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This article explores a novel method for enhancing the mechanical properties of epoxy resin composites by incorporating carbonized chicken feathers as a filler material. The fabrication process involves carbonizing chicken feathers at 600°C and incorporating 5-10 wt% of the fillers into an epoxy matrix. The composites showed enhanced mechanical properties and samples containing 10 wt% filler exhibit the best properties. The performance corresponds to 49% increase in tensile strength, 16% rise in Young's modulus, 40% improvement in flexural modulus, and 57% in flexural strength. X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy were employed to characterize the filler. This characterization provides valuable insights into the structure and chemical composition of the pulverized carbonized chicken feathers that contributed to the attained improvement in composites' properties. Microstructural examination of the developed composite under scanning electron microscope also provides insights into matrix-filler interface and dispersion of the fillers within the composite matrix. The study not only highlights the unique combination of carbonized feathers' inherent strength and compatibility with the epoxy matrix but also underscores the eco-friendly nature of utilizing agricultural waste. The findings suggest promising applications in industries demanding lightweight, high-strength materials, which can contribute to sustainable engineering solutions. [ABSTRACT FROM AUTHOR]

Protein gels prepared by keratin extracted from chicken feathers show potential applications as engineered materials. Feathers are an abundant waste material, whose principal component is keratin, which may have gelling properties not yet sufficiently studied so far which are strongly dependent on the extraction method adopted. The aim of the study is to explore the properties of gels obtained through mercaptoethanol extraction and dialysis process and to evaluate their structural characteristics. The keratin hydrogels were characterized with Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy through which it was possible to identify the secondary structure of the protein on hydrated and dry gel. Moreover, the morphological analysis by scanning electron microscopy (SEM) combined with the rheological analysis showed how the consistency of the gels is maintained on a wide range of loads and frequencies. Furthermore, the biocompatibility of the gels was investigated for the release of subcutaneous drugs using curcumin, an antioxidant polyphenol compound. The fastest release was obtained at pH 7.4, corresponding to physiological conditions. [ABSTRACT FROM AUTHOR]

The present study aimed at converting meat industry waste, particularly waste bones and chicken feathers, into biochar to recycle valuable nutrients present in it, which ultimately become part of the municipal waste. The bone biochar (BB) and feathers biochar (FB) were prepared at 550 °C, and their potential was evaluated as an organic amendment for the growth of sunflower. The ash content (AC) and fixed carbon (FC) improved significantly in prepared biochars as compared to raw feedstock. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analyses signaled the occurrence of various functional groups viz. amide group and hydroxyapatite, porosity, and multiple nutrients. Application of BB and FB in potted soil alone as well as in composites (1:1, 1:2, 2:1) at 1%, 3%, and 5% (w/w) and synthetic fertilizer significantly increased soil pH, electrical conductivity (ECe), organic matter (OM) and water holding capacity (WHC), while reducing the bulk density (BD). The growth of plants grown in soil treated with a 2:1 composite of feathers and bone biochar at 5% application rate showed significantly greater differences in plant height, total chlorophyll content, and plant dry weight than the control but was comparable to growth with chemical fertilizer, rendering it a potential alternative to chemical-based synthetic fertilizer. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare the effectiveness of raw chicken feathers (RCFs), NaOH and ethylenediamine-modified chicken feathers (MCFs), and xanthate-modified chicken feathers (XMCFs), treated with both NaOH, ethylenediamine, and carbon disulfide. The physicochemical characteristics of the biosorbents were analyzed using attenuated total reflection Fourier transform infrared spectrophotometry (ATR-FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), adsorption of N2 at −196°C and point of zero charge determination (pHpzc). The biosorption of Cr(VI) using MCFs and XMCFs was evaluated through various parameters, namely, pH, biosorbent amount, and contact time in batch experiments. The results showed a significant increase in the biosorption capacities of MCFs (90.90 mg/g) and XMCFs (100 mg/g) compared to RCFs (52.63 mg/g). The batch adsorption experiments indicated that the optimal conditions for biosorption were pH 2.0, with an equilibrium contact time of 90 min for RCFs, and 60 min for both MCFs and XMCFs. The optimal biosorbent concentrations were 16 g L−1 for RCFs and 12 g L−1 for both MCFs and XMCFs. The biosorption behavior was well described by the Langmuir isotherm and pseudo-second-order kinetic models. The thermodynamic parameters indicated that the biosorption of Cr(VI) onto the biosorbents was a spontaneous and endothermic process. Desorption analysis was carried out using a 0.1 M NaOH solution. [ABSTRACT FROM AUTHOR]

In this paper glass/chicken feathers reinforced epoxy composite and glass/chicken feathers reinforced polyester composite was prepared in the laboratory at different percentage of the glass and chicken feathers. Tensile properties, flexural properties, shore hardness and impact strength of the glass/chicken feathers reinforced epoxy composite and glass/chicken feathers reinforced polyester composite was studied experimentally and compared at different percentage of the glass and chicken feathers. The composite will be used in humid and corrosive environment; therefore, water absorption and acid corrosion test were performed. To understand the degradation behaviour of the composite, soil test was performed. Scanning electron microscopy analysis was carried out to find the fracture and interfacial characteristics of the composites after tensile test. This hybrid composite can be used in automobile, structural and defense sector. [ABSTRACT FROM AUTHOR]

The extraction of keratin from chicken feathers is of research interest due to the beneficiation of biomass. This study investigates the impact of the keratin hydrolysate obtained using four different methods. There are two different chemical extraction methods, CH1 and CH2, and two enzymatic hydrolyses, EH1 and EH2. The investigation includes the characterization and analysis using different types of equipment for different applications. The keratin hydrolysates formed were all characterized using FTIR, TGA, SDS PAGE, and CHNS analysis, Bradford assay, and ash content. All the keratin hydrolysate from different methods showed all the amide bonds present in the keratinous structure from the FTIR, while TGA followed the three-phase trend loss of the keratinous structure. Protein concentrations obtained from CH1, CH2, EH1, and EH2 were 1.40, 1.02, 1.08, and 0.45 mg/ml respectively and their protein content was 86.56, 67.63, 78.06, and 90.00%. Their molecular weights were all in different ranges while the ash content for CH1 was 20.7, CH2 was 5.27, and EH1 was 9.19. All the results obtained were compared to the pure keratin azure and EH2 showed high protein content but low protein concentration. CH1 showed the second-highest protein content but with high impurities from the extraction method shown from the ash content. [ABSTRACT FROM AUTHOR]

Keratin waste has become an increasingly serious environmental and health hazard. Keratin waste is mainly composed of keratin protein, which is one of the most difficult polymers to break down in nature and is resistant to many physical, chemical, and biological agents. With physical and chemical methods being environment damaging and costly, microbial degradation of keratin using keratinase enzyme is of great significance as it is both environment friendly and cost-effective. The aim of this study was to extract and purify keratinase from bacterial species isolated from the soil. Among the organisms, an isolate of Bacillus velezensis, coded as MAMA could break down chicken feathers within 72 hours (h). The isolated strain produced significant levels of keratinase in mineral salt medium by supplying chicken feathers as the sole source of nitrogen and carbon. Feather deterioration was observed with the naked eye, and enzyme activity was evaluated using a spectrophotometric assay. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and zymography results revealed that the keratinase protein produced by Bacillus velezensis had a molecular weight between 40 and 55 kilodalton (kDa).

