Content: One of the well-explored alternatives to the lime – sulfide approach for dehairing and fibre opening is the enzymatic approach. In the approach, using a drum method, about 2.5 – 5.0%, on the soaked weight of the skin/hide, of the protease and amylase are sequentially employed, with each operation run for about 6 h. An extensive washing between the two steps required as the activity of one enzyme may be compromised in the presence of the other, especially during a long running of the drum. Though a combination approach, through the use of a bifunctional enzyme has been reported in the past for single step dehairing and fibre opening, this process is likely to have limited applications as there are reports that the storage stability of combination enzymes comprising of protease, amylase and lipase is low, which is generally circumvented by employing higher concentration of amylase and lipase over protease. The individual enzyme activities are also compromised in the presence of detergents and chelators. A similar scenario has also been observed in other industries such as food, laundry etc. The applicability of nanoparticlebased approach to immobilization of enzymes (individual) has been reported in areas such as catalysis and our earlier work immobilization of enzymes on iron oxide nanoparticles has been well received. In this paper, the immobilization of multiple enzymes on copper oxide nanoparticle surfaces is reported. The immobilization, the stability of the enzyme immobilized nanoparticles and the activity of the enzymes present in the immobilized system has been confirmed using various analytical techniques. The extended storage stability of the protease – amylase – nanoparticle system has been studied. A comparative study between protease – amylase combination (in the absence/presence of nanoparticles) indicated that in the absence of nanoparticles, the amylase activity was reduced, possibly due to denaturation of the amylase by the protease. The mechanism by which copper oxide nanoparticles prevent the denaturation of amylase has been studied through computational methods. From the leather processing point of view, the use of protease – amylase – nanoparticle system for combined dehairing and fibre opening has been established and the intact nature of the collagen fibres confirmed through histopathological studies. A comparison between lime-sulfide, protease followed by amylase, protease-amylase-nanoparticle systems for dehairing – fibre opening has been made and the effectivity of the nanoparticle immobilization demonstrated. Take-Away: - A transition from chemical to bioprocessing - Better acceptability of enzymatic approaches as known lacunae are overcome - Sustainable beam house operations

Content: A copolymer has been synthesized from leather waste and monomer and its application has been studied for improved exhaustion in tanning and post-tanning processes. After synthesizing, the product has been analyzed and found to have particle size of 810 nm, pH of 4.0, relative viscosity of 0.8872 cp, polydispersity index (Mw/Mn) of 0.555 and percent solid as 23%. The weakly anionic character of the copolymer is supported by zeta potential of –0.0403 mV. The stability of the particle was also studied using TGA, DSC. Functional groups of the polymer was analyzed by FT-IR which revealed the presence of carboxylic acid, amide I & II, hydroxyl groups and ester groups in the product. The product can be used for increasing exhaustion and leather-properties in chrome tanning and post-tanning processes. It improves belly filling, provides fullness, softness and dye exhaustion in post-tanning process. It also shows better fullness and body in chrome tanning processes. The color properties found to be better and strength properties were comparable in experimental leather as compared to conventionally produced leather. This product can be applicable for manufacturing different types of leather where fullness and tightness are necessary. The present process helps in mitigating pollution problem of liquid and solid wastes of leather industry. A cost benefit analysis shows that the process is feasible for up-scaling. Take-Away: Synthesis of Co-Polymer from Leather Waste Application of Co-polymer as retanning agent Improved Exhaustion & Organoleptic Properties of leather

