The Effect of Ultrasonication on the Quality of Keratin Extraction Based on Ionic Liquid from Duck Feather
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Keywords:
keratin extraction, duck feather, solvent extraction, ultrasonic-assisted extraction, pH variation
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Abstract
This study investigates the effect of ultrasonic-assisted extraction (UAE) and solvent extraction (SE) on keratin recovery from duck feathers using sodium sulfide-based ionic liquids under different pH conditions. The results showed that SE at acidic pH (pH=3) achieved the highest yield (92%), whereas UAE showed lower recovery (28%) under mildly acidic conditions (pH=5). Spectroscopic and electrophoretic analyses using FTIR confirmed the β-sheet structure with characteristic peaks at 3400 cm−1 (O–H and N–H stretching) and 1660 cm−1 (C=O stretching). Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis analysis (SDS-PAGE) revealed protein bands in the 15–25 kDa range, typical of β-keratin, with higher intensity in SE. Morphological analysis using SEM revealed finer and more homogeneous particles for UAE, while SE produced denser aggregates. Thermal analysis revealed two main degradation stages, occurring at 0–100 °C and 250–500 °C, with UAE samples exhibiting lower residual mass (5.46%) than SE (8.65%). Particle size analysis showed UAE samples had larger but more uniformly distributed particles. XRD results confirmed semi-crystalline structures, with UAE increasing amorphous content and SE maintaining crystallinity. These findings highlight the complementary advantages for tailoring keratin properties toward diverse applications.
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Perdana, S. S. P., Kusumawati, N., Basukiwardojo, M. M. S., Setiarso, P., Djalilah, G. N., & Rahmawati, K. (2025). The Effect of Ultrasonication on the Quality of Keratin Extraction Based on Ionic Liquid from Duck Feather. Communications in Science and Technology, 10(2), 267–275. https://doi.org/10.21924/cst.10.2.2025.1785
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References
1. N. Raydan, “Development of new adhesives based on keratin extracted from duck feathers for the production of composite materials,” 2024, [Online]. Available: https://theses.hal.science/tel-04801787v1
2. E. Commission, D.-G. for Agriculture, and R. Development, EU agricultural outlook for markets, income and environment 2022-2032. Publications Office of the European Union, 2022. doi: doi/10.2762/29222.
3. Park, G., Lee, K., Lee, Y., Kim, Y., Jeon C., Lee, O., Kim, Y., Son, H. “Biodegradation and valorization of feather waste using the keratinase-producing bacteria and their application in environmentally hazardous industrial processes,” J. Environ. Manage., vol. 346, p. 118986, 2023, doi: https://doi.org/10.1016/j.jenvman.2023.118986.
4. Ismoyowati., Suswoyo, I., Rosidi., Mugiyono, S., and Hidayat, N., “The Effect of Environmental Factor, Population and Age of Duck on Egg Production,” Anim. Prod., vol. 22, no. 2, pp. 118–125, 2020, doi: 10.20884/1.jap.2020.22.2.51.
5. Alvarez, S., Raydan, N., Svahn, I., Gontier, E., Rischka, K., Charrier, B., Robles, E., “Assessment and Characterization of Duck Feathers as Potential Source of Biopolymers from an Upcycling Perspective,” Sustain., vol. 15, no. 19, 2023, doi: 10.3390/su151914201.
6. Chen, H., Gao, S., Li, Y., Xu, Hui-Juan., Li, W., Wang, J., and Zhang, Y., “Valorization of Livestock Keratin Waste: Application in Agricultural Fields,” Int. J. Environ. Res. Public Health, vol. 19, no. 11, 2022, doi: 10.3390/ijerph19116681.
7. Dubey, D. K., Agarwal, S., Yadav, M.P., Goswami, A., Ravat, A., “THE STUDY OF THE EFFECTS OF IMPROPER HAZARDOUS WASTE DISPOSAL ON ECOSYSTEMS,” Indian J. Sci. Res., vol. 4, no. 4, pp. 130–136, 2024.
8. Ouakarrouch, M., El Azhary K., Laaroussi, N., Garoum, M., and Kifani-Sahban, F., “Thermal performances and environmental analysis of a new composite building material based on gypsum plaster and chicken feathers waste,” Therm. Sci. Eng. Prog., vol. 19, p. 100642, 2020, doi: https://doi.org/10.1016/j.tsep.2020.100642.