The present study aimed at converting meat industry waste, particularly waste bones and chicken feathers, into biochar to recycle valuable nutrients present in it, which ultimately become part of the municipal waste. The bone biochar (BB) and feathers biochar (FB) were prepared at 550 °C, and their potential was evaluated as an organic amendment for the growth of sunflower. The ash content (AC) and fixed carbon (FC) improved significantly in prepared biochars as compared to raw feedstock. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) analyses signaled the occurrence of various functional groups viz. amide group and hydroxyapatite, porosity, and multiple nutrients. Application of BB and FB in potted soil alone as well as in composites (1:1, 1:2, 2:1) at 1%, 3%, and 5% (w/w) and synthetic fertilizer significantly increased soil pH, electrical conductivity (ECe), organic matter (OM) and water holding capacity (WHC), while reducing the bulk density (BD). The growth of plants grown in soil treated with a 2:1 composite of feathers and bone biochar at 5% application rate showed significantly greater differences in plant height, total chlorophyll content, and plant dry weight than the control but was comparable to growth with chemical fertilizer, rendering it a potential alternative to chemical-based synthetic fertilizer.

Abstract Chicken feathers that make up 4-6% of total weight of chicken are most influential waste by-product from poultry farm and slaughter. Annual worldwide generation of several tons of feather biomass raise solid waste management concerns. In environmental perspective, the burning or dumping in landfills are not promising approaches. Keratin, tough and fibrous protein, is an important polymer abundant in chicken feathers. The present study aimed at extraction, characterization of keratin from chicken feather waste. Moreover, this study was performed to evaluate the adsorption potential of keratin adsorbent for the treatment of heavy metal contaminated synthetic water. Feathers after collection was treated with sodium sulfide for the extraction of valuable keratin protein. The extracted keratin was dialyzed using cellulose membrane and freeze dried. Adsorption of metals (Zn and Cu) onto extracted keratin has been studied using batch-adsorption studies. The concentration of obtained protein from chicken feather was computed to be 0.95mg/mL. Functional groups of amide I, amide II, tryptophan, stretching C-O and bond of C-N were confirmed through FTIR. XRD analysis confirmed sem-crystalline structure of keratin whereas SEM analysis showed roughness on surface of keratin due to alkaline hydrolysis. Freundlich isotherm identified ideal parameters for removal of zinc and copper from water as eight hours of contact time, temperature of 250C. With regard to pH, the optimum level was 5.0 and 4.5 for zinc and copper respectively. After treatment with extracted keratin, the removal of 52% zinc and 69% copper from the synthetic water was observed. Results clearly indicate the potential of keratin from chicken feather for effective, economic and eco-friendly treatment of contaminated water.

Overproduction of chicken feathers is responsible for serious environmental problems worldwide. The composition of feathers is keratin protein, which is resistant and difficult to monomerize. Utilization of feather waste for biogas and organic fertilizer production can help combat environmental threat and address energy and food shortage crisis. In this study, chicken feathers were hydrolyzed using the native isolated keratinolytic bacterial strain Pseudomonas aeruginosa-C1M. Reactor digestate, a by-product of the production of biogas from hydrolyzate and grocery waste, has been shown to be used as organic fertilizer. A greenhouse study was conducted to investigate the comparative effectiveness of reactor digestate and feather hydrolyzate on the growth of spinach plants. A remarkable increase in agronomic parameters was observed when applying keratin hydrolyzate based fertilizers. Plants treated with dry hydrolyzate showed a 50% increase in leaf width. The plant height, the number of leaves per plant, the root length, the chlorophyll content, the protein content, the biomass and the nutrient content of the spinach plant were also significantly improved by using fertilizers based on keratin hydrolyzate. However, the results using the Pseudomonas aeruginosa-C1M-derived hydrolyzate were more promising and therefore suggest its application as a potential biostimulant in the agricultural industry. [ABSTRACT FROM AUTHOR]

Biosorbent chicken feathers can effectively sorb oil from seawater, making them a promising alternative to synthetic sorbents, so it is imperative that plentiful, problematic, and disruptive waste feathers are decontaminated. This study aims to evaluate and optimize the chemical treatment of waste chicken feathers (white chicken feathers (WCF) and baladi chicken feathers (BCF)) and explore their potential as a renewable biomaterial for the pollution of seawater from oil spills. Scanning electron microscopy, infrared spectroscopy, and X-ray diffraction are used for feather characterization; hydrogen peroxide (H2O2) and sodium dodecyl sulfate (SDS) are used for chemical modification due to lipids or grease covering the feather's surface having a negative effect on the oil sorption process. Chemical agents are used to remove them. At maximum lipid removal efficiency, the optimum type and concentration of chemical modifications for lipid removal from feathers are Sodium Dodecyl sulfate (SDS), with a concentration of 1.5 g/l, which has the highest lipid removal percentage at 58%, while hydrogen peroxide (H2O2) is 47%. SEM-EDX analysis indicates that BCF was more efficient than WCF. In addition, FTIR spectra confirm that lipids and proteins are presented and observed to have absorption properties. XRD diffraction shows the crystallinity index of a BCF was 30% and that of a WCF was 50%, and a BCF has a higher amorphous content. 1 g of WCF has an oil sorption efficiency of 93.3% at 10 min. contact time and 88.3% during an experiment beginning, while 1 g of BCF has a sorption efficiency of 97% at 10 min. contact time and 93% during an experiment beginning. At 50 ml of oil feed used, the maximum sorption efficiency was 67.7% (33.9 ml) and 75.4% (37.7 ml) of WCF and BCF, respectively. The oil sorption capacity values increased with the oil quantity used but decreased the sorption efficiency. Finally, these two feather types, WCF and BCF, achieved promising initial results compared to other sorbents, and their application in the petroleum industry will achieve a huge breakthrough in the field of the environment to reduce water pollution and save huge amounts of money due to the cheapness of feather material. [ABSTRACT FROM AUTHOR]

The global requirement for food enhances the synthetic fertilizers utilization, mostly for the nitrogen (N) supply in the soil, the most limiting nutrient for plant growth. The key principle of fertilizer is to intensify the plant's growth and productivity. The soil gets polluted because of the burst discharge of chemical fertilizer and as a result, the soil loses its fertility. Also, water gets polluted because of leaching along with undesirable/harmful consequences on the plant such as a decrease in productivity, root burn, etc. So, it has become important to look for a substitute for synthetic fertilizers. On the other hand, chicken feathers waste in large amounts has been produced by the poultry industry, that requires proper management. Also, the weak recyclability of chicken feathers leads to environmental pollution as a major part of the poultry waste is disposed off in landfills or burnt. Chicken feathers contain approximately 92% keratin is a good source of amino acids, peptides, and minerals. Although it is challenging to utilize them directly as a fertilizer as their recalcitrance results in slow degradation and mineralization of N in the soil. Nevertheless, hydrolysates attained from microbial or enzymatic processing of feathers provide a rich source of peptides, soluble proteins, and amino acids that support microbial growth in the rhizosphere, which encourages the uptake and use of nutrients from the soil. The water holding capacity, soil mineral content, and C/N ratio are also enhanced. Therefore, feathers biomass from animals is a good source of N and might be utilized as biofertilizers in the agroindustry to decrease the extreme utilization of traditional inorganic fertilizers. The characteristics of chicken feather waste hydrolysate show its potential utilization in organic farming, improving the microbiota and ecosystem of the soil. Thus, the present review deliberated on the importance of biofertilizers from chicken feathers waste, other biowaste, and biopolymers, along with the potential of keratin and chicken feather waste hydrolysate in the agricultural industry. [ABSTRACT FROM AUTHOR]

