International Journal of Cosmetic Science最新文献

Objective: Rhizospheric microorganisms play a crucial role in plant vitality by contributing to nutrient supply and overall plant health. This research focused on a specific yeast isolated from the rhizosphere of Rosa hybrid delflobla and aimed to investigate if a resulting natural active ingredient can have cosmetic benefits, particularly concerning NAD+, a cofactor known to play a vital role in skin longevity.

Methods: The yeast Aureobasidium pullulans, sampled in the rhizosphere of Rosa hybrid delflobla, was processed to generate a natural active ingredient (INCI: Aureobasidium pullulans ferment). The efficacy of this active ingredient was investigated on NAD+ (nicotinamide adenine dinucleotide) synthesis, a crucial molecule playing a fundamental role in energy metabolism and a multitude of key cellular processes, as well as on cutaneous barrier function and related skin benefits.

Results: The results of this study demonstrate that the Aureobasidium pullulans ferment increases the NAD+/NADH ratio. Moreover, the expression and synthesis of epidermal differentiation and cohesion markers are stimulated with this natural active ingredient, resulting in an improved barrier function. Clinical results demonstrate that the Aureobasidium pullulans ferment smooths skin microrelief and enhances complexion radiance.

Conclusion: Altogether, these results reveal that the active ingredient obtained from the Rosa hybrid delflobla rhizosphere (INCI: Aureobasidium pullulans ferment) has highly interesting potential to improve skin resilience and longevity.

Aims: The physicochemical stability of cosmetic emulsions is crucial for successful commercialization and consumer satisfaction. This study presents an innovative protocol that combines rheology, turbidimetry and granulometry to predict emulsion stability more efficiently.

Materials and methods: Industrial emulsions, including some commercial products, were selected to compare stable and unstable samples with minimal formulation differences. Granulometry, turbidimetry and rheology assessments were used to evaluate physical and structural properties. The collected data were subjected to advanced statistical analysis using experimental design methods.

Results: Granulometry, turbidimetry and rheology each effectively distinguished stable from unstable emulsions. Stable emulsions maintained a constant median particle size, while unstable samples exhibited significant increases. Viscosity changes were observed only in unstable emulsions. Turbidimetry showed a Turbiscan Stability Index (TSI) >3 for unstable emulsions and <3 for stable ones. Notably, this combined protocol identified instability as early as 8 days-much faster than standard ISO methods, which require up to 30 days.

Conclusions: Integrating granulometry, turbidimetry and rheology with advanced data analysis enables a rapid, reliable and sensitive prediction of cosmetic emulsion stability. This approach overcomes the limitations of traditional testing by allowing earlier detection of instability, improving formulation development, quality control and time-to-market. Future work will assess the protocol's applicability to a wider range of emulsion types.

Objective: This study investigates the impact of hydrophobic Natural Eutectic Solvents (NES) on the physicochemical and sensory characteristics of cosmetic creams. The aim is to assess their potential as innovative, sustainable ingredients introduced directly into the oily phase of an oil-in-water emulsion prior to emulsification.

Methods: Four NES formulations, composed of natural components such as caprylic acid, lauric acid, menthol and 1,3-propanediol were incorporated at 10% wt. into a COSMOS-compliant cream chassis. The resulting creams were evaluated for physical stability using static multiple light scattering (Turbiscan®), rheological behaviour via shear and oscillatory tests, and sensory attributes through a trained panel.

Results: Among the four NES-containing creams, three formulations demonstrated satisfactory physical stability over 30 days under accelerated ageing conditions. Menthol-based NES induced phase separation, correlating with increased droplet size and higher Turbiscan Stability Index values. All creams exhibited shear-thinning behaviour, with viscosity profiles and yield stress varying depending on NES composition. Sensory analysis revealed that NES significantly influenced key attributes such as odour intensity, spreading, pick-up and firmness.

Conclusion: Hydrophobic NES can be successfully integrated into the internal phase of cosmetic creams, influencing both their structural and sensory properties. These findings highlight their potential as multifunctional and eco-friendly ingredients in cosmetic formulation, supporting the development of more sustainable, more performant skincare products.

Objective: Sensitive skin is typically characterized by dryness, reactivity and inflammation, often associated with a compromised skin barrier and an imbalanced microbiome. This study aims to investigate the effects and mechanisms of fermented tea seed oil in improving sensitive skin, particularly focusing on the skin lipid barrier and microbiome.

