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    Bioactive potential and topical formulation of black rice (Oryza sativa) extract compared with ferulic acid and arbutin
    (Elsevier, 2026) Dikmen Küçük, Sibel; Jabet, Paul; Groso, Anthony; Collet, Guillaume; Daniellou, Richard; Kurtay, Emine
    Black rice (Oryza sativa L.) is a rich source of phenolics and flavonoids, making it a candidate ingredient for dermocosmetic applications. This study aimed to evaluate the bioactive potential of an ethanolic black rice extract as a supportive ingredient by comparing its antioxidant capacity, tyrosinase inhibitory activity, and cytocompatibility with two established references, ferulic acid and arbutin, and by developing a stable topical formulation. The extract, containing 141.23 +/- 7.06 mg GAE/g phenolics and 96.75 +/- 4.84 mg QE/g flavonoids, exhibited a moderate total antioxidant capacity (46 mu mol TE mL-1). At a non-cytotoxic concentration (<= 0.1 % v/ v) that maintained over 90 % viability in HaCaT keratinocytes, its tyrosinase inhibition was limited compared to the reference compounds. A topical gel formulated with the extract exhibited acceptable physicochemical properties and remained stable in accelerated stability tests simulating a 2-year shelf life, showing no significant change in appearance, pH, viscosity, or microbiological quality. While the direct depigmenting effect was limited, black rice extract displays a positive biocompatibility and stability profile, supporting its potential role as a multifunctional, natural supporting ingredient in cosmetic formulations for oxidative balance and skincare. This provides a scientific basis for the future development of safe, naturally sourced skincare products containing black rice extract.
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    Cosmeceutical and Dermatological Potential of Shiitake Mushroom (Lentinula edodes) Extract
    (Wiley, 2026) Dikmen Küçük, Sibel; Jabet, Paul; Groso, Anthony; Collet, Guillaume; Daniellou, Richard; Karadeniz, Beste
    Background: Shiitake mushroom (Lentinula edodes) contains polysaccharides, phenolics, and beta-glucans known for their antioxidant and nutraceutical properties; however, its dermatological applications remain limited. Objective: This study aimed to evaluate the antioxidant potential, enzyme inhibition activities, and cytotoxicity of freeze-dried Shiitake extract and to develop and characterize a topical cream formulation containing the extract for potential cosmetical and dermatological use. Methods: Shiitake mushrooms were extracted with 75% ethanol and freeze-dried. Antioxidant capacity was assessed using a total antioxidant assay. Elastase, collagenase, and tyrosinase inhibition activities were evaluated using fluorometric and spectrophotometric assays. Cytotoxicity was tested on HaCaT human keratinocytes using the AlamarBlue assay. A topical cream formulation containing the shiitake extract was prepared, and its pH, viscosity, density, and stability were assessed through accelerated stability tests. Results: The extract showed moderate antioxidant capacity (107 mu M Trolox equivalent). It inhibited elastase activity by 51.99% and induced a concentration-dependent suppression of collagenase activity, reducing measurable enzyme activity to levels below the detection limit of the assay at higher concentrations. No significant tyrosinase inhibition was observed. Cytotoxicity assays confirmed that the extract was non-toxic, maintaining > 90% HaCaT viability across all tested concentrations. The formulated cream exhibited skin-compatible pH (approximate to 5.5), suitable viscosity, homogeneous texture, and remained stable without phase separation or microbial growth under accelerated aging conditions. Conclusion: Shiitake extract appears to be a safe and naturally derived bioactive ingredient, exhibiting notable elastase and collagenase inhibitory activities and demonstrating promising potential for incorporation into anti-aging and nutraceutical skin-care formulations.