A new green β nucleating agent has been obtained from industrial waste. This way, pimelic acid (PA) was chemically supported on treated keratin fibers to promote the β polymorph into a polypropylene matrix using several percentages of reinforcement (0.5, 1.0, and 5.0% w/w). IR spectra suggest a successful functionalization showing the presence of a new band at 1571 cm−1, indicating a bond between PA and the keratin surface. According to the scanning electron spectroscopy, the nucleating agent was homogeneously distributed on the keratin surface. Wide angle X-ray diffraction (WAXD) patterns and differential scanning calorimetry (DSC) curves demonstrate that the functionalized keratin fibers were able to promote a high percentage of β-crystal into the polypropylene matrix (79% and 60%, respectively). The thermomechanical properties were characterized by dynamic mechanical analysis (DMA). At −30°C, the new reinforcement provides an important increase of 25% in the storage modulus compared with the raw polypropylene. The new reinforcement seems to strongly influence the mobility of the amorphous phase, shifting the Tg to higher temperatures.

Chicken feather is a massive by-product. Its incorrect disposal can lead to serious environmental impacts. However, chicken feather is a promising low-cost keratin source. Keratin products have a wide application in the food and pharmaceutical industry. Mostly, chicken feathers are hydrolyzed by hydrothermal processes, and then applied into animal feed formulations. Despite the low cost, the hydrothermal hydrolysis leads to uncontrolled and low hydrolysis yield. Therefore, the aim of this work was to develop and optimize a sequential strategy of chicken feathers hydrolysis composed of ultrasound and enzymatic hydrolysis (savinase®) steps. In the first research step an experimental design was built and the optimum hydrolysis condition was obtained at 50 °C and 12.5% (enzyme/chicken feather), using three integrated rectors containing enzyme/substrate and sodium disulfite. Then, the ultrasound probe was added in the experimental apparatus in order to investigate the enzymatic hydrolysis assisted by ultrasound treatment. The enzymatic hydrolysis assisted by ultrasound treatment led to high concentrations of peptides, including a dipeptide (245.1868 m/z). Thus, the sequential hydrolysis strategy composed by two green technologies proposed in this study, enhanced the degree of hydrolysis of chicken feathers, producing bioactive peptides that can be used as ingredients in food products and other sectors.

This systematic review presents the potential of using feather waste as a β-keratin source, including the Brazilian scenario in the generation of this byproduct. The structure and properties of α- and β-keratin, the methods commonly reported to extract keratin from poultry feathers, and applications of feather keratin-based materials are also covered in this review. The literature search for poultry production data in Brazil was conducted for the last 2 years, for the period 2021–2022. A broad literature search for extraction methods and applications of feather keratin was done for the period 2001–2022. The poultry industry is one of the largest sectors of the food industry, and Brazil was the third-largest world producer of chicken meat with more than six billion chickens slaughtered in 2021. Poultry feathers constitute about 7% weight of broilers; thus, it can be estimated that about one million tons of poultry feathers were generated in Brazil in 2021, and the improper disposal of this byproduct contributes to environmental problems and disease transmission. The most common method of reusing feathers is the production of feather meal. From economic and environmental points of view, it is advantageous to develop processes to add value to this byproduct, including the extraction of keratin. Among natural biodegradable polymers, keratin-based materials have revolutionized the field of biomaterials due to their biocompatibility and biodegradability, allowing their application in biomedical, pharmaceutical, chemical, and engineering areas. [ABSTRACT FROM AUTHOR]

Faecal Sludge (FS) contains high concentrations of pathogenic microorganisms that are 10-100 times higher than those in domestic wastewater. Proper and sustainable treatment is required to inactivate these pathogens if FS is to be recycled in agriculture, so as to minimise public health and environmental risks. Composting is one of the common low-cost technologies of sanitising FS in Urban Africa; however, it is associated with longer pathogen inactivation periods that make it commercially uneconomical. This study investigated the effect of different organic wastes types and their mixing ratios with FS on the inactivation efficiency of viable Ascaris eggs (suum and lumbricoides) during composting. Dewatered FS was mixed with market waste (MW), chicken feathers (CF) and sawdust (SD) in different ratios. Compost piles of FS:MW:SD and FS:CF:SD both in volumetric ratios of 1:2:1 and 1:3:1 were set-up in duplicate (3 m3 each), composted and monitored weekly for viable Ascaris eggs presence for a period of 15 weeks. The results suggest that the organic waste types have a significant effect on the temperature evolution and pathogen inactivation efficiency while their mixing ratios do not. Piles containing CF achieved the shortest pathogen survival period of 4 weeks compared with 6-8 weeks for those with MW. The temperature-time factor was found to be the most important variable responsible for viable Ascaris eggs inactivation. However, other mechanisms such as microbial antagonism or antibiotic action induced by indigenous microorganisms and toxic by-products such as free ammonia were found to have also played an important role in Ascaris eggs inactivation. All piles attained 100% Ascaris eggs inactivation from FS, and therefore, the compost was safe for use in agriculture. The study findings suggest that composting of FS with CF can reduce Ascaris eggs inactivation periods by 42%, which may thus reduce the operational costs of FS treatment facilities.

Keratinases have a broad range of bio-technological, pharmaceutical, industrial, agricultural and eco-friendly waste management applications owing to their ability of degrading insoluble keratin waste. The present study aims to enhance keratinase production by optimizing some production parameters during sub-merged fermentation, using Bacillus sp. In this study, total 26 bacterial strains were isolated from four different localities in Lahore i.e. Tollinton market, chicken shops in Faisal town, Johar town and Walton cantt and screened for proteolytic activity on skim milk agar. After screening for keratinolytic activity using chicken feathers as a substrate, five strains were selected. These selected strains were identified as Bacillus sp. based on their micro-morphology and biochemical tests. Out of all the selected FK-22 exhibited the maximum keratinase activity (6.86 U/mL) which was further optimized for enhanced keratinase production. The highest yield of 19.04 U/mL was obtained using medium 1 at pH 8 after 7 days of incubation at 40 °C. [ABSTRACT FROM AUTHOR]

A new green β nucleating agent has been obtained from industrial waste. This way, pimelic acid (PA) was chemically supported on treated keratin fibers to promote the β polymorph into a polypropylene matrix using several percentages of reinforcement (0.5, 1.0, and 5.0% w/w). IR spectra suggest a successful functionalization showing the presence of a new band at 1571 cm−1, indicating a bond between PA and the keratin surface. According to the scanning electron spectroscopy, the nucleating agent was homogeneously distributed on the keratin surface. Wide angle X-ray diffraction (WAXD) patterns and differential scanning calorimetry (DSC) curves demonstrate that the functionalized keratin fibers were able to promote a high percentage of β-crystal into the polypropylene matrix (79% and 60%, respectively). The thermomechanical properties were characterized by dynamic mechanical analysis (DMA). At −30°C, the new reinforcement provides an important increase of 25% in the storage modulus compared with the raw polypropylene. The new reinforcement seems to strongly influence the mobility of the amorphous phase, shifting the Tg to higher temperatures. [ABSTRACT FROM AUTHOR]

