Due to the impact of the Covid-19 pandemic, the usage of numerous protective face masks has faced an explosion in demand around the world. Therefore, the need to reduce the environmental pollution caused by disposable single-use face masks has become vital. Recently, alternative raw material solutions have been discussed to eliminate the consumption of single-use plastics. Within this research, gelatin nanofibers were fabricated via centrifugal spinning technique, and filtration media were investigated in terms of air permeability and filtration efficiency. In addition, morphological properties were examined with scanning electron microscopy. Fabricated fibers have a changing average diameter range from 232 to 778 nm, and targeted 95% filtration efficiency was achieved in several compositions. It was proven that biodegradable gelatin nanofibers could be a sustainable alternative for disposable N95 respiratory filters.

This study was conducted to determine the effect of gelatin reology on mechanical, physical and morphological properties of gelatin-based edible films. The aim of this study was to better understand the variation of viscosity on the structural behaviour of gelatin-based films in the presence of glycerol and sorbitol plasticizers. Gelatin-based films were casted by using gelatins of different viscosities as 2.5, 3.0 and 3.5 centipoise with plasticisers as glycerol and sorbitol. Finally, the physical, mechanical and morphological properties of the films were investigated via pH, thickness, tensile strength and elongation, fourier transform infrared spectroscopy and scanning electron microscopy. As a result of the study, it was observed that a durable film structure could be obtained with gelatin viscosity at 3 centipoise. Furthermore 5.5% gelatin, 0.1% glycerol and 0.4% sorbitol concentration were found as the most suitable formulation for gelatin based film structure with Tukey Test. The results suggest that gelatin-plastisizer combinations can be an excellent source of biobased packaging material with further investigations.

Environmental consciousness and constraints in developed societies over the past 20 years have brought about a dramatic impact on tannery operations worldwide. Leather industry has been categorized as one of the most polluting industries, and it spoils the continuity of environmental rhythm because of the generation of liquid, solid and gaseous wastes and also by-products. Solid organic wastes involving untanned (trimmings, fleshings and splits) and tanned (trimmings, splits and shavings) wastes and by-products depending on their proteinic character have an advantage of recovery and reuse potentials instead of disposal to landfills in terms of environmental sustainability. These solid wastes and by-products are not properly treated and disposed of; hence, they can cause environmental damages to soil and groundwater as well as release emissions and poisonous greenhouse gases into the atmosphere. Valorization of these tannery solid wastes and by-products with different methods and processes is highly important for the perspective of eco-benignity and with respect to converting into new value-added products. This chapter focuses on the evaluation of the tannery solid wastes and by-products by partial and total denaturation and hydrolyzation. This paper also examines in general the specifications, production techniques and applications of collagen peptides in several industries.

A bioretanning agent was developed as an alternative to conventional synthetic retanning agents to pave the way for sustainability in the leather industry. Tanned solid waste shavings obtained from leather processing was utilized to produce a proteinic sub-structure for constitution building block of the bioretanning agent's backbone. The protein hydrolyzates were acquired with different molecular weights and the hybrid biopolymers were obtained by grafting the hydrolyzates with acrylic acids (AAc) and acrylamides (AAm). To evaluate the properties imparted by the designed bioretanning agent, it was incorporated into the leather in the retanning processes and compared to the control samples fabricated with conventional procedures. Penetration of hybrid biopolymer into the matrix for retanning was achieved easily, and using low and high molecular weight biopolymers have been recorded by 20% and 23% of improvement on the mechanical performance of the leather samples, respectively. The ratio of the hydrolyzate and AAm/AAc was found to be fitted at 1:2 for both. Furthermore, as per the evaluation of the leathers retanned by novel biopolymer, the results were promising in terms of technical viability and revealed that the biopolymer usage could enhance the mechanical performance of the leather while benefiting from the waste-to-wealth approach.

In the present study, the effect of different ratios of GelMA concentration has been exhibited for wound dressing implementation by the electrospinning method using a new polymer combination of Gelatin methacrylate (GelMA)/Polycaprolactone (PCL)/Chitosan (CS). The nanofiber composites were fabricated due to their biocompatible, biodegradable, improved mechanical strength, low degradation rate, and hydrophilic nature to develop cell-mimicking, cell adhesion, proliferation, and differentiation. Different concentrations of GelMA were added to the PCL/CS solution as 5, 10, and 20 wt%, respectively, in the formic acid/acetic acid (7:3) solution. A photoinitiator was added to the solution for photo-crosslinking of GelMA. The influence of different solution concentrations (5, 10, and 20 wt%) on the structure’s nanofiber production and fiber morphology was examined. SEM micrographs revealed that varied GelMA concentrations resulted in suitable and stable nanofiber composites. The average diameter of nanofiber composites grows as the GelMA concentration rises. FTIR, DSC, tensile test, degradation, and swelling test were evaluated. The results demonstrated that high mechanical strength, hydrophilic properties, and a slow degradation rate were observed with the presence and increment of GelMA concentration within the nanofiber composites. The antibacterial potential of GelMA/PCL/CS nanofiber composites was evaluated against P. aeruginosa and S. aureus using a disc diffusion assay. In vitro cell culture research was conducted by seeding NIH 3T3 fibroblast cells on nanofiber composites, proving these cells’ high cell proliferation rate, viability, and adhesion. 10 wt% GelMA-based nanofiber composites were found to have great potential for wound dressing applications.

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The leather industry, due to its way of using chemicals during treatment and releasing them back to the environment makes it one of the hazardous sectors. It is not only releasing the chemicals also during the process precious biomass such as collagen and keratin discarded as waste. In this study, bovine hair which occurs during the treatments of the bovine leather process is supplied as waste and converted to superabsorbent hydrogel via grafting of keratin with monomers (Acrylic Acid (AA), Acrylamide (AAm)) in the presence of N, N'-methylene bisacrylamide (NMBA) used as a crosslinking agent and ammonium persulfate (APS) as an initiator. Keratin is selected to enhance the biocompatibility of the hydrogel. Thus, different keratin/monomer ratios, crosslinking agents, and initiator amounts were accepted as variables, and reaction conditions were optimized to achieve the highest swelling capacity. Synthesized hydrogels were chemically, morphologically, and thermally characterized via Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), differential scanning calorimeter (DSC), and thermal gravimetric analyzer (TGA). FTIR, DSC, and TGA results confirmed the grafted structure. The maximum swelling ratio was recorded at pH 9, at the end of 48 hours as 1791%. Sponge-like hydrogels were successfully obtained, and waste keratin is successfully valorized by means of hydrogels which can be used in high-value-added areas.