9. Chilakamarry, C. R., Mahmood, S., Saffe, S. N. B. M., Arifin, M. A. B., Gupta, A., Sikkandar, M. Y., Begum, S., Narasaiah, B., “Extraction and application of keratin from natural resources: a review,” 3 Biotech, vol. 11, no. 5, pp. 1–12, 2021, doi: 10.1007/s13205-021-02734-7.
10. Tran, C. D., and Mututuvari, T. M., “Cellulose, Chitosan and Keratin Composite Materials: Facile and Recyclable Synthesis, Conformation and Properties,” ACS Sustain. Chem. Eng., vol. 4, no. 3, pp. 1850–1861, Mar. 2016, doi: 10.1021/acssuschemeng.6b00084.
11. Wu, Y., Gao, H., Liu, X., Qin, C., Wang, B., Xu, J., Zhai, C., & Nie, Y., “Efficient and regulable extraction of keratin from yak hair using imidazolium-based ionic liquids,” J. Mol. Liq., vol. 388, p. 122725, 2023, doi: https://doi.org/10.1016/j.molliq.2023.122725.
12. Wang, J., Zhao, Z., Yuan, H., Gao, H., and Nie, Y., “Effective Extraction of Keratin from Human Hair under Mild Conditions Using DES Based on Choline Chloride and Ethanolamine,” ACS Sustain. Chem. Eng., vol. 12, no. 1, pp. 534–542, Jan. 2024, doi: 10.1021/acssuschemeng.3c06622.
13. Nuutinen, E. M., Virtanen, T., Lantto, R., Vähä-Nissi, M., and Jääskeläinen, A. S., “Ductile keratin films from deep eutectic solvent-fractionated feathers,” RSC Adv., vol. 11, no. 44, pp. 27512–27522, 2021, doi: 10.1039/d1ra05123g.
14. Eslahi, N., Dadashian, F., and Nejad, N. H., “An investigation on keratin extraction from wool and feather waste by enzymatic hydrolysis.,” Prep. Biochem. Biotechnol., vol. 43, no. 7, pp. 624–648, 2013, doi: 10.1080/10826068.2013.763826.
15. Moktip, T., Salaipeth, L., Cope, A. E., Taherzadeh, M. J., Watanabe, T., and Phitsuwan, P., “Current Understanding of Feather Keratin and Keratinase and Their Applications in Biotechnology,” Biochem. Res. Int., vol. 2025, no. 1, 2025, doi: 10.1155/bri/6619273.
16. Qin, X., Yang, C., Guo, Y., Liu, J., Bitter, J. H., Scott, E. L., and Zhang, C., “Effect of ultrasound on keratin valorization from chicken feather waste: Process optimization and keratin characterization,” Ultrason. Sonochem., vol. 93, no. November 2022, p. 106297, 2023, doi: 10.1016/j.ultsonch.2023.106297.
17. Basukiwardojo, M. M. S., Kusumawati, N., Asri, M. T., Dzulkarnain, S. A., Al hafidl, A. N., Kahfi, A., Nabila, M. A., Setiawan, F., Isyrak, L., and Rahmawati, K., “Ionic liquid ultrasound-assisted extraction (IL-UAE) for duck feather keratin and in silico evaluation as a potential procollagen n-endopeptidase inhibitor,” Commun. Sci. Technol., vol. 10, no. 1, pp. 75–86, 2025, doi: 10.21924/cst.10.1.2025.1669.
18. Feroz, S., Muhammad, N., Dias, G., and Alsaiari, M. A., “Extraction of keratin from sheep wool fibres using aqueous ionic liquids assisted probe sonication technology,” J. Mol. Liq., vol. 350, p. 118595, 2022, doi: https://doi.org/10.1016/j.molliq.2022.118595.
19. Serna-Vázquez, J., Ahmad, M. Z., Boczkaj, G., and Castro-Muñoz, R., “Latest insights on novel deep eutectic solvents (DES) for sustainable extraction of phenolic compounds from natural sources,” Molecules, vol. 26, no. 16, 2021, doi: 10.3390/molecules26165037.
20. Jahan, K., Ashfaq, A., Younis, K., Yousuf, O., and Islam, R. U., “A review of the effects of ultrasound-assisted extraction factors on plant protein yield and functional properties,” J. Food Meas. Charact., vol. 16, no. 4, pp. 2875–2883, 2022, doi: 10.1007/s11694-022-01390-6.