Chicken feather is a massive by-product. Its incorrect disposal can lead to serious environmental impacts. However, chicken feather is a promising low-cost keratin source. Keratin products have a wide application in the food and pharmaceutical industry. Mostly, chicken feathers are hydrolyzed by hydrothermal processes, and then applied into animal feed formulations. Despite the low cost, the hydrothermal hydrolysis leads to uncontrolled and low hydrolysis yield. Therefore, the aim of this work was to develop and optimize a sequential strategy of chicken feathers hydrolysis composed of ultrasound and enzymatic hydrolysis (savinase®) steps. In the first research step an experimental design was built and the optimum hydrolysis condition was obtained at 50 °C and 12.5% (enzyme/chicken feather), using three integrated rectors containing enzyme/substrate and sodium disulfite. Then, the ultrasound probe was added in the experimental apparatus in order to investigate the enzymatic hydrolysis assisted by ultrasound treatment. The enzymatic hydrolysis assisted by ultrasound treatment led to high concentrations of peptides, including a dipeptide (245.1868 m/z). Thus, the sequential hydrolysis strategy composed by two green technologies proposed in this study, enhanced the degree of hydrolysis of chicken feathers, producing bioactive peptides that can be used as ingredients in food products and other sectors. [ABSTRACT FROM AUTHOR]

In last decades, there has been an interest in using biogenic wastes and by-products as fillers or reinforcements to produce polymer composites. Hence, new composites materials based on a blend of biogenic chicken feathers (CFs) and polypropylene (PP) are proposed in this work and compared, from the environmental point of view, with currently used materials as neat PP and PP reinforced with glass-fibres (PP-GF). A Cradle-to-Grave Life Cycle Assessment (LCA) was performed in order to compare the environmental impact of these three materials when being used either for automotive or stationary applications. The mechanical properties of each material were taken into account to calculate the equivalent mass of each industrial application and the use phase and end of life (EoL) were included in the LCA study. The results showed that, for automotive applications and for all the materials studied (PP-GF, PP-CFs and PP) the use phase has a great contribution to the environmental impact categories considered, proving that the new developed material based on CFs (PP-CFs) would be appropriate for stationary applications but not for mobile applications as automotive ones. In addition, the EoL scenario considered, i.e. incineration with energy recovery, has proven to provide extra environmental credits. [ABSTRACT FROM AUTHOR]

A simple analytical method for the extraction and determination of three ß-lactam antibiotics in chicken tissues and feather samples was developed and validated using solid phase extraction (SPE) and liquid chromatography-ultraviolet, LC-UV, detection. The analytes were extracted with strong anion exchange (SAX) cartridges for the extract clean-up and enrichment before introduction into the LC system. The validation was carried out based on the recommendations from Commission Decision 2002/657/EC. Under optimised conditions, the proposed method offers correlation coefficients of r² ≥ 0.9991 for all the studied analytes in both matrices. Percent recovery results were found to vary between 79.7-101.8% and 94.2-101.6% for chicken feathers and tissues, respectively, with the relative standard deviation, RSD < 8.4%. The limits of detection (LOD) were in the range of 0.1-0.13 µg kg-1 and 0.1-0.15 µg kg-1 while the limits of quantification (LOQ) were in the range of 0.3-0.38 µg kg-1 and 0.3-4.5 µg kg-1 in chicken feathers and tissues, respectively. The proposed method offers good sensitivity and selectivity and all the results demonstrating that the method would be widely used for determination of ß-lactam antibiotics and other trace level antibiotics residues having similar physical and chemical properties in the matrices of varying origins. [ABSTRACT FROM AUTHOR]

The poultry processing industry is one of the most rapidly growing sectors from food industry chain, with large quantities of waste generated every year. Worldwide there were generated over 10 million tons of poultry residues eliminated in present by incineration. Chicken feathers as poultry processing industry waste represents a source of pollution for air, water and soil affecting also human health and the quality of environment. This paper presents the poultry processing industry waste to assess their potential as renewable energy source. The High Heating Value of chicken feathers is 26000 kJ/kg (dry basis) which recommends them as an energy source. Based on the experimental results, the paper proposes some waste to energy conversion solutions for energetic potential recovery of poultry processing industry waste using thermo-chemical processes. Net electric output generation for a poultry processing unit (86 t/day waste) using some energy conversion solutions can reach 4 MW for completely dried product. This solution is an alternative to incineration allowing the poultry processing industry to become its own energy producer with positive impact on expenses with incineration process. [ABSTRACT FROM AUTHOR]

Incorporation of residua into polymeric composites can be a successful approach to creating materials suitable for specific applications promoting a circular economy approach. Elastomeric (Ground Tire Rubber or GTR) and biogenic (chicken feathers or CFs) wastes were used to prepare polymeric composites in order to evaluate the tensile, acoustic and structural differences between both reinforcements. High-density polyethylene (HDPE), polypropylene (PP) and ethylene vinyl acetate (EVA) polymeric matrices were used. EVA matrix defines better compatibility with both reinforcement materials (GTR and CFs) than polyolefin matrices (HDPE and PP) as it has been corroborated by Fourier transform infrared spectroscopy (FTIR), termogravimetric analysis (TGA) and scanning electron microscopy (SEM). In addition, composites reinforced with GTR showed better acoustic properties than composites reinforced with CFs, due to the morphology of the reinforcing particles. [ABSTRACT FROM AUTHOR]

In the present study, chicken feathers (CFs), obtained from animal waste, were used as bio-adsorbent for the removal of hazardous Cr(VI) ions from aqueous solutions. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDX), x-ray diffraction (XRD), adsorption of N2 at −196 °C, thermogravimetric analysis (TGA), and point of zero charge (pHpzc) determination were used to characterize the adsorbent. The N2 adsorption results revealed high surface area and microporous structure for the adsorbent. The experimental results in batch adsorption show that optimum conditions are: pH 2.5, equilibrium contact time 180 minutes, concentration of CFs 11 g L−1, and initial Cr(VI) concentration 25 mg L−1. The experimental data on Cr(VI) adsorption were fitted using the Langmuir and Freundlich equations at different temperatures. The Langmuir adsorption model showed the best fit. The maximum monolayer capacity (qmax) of CFs was found to be 333.33 mg/g. The kinetic results of Cr(VI) ion were fitted to four kinetic models: pseudo-first-order, pseudo-second-order, intra-particle diffusion, and Elovich. The pseudo-second-order chemisorption model had a higher coefficient. The thermodynamics data showed that the adsorption process of Cr(VI) on CFs was endothermic and spontaneous. The desorption efficiency and reusability of CFs were determined for three adsorption–desorption cycles, which proved to be very effective for the removal of Cr(VI) ions from aqueous solutions. [ABSTRACT FROM AUTHOR]