Content: The wastewater after the fatliquoring process contains the surfactants, neutral salts and unspent or unbound oil. This is predominantly attributed to the manner in which fatliquors are prepared. The oil in water emulsions (fatliquors) are prepared through chemical modification of oils along with surface active agents that would enhance the dispersion of oil in water. The discharged chemical compounds from the post tanning process are likely to exist as persistent organics in the soil. In this paper, an ambitious effort to take forward the successful lessons from other sectors such as healthcare is presented. The use of liposomes as oil carriers has been envisaged. For this, the lacunae associated with liposomal carriers such as stability, encapsulation efficiency, the release of payload under desired conditions etc. has been addressed. The study focuses on stabilizing the liposomes and the triggered delivery under the drum pH conditions. A liposomes -biopolymer composite based on Egg Phosphatidyl Choline and Pectin encapsulating oil, has been prepared. Using spectroscopic and colorimetric techniques the presence of biopolymer in the composite, encapsulation of oil and stability over a range of pH conditions has been investigated. The biopolymer influences the stability and oil encapsulation efficiency of the composite in a concentration-dependent manner. To understand the release of oil in a pH dependent manner, the oil was substituted with a model dye and its release under a narrow pH span was observed, indicating that the oil could be released to fibers by modulating the pH. I nitial studies relating to the potential of this product as a possible fatliquor is encouraging. Take-Away: A stabilized liposomal systems encapsulating oil as a delivery vehicle to deliver its contents under the triggered pH conditions is described. Biopolymer, induced stability and ensures the oil encapsulation in the bilayer region for the composite vesicles. The work initiates a step towards developing fatliquors based on biodegradable materials, avoiding the emulsifiers and conventional route to make oil in water emulsions.

Content: The value chain of leather is complex and originates from the animal husbandry system to meat processing, pre tanning, tanning, post tanning and product manufacturing processing. The imbibed properties of the material gained from the environmental conditions under which the animal grew to the range of human skills and processing chemicals determines how best the leather products meet the customer desires. The customer desire for feel and handle is ultimately traced back to the origin of the animal itself. Leather thus is a unique product whose properties such as visco-elasticity, breathability etc. remained unmatched by synthetics. Industrialization activities, reduced farming, the vegan culture all have contributed to reduced availability of hides and skins for meeting the quantity of leather required for various end products. This in essence contributed to the growth of a new market for synthetics, wherein the manmade fabrics tried to reproduce all the features of leather, synthetically. Commercially, these products came to be known through various names such as leatherette, faux leather, vegan leather, PU leather, pleather etc. Advancement in material science led to a range of products and manufacturing methods has today ensured that conventional identification techniques such as rough edges, imperfect surfaces, wrinkle test, water absorption, burnability, uneven stitch holes, structure retention, smell, grain pattern can no longer be used to distinguish between leather and similar artificial products. Advancement in technology for the manufacture of various types of leather like materials has made it difficult to identify genuine leather from other leather like materials. With leather like materials meeting most of the conventional methods of identifying genuine leather there is today a need for a new methodology for identifying genuine leather. This paper addresses to a study of a statistically relevant number of samples of leather and non-leather materials through a range of iterative instrumental techniques leading to the establishment of a protocol for identification of genuine leather. The methodology starts with the FTIR-ATR based (non-destructive) identification of signature bands of collagen – the amide I, II and III. After the first level screening, iterative analysis of samples that have the amide bands matching with that of collagen would be screened through techniques such as hydroxyproline estimation, thermogravimetric analysis, fibre structure assessment etc. The paper would report the results, the positives and negatives associated with the first level screening for genuine leather using FTIR. Take-Away: 1. A method for identifying genuine leather. 2. Value addition to leather by way of facile identification. 3. Customer satisfaction.

Content: Beamhouse area is an important step in leather technology, either in the final quality of the leather or in the contribution to the contamination of effluents. In unhairing process, the use of enzymes as sulphide assistants can reduce sulfhidric gas emissions to reach permitted levels for health. The characterization of enzymatic extracts allows controlling the proteolysis mechanism so that its action does not attack the reticular structure. A new fungal enzyme extracts were applied on submerged bovine skin in the soaking and unhairing steps. Fungal strains were isolated from alkaline soils of coast of Buenos Aires province and enzymatic extracts (EE) were obtained by submerged culture with bovine hair waste from hair-saving unhairing process as inducer in the production of keratinolytic enzymes. This activity was determined by quantitative test and the most productive strains were selected: Clonostachys rosea (CR), Emericellopsis minima (EM), Paecilomyces lilacinus (PL), Penicillium sp (Psp), Fusarium oxysporum (FO), Acremonium sp (A) and an unidentified filamentous fungus strain with sterile yellow mycelium (SYM). EE were tested at laboratory scale on submerged bovine skin with biocide 0,2% w/w wet skin, anionic 0,1% and non-ionic 0,5% tensioactives in soaking and unhairing respectively and incubated 48 h at 37°C in shaking thermostatic bath. Controls were tested in the same conditions without EE. Morphological changes in the skin were observed by scanning electron microscopy (SEM). Pieces of bovine skin were fixed, post-fixed in formaldehyde 4% and dehydrated in alcohol solutions, treated by critical point drying, metalized and analyzed in SEM. It was observed with FO, EM and A extracts empty hair follicles, absence of epidermis, papillary layer of dermis exposed, hairs enclosed by detached hair follicle sheaths and collagen fibers without characteristic patterns. With PL and SYM EE some hairs were detached while Psp and CR EE did not produce changes. In control samples epidermis and hair without modification were observed. In the quantitative test, keratinolytic activities increased in the following order: A<PL<Psp<CR<FO<SYM. Submerged culture with keratin as inductor produced keratinolytic enzymes useful for unhairing step. Fusarium oxysporum extract showed the greatest effect on the skin, thus the relationship between keratinolytic activity and depilatory effect was found. However, it is necessary to find the optimal conditions to avoid the damage of collagen and enable its application as a sustainable technology. Take-Away: A new fungal isolates applicated to bovine skin in beamhouse processes