21. Córdova, A., Catal´an, S., Carrasco, V., Farias, F. O., Trentin, J., L´opez, J., Salazar, F., and Mussagy, C. U., “Sustainable assessment of ultrasound-assisted extraction of anthocyanins with bio-based solvents for upgrading grape pomace Cabernet Sauvignon derived from a winemaking process,” Ultrason. Sonochem., vol. 112, no. October 2024, 2025, doi: 10.1016/j.ultsonch.2024.107201.
22. Bouizgma, K., Rabbah, N., Abbas, Z., and Abourriche, A., “Unlocking sustainable extraction of natural antioxidants: Green solvents, smart technologies, scalability and future directions,” Sep. Sci. Technol., vol. 60, no. 6, pp. 657–683, 2025, doi: 10.1080/01496395.2025.2452411.
23. Zhang, W., Boateng, I. D., and Xu, J., “How does ultrasound-assisted ionic liquid treatment affect protein? A comprehensive review of their potential mechanisms, safety evaluation, and physicochemical and functional properties,” Compr. Rev. Food Sci. Food Saf., vol. 23, no. 1, p. e13261, 2024, doi: https://doi.org/10.1111/1541-4337.13261.
24. Lawrance, A., Mary, D. L. R., Felicita, A. E. S., and Arockianathan, P. M., “Physico-chemical Characteristics of Keratin Extracted from Three Commercial Bird Feathers and their Antibacterial Activity,” Asian J. Chem., vol. 36, no. 8, pp. 1803–1811, 2024, doi: 10.14233/ajchem.2024.31728.
25. Lyu, l., Su, S., Lu, J., Zhou, X., and Gao, Y., “Structural characteristics and sound absorption properties of different kinds of waste feather fibers,” Text. Res. J., vol. 93, no. 9–10, pp. 2138–2148, 2023, doi: 10.1177/00405175221130521.
26. Sun, J., Santiago, G. M., Yan, F., Zhou, W., Rudolf, P., Portale, G., and Kamperman, M., “Bioinspired Processing of Keratin into Upcycled Fibers through pH-Induced Coacervation,” ACS Sustain. Chem. Eng., vol. 11, no. 5, pp. 1985–1994, 2023, doi: 10.1021/acssuschemeng.2c06865.
27. Pourjavaheri, F., Pour, S. O., Jones, O. A. H., Smooker, P. M., Brklja?a, R., Sherkat, F., Blanch, E. W., Gupta, A., Shanks, R. A., “Extraction of keratin from waste chicken feathers using sodium sulfide and L-cysteine,” Process Biochem., vol. 82, no. December 2018, pp. 205–214, 2019, doi: 10.1016/j.procbio.2019.04.010.
28. Meko, O. A., Eraga, S. O., and Arhewoh, M. I., “Effect of Extraction Parameters on Some Properties of Keratin obtained From Waste Chicken Feathers,” Trop. J. Nat. Prod. Res., vol. 8, no. 6, pp. 7423–7430, 2024, doi: 10.26538/tjnpr/v8i6.13.
29. Rosarina, D., Narawangsa, D. R., Chandra, N. S. R., Sari, E., and Hermansyah, H., “Optimization of Ultrasonic—Assisted Extraction (UAE) Method Using Natural Deep Eutectic Solvent (NADES) to Increase Curcuminoid Yield from Curcuma longa L., Curcuma xanthorrhiza, and Curcuma mangga Val.,” Molecules, vol. 27, no. 18, 2022, doi: 10.3390/molecules27186080.
30. Škerget, M., Colnik, M., Zemlji?c, L. F., Gradišnik, L., Semren, T. Z., Lovakovi´c, B. T., and Maver, U., “Efficient and Green Isolation of Keratin from Poultry Feathers by Subcritical Water,” Polymers (Basel)., vol. 15, no. 12, pp. 1–15, 2023, doi: 10.3390/polym15122658.
31. Tinoco, A., Gonçalves, F., Costa, A. F., Freitas, D. S., Cavaco-Paulo, A., and Ribeiro, A., “Keratin:Zein particles as vehicles for fragrance release on hair,” Ind. Crops Prod., vol. 159, p. 113067, 2021, doi: https://doi.org/10.1016/j.indcrop.2020.113067.
32. Duman, ?., and Küçük, M., “Production and characterization of keratin microparticles obtained from wool fibers by cryogenic milling method,” Part. Sci. Technol., vol. 40, no. 8, pp. 933–941, 2022, doi: 10.1080/02726351.2022.2028321.
