also brings about increases in diseases, dementia, and disability. A global burden of disease 2010 study revealed that hip and knee osteoarthritis ranked the 11th highest in terms of years lived with disability. Wear and tear can greatly influence the quality of life during ageing. In particular, wear and tear of the articular cartilage have adverse effects on joints and result in osteoarthritis. The articular cartilage uses longevity of type II collagen as the foundation around which turnover of proteoglycans and the homeostatic activity of chondrocytes play central roles thereby maintaining the function of articular cartilage in the ageing. The longevity of type II collagen involves a complex interaction of the scaffolding needs of the cartilage and its biochemical, structural and mechanical characteristics. The covalent cross-linking of heterotypic polymers of collagens type II, type IX and type XI hold together cartilage, allowing it to withstand ageing stresses. Discerning the biological clues in the armamentarium for preserving cartilage appears to be collagen cross-linking. Therapeutic methods to crosslink in in-vivo are non-existent. However intra-articular injections of polyphenols in vivo stabilize the cartilage and make it resistant to degradation, opening a new therapeutic possibility for prevention and intervention of cartilage degradation in osteoarthritis of aging.

Discharge of huge quantities of raw skin/hide trimming wastes by leather industries has raised serious concerns on account of their environmental impacts. It is imperative to develop a simple method for the utilization of this waste to provide a practically feasible and economically viable solution. The trimmings contain high amount of fibrous protein, which are actually a valuable bioresource. The study presents the extraction of collagen, a product of high value, from raw trimmings. Experiments were carried out using propionic acid and acetic acid for the solubilisation of collagen from skin matrix. Of these acid extraction methods, propionic acid method showed higher yield of collagen (∼93%) compared to the acetic acid extraction (∼85%). The extracted collagen was further characterised by physicochemical techniques such as SDS-PAGE, circular dichroism and infrared spectroscopy. It was concluded that the collagen extracted from trimming waste using both acids were of type I and also found to have similar physicochemical properties. Therefore, the raw skin/hides trimming waste can be a cheap source of collagen, which has many high end applications like tissue engineering, biomaterials, cosmetics and pharmaceutical industry.

Silk based biomaterials have been explored as a natural-based system for tissue regeneration. Biocomposite sheets were fabricated by controlled deposition of hydroxyapatite (HA) on porous silk cocoon structure through precipitation method using calcium chloride dihydrate and disodium hydrogen phosphate anhydrous solutions. The formation of hydroxyapatite coating on the silk sheets was confirmed by the presence of characteristic apatite peaks in the XRD patterns. The interactions between HA and silk proteins were evidenced by a shift in the amide peaks of biocomposites as observed from the IR spectra. The mineralisation of silk sheets did not alter their thermal stability as revealed from the thermogravimetric analysis. Scanning electron microscopy of the silk sheets showed the growth of hydroxyapatite on the surface of fibrous silk networks. The tensile strength of the biocomposite sheets is decreased to 21-30 MPa when compared to native silk sheets that had 32 MPa. The properties of silk cocoon-hydroxyapatite biocomposite sheets indicate its potential as a suitable substrate for bone tissue engineering application.

Leather is extensively used in the production of various lifestyle accessories such as shoes, bags, garments, upholstery, and various other products. The leather waste generated from the manufacturing units of leather and after the intended usage of the leather products leads to the accumulation of solid leather wastes. The studies on making the leather amenable for easy disposal is a priority research. A unique process prepared for the development of the tanning system and leather, which would be manageable for easy disposal (degradation under certain environmental conditions) after the intended usage of the product is an important need. In this present work, Gramineae Saccharum officinarum L. (Sugarcane Bagasse), a byproduct of the sugarcane industry is used as a tanning agent after converting the cellulose and hemicellulose content into dialdehyde polysaccharides from hydrolyzed bagasse (DAPB) by oxidation process. Leather from goatskins after conventional pre-tanning process (Soaking to Deliming), tanned by developed dialdehyde polysaccharides. The developed leather provided resistance to collagenase degradation, which reflects the tanning efficiency of dialdehyde polysaccharides. Additionally, tanned leather also provided reasonable mechanical strength. The leathers made from dialdehyde polysaccharides were observed to have properties comparable to conventional chrome tanned leathers. From hydrolyzed bagasse solution fungal strains are isolated and tested for the degradation of the crust dialdehyde polysaccharides tanned leather, where delimed pelt (untanned), chrome tanned, and vegetable tanned crust leathers were set as control. In comparison to delimed (untanned) pelt, the newly developed tanning system showed significant resistance to degradation. However, compared to chrome and vegetable tanned leathers, the dialdehyde polysaccharides tanned leather showed better biodegradation. The developed bagasse tanning system paves the way for a cradle to cradle approach in creating a circular economy and sustainable development in leather manufacture.