Content: In the leather industry, the shaved wastes after the wet blue phase, which are exposed by the shaving process, are one of the substances that cause environmental pollution for the leather industry. Most of the time, these wastes can be buried and may cause serious environmental pollution. In this study, wet blue shaved wastes to be mineralized to chromium and so prevented oxidise to Cr (VI) by using oyster mushrooms (Pleurotus ostreatus) .Wet blue shaved wastes were mixed with 0.5%, 1%, 1.5% and 2% doses into the growth medium. After the oyster mushroom growth, the consuming of chromium from the growth media and chromium content that uptaken by the mushroom were investigated with in House method / ICP-MS. Take-Away: -Oyster mushroom degrade the waste -Oyster mushroom can uptake chromium -Oyster mushroom can grow medium where contens chromium

Content: Leather goods are noble and sustainable but leather production may bear a potential for pollution. During leather manufacture high amounts of chromium shavings, wet by-products of the leather industry, are produced worldwide. Due to their chromium content they are disposed in landfill sites worldwide leading to long lasting environmental problems. They are stable towards temperatures of up to 110 °C and enzymatic degradation, preventing anaerobic digestion in a biogas plant. This stability is due to the three-dimensional native structure, typical for collagen, and additional chemical cross-links between the collagen fibers achieved by Cr3+ salts in the tanning step in tanneries. Therefore, hitherto chromium shavings are not utilized industrially to produce biogas. In order to ease enzymatic degradation, necessary to produce biogas, a previous denaturation of the native structure has to be carried out. Otherwise, the generation of biogas is hindered. In our projects, shavings were pre-treated thermally and mechanically by extrusion and hydrothermal methods. In previous works, we studied intensively the use of these shavings to produce biogas in batch scale and significant improvement was reached when using pre-treated shavings. In this work, a scale-up of the process was performed in a continuous reactor using pre-treated and untreated shavings to examine the feasibility of the considered method. Measuring different parameters along the anaerobic digestion, namely organic matter and volatile fatty acids content, it was possible to show that a higher loading rate can be used when feeding the reactor with pre-treated shavings instead of untreated shavings, which means a more economical process in an industrial scenario. Take-Away: The use of a pre-treatment improves the biogas production from chromium shavings

Content: Application of biocatalyst becomes an imperative due to their eco-friendly advantages. Enzymes in pretanning for unhairing, fiber opening, defleshing and bating are well reported and practiced. However, the role of enzymes as a chemical aids is less explored and consider as a secondary applications. Leather enzymes are known for its hydrolytic behavior which makes it more suitable for pretanning operations. However, typical chemical exhaustive aids acts as a vehicle for the diffusion of chemicals, whereas enzymes aids in the splitting of fibers which facilitate the diffusion of chemicals and create more functional sites for the tanning and post tanning chemicals to interact. In this research, pickled pelts are treated with acid protease and subsequently tanned using chrome tanning agent. Enzymatic treated pelts resulted in better uptake of chromium as compared to conventionally processed leathers. Similarly, after neutralization, chrome tanned leathers are treated with alkaline protease to conventional post tanning has been carried out. Enzymatic treated wet blue leathers showed high uptake of post tanning chemical, uniform dyeing and reduction in the pollution load. From the preliminary research, an interesting finding has augmented that application of enzymes at an optimized concentration, temperature, pH and time would lead to better uptake of chrome which reduces the pollution and minimization pollution load in post tanning. This study, emphasize on the application of enzymes in tanning and post tanning for higher diffusion of chemicals. Take-Away: 1. Replacement of conventional exhaustive aids using biocatalyst 2. Higher exhaustion rate of tanning and post tanning chemicals 3. Futuristic technology for sustainable leather manufacture