33. Mattiello, S., Guzzini, A., Giudice, A. D., Santulli, C., Antonini, M., Lupidi, G., and Gunnella, R., “Physico-Chemical Characterization of Keratin from Wool and Chicken Feathers Extracted Using Refined Chemical Methods,” Polymers (Basel)., vol. 15, no. 1, pp. 1–15, 2023, doi: 10.3390/polym15010181.
34. Xu, X., Wang, Z., Li, M., Su, Y., Zhang, Q., Zhang, S., Hu, J., “Reconstructed Hierarchically Structured Keratin Fibers with Shape-Memory Features Based on Reversible Secondary-Structure Transformation.,” Adv. Mater., vol. 35, no. 41, p. e2304725, Oct. 2023, doi: 10.1002/adma.202304725.
35. Jain, A., Behera, M., Mahapatra, C., Sundaresan, N. R., and Chatterjee, K., “Nanostructured polymer scaffold decorated with cerium oxide nanoparticles toward engineering an antioxidant and anti-hypertrophic cardiac patch,” Mater. Sci. Eng. C, vol. 118, no. August 2020, 2021, doi: 10.1016/j.msec.2020.111416.
36. Banasaz, S., and Ferraro, V., “Keratin from Animal By-Products: Structure, Characterization, Extraction and Application—A Review,” Polymers (Basel)., vol. 16, no. 14, 2024, doi: 10.3390/polym16141999.
37. Senthilkumar, N., Chowdhury, S., and Sanpui, P., “Extraction of keratin from keratinous wastes: current status and future directions,” J. Mater. Cycles Waste Manag., vol. 25, no. 1, pp. 1–16, 2023, doi: 10.1007/s10163-022-01492-9.
38. Shubha, A., Sharmita, G., and Manaswi, R., “Recent advances in preparation and biomedical applications of keratin based biomaterials,” Biotechnol. Sustain. Mater., vol. 1, no. 1, pp. 1–27, 2024, doi: 10.1186/s44316-024-00016-9.
39. Giannelli, M., Guerrini, A., Ballestri, M., Aluigi, A., Zamboni, R., Sotgiu, G., and Posati, T., “Bioactive Keratin and Fibroin Nanoparticles: An Overview of Their Preparation Strategies,” Nanomaterials, vol. 12, no. 9, 2022, doi: 10.3390/nano12091406.
40. Wang, Y., Liu, J., Zhang, Z., Meng, X., Yang, T., Shi, W., He, R., and Ma, H., “Insights into Ultrasonication Treatment on the Characteristics of Cereal Proteins: Functionality, Conformational and Physicochemical Characteristics,” Foods, vol. 12, no. 5, 2023, doi: 10.3390/foods12050971.
41. Amin, S., Abbas, M., Ashgar, Z., Ghani, N., Shaheen, S., Hassan, F., Akram, R., and Yousaf, H. S., “Extraction of Keratin from Chicken Feathers and its Application in the Treatment of Contaminated Water: an Eco-Friendly Approach,” Brazilian Arch. Biol. Technol., vol. 67, 2024, doi: 10.1590/1678-4324-2024220892.
2. E. Commission, D.-G. for Agriculture, and R. Development, EU agricultural outlook for markets, income and environment 2022-2032. Publications Office of the European Union, 2022. doi: doi/10.2762/29222.
3. Park, G., Lee, K., Lee, Y., Kim, Y., Jeon C., Lee, O., Kim, Y., Son, H. “Biodegradation and valorization of feather waste using the keratinase-producing bacteria and their application in environmentally hazardous industrial processes,” J. Environ. Manage., vol. 346, p. 118986, 2023, doi: https://doi.org/10.1016/j.jenvman.2023.118986.
4. Ismoyowati., Suswoyo, I., Rosidi., Mugiyono, S., and Hidayat, N., “The Effect of Environmental Factor, Population and Age of Duck on Egg Production,” Anim. Prod., vol. 22, no. 2, pp. 118–125, 2020, doi: 10.20884/1.jap.2020.22.2.51.
5. Alvarez, S., Raydan, N., Svahn, I., Gontier, E., Rischka, K., Charrier, B., Robles, E., “Assessment and Characterization of Duck Feathers as Potential Source of Biopolymers from an Upcycling Perspective,” Sustain., vol. 15, no. 19, 2023, doi: 10.3390/su151914201.