One of the long lasting problems associated with leather industry is to meet environmental standards for both liquid and solid wastes. Statistics show that one tonne of wet-salted hides/skins yields around 650 kg of solid waste. Among various wastes generated, trimmings for the most part have been underutilized. Collagen presents in trimmings waste are effectively used but hair goes unutilized or at the most as feed for boilers during gelatin manufacturing. Hence, newer technology is needed for complete and effective utilization of raw trimmings. In leather manufacture, formaldehyde condensates polymers are used as re-tanning agent to enhance the compaction of leather. However, these products are hard for biodegradation and also cause the release of free formaldehyde in leather, which is a known carcinogen. Here, there is a need for development of formaldehyde free re-tanning agent for eco-benign leather processing. In this work an attempt had been made to develop formaldehyde free biodegradable eco-benign re-tanning agent from raw trimming of tannery solid waste as a circular economy model. Alkaline (7.5%w/w NaOH) – hydrogen peroxide (10%w/w) pre-treatment followed by thermal hydrolysis at 100 °C for 5 h was an optimized method for effective hydrolysis of trimmings and the process of preparation of product results in the holistic utilization of raw trimmings. The developed product was characterized using Dynamic light scattering and FTIR techniques. The product prepared was further used in leather manufacture as a re-tanning agent and was found to impart multifunctional properties to leathers such as fullness, grain tightness and shade of dye brilliance. Product improves the mechanical strength characteristics of leather and also the exhaustion of post-tanning chemicals. SEM analysis shows that the experimental leather is more compact and flat than control. This novel strategy had not only solved the issue of solid waste but also resulted in a greener leather auxiliary leading to greener environment.

Background: Deformities and neuropathic chronic ulcers are the common features associated with leprosy-cured individuals that impact their quality of life and impair rehabilitation efforts. The challenging aspects for treatment of chronic wounds are the factors that inhibit healing. We reasoned that limited success of various therapeutic interventions could be due to the fact that leprosy-cured individual's physiology gets acclimatized to having a chronic wound that any therapeutic intervention is counterbalanced to maintain status quo at the wound site. Therefore, an alternative strategy would be to use biomaterials that gradually alter the wound site allowing the individual's physiology to participate in the healing process. Aims: Developing the human amnion (Amn)-derived biomaterial scaffolds and evaluating its use to heal chronic wounds in leprosy-cured but deformed persons (LCDPs). Materials and Methods: Using an enzymatic protocol, we have developed a rapid method to generate biomaterial scaffolds from discarded human Amn. A clinical trial on 26 LCDPs was performed with the biomaterial, and its wound-healing potential was then compared with LCDPs undergoing standard treatment procedure. Results: Biomaterial-based treatment of chronic wounds on LCDP displayed a higher efficiency in healing when compared to standard treatment. Conclusions: This study exemplifies that biomaterial-based treatment of leprosy-wounds offers an excellent affordable alternative for wound management. This study underlines the importance of involving both local wound environment and systemic effects for healing. In addition, we highlight wound healing as a necessity for successful rehabilitation and reintegration of leprosy-cured person into the society.

For the first time, GSK's solvent selection guide (SSG) has been explored for leather making from the view of sustainable manufacturing. A novel “Solvent Selection Tool” has been developed to identify sustainable non-aqueous media for leather making from the solvents listed in GSK's SSG. The developed solvent selection tool has been structured into four segments and each one has a particular screening criterion. Preliminary screening-I, based on the cumulative score of GSK's SSG, enabled the shortlisting of 41 solvents from 110. Screening-II, based on toxicity (LD50 value >5000 mg kg−1 of rat), has filtered the number of solvents down to 16 from 41. The effect of the selected 16 solvents on the hydrothermal stability of the skin matrix (screening-III) shows that 9 solvents, namely propylene carbonate, 1,2-propane diol, 2-butanol, ethyl lactate, tetraethylene glycol, ethyl acetate, ethanol and dimethyl carbonate, have no negative impact, whereas the other 7, namely glycerol, DMGMBE, diethylene glycol, propyl acetate, 1,3-propane diol, 1,4-butane diol and 2-propanol, have a negative impact on thermal stability. Propylene carbonate, dimethyl carbonate, ethanol and 2-butanol show superior tanning performance (screening-IV) in terms of mass transfer efficiency (>99% w/w), hydrothermal resistance (104 °C) and leather quality compared to the other selected solvents. The internal comparison results show that propylene carbonate is an ideal medium for a sustainable tanning process. The propylene carbonate based tanning process enjoys zero discharge of water/chromium(III), avoids the usage of fungicides in the tanning process and is ecologically acceptable.

Leather industry is forced to adopt green manufacturing options due to consumer awareness and statutory environmental stipulation norms. Conventional leather manufacture involves various physico-chemical treatment processes, leading to the generation of wastewater with high pollution load. Several alternative leather chemicals and in-process control measures have been developed to overcome the environmental issues. Till date, no such significant measures have been found out. Sustainable leather manufacture necessitates complete redefinition of the conventional leather making processes. Replacement of water with alternative sustainable carrier medium could be one of the possible redefined approaches. In this perspective, an attempt has been made to summarize the current status of different alternative carrier medium and its pros and cons with respect to leather manufacture. Solvent selection tool, usage of supercritical fluid and switchable solvents in different unit processes of leather manufacture are the green chemistry approaches to be employed in order to overcome the drawbacks associated with alternative carrier medium based leather manufacture. This review focuses on such possible green chemistry approaches, challenges and critical factors for usage of alternate sustainable carrier medium in leather industry.