Chrome-free leather processing based on amine pendant metal-organic frameworks and dialdehyde with enhanced dye affinity.

To overcome the stringent regulations in the usage of chromium salts and dye-rich effluent let out by the tanning industry, a sustainable way of leather processing has been demonstrated utilizing amine pendant metal-organic frameworks (MOF) UiO-66-NH along with glyoxal. It was found that an offer of 8% (w/w) MOF along with 6% (w/w) glyoxal increased the shrinkage temperature of the leathers to 89 ± 2 °C with exhaustion of MOF up to 84.3 ± 1.

Extraction of dermatan sulfate using ionic liquid-assisted enzymatic digestion: An efficient approach.

Dermatan sulfate is one of the major glycosaminoglycan (GAG) present in the animal hides, which is a waste/byproduct from meat industry. Efficient utilization of these meat industry wastes is garnering attention because these wastes render a possibility for their conversion into useful products. With the increased concerns over health, various initiatives have been developed to permit more efficient utilization of these by-products and thereby directly impacting environmental sustainability.

Research advances in the fabrication of biosafety and functional leather: A way-forward for effective management of COVID-19 outbreak.

With the recent events following the pandemic COVID-19, global awareness about the use of biosafety materials has been in raise. Leather industry being a major commodity-driven sector, its role in addressing the issues concerning the safe use of leather products has become inevitable for the sustainability of the industry. A significant number of researches have been conducted to fabricate bio-safe leather by incorporating different types of antimicrobial agents during leather manufacturing.

Melamine-Based Polymeric Crosslinker for Cleaner Leather Production.

To augment sustainable tanning, less chrome input, high functional quality leather processed via no restricted substance in processing, and ease to treat the inevitable protein waste generated are the key challenge, and currently, they have become the active part of leather research. Our work covers the synthesis of a formaldehyde-free chromium-incorporated polymeric tanning agent (FF-CIPTA) and its application in a reformed leather processing route which ensures near zero discharge of chromium containing solid waste. The preliminary characterization of FF-CIPTA reveals that the developed product is stable up to pH 5.

Non-aqueous green solvents improve alpha-amylase induced fiber opening in leather processing.

Severe water deficit and highly polluting effluent generation from leather industries have constantly been pressurizing the tanners to adopt cleaner leather processing systems. The present study aims to minimize the use of water by substituting it with non-aqueous green solvents and also to enhance the enzyme action in alpha-amylase based fiber opening process. The activity of alpha-amylase in select non-aqueous green solvents namely, heptane, polyethylene glycol 200 and propylene glycol is considerably higher by 62, 38 and 31% than in water, respectively.

Chromium containing leather trimmings valorization: Sustainable sound absorber from collagen hydrolysate intercalated electrospun nanofibers.

Developing value-added material from industrial waste is one of the sustainable ways of recycling solid waste produced from the leather industry. Noise which makes a considerable negative impact in the day to day life of people needs immediate attention where the sound absorbers play a vital role. Nanofibers can be used as sound absorbers due to their properties like porosity and high surface area.

Chromium-catechin complex, synthesis and toxicity check using bacterial models.

Chromium-catechin complex was synthesized by reacting [Cr(HO)] (hexa-aqua) with catechin as a ligand. Toxicity studies were carried out for the complex using bacterial models for safer application of this complex in the future as a drug. Chromium-catechin complex was characterized using ESI Mass spectrometry, electronic spectroscopy, FT-IR spectroscopy and cyclic voltammetry.

Leather solid waste: An eco-benign raw material for leather chemical preparation - A circular economy example.

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.

Adsorption of Proteins on Dual Loaded Silica Nanocapsules.

The design of nanocarriers containing hydrophobic and hydrophilic compounds represents a powerful tool for cocktail delivery. Water-in-oil-in-water emulsions constitute an attractive approach, as they offer dual encapsulation and provide a template for the constitution of a capsule. A limitation in the preparation of nano double emulsions is their instability resulting from high curvature radii.

Stability of collagen in ionic liquids: Ion specific Hofmeister series effect.

In protein-ionic liquids (ILs) interactions, anions play an important role. In this work, imidazolium-based ILs (IILs) with varying anions namely dicyanamide (DCA), hydrogen sulfate (HS), dimethyl phosphate (DP), acetate (A), sulfate (S) and dihydrogen phosphate (DHP) have been chosen with the aim of understanding the role of anions in bringing about the destabilization effect on collagen based on the kosmotropicity and chaotropicity of ions. Imidazolium-based ILs destabilized the triple helical structure of collagen, thereby proving as strong denaturants for collagen and this was confirmed by various spectroscopic techniques viz.

Inorganic apatite nanomaterial: Modified surface phenomena and its role in developing collagen based polymeric bio-composite (Coll-PLGA/HAp) for biological applications.

Nano sized bio-composites containing inorganic particles conjugated with polymer and protein are considered as potential material for tissue engineering systems like bone repair and advanced drug delivery. More specifically, hydroxyapatite (HAp), a well known as the strong bioactive material has limitations on reactivity towards biological systems. Thus, this work explains the interaction betweena natural biomaterial Collagen and poly (lactide co-glycolide)-Hydroxyapatite (HAp) composite.

A logical and sustainable approach towards bamboo pulp bleaching using xylanase from Aspergillus nidulans.

Driven by the environmental benefits that bio-bleaching could bring, the interest in xylanase has received enormous attention and hence, the search of xylanase with properties like no cellulase activity, function at elevated temperatures and pH continues. The present study reports the production of extracellular xylanase from Aspergillus nidulans using waste agro-residues as substrate. The optimum temperature (60 °C) and pH (9.