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    Cosmetic potential of Ganoderma lucidum (Reishi) extract in a topical cream formulation
    (Wiley, 2026) Dikmen Küçük, Sibel; Jabet, Paul; Groso, Anthony; Collet, Guillaume; Daniellou, Richard; Karadeniz, Beste
    Objective The primary objective of this study was to investigate the biological activities of freeze-dried Ganoderma lucidum (Reishi) extract obtained from hazelnut pruning waste and to compare its antioxidant, tyrosinase inhibitory and cytotoxic properties with two widely used cosmetic actives-argireline peptide and alpha-arbutin. Additionally, the study aimed to develop a topical cream formulation containing Reishi extract and to assess its microbiological safety, preservative efficacy and physicochemical stability under controlled environmental conditions. By integrating bioactivity evaluation with formulation performance, the research sought to determine the potential applicability of Reishi extract as a natural and multifunctional cosmetic ingredient suitable for anti-aging and skin-brightening applications.Methods The antioxidant capacity of Reishi extract, argireline peptide and alpha-arbutin was determined using a copper(II)-based total antioxidant capacity assay. Tyrosinase inhibitory activity was measured with human tyrosinase sourced from MNT-1 melanoma cells, while cytotoxicity and safe dose limits were determined in HaCaT human keratinocyte cells via the AlamarBlue (R) method. A topical cream formulation was prepared using a multi-phase emulsification technique and characterized physicochemically. Microbiological safety was assessed according to Turkish Cosmetic Regulations, and preservative efficacy was determined through challenge testing. Stability assessments included temperature cycling, long-term storage at different temperatures and centrifugation tests, monitoring visual, physicochemical and microbiological parameters over a three-month period.Results Reishi extract demonstrated 861 mu mol TE/g antioxidant activity, 30% tyrosinase inhibition and a broader safety margin compared with argireline peptide and alpha-arbutin, which exhibited cytotoxicity at lower concentrations. The formulated cream retained a skin-compatible pH and stable viscosity, while showing no signs of phase separation, colour change or integrity loss under all storage conditions. Microbiological analysis confirmed microbial counts below regulatory limits, and challenge testing revealed rapid log reductions in all tested microorganisms, satisfying the acceptance criteria for preservative efficacy. Stability studies supported the physical robustness and microbiological safety of the final product throughout the evaluation period.Conclusion Overall, the findings highlight Reishi extract as a bioactive-rich, safe and stable natural ingredient with strong potential for incorporation into cosmetic formulations. Its antioxidant performance, moderate tyrosinase inhibition and compatibility within the cream matrix support its use in multifunctional anti-aging and skin-brightening products. Objectif L'objectif principal de cette & eacute;tude & eacute;tait d'& eacute;tudier les activit & eacute;s biologiques de l'extrait de Ganoderma lucidum lyophilis & eacute; (Reishi) obtenu & agrave; partir des d & eacute;chets d'& eacute;lagage des noisettes et de comparer ses propri & eacute;t & eacute;s antioxydantes, inhibitrices de la tyrosinase et cytotoxiques avec deux actifs cosm & eacute;tiques largement utilis & eacute;s : un peptide d'argireline et d'alpha-arbutine. Par ailleurs, l'& eacute;tude visait & agrave; d & eacute;velopper une formulation de cr & egrave;me topique contenant de l'extrait de Reishi et & agrave; & eacute;valuer sa s & eacute;curit & eacute; microbiologique, son efficacit & eacute; de conservation et sa stabilit & eacute; physicochimique dans des conditions environnementales contr & ocirc;l & eacute;es. En int & eacute;grant l'& eacute;valuation de la bioactivit & eacute; & agrave; la performance de la formulation, la recherche a cherch & eacute; & agrave; d & eacute;terminer l'applicabilit & eacute; potentielle de l'extrait de Reishi en tant qu'ingr & eacute;dient cosm & eacute;tique naturel et multifonctionnel adapt & eacute; aux applications anti-& acirc;ge et d'& eacute;claircissement de la peau.M & eacute;thodes La capacit & eacute; antioxydante de l'extrait de Reishi, d'un peptide d'argireline et d'arbutine a & eacute;t & eacute; d & eacute;termin & eacute;e & agrave; l'aide d'un dosage de la capacit & eacute; antioxydante totale & agrave; base de cuivre(II). L'activit & eacute; inhibitrice de la tyrosinase a & eacute;t & eacute; mesur & eacute;e avec la tyrosinase humaine provenant des cellules de m & eacute;lanome MNT-1, tandis que la cytotoxicit & eacute; et les limites de dose s & ucirc;re ont & eacute;t & eacute; d & eacute;termin & eacute;es dans les cellules k & eacute;ratinocytaires humaines HaCaT par la m & eacute;thode AlamarBlue (R). Une formulation de cr & egrave;me topique a & eacute;t & eacute; pr & eacute;par & eacute;e & agrave; l'aide d'une technique d'& eacute;mulsification multiphase et caract & eacute;ris & eacute;e sur le plan physicochimique. La s & eacute;curit & eacute; microbiologique a & eacute;t & eacute; & eacute;valu & eacute;e conform & eacute;ment aux r & eacute;glementations turques en mati & egrave;re de cosm & eacute;tiques, et l'efficacit & eacute; des conservateurs a & eacute;t & eacute; d & eacute;termin & eacute;e par des tests de provocation. Les & eacute;valuations de la stabilit & eacute; comprenaient des cycles de temp & eacute;rature, une conservation & agrave; long terme & agrave; diff & eacute;rentes temp & eacute;ratures et des tests de centrifugation, ainsi qu'une surveillance des param & egrave;tres visuels, physico-chimiques et microbiologiques sur une p & eacute;riode de trois mois.R & eacute;sultats L'extrait de Reishi a d & eacute;montr & eacute; une activit & eacute; antioxydante de 861 mu mol TE/g, une inhibition de 30% de la tyrosinase, et une marge de s & eacute;curit & eacute; plus large par rapport au peptide d'argireline et & agrave; l'arbutine, qui ont montr & eacute; une cytotoxicit & eacute; & agrave; des concentrations plus faibles. La cr & egrave;me formul & eacute;e a conserv & eacute; un pH compatible avec la peau et une viscosit & eacute; stable, tout en ne montrant aucun signe de s & eacute;paration de phase, de changement de couleur o L'analyse microbiologique a confirm & eacute; des num & eacute;rations microbiennes inf & eacute;rieures aux limites r & eacute;glementaires, et les tests de provocation ont r & eacute;v & eacute;l & eacute; des r & eacute;ductions logarithmiques rapides de tous les micro-organismes test & eacute;s, satisfaisant aux crit & egrave;res d'acceptation pour l'efficacit & eacute; des conservateurs. Les & eacute;tudes de stabilit & eacute; ont confirm & eacute; la robustesse physique et la s & eacute;curit & eacute; microbiologique du produit final tout au long de la p & eacute;riode d'& eacute;valuation.Conclusion Dans l'ensemble, les r & eacute;sultats soulignent que l'extrait de Reishi est un ingr & eacute;dient naturel bioactif, s & ucirc;r et stable, avec un fort potentiel d'incorporation dans les formulations cosm & eacute;tiques. Sa performance antioxydante, son inhibition mod & eacute;r & eacute;e de la tyrosinase et sa compatibilit & eacute; au sein de la matrice de la cr & egrave;me favorisent son utilisation dans des produits multifonctions anti-& acirc;ge et & eacute;claircissants.
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    Effect of Bacterial Nanocellulose and Plant-Containing Facial Serum on Hyperpigmentation in in-vitro Conditions
    (North Carolina State Univ Dept Wood & Paper Sci, 2024) Dikmen Küçük, Sibel; Groso, Anthony; Collet, Guillaume; Daniellou, Richard; Caliskan, Ufuk Koca
    This study investigated the effect of some herbal extracts, such as licorice root, white mulberry leaf, green tea leaf, and grape seed, with a combination of bacterial nanocellulose and some bioactive materials, such as ascorbic acid, niacinamide, hexylresorcinol, and alpha-arbutin, on treatment of hyperpigmentation. The effect of the prepared emulsions on hyperpigmentation was revealed by analyzing their tyrosinase inhibition properties, their ability to stop melanin production, or their properties of whitening the brown spot on the skin. In addition to the physicochemical properties of the 5 different emulsions obtained, tyrosinase, collagenase, and elastase enzyme activities, antioxidant properties, cytotoxicity, and microbiological analyzes were performed by cell-culture modelling. Finally, a dermocosmetic facial serum was designed that is compatible with skin pH, is homogeneously mixed, has good spreading properties, does not cause any microbiological growth, does not inhibit elastase activity while stimulating collagenase activity, reduces melanin production by inhibiting the tyrosinase enzyme, and does not have any toxic effects.
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    Queen bee larvae (Apis mellifera) as a novel bioactive matrix: tyrosinase inhibition, compositional analysis, and formulation evaluation
    (Taylor&Francis, 2026) Dikmen Küçük, Sibel; Jabet, Paul; Groso, Anthony; Collet, Guillaume; Daniellou, Richard; Kekecoglu, Meral; Onder, Elif
    Queen bee larvae (QBL), a by-product of Apis mellifera royal jelly production, represent an underexplored protein-rich biological matrix with enzyme-modulatory bioactivity. This study provides the first systematic characterisation of lyophilised QBL through compositional profiling, tyrosinase inhibitory activity, cytocompatibility assessment, and topical carrier stability evaluation. Compositional analysis (AOAC/ISO-accredited methods) revealed a proteindominant matrix (55.19 g/100 g) rich in essential amino acids, B-group vitamins, vitamins C, D3 and E, and minerals (Mg 1566 mg/ kg; Ca 676.6 mg/kg), with total antioxidant capacity of 312.1 ?M Trolox equivalents. QBL demonstrated concentration-dependent human tyrosinase inhibition, reaching 75.7 ± 2.5% at 1000 ?g/mL. HaCaT keratinocyte viability exceeded 80% across all concentrations at 24 h and 48 h. A QBL-incorporated model gel maintained physicochemical integrity and microbiological stability over three months. These findings establish QBL as a biocompatible, protein-dominant natural matrix with tyrosinase-modulatory and antioxidant properties, warranting further investigation as a bioactive natural product.