This research focuses on the removal of diclofenac in aqueous phase using chicken feathers and the evaluation of the subsequent biodegradation of the obtained adsorbate/adsorbent complex using a bacterial consortium. In the first stage, the conditions that affected adsorption were evaluated, in order to optimize the loading of the feathers. Afterwards, the equilibrium was evaluated by three adsorption isotherms at 8, 15 and 25 °C; the experimental data were explained by the Langmuir model, showing that, at 8 °C the highest load was obtained (614.8 mg/g). Additionally, the process was thermodynamically explained as spontaneous and exothermic and governed by chemical and physical processes, in addition to the occurrence of a decrease in molecular disorder at the adsorbate–adsorbent interface. Likewise, the kinetic behavior was studied at 8, 15 and 25 °C, detecting that the adsorption process occurs in two stages described by the intraparticle diffusion model. Finally, an FTIR analysis was carried out, in which the groups participating in the adsorption process were shown. The second stage was the evaluation of the biodegradation process of the adsorbate/adsorbent complex. The biodegradation of diclofenac was evidenced by monitoring laccase, lignin peroxidase, manganese peroxidase and polyphenol oxidase enzymatic activities and quantifying the 50% decrease in diclofenac concentration by HPLC. Simultaneously, the degradation of the chicken feather impregnated with diclofenac was analyzed, evaluating keratinolytic activity, the presence of soluble protein, amino acids and sulfhydryl groups; the positive results of these tests confirmed the biodegradation. [ABSTRACT FROM AUTHOR]

Abstract Background Chicken feathers are the most abundant agro-wastes emanating from the poultry processing farms and present major concerns to environmentalists. Bioutilization of intractable feather wastes for the production of critical proteolytic enzymes is highly attractive from both ecological and biotechnological perspectives. Consequently, physicochemical conditions influencing keratinase production by Bacillus sp. CSK2 on chicken feathers formulation was optimized, and the keratinase was characterized. Results The highest enzyme activity of 1539.09 ± 68.14 U/mL was obtained after 48 h of incubation with optimized conditions consisting of chicken feathers (7.5 g/L), maltose (2.0 g/L), initial fermentation pH (5.0), incubation temperature (30 °C), and agitation speed (200 rpm). The keratinase showed optimal catalytic efficiency at pH 8.0 and a temperature range of 60 °C – 80 °C. The keratinase thermostability was remarkable with a half-life of above 120 min at 70 °C. Keratinase catalytic efficiency was halted by ethylenediaminetetraacetic acid and 1,10-phenanthroline. However, keratinase activity was enhanced by 2-mercaptoethanol, dimethyl sulfoxide, tween-80, but was strongly inhibited by Al3+ and Fe3+. Upon treatment with laundry detergents, the following keratinase residual activities were achieved: 85.19 ± 1.33% (Sunlight), 90.33 ± 5.95% (Surf), 80.16 ± 2.99% (Omo), 99.49 ± 3.11% (Ariel), and 87.19 ± 0.26% (Maq). Conclusion The remarkable stability of the keratinase with an admixture of organic solvents or laundry detergents portends the industrial and biotechnological significance of the biocatalyst.

The production of "environmentally friendly" composite materials involves the use of natural reinforcements and natural or hybrid resins. The first part of this paper describes how is obtained a hybrid resin from Dammar natural resin, polymerized with acrylic resin. For this hybrid resin were determined some mechanical properties, such as: Young's static modulus, breaking strength, elongation at break, water absorption, shore hardness and damping factor per unit mass together with its own frequency corresponding to the first proper mode of vibration. From the point of view of static mechanical properties, it is found that the new hybrid resin has lower properties compared to similar ones that are already studied. Notes a decrease of 2-3 units in the value of breaking strength and 600 units in the static Young's modulus. But the advantage of the proposed hybrid resin is the reduced curing time compared to similar ones. In the second part, based on the hybrid resin obtained and by reusing some waste from the agri-food industry, two new types of composite materials were molded. The first was reinforced with chicken feathers and sheets of paper and the second was reinforced with corn leaves and sheets of paper. For the two composite materials the same mechanical characteristics were determined as in the case of the hybrid resin. Finally, based on the determined properties, it is proposed to use these composites for the making of medical devices (used to immobilize fractures), of some furniture components, or some constructions formwork. [ABSTRACT FROM AUTHOR]

Keratin waste has become an increasingly serious environmental and health hazard. Keratin waste is mainly composed of keratin protein, which is one of the most difficult polymers to break down in nature and is resistant to many physical, chemical, and biological agents. With physical and chemical methods being environment damaging and costly, microbial degradation of keratin using keratinase enzyme is of great significance as it is both environment friendly and cost-effective. The aim of this study was to extract and purify keratinase from bacterial species isolated from the soil. Among the organisms, an isolate of Bacillus velezensis , coded as MAMA could break down chicken feathers within 72 hours (h). The isolated strain produced significant levels of keratinase in mineral salt medium by supplying chicken feathers as the sole source of nitrogen and carbon. Feather deterioration was observed with the naked eye, and enzyme activity was evaluated using a spectrophotometric assay. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and zymography results revealed that the keratinase protein produced by Bacillus velezensis had a molecular weight between 40 and 55 kilodalton (kDa)., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Every year the volume of production of poultry products all over the world is growing steadily. This contributes to a constant increase in the amount of by-products of poultry processing in the form of down and feather waste, which are dangerous for the environment due to the hard-to-degrade keratin protein and a large number of microbial pathogens. Therefore, the use of environmentally friendly methods for the destruction of keratin substrates due to keratinases of microorganisms is an urgent area of research. The aim of this work was to select the optimal cultivation conditions for the Bacillus megaterium strain UCM B-5710 to increase the activity of the keratinase synthesized by it. Methods. The culture was grown at 28 °C, 201 rpm for 7 days on a basic nutrient medium containing defatted chicken feathers as the only source of carbon and nitrogen. The selection of optimal cultivation conditions was carried out according to the following parameters: temperature (21 °C, 28 °C, 42 °C), stirring speed (201 rpm, 212 rpm), amount of inoculum (5 %, 10 %, 15 %, 20 %, 25 %), the initial pH value of the nutrient medium (4.0-11.0), concentration of keratin-containing substrate (0.1 %, 0.2 %, 0.5 %, 1.0 %, 1.5 %, 2.0 %), additional carbon source (glucose, galactose, lactose, maltose, sucrose, mannitol, potato and corn starch, soluble starch, soybean meal) and nitrogen (NH4Cl, NH4NO3, (NH4)2SO4, NaNO3, urea, peptone, tryptone, yeast extract and soybean meal) at a concentration of 1 %. Keratinase activity was assessed by the UV absorption at 280 nm of the hydrolysis products of keratin-containing raw materials. Protein was determined by the Lowry method. Results. The dynamics of the enzyme synthesis showed that the culture of B. megaterium UCM B-5710 exhibited the highest keratinase activity on the 3rd day, and complete splitting of feathers was observed on the 4-5th days. The selection of the concentration of the keratin-containing substrate showed that 0.5 % is the optimal concentration. The study of the influence of the initial pH value of the nutrient medium indicates that the culture grew well at pH 6.0-7.0 and pH 9.0-11.0, but at pH 8.0 its growth was very weak. The culture exhibited the maximum keratinase activity at pH 10.0. In addition, at this pH value, complete splitting of feathers was visually observed. The influence of such a key factor as temperature on the growth and synthesis of the enzyme by B. megaterium UCM B-5710 culture demonstrated complete splitting of feathers already on the 2nd day of cultivation at 42 °C, at 21 °C the culture split feathers very poorly. The introduction of the inoculum into the composition of the nutrient medium in an amount of 15 % of the volume of the medium and the mixing intensity of 212 rpm turned out to be optimal. Besides, it was shown that the introduction of an additional source of carbon or nitrogen had an ambiguous effect on the level of keratinase activity of B. megaterium UCM B-5710. Complete inhibition of enzyme synthesis was observed when ammonium sulfate was added to the nutrient medium, and partial inhibition was observed in the case of glucose, lactose, and maltose. Potato, corn, and soluble starch stimulated keratinase synthesis. The majority of inorganic nitrogen sources (ammonium chloride and nitrate) did not affect the synthesis of B. megaterium UCM B-5710 keratinase, while organic sources (urea, peptone, tryptone, yeast extract) increased the level of keratinase activity by 20-50 %. However, the most effective result was obtained using soybean meal, the addition of which to the nutrient medium increased the keratinase activity by 2.5 times. Conclusions. As a result of the studies, the optimal conditions for cultivation of the B. megaterium UCM B-5710 strain were selected: the optimum temperature for the growth and development of the culture is 42 °C, the initial pH value is 10.0, the stirring speed is 212 rpm and the amount of inoculum introduced is 15 %, an additional source of carbon and nitrogen in the form of soybean meal at a concentration of 0.5 %. This made it possible to increase the activity of keratinase by 4 times. [ABSTRACT FROM AUTHOR]

