Brown Algae as a valuable substrate for the cost-effective production of poly-γ-glutamic acid for applications in cream formulations

Poly-γ-glutamic acid (γ-PGA) is a carboxylic-acid-rich, bio-derived, water-soluble, edible, hydrating, non-immunogenic polymer produced naturally by several microorganisms. Here, we re-emphasise the ability of Bacillus subtilis natto to naturally produce γ-PGA on whole seaweed, as well as for the yields and chemical properties of the material to be affected by the presence of Mn(2+). Hyaluronic acid (HA) is an extracellular glycosaminoglycan which presents a high concentration of carboxylic acid and hydroxyl groups, being key in fulfilling numerous applications. Currently, there are strong environmental (solvent use), social (non-vegan extraction), and economic factors pushing for the biosynthesis of this material through prokaryotic microorganisms, which is not yet scalable or sustainable. Our study aimed to investigate an innovative raw material which can combine both superior hygroscopicity and UV protection to the cosmetic industry. Comparable hydration effect of commercially available γ-PGA to conventional moisturising agents (HA and glycerol) was observed; however, greater hydration capacity was observed from seaweed-derived γ-PGA. Herewith, successful incorporation of seaweed-derived γ-PGA (0.2–2 w/v%) was achieved for several model cream systems with absorbances reported at 300 and 400 nm. All γ-PGA-based creams displayed shear thinning behaviour as the viscosity decreased, following increasing shear rates. Although the use of commercial γ-PGA within creams did not suggest a significant effect in rheological behaviour, this was confirmed to be a result of the similar molecular weight. Seaweed-derived γ-PGA cream systems did not display any negative effect on model HaCaT keratinocytes by means of in vitro MTT analysis.

Citation

Parati, M., Philip, C., Allinson, S. L., Mendrek, B., Khalil, I., Tchuenbou-Magaia, F., Kowalczuk, M., Adamus, G., & Radecka, I. (2024). Brown Algae as a Valuable Substrate for the Cost-Effective Production of Poly-γ-Glutamic Acid for Applications in Cream Formulations. Polymers, 16(14), Article number 2091. https://doi.org/10.3390/polym16142091

PubMed ID

39065408 (pubmed)

Type

Journal article

Language

en

Description

© 2024 The Authors. Published by MDPI. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.3390/polym16142091

ISSN

2073-4360

EISSN

2073-4360

Rights

Licence for published version: Creative Commons Attribution 4.0 International

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Collections

Faculty of Science and Engineering