Is Cr(III) toxic to bacteria: toxicity studies using Bacillus subtilis and Escherichia coli as model organism.

The objective of this work is to detect the mode of damage caused by Cr(III), one of the widely used industrial pollutant on Bacillus subtilis-industrial strain 168 and Escherichia coli MTCC 40. Bioassays are very sensitive, precise, economical and rapid for detecting early stages of pollution. The detrimental effect of trivalent chromium becomes clear from the growth profile and growth inhibition studies.

Differential behavior of native and denatured collagen in the presence of alcoholic solvents: A gateway to instant structural analysis.

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.

Selective toxicity of Catechin-a natural flavonoid towards bacteria.

Catechin is a plant polyphenol composed of epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG) as diastereoisomers. Among the various classes of flavonoids, catechin was found to be the most powerful free radical scavenger, scavenging the reactive oxygen species (ROS) generated due to oxidative damage with antibacterial and anti-inflammatory activity. The toxicity of catechin towards bacteria was studied using gram-positive bacteria (B.

Does L to D-amino acid substitution trigger helix→sheet conformations in collagen like peptides adsorbed to surfaces?

The present work reports on the structural order, self assembling behaviour and the role in adsorption to hydrophilic or hydrophobic solid surfaces of modified sequence from the triple helical peptide model of the collagenase cleavage site in type I collagen (Uniprot accession number P02452 residues from 935 to 970) using (D)Ala and (D)Ile substitutions as given in the models below: Model-1: GSOGADGPAGAOGTOGPQGIAGQRGVV GLOGQRGER. Model-2: GSOGADGP(D)AGAOGTOGPQGIAGQRGVVGLOGQRGER. Model-3: GSOGADGPAGAOGTOGPQG(D)IAGQRGVVGLOGQRGER.

Dual utility of a novel, copper enhanced laccase from Trichoderma aureoviridae.

Ever since the ability of laccase to oxidize non-phenolic lignin models was described, the oxidative degradation reactions catalyzed by laccase have been widely studied for paper pulp production or detoxification of aromatic pollutants. The viability of developing eco-friendly, laccase aided industrial processes has been explored. Here, we report the isolation and screening of fungi to explore their lignolytic ability on solid media using various substrates as indicators.

Go natural and smarter: fenugreek as a hydration designer of collagen based biomaterials.

Collagen-based biomaterials have received considerable attention for smarter biomedical applications due to their inherent superior mechano-biological properties. However, accumulating evidence suggests that water, as a probe liquid bound in collagen, might be investigated to explore the influence of additives on the static and dynamic solvation behavior of collagen. The structure and dynamics of water near the surface/interface of collagen-fenugreek composites were demonstrated via circular dichroic spectroscopy, thermoporometry and impedimetric measurements to enlighten about the configuration-function relationship of collagen.

Effect of aqueous ethanol on the triple helical structure of collagen.

Collagen, the most abundant protein in mammals, is widely used for making biomaterials. Recently, organic solvents have been used to fabricate collagen-based biomaterials for biological applications. It is therefore necessary to understand the behavior of collagen in the presence of organic solvents at low (≤50%, v/v) and high (≥90%, v/v) concentrations.

Stabilization of collagen through bioconversion: An insight in protein-protein interaction.

Collagen is a natural protein, which is used as a vital biomaterial in tissue engineering. The major concern about native collagen is lack of its thermal stability and weak resistance to proteolytic degradation. In this scenario, the crosslinking compounds used for stabilization of collagen are mostly of chemical nature and exhibit toxicity.

Elucidation of hydration dynamics of locust bean gum-collagen composites by impedance and thermoporometry.

The intricacy of the different parameters involved in the hydration dynamics of collagen influences its performance as biomaterials. This work presents the molecular motions of collagen originating from the solvents and locust bean gum (LBG), which reveal the changes in solvation dynamics of the biopolymers affecting the surface as well as interfacial properties. Water, as a probe liquid bound in collagen has been investigated using a combination of thermoporometry, ATR-FTIR, circular dichroic spectroscopy, dielectric spectroscopy and SEM to explore the influence of LBG on collagen with respect to static and dynamic behaviour.

Studies on the chemico-biological characteristics of bilirubin binding with collagen.

The clinical impact of bilirubin on collagen is investigated using various physical, chemical and biological methods. Thermo gravimetric analysis and differential scanning analysis of collagen-bilirubin complex matrices indicate that crosslinking does not alter their thermal behavior of collagen. The polydispersity of collagen-bilirubin complex increases in the reacting medium suggesting that there is an increase in the number of interacting points between them.

Influence of PCL on the material properties of collagen based biocomposites and in vitro evaluation of drug release.

Formulation of biodegradable collagen-poly-ε-caprolactone (PCL) based biomaterials for the sustained release of insulin is the main objective of the present work. PCL has been employed to modulate the physico-chemical behavior of collagen to control the drug release. Designed formulations were employed to statistically optimize insulin release parameter profile at different collagen to PCL molar ratios.

Investigation on interaction of tannic acid with type I collagen and its effect on thermal, enzymatic, and conformational stability for tissue engineering applications.

Collagen is an essential component of tissues, which is the most abundant component in extracellular matrix and highly conserved across the animal kingdom. It can assemble into fiber and play an essential role in cell adhesion and growth and could be extremely useful in tissue engineering. In this study, the effect of tannic acid (TA) on the thermal, enzymatic and conformational stability of type I collagen has been investigated for the development of collagen-based biomaterials.