Biodegradation of keratin containing wastes viz. bird feathers, nails, hairs, animalwool is a low-cost, nutrient-rich biotechnological process that turns this plentiful waste into a low-cost, nutrient-rich substance. It is a sustainable green approach towards the solution of environmental threats created by these wastes. This study aimed to screen for potential keratinase-producing microorganisms and to optimize physicochemical parameters to produce keratinase and its characterization. Samples were collected from various poultry farms of Surat (India). Screening for keratinase-production was carried using a feather basal medium. Among these samples, 16 isolates showed keratinolytic activity in primary screening using skim milk agar medium among which, nine isolates showed keratinolytic activity using keratin agar medium. Isolate KA1a gave the highest yield of keratinase and was identified as a strain of Stenotrophomonas maltophilia (NCBI Accession number MT478451), based on 16S rRNA sequencing. It delivered highest enzyme production (108 U/ml) in the medium with feathers (2.2%), NaCl (0.5%), K2HPO4(0.3%), KH2PO4(0.4%), pH7, with 10% inoculum of young cell mass, at 37°C for 24 h under shaking conditions. Optimum temperature for keratinase activity was 40°C and pH 7.0. Enzyme showed stability over different temperature and pH for up to 90 min. It showed potential applications as a detergent additive, animal feed, and organic fertilizer. [ABSTRACT FROM AUTHOR]

Microbial keratinases’ versatility in the beneficiation of keratinous waste biomass into high-value products prompts their application in diverse spheres hence, advancing green technology and the bioeconomy. Consequently, a feather-degrading Chryseobacterium aquifrigidense FANN1 (NCBI: MW169027) was used to produce keratinase, and its biochemical properties were determined. The optimization of physicochemical parameters and analysis of the free amino acid constituents of the feather hydrolysate were also carried out. FANN1 showed a maximum keratinase yield of 1,664.55 ± 42.43 U/mL after 72 h, at optimal process conditions that included initial medium pH, incubation temperature, inoculum size, and chicken feather concentration of 8, 30°C, 4% (v/v), and 15 (g/L), respectively. Analysis of degradation product showed 50.32% and 23.25% as the protein value and total free amino acids, respectively, with a relatively high abundance of arginine (2.25%) and serine (2.03%). FANN1 keratinase was optimally active at pH 8.0 and relatively moderate to high temperature (40–50°C). EDTA and 1,10-phenanthroline inhibited the keratinase activity, and that suggests a metallo-keratinase. The enzyme showed remarkable stability in the presence of chemical agents, with residual activity 141 ± 10.38%, 98 ± 0.43%, 111 ± 1.73%, 124 ± 0.87%, 104 ± 3.89%, 107 ± 7.79%, and 112 ± 0.86% against DTT, H2O2, DMSO, acetonitrile, triton X-100, tween-80, and SDS, respectively. The residual activity of FANN1 keratinase was enhanced by Sunlight (129%), Ariel (116%), MAQ (151%), and Surf (143%) compared to the control after 60 min preincubation. Likewise, the enzyme was remarkably stable in the presence Fe3+ (120 ± 5.06%), Ca2+ (100 ± 10.33%), Na+ (122 ± 2.95%), Al3+ (106 ± 10.33%); while Co2+ (68 ± 8.22%) and Fe2+ (51 ± 8.43%) elicited the most repressive effect on keratinase activity. The findings suggest that C. aquifrigidense FANN1 is a potential candidate for keratinous wastes bio-recycling, and the associated keratinase has a good prospect for application in detergent formulation.

Featured Application: The work described in this paper has significant potential for medical applications. As an example, these peptides can be incorporated into wound dressings to treat chronic wounds, increasing their re-epithelization, or to treat other skin diseases, such as psoriasis. FAO estimates that in 2030 the poultry meat production could reach 120 million tons, which is a challenge in terms of waste management. Feathers are mainly composed of keratin, an important biomaterial. Using feathers as a source of keratin will minimize the waste generated, while contributing to supply an important material for several industries, such as pharmaceutical and biomedical. The peptides were extracted from the feathers by microbial degradation. In this study, we evaluated the peptides effect on keratinocyte metabolic activity and migration. The influence of these peptides on non-activated and activated macrophages was also assessed. It was demonstrated that depending on the keratin peptide fraction in contact with keratinocytes, it is possible to modulate the migration rate of the keratinocytes. Peptide fraction with low molecular weight increases migration, while peptides with a high range of molecular sizes decreases it. Some peptide fractions induce the secretion of TNF-α in non-activated macrophages and not on activated macrophages, demonstrating that these peptides should only be placed in contact with cells, in the context of an ongoing inflammatory process. This work is a step forward on the understanding of keratin peptides influence on keratinocytes and immune cells system cells, macrophages. [ABSTRACT FROM AUTHOR]

Streptomyces sp. 2M21 was evaluated for keratinase production in bioreactors using chicken feathers. Firstly, optimization of bioengineering parameters (agitation and aeration rates) using Response Surface Methodology was carried out in 2 L bioreactors. Optimized conditions identified by the modified quadratic model were verified as 150 rpm and 1 vvm experimentally corresponding to 351 U/ml of keratinase activity. Moreover, scaling up sequentially to 20 L bioreactors was implemented using constant impeller tip speed and constant mass transfer coefficient as key scale-up parameters. The keratinase activity in 5, 10 and 20 L bioreactors showed similar results with the one of shake flasks (412 U/ml) and 2 L bioreactors (351 U/ml)with respect to the keratinase activity values of 336, 385 and 344 U/ml, respectively. The results suggest keratinase production by evaluating chicken feathers in commercial level. Furthermore, this study has potential to contribute industrial scale production of keratinase by Streptomyces sp. 2M21 using the proposed bioreactor conditions. [ABSTRACT FROM AUTHOR]