6. Chen, H., Gao, S., Li, Y., Xu, Hui-Juan., Li, W., Wang, J., and Zhang, Y., “Valorization of Livestock Keratin Waste: Application in Agricultural Fields,” Int. J. Environ. Res. Public Health, vol. 19, no. 11, 2022, doi: 10.3390/ijerph19116681.
7. Dubey, D. K., Agarwal, S., Yadav, M.P., Goswami, A., Ravat, A., “THE STUDY OF THE EFFECTS OF IMPROPER HAZARDOUS WASTE DISPOSAL ON ECOSYSTEMS,” Indian J. Sci. Res., vol. 4, no. 4, pp. 130–136, 2024.
8. Ouakarrouch, M., El Azhary K., Laaroussi, N., Garoum, M., and Kifani-Sahban, F., “Thermal performances and environmental analysis of a new composite building material based on gypsum plaster and chicken feathers waste,” Therm. Sci. Eng. Prog., vol. 19, p. 100642, 2020, doi: https://doi.org/10.1016/j.tsep.2020.100642.
9. Chilakamarry, C. R., Mahmood, S., Saffe, S. N. B. M., Arifin, M. A. B., Gupta, A., Sikkandar, M. Y., Begum, S., Narasaiah, B., “Extraction and application of keratin from natural resources: a review,” 3 Biotech, vol. 11, no. 5, pp. 1–12, 2021, doi: 10.1007/s13205-021-02734-7.
10. Tran, C. D., and Mututuvari, T. M., “Cellulose, Chitosan and Keratin Composite Materials: Facile and Recyclable Synthesis, Conformation and Properties,” ACS Sustain. Chem. Eng., vol. 4, no. 3, pp. 1850–1861, Mar. 2016, doi: 10.1021/acssuschemeng.6b00084.
11. Wu, Y., Gao, H., Liu, X., Qin, C., Wang, B., Xu, J., Zhai, C., & Nie, Y., “Efficient and regulable extraction of keratin from yak hair using imidazolium-based ionic liquids,” J. Mol. Liq., vol. 388, p. 122725, 2023, doi: https://doi.org/10.1016/j.molliq.2023.122725.
12. Wang, J., Zhao, Z., Yuan, H., Gao, H., and Nie, Y., “Effective Extraction of Keratin from Human Hair under Mild Conditions Using DES Based on Choline Chloride and Ethanolamine,” ACS Sustain. Chem. Eng., vol. 12, no. 1, pp. 534–542, Jan. 2024, doi: 10.1021/acssuschemeng.3c06622.
13. Nuutinen, E. M., Virtanen, T., Lantto, R., Vähä-Nissi, M., and Jääskeläinen, A. S., “Ductile keratin films from deep eutectic solvent-fractionated feathers,” RSC Adv., vol. 11, no. 44, pp. 27512–27522, 2021, doi: 10.1039/d1ra05123g.
14. Eslahi, N., Dadashian, F., and Nejad, N. H., “An investigation on keratin extraction from wool and feather waste by enzymatic hydrolysis.,” Prep. Biochem. Biotechnol., vol. 43, no. 7, pp. 624–648, 2013, doi: 10.1080/10826068.2013.763826.
15. Moktip, T., Salaipeth, L., Cope, A. E., Taherzadeh, M. J., Watanabe, T., and Phitsuwan, P., “Current Understanding of Feather Keratin and Keratinase and Their Applications in Biotechnology,” Biochem. Res. Int., vol. 2025, no. 1, 2025, doi: 10.1155/bri/6619273.
16. Qin, X., Yang, C., Guo, Y., Liu, J., Bitter, J. H., Scott, E. L., and Zhang, C., “Effect of ultrasound on keratin valorization from chicken feather waste: Process optimization and keratin characterization,” Ultrason. Sonochem., vol. 93, no. November 2022, p. 106297, 2023, doi: 10.1016/j.ultsonch.2023.106297.
17. Basukiwardojo, M. M. S., Kusumawati, N., Asri, M. T., Dzulkarnain, S. A., Al hafidl, A. N., Kahfi, A., Nabila, M. A., Setiawan, F., Isyrak, L., and Rahmawati, K., “Ionic liquid ultrasound-assisted extraction (IL-UAE) for duck feather keratin and in silico evaluation as a potential procollagen n-endopeptidase inhibitor,” Commun. Sci. Technol., vol. 10, no. 1, pp. 75–86, 2025, doi: 10.21924/cst.10.1.2025.1669.