Content: The wastewater of leather industry contains pollution loads which includes anionic contaminants such as chloride, sulfate and phosphate. Different treatment technologies for tannery wastewater have been investigated. Adsorption is a promising technique due to its greater selectivity, simple operation, faster regeneration kinetics and high uptake capacity even at trace levels. In the present study, Mg-Al and Zn-Al Layered Double Hydroxides were synthesized by the co-precipitation method at variable pH through a semi-batch system. The prepared material was characterized by XRD, BET surface area determination, TGDTA and FTIR. The chloride, sulfate and phosphate adsorption properties onto Mg-Al and Zn-Al Layered Double Hydroxides from aqueous solutions were evaluated. The adsorption experiments of chloride, sulfate and phosphate were investigated through batch studies at initial concentrations of 100 mg/L of these anions as NaCl, K2SO4 and KH2PO4, respectively. The experiments were carried out separately for each anionic specie by mixing 10 ml of solution with 1 g/L of adsorbent for 5 h. Mixing was performed on a thermostatic shaker at 200 rpm and at room temperature (25 °C). The effect of co-existing anions on the adsorption capacity were also analyzed. After ion adsorption, chloride, sulfate and phosphate concentrations were measured by ion chromatography. The results showed a removal ratio for Mg-Al Layered Double Hydroxide of 24% and 51% for sulfate and phosphate, respectively, while chloride was not removed from the solution. For the adsorbent Zn-Al Layered Double Hydroxide, the removal ratio of sulfate, phosphate and chloride reached 12.76 %, 69.07 % and 6.34%, respectively. Take-Away: Both adsorbents exhibited a satisfactory removal ratio of phosphate. Therefore, Mg–Al and Zn–Al LDHs can be used as effective adsorbents for phosphate removal from industrial wastewaters.

Content: Leather is a kind of natural biomass composite material which is made of animal skin as material by a series of chemical and physical processing. Its main structure is Collagen fibers of three-dimensional network structure. As we all know sheep leather always exist a common problem with low strength, while the strength of leather depended on the woven degree of collagen fibers. Through the past decades, many methods have been tried to improve the properties of sheep leather. The most commonly used methods are retanning. However, the strength enhancement of sheep leather is extremely limited by retanning, although the fullness and softness may be improved. In this study, a new type of multi-epoxy reinforcement agent (IGE) and IGE with the synergistic effect of polyamine (IGE-PA) were used to enhance the strength of sheep leather in tanning and fatliquoring process. Comparing with chromium tanned leather, it was found that under the optimized conditions (dosage: 10%, pH: 8, Temperature: 35℃ for penetration and 45℃ for fixation, tanning time: 10 h) with IGE as the main tanning agent, the tearing strength was increased 56.8%. While when the polyamine as the synergetic agent for IGE, the tearing strength was significantly increased 87.9%. While IGE and IGE-PA were used in fatliquoring process, it has significant reinforcement effect for tetrakis hydroxymethyl phosphonium (THP) salt tanned leather. It was found that under the optimized conditions (Dosage: 2.5%, pH: 7-8, Temperature: 50℃, Time: 2h) with IGE in fatliquoring process, the tear strength was increased 50.24%, while the IGE-PA was used, the tear strength was increased 64.3%. Furthermore, TGA results showed that decomposition temperatures of IGE and IGE-PA enhanced leather were all higher than traditional chromium tanned leather. In addition, SEM results showed that IGE and IGE-PA enhanced leather obtained better opened-up fiber structure. Take-Away: 1. A new type of multi-epoxy tanning agent (IGE) has reinforcement effect for sheep leather especially in tear strength. 2. IGE with the synergistic effect of polyamine (IGE-PA) were used in tanning process, which has a significant enhancement for the sheep leather. 3. IGE and IGE-PA can be also used in fatliquoring process to enhance the strength of sheep leather.