Keratin was synthesized by alkaline hydrolysis from chicken feathers and then continue by casting method for producing bioplastics with additional various amounts of chitosan as a filler, polyvinyl alcohol (PVA) and glycerol as a plasticizer. The main purpose is analysis the effect of chitosan on the structural properties using quantitative analysis of X-ray diffraction (XRD) spectra, chemical bonding by Fourier transforms infrared (FTIR) spectra, and mechanical properties by texture analyser to the keratin-based bioplastics. Biodegradation of bioplastics was analysed from the loss of weight by burying in the soil. It's found that, the additional of chitosan (0 %, 2 %, 5 %, and 8 %) increased the crystallinity of bioplastics by 11.83 %, 11.12 %, 18.99 %, and 17.03 %, respectively, but decreasing tensile strength and elasticity of bioplastics. Degradation of bioplastic keratin-based shows that the addition of chitosan can reduce the degradation time which is directly proportional to the loss of C O bonds. The highest degradation rate is 89.29 % in 49 days for keratin-based bioplastics with 8 % chitosan, indicated that high potential for future production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-pyrolysis of chicken feathers and macadamia nutshells doubles nitrogen retention; • Co-pyrolysis does not decrease porosity development; • Demineralization increased activated carbon's porosity significantly; • Co-pyrolysis coupled with demineralization leads to functional electrode materials. Global food waste emits substantial quantities of nitrogen to the environment (6.3 Mtons annually), chicken feather (CF) waste is a major contributor to this. Pyrolysis, in particular co-pyrolysis of nitrogen-rich and lignocellulosic waste streams is a promising strategy to improve the extent of pyrolytic nitrogen retention by incorporating nitrogen in its solid biochar structure. As such, this biochar can serve as a precursor for nitrogen-enriched activated carbons for application in supercapacitors. Therefore, this study investigates the co-pyrolysis of CF with macadamia nut shells (MNS) to create nitrogen-rich activated carbons. Co-pyrolysis increased nitrogen retention during pyrolysis from 9 % to 18 % compared to CF mono-pyrolysis, while the porosity was maintained. After removing undesirable inorganic impurities by dilute acid washing, this led to a specific capacitance of 21F/g using a scan rate of 20 mV/s. Finally, cycling stability tests demonstrated good stability with 73 % capacitance retention after 10 000 cycles. [ABSTRACT FROM AUTHOR]

Poultry farming apart from being an economically viable sector, is also known to generate humongous amount of waste as chicken feathers, which needs attention. Keratin is the main structural protein of chicken feathers and is known to have great mechanical strength. As keratin contains disulphide bonds and hydrophobic residues, it is difficult to degrade chicken feathers. Acid hydrolysis and alkali hydrolysis are some of the methods, used to degrade this waste. In this regard, the present study was undertaken, to know, if house hold chemicals such as cleaning liquid (main ingredient HCL) and vinegar (acetic acid + water) can be effective in degrading the chicken feathers. Chicken feathers, were treated with both cleaning liquid and vinegar. Results showed that cleaning liquid was found to be very effective in degrading the chicken feathers rather than vinegar. Feathers, lost their structural integrity under the influence of the acid, after being exposed to 48 hrs at room temperature. but with vinegar, when feathers, even after being exposed to a period of 96 hrs, still, retained their structural integrity and no disintegration was observed. Therefore, this study suggests that acid hydrolysis using a strong acid at room temperature may be an effective way to degrade the feathers, however this method may not be a suitable one to extract keratin from the chicken feathers. In this study only a small sample of 4-5 feathers were used for acid hydrolysis, but when large scale disintegration is needed, a more ecofriendly approach may be developed and employed in future. [ABSTRACT FROM AUTHOR]

Capacitive deionization (CDI) is a promising and rapidly growing technology for water treatment and the electrode materials play a key role in improving CDI performance. In this study, high surface area activated carbon was prepared from chicken feather (CF) bio-waste through pyrolysis and KOH activation; the KOH:CF ratio (R) and activation temperature (Ta) were variable parameters. The material was characterized by using the Brunauer, Emmett and Teller (BET) method, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The lead (Pb2+) removal test was performed with a CDI cell containing the fabricated carbon electrode and 100 mg L−1 Pb(NO3)2 solution; the sample prepared with the ratio R of 1:1 and Ta = 800 °C exhibited higher Pb2+ removal efficiency of 81% and electro sorption capacity of 4.1 mg g−1 at the electrode potential 1.2 V and flow rate 5 mL min−1. Therefore, CF-derived carbon is considered as a promising CDI electrode material for removal of heavy metals from waste water.

Brazil poultry industry generates a large amount of byproducts, especially feathers. The objective of this study was to evaluate the influence of hydrolysis time and pressure on the protein content (PC) and digestibility value (DV) of the hydrolyzed feather meal (HFM) produced with: 100% chicken feathers, 100% turkey feathers and mixed (50% chicken feathers + 50% turkey feathers). There was a tendency to higher PC and DV values in the range of 30 to 40 min of hydrolysis regardless of the raw material. The use of higher pressures led to a decrease in the PC and DV, except in the HFM with 100% of turkey feathers. The adjustment of the hydrolysis time and pressure resulted in a higher protein content and digestibility values in HFM. Chicken feathers are the most suitable protein source for HFM production. However, turkey feathers can be used for processing mixed feather meal. [ABSTRACT FROM AUTHOR]

Purpose: Copper is a heavy metal that causes considerable deterioration to human health and ecosystems, so their elimination in water bodies is of great interest. Present investigation shows the efficiency of chicken feather as a natural adsorbent and its subsequent degradation in order to have an integral treatment and avoid the unconscious disposition. Methods: Optimal conditions of adsorption process were determined using the Response Surface Methodology (RSM)-Box-Behnken design (BBD) with three variables (pH, temperature and adsorbent dose). After that, the optimal conditions were used to analize the adsorption isotherms by Langmuir, Freundlich and Temkin models; also thermodynamics parameters Gibbs free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) were obtained. Finally, the biodegradation of the residue denominated "adsorbent-adsorbate" complex was evaluated through monitoring the soluble protein production, keratinolytic activity, ninhydrin positive products, sulfhydryl groups, and gravimetrically analysis. Results: The optimum conditions for the adsorption were 30°C and pH 3, the Langmuir model was better described the adsorption process at 30°C, while at 40°C was Temkin model. The chicken feather turned out a natural adsorbent competitive with respect to others used in the removal of copper in liquid systems; obtaining qmax of 7.84 and 11.48 mg/g at 30 and 40°C, respectively; it was also a favorable and spontaneous process. Finally the adsorbent used was degraded by a keratinolytic consortium. Conclusions: In this study, chicken feather was used as a low cost adsorbent for copper efficiently and with the feasibility that the adsorbent can be biodegraded and release the metal. [ABSTRACT FROM AUTHOR]

Incorporation of residua into polymeric composites can be a successful approach to creating materials suitable for specific applications promoting a circular economy approach. Elastomeric (Ground Tire Rubber or GTR) and biogenic (chicken feathers or CFs) wastes were used to prepare polymeric composites in order to evaluate the tensile, acoustic and structural differences between both reinforcements. High-density polyethylene (HDPE), polypropylene (PP) and ethylene vinyl acetate (EVA) polymeric matrices were used. EVA matrix defines better compatibility with both reinforcement materials (GTR and CFs) than polyolefin matrices (HDPE and PP) as it has been corroborated by Fourier transform infrared spectroscopy (FTIR), termogravimetric analysis (TGA) and scanning electron microscopy (SEM). In addition, composites reinforced with GTR showed better acoustic properties than composites reinforced with CFs, due to the morphology of the reinforcing particles.