18. Feroz, S., Muhammad, N., Dias, G., and Alsaiari, M. A., “Extraction of keratin from sheep wool fibres using aqueous ionic liquids assisted probe sonication technology,” J. Mol. Liq., vol. 350, p. 118595, 2022, doi: https://doi.org/10.1016/j.molliq.2022.118595.
19. Serna-Vázquez, J., Ahmad, M. Z., Boczkaj, G., and Castro-Muñoz, R., “Latest insights on novel deep eutectic solvents (DES) for sustainable extraction of phenolic compounds from natural sources,” Molecules, vol. 26, no. 16, 2021, doi: 10.3390/molecules26165037.
20. Jahan, K., Ashfaq, A., Younis, K., Yousuf, O., and Islam, R. U., “A review of the effects of ultrasound-assisted extraction factors on plant protein yield and functional properties,” J. Food Meas. Charact., vol. 16, no. 4, pp. 2875–2883, 2022, doi: 10.1007/s11694-022-01390-6.
21. Córdova, A., Catal´an, S., Carrasco, V., Farias, F. O., Trentin, J., L´opez, J., Salazar, F., and Mussagy, C. U., “Sustainable assessment of ultrasound-assisted extraction of anthocyanins with bio-based solvents for upgrading grape pomace Cabernet Sauvignon derived from a winemaking process,” Ultrason. Sonochem., vol. 112, no. October 2024, 2025, doi: 10.1016/j.ultsonch.2024.107201.
22. Bouizgma, K., Rabbah, N., Abbas, Z., and Abourriche, A., “Unlocking sustainable extraction of natural antioxidants: Green solvents, smart technologies, scalability and future directions,” Sep. Sci. Technol., vol. 60, no. 6, pp. 657–683, 2025, doi: 10.1080/01496395.2025.2452411.
23. Zhang, W., Boateng, I. D., and Xu, J., “How does ultrasound-assisted ionic liquid treatment affect protein? A comprehensive review of their potential mechanisms, safety evaluation, and physicochemical and functional properties,” Compr. Rev. Food Sci. Food Saf., vol. 23, no. 1, p. e13261, 2024, doi: https://doi.org/10.1111/1541-4337.13261.
24. Lawrance, A., Mary, D. L. R., Felicita, A. E. S., and Arockianathan, P. M., “Physico-chemical Characteristics of Keratin Extracted from Three Commercial Bird Feathers and their Antibacterial Activity,” Asian J. Chem., vol. 36, no. 8, pp. 1803–1811, 2024, doi: 10.14233/ajchem.2024.31728.
25. Lyu, l., Su, S., Lu, J., Zhou, X., and Gao, Y., “Structural characteristics and sound absorption properties of different kinds of waste feather fibers,” Text. Res. J., vol. 93, no. 9–10, pp. 2138–2148, 2023, doi: 10.1177/00405175221130521.
26. Sun, J., Santiago, G. M., Yan, F., Zhou, W., Rudolf, P., Portale, G., and Kamperman, M., “Bioinspired Processing of Keratin into Upcycled Fibers through pH-Induced Coacervation,” ACS Sustain. Chem. Eng., vol. 11, no. 5, pp. 1985–1994, 2023, doi: 10.1021/acssuschemeng.2c06865.
27. Pourjavaheri, F., Pour, S. O., Jones, O. A. H., Smooker, P. M., Brklja?a, R., Sherkat, F., Blanch, E. W., Gupta, A., Shanks, R. A., “Extraction of keratin from waste chicken feathers using sodium sulfide and L-cysteine,” Process Biochem., vol. 82, no. December 2018, pp. 205–214, 2019, doi: 10.1016/j.procbio.2019.04.010.
28. Meko, O. A., Eraga, S. O., and Arhewoh, M. I., “Effect of Extraction Parameters on Some Properties of Keratin obtained From Waste Chicken Feathers,” Trop. J. Nat. Prod. Res., vol. 8, no. 6, pp. 7423–7430, 2024, doi: 10.26538/tjnpr/v8i6.13.
