Industrial Advantages and Application Prospects of Recombinant Keratin in the Hair Care Sector

Journal: Biotechnology Reports

Publication Date: December 2018

DOI: 10.1016/j.btre.2018.e00288

Original author: Abdul Basita, Faiza Asghara, Saima Sadafb, M. Waheed Akhtar

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Article Abstract: 

Hair is a key component of beauty care, yet conventional hair‑care products often deliver limited results. Commercially available keratins are typically derived from wool or poultry feathers and do not fully match the sequence of human hair keratin, which restricts their efficacy. K31 is a type I acidic keratin and the principal protein in the human hair keratin complex, playing an essential role in maintaining hair’s tensile strength. In this study, we expressed the K31 gene (46 kDa) in Escherichia coli, achieving a yield of approximately 35% of total cellular protein. Following refolding and purification by anion‑exchange FPLC, CD spectroscopy confirmed proper folding, and MALDI‑TOF mass spectrometry verified that the product exhibited the expected characteristics of human K31. When applied to chemically damaged hair, recombinant K31 increased hair diameter by up to 49%, nearly doubled the mechanical strength of bleached strands after a single treatment, and efficiently straightened curly hair with a one‑hour application. K31 markedly improved the smoothness, diameter, and mechanical strength of damaged hair, providing robust scientific evidence for the industrial application of recombinant keratins in hair‑care formulations.

I. Why K31? A Key Target for Hair Damage Repair 

Hair fibers consist of three layers: the cuticle, the cortex, and the medulla. The cortex accounts for the vast majority of the hair’s volume and determines its mechanical strength and elasticity. Keratin K31, the most abundant type I acidic keratin in the cortex, forms heterodimers with type II basic keratins (K81–K86), which further assemble into an intermediate filament network that constitutes the structural scaffold of the hair. Notably, cysteine residues comprise 7%–20% of the total amino acids in keratins, and the intramolecular and intermolecular disulfide bonds they form underpin the molecular basis of hair’s tensile strength.

Chemical perming, dyeing, and bleaching treatments penetrate deep into the hair shaft, triggering a cascade of structural damage:

Proteomic analysis has confirmed that K31 is typically the protein component most severely affected in hair damage, thereby establishing its scientific status as a primary target for hair‑damage repair.

II. Engineering-Scale Production of Recombinant K31 

This rigorous quality characterization system provides comprehensive technical assurance for the reliability of recombinant keratin as an efficacy‑enhancing ingredient.

III. Validation of the Restorative Efficacy of Recombinant K31 

The study systematically evaluated, through in vitro assays, the reparative efficacy of recombinant K31 on chemically damaged hair.

The above data demonstrate that recombinant K31 not only “fills” the physical gaps in damaged hair but also integrates into the intermediate filament protein network, forming disulfide bonds with damaged keratins to reconstruct the hair’s protein architecture at the molecular level, thereby playing a crucial role in improving hair quality and maintaining hair health.

IV. Industrial Advantages of Recombinant Keratin 

The K31 study has validated the feasibility of using recombinant keratin to repair hair. Driven by synthetic biotechnology, recombinant keratin is derived from core functional segments of human‑derived keratin genes, which are produced through microbial fermentation, expression, and purification to yield a novel biomaterial with high activity, excellent stability, and superior purity. Compared with conventional animal‑derived hydrolyzed keratin, its advantages are evident in the following four aspects:

V. Prospects for the Application of Recombinant Keratin 

Based on the scientific evidence from the K31 study, recombinant keratin holds great potential for applications in the hair-care industry:

VI. Summary and Outlook 

Research on the reparative efficacy of K31 has, at the molecular level, validated the feasibility and effectiveness of the scientific pathway “supplementation of human‑derived keratin → reconstruction of hair structure → restoration of mechanical properties,” thereby providing a robust empirical foundation for the application of recombinant keratin in hair‑care formulations.

Recombinant keratin, as a next‑generation biomaterial, has broken through the performance ceiling of traditional animal‑derived ingredients, driving a generational shift in hair care from “surface conditioning” to “structural repair.” With ongoing technological advancements, recombinant keratin is poised to become the cornerstone ingredient of the next‑generation hair‑care market, paving the way for precision‑based repair and injecting sustained innovation into the global hair‑health industry.

Disclaimer

The copyright of the above content belongs to the original author. The views expressed herein are for informational and discussion purposes only and are not intended for commercial use. The opinions presented do not constitute medical treatment recommendations, nor do they amount to investment advice.