South Africa is the biggest chicken meat producer in Southern Africa and generates about 258 million kg of waste feathers. Although some of this waste is beneficiated into animal feed and fertiliser there are problems in adequate digestion of the feed by animals. Consequently, there is a need to find other innovative ways of beneficiating the waste. In this paper, beneficiating of feathers by extraction of fibres for possible conversion into high value products was explored. Three mechanical methods for extracting fibres from feathers were evaluated and the properties of the resultant fibres were studied and compared: they were using a tweezer, a blender, and a novel stripping method using a pulp fluffer. The results revealed that fibres extracted from chicken feathers using a tweezer or a blender had a hollow structure whereas those from the fluffer exhibited pronounced damaging effects on the fibre structure as some barbules were detached from their rami. Fluffer fibres had the highest average length of 16.56 mm followed by blender (16.15 mm) and tweezer (14.84 mm); they were also the most flexible with an aspect ratio of 476.29. The modified pulp fluffer appeared to be a cost-effective and an efficient method of grinding feathers into commercial fibres. [ABSTRACT FROM AUTHOR]

Background: Chicken feathers are the most abundant agro-wastes emanating from the poultry processing farms and present major concerns to environmentalists. Bioutilization of intractable feather wastes for the production of critical proteolytic enzymes is highly attractive from both ecological and biotechnological perspectives. Consequently, physicochemical conditions influencing keratinase production by Bacillus sp. CSK2 on chicken feathers formulation was optimized, and the keratinase was characterized. Results: The highest enzyme activity of 1539.09 ± 68.14 U/mL was obtained after 48 h of incubation with optimized conditions consisting of chicken feathers (7.5 g/L), maltose (2.0 g/L), initial fermentation pH (5.0), incubation temperature (30 °C), and agitation speed (200 rpm). The keratinase showed optimal catalytic efficiency at pH 8.0 and a temperature range of 60 °C – 80 °C. The keratinase thermostability was remarkable with a half-life of above 120 min at 70 °C. Keratinase catalytic efficiency was halted by ethylenediaminetetraacetic acid and 1,10-phenanthroline. However, keratinase activity was enhanced by 2-mercaptoethanol, dimethyl sulfoxide, tween-80, but was strongly inhibited by Al3+ and Fe3+. Upon treatment with laundry detergents, the following keratinase residual activities were achieved: 85.19 ± 1.33% (Sunlight), 90.33 ± 5.95% (Surf), 80.16 ± 2.99% (Omo), 99.49 ± 3.11% (Ariel), and 87.19 ± 0.26% (Maq). Conclusion: The remarkable stability of the keratinase with an admixture of organic solvents or laundry detergents portends the industrial and biotechnological significance of the biocatalyst. [ABSTRACT FROM AUTHOR]

With over 1 billion tons of food waste generated annually, there is potential for the waste to be re-purposed. The generation of products from food-industry waste not only reduces the environmental burden of the materials but gives a new value to waste. A common waste material from the food industry is chicken feathers (ChF), a by-product of the chicken meat processing industry. In this work, ChF were subjected to slow pyrolysis at varying temperatures. A complete analysis was completed to determine the yield, ash, chemical composition and morphology of the samples. X-ray diffraction analysis indicated that lower temperature samples were more amorphous, whereas higher temperature samples exhibited more graphitic content. After characterization, the biocarbon was combined with poly(lactic acid) (PLA) to generate sustainable 100% biobased composites. Both composites had moduli that were more than 115% greater than that of the neat polymer. The success of the composites demonstrated that ChF biocarbon can be used as a sustainable and cost effective filler. The use of this material gives new purpose to a waste product and contributes to the goal of sustainable product development.

In the present work, the evaluation of chicken feather particles (CFP) and styrene-butadiene/chicken feather (SBS-CF) composites as modifiers for asphalt binder is presented. It is well known that elastomers are the best asphalt modifiers, because their thermoplastic behavior assists asphalts in improving the range of their mechanical properties at both low and high temperatures. Nowadays, the use of natural products and byproducts as fillers for polymer matrices has been a matter of research, and the field of asphalt modification is not the exception. Chicken feather particles (CFP) is a waste material whose main component is keratin, which offers remarkable properties. In the present work, CFP was used as a filler of a styrene-butadiene rubber matrix (SBS) with radial structure, to obtain a composite intended as an asphalt modifier. Besides, raw CFP was also tested as an asphalt modifier. Physical, thermal and rheological properties of the modified asphalts were evaluated in order to determine their degree of modification with respect to the original asphalt. The results show that the addition of raw CFP improves some physical properties as penetration and decreases the phase separation; furthermore, the asphalt modified with CFP displayed similar rheological properties to those shown by the asphalt modified with SBS, while some other properties resulted in being even better, like the phase separation, with the advantage that the CFP comes from a natural waste product. [ABSTRACT FROM AUTHOR]

Agricultural waste, particularly lignocellulose, has been used in the second generation of biogas. Coffee pulp and chicken feathers can be developed as biogas raw materials because of their suitability as a biogas substrate. This study investigates the effect of the percentage of total solids (TS), carbon to nitrogen ratio (C/N, g/g), and delignification pretreatment on biogas production from coffee pulp and chicken feathers, and aims to compose kinetics using the modified Gompertz model. The results show that adjusting the percentage of TS at low-level speeds up the degradation process, which increases chemical oxygen demand (COD) reduction and biogas production. COD reduction and biogas production increase optimally at the 25 (g/g) C/N ratio. Pretreatment delignification aids microorganisms in substrate decomposition, resulting in faster COD reduction and biogas conversion. The 25% TS and 25 (g/g) C/N ratio with the delignification process achieved the best biogas production, with biogas production of 10,438.04 mL. The Gompertz method shows that the difference in TS percentage can influence biogas production. Moreover, the method shows that biogas production is higher with the delignification process than without it.

FAO estimates that in 2030 the poultry meat production could reach 120 million tons, which is a challenge in terms of waste management. Feathers are mainly composed of keratin, an important biomaterial. Using feathers as a source of keratin will minimize the waste generated, while contributing to supply an important material for several industries, such as pharmaceutical and biomedical. The peptides were extracted from the feathers by microbial degradation. In this study, we evaluated the peptides effect on keratinocyte metabolic activity and migration. The influence of these peptides on non-activated and activated macrophages was also assessed. It was demonstrated that depending on the keratin peptide fraction in contact with keratinocytes, it is possible to modulate the migration rate of the keratinocytes. Peptide fraction with low molecular weight increases migration, while peptides with a high range of molecular sizes decreases it. Some peptide fractions induce the secretion of TNF-α in non-activated macrophages and not on activated macrophages, demonstrating that these peptides should only be placed in contact with cells, in the context of an ongoing inflammatory process. This work is a step forward on the understanding of keratin peptides influence on keratinocytes and immune cells system cells, macrophages.