29. Rosarina, D., Narawangsa, D. R., Chandra, N. S. R., Sari, E., and Hermansyah, H., “Optimization of Ultrasonic—Assisted Extraction (UAE) Method Using Natural Deep Eutectic Solvent (NADES) to Increase Curcuminoid Yield from Curcuma longa L., Curcuma xanthorrhiza, and Curcuma mangga Val.,” Molecules, vol. 27, no. 18, 2022, doi: 10.3390/molecules27186080.
30. Škerget, M., Colnik, M., Zemlji?c, L. F., Gradišnik, L., Semren, T. Z., Lovakovi´c, B. T., and Maver, U., “Efficient and Green Isolation of Keratin from Poultry Feathers by Subcritical Water,” Polymers (Basel)., vol. 15, no. 12, pp. 1–15, 2023, doi: 10.3390/polym15122658.
31. Tinoco, A., Gonçalves, F., Costa, A. F., Freitas, D. S., Cavaco-Paulo, A., and Ribeiro, A., “Keratin:Zein particles as vehicles for fragrance release on hair,” Ind. Crops Prod., vol. 159, p. 113067, 2021, doi: https://doi.org/10.1016/j.indcrop.2020.113067.
32. Duman, ?., and Küçük, M., “Production and characterization of keratin microparticles obtained from wool fibers by cryogenic milling method,” Part. Sci. Technol., vol. 40, no. 8, pp. 933–941, 2022, doi: 10.1080/02726351.2022.2028321.
33. Mattiello, S., Guzzini, A., Giudice, A. D., Santulli, C., Antonini, M., Lupidi, G., and Gunnella, R., “Physico-Chemical Characterization of Keratin from Wool and Chicken Feathers Extracted Using Refined Chemical Methods,” Polymers (Basel)., vol. 15, no. 1, pp. 1–15, 2023, doi: 10.3390/polym15010181.
34. Xu, X., Wang, Z., Li, M., Su, Y., Zhang, Q., Zhang, S., Hu, J., “Reconstructed Hierarchically Structured Keratin Fibers with Shape-Memory Features Based on Reversible Secondary-Structure Transformation.,” Adv. Mater., vol. 35, no. 41, p. e2304725, Oct. 2023, doi: 10.1002/adma.202304725.
35. Jain, A., Behera, M., Mahapatra, C., Sundaresan, N. R., and Chatterjee, K., “Nanostructured polymer scaffold decorated with cerium oxide nanoparticles toward engineering an antioxidant and anti-hypertrophic cardiac patch,” Mater. Sci. Eng. C, vol. 118, no. August 2020, 2021, doi: 10.1016/j.msec.2020.111416.
36. Banasaz, S., and Ferraro, V., “Keratin from Animal By-Products: Structure, Characterization, Extraction and Application—A Review,” Polymers (Basel)., vol. 16, no. 14, 2024, doi: 10.3390/polym16141999.
37. Senthilkumar, N., Chowdhury, S., and Sanpui, P., “Extraction of keratin from keratinous wastes: current status and future directions,” J. Mater. Cycles Waste Manag., vol. 25, no. 1, pp. 1–16, 2023, doi: 10.1007/s10163-022-01492-9.
38. Shubha, A., Sharmita, G., and Manaswi, R., “Recent advances in preparation and biomedical applications of keratin based biomaterials,” Biotechnol. Sustain. Mater., vol. 1, no. 1, pp. 1–27, 2024, doi: 10.1186/s44316-024-00016-9.
39. Giannelli, M., Guerrini, A., Ballestri, M., Aluigi, A., Zamboni, R., Sotgiu, G., and Posati, T., “Bioactive Keratin and Fibroin Nanoparticles: An Overview of Their Preparation Strategies,” Nanomaterials, vol. 12, no. 9, 2022, doi: 10.3390/nano12091406.
40. Wang, Y., Liu, J., Zhang, Z., Meng, X., Yang, T., Shi, W., He, R., and Ma, H., “Insights into Ultrasonication Treatment on the Characteristics of Cereal Proteins: Functionality, Conformational and Physicochemical Characteristics,” Foods, vol. 12, no. 5, 2023, doi: 10.3390/foods12050971.
41. Amin, S., Abbas, M., Ashgar, Z., Ghani, N., Shaheen, S., Hassan, F., Akram, R., and Yousaf, H. S., “Extraction of Keratin from Chicken Feathers and its Application in the Treatment of Contaminated Water: an Eco-Friendly Approach,” Brazilian Arch. Biol. Technol., vol. 67, 2024, doi: 10.1590/1678-4324-2024220892.