Methods: Tea seed oil was fermented using biotechnology, and its lipid components were analysed both before and after fermentation. A double-blind, randomized, half-face controlled clinical trial was conducted on 25 Chinese young women with sensitive skin. Participants used a moisturizer containing 5% fermented tea seed oil or a base moisturizer for 4 weeks. Non-invasive methods were used to measure physiological parameters. Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) and high-throughput gene sequencing technologies were employed to analyse skin lipids and the microbiome.

Results: Fifty-three differential lipids were identified by comparing the lipid profiles of tea seed oil before and after fermentation. The most significant increase was observed in DHA-CoA, which has the potential to improve skin lipid metabolism and enhance the skin barrier. The participants showed significant improvements in skin hydration, redness reduction and facial wrinkles. Lipidomics analysis revealed notable changes in the skin lipid profile before and after treatment, with 41 and 15 differentially expressed lipids identified in the test and control groups, respectively. Microbiome results indicated no significant alterations in the diversity or abundance of skin microbiota after treatment. Nevertheless, the composition of the skin microbiota demonstrated a beneficial shift, with Propionibacterium acnes being suppressed while Streptococcus increased. These microbial changes are associated with skin barrier repair as well as sensitivity and inflammation.

Conclusion: Fermented tea seed oil demonstrates notable clinical benefits for sensitive skin. It effectively regulates lipid metabolism and the composition of skin microbiota, thereby strengthening the lipid barrier and reducing the risk of potential inflammation. The increased presence of DHA-CoA in the fermented tea seed oil may serve as a key molecular contributor to its improved reparative efficacy.

Objective: To address the current lack of standardized tools for evaluating hair appearance in the beauty industry, this study presents a robust and accessible method for objectively quantifying hair fibre orientation using two-dimensional discrete Fourier transform (2D-DFT).

Methods: We analysed hair images of 120 Japanese women using 2D-DFT and extracted the principal orientation angle and anisotropy index by fitting an ellipse to the directional Fourier spectrum. The robustness of the method at the image scale was tested by evaluating its performance across various image resolutions.

Results: The proposed method accurately quantified hair orientation and showed consistent performance across differing image scales provided that individual hair fibres were visually distinguishable. As the method requires only standard digital images and basic computational processing, it is well suited for practical applications.

Conclusion: Our 2D-DFT-based approach offers a simple yet robust framework for analysing overall hair orientation. Although further validation is required for different hair types and local orientation analyses, this method provides a foundation for objective evaluation of hair appearance in cosmetic diagnostics and hair science research.

Objectives: Oat lipids are rich in ceramides. In this investigation, we analysed the delivery of a specific Oat Lipid Extract derived from Avena sativa, comprising 'skin identical' ratios of fatty acids, ceramides and cholesterol/sterol. This investigation is the first reported investigation of oat lipids utilizing Raman spectroscopy for the identification of oat ceramides from A. sativa supported by Lipbarvis®, transmission electron microscopy and immunofluorescence analysis.

Methods: Oil lipid class compositions were determined by single-dimension double-development high-performance thin-layer chromatography. Ceramide class profiling was carried out using liquid chromatography with tandem mass spectrometry. Raman spectra of lipids were obtained by confocal Raman spectroscopy and immunostaining on human skin explants following treatment for 5 days. Length of lipid lamellae was determined using Lipbarvis® transmission electron microscopy followed by immuno-histochemical analysis of hyaluronic acid and ceramides, on human skin following treatment for 56 days. Measurement of skin roughness (PRIMOS) and hydration (corneometer) were performed following treatment for 56 days.

Results: Gas-liquid chromatography and high-performance thin-layer chromatography profiling of Oat Lipid Extract, revealed that of the ceramide classes identified, skin identical sphingosine and phytosphingosine bases were present. Oat Lipid Extract has a typical total polar lipid content of 40 g kg^-1 of which 4 g kg^-1 ceramides, comprised ceramides/hydroxyceramides, gycosyl inositol phosphoryl ceramides and glucosylceramides. Raman profiling of Oat Lipid Extract was well correlated with stratum corneum and viable epidermis lipid profiles. Oat Lipid Extract induced a significant increase in neutral and polar lipid content. Lipbarvis® transmission electron microscopy and immunostaining showed significant increase in the length of the intercellular lipid lamellae and in the amount of hyaluronic acid and ceramides. Oat Lipid Extract significantly reduced skin roughness and increased skin hydration after 56 days of treatment.

Conclusion: Oat ceramides in the form of Oat Lipid Extract can be effectively delivered into the stratum corneum. The preliminary Raman and electron microscopy Lipbarvis® studies have given good insight into the possibility of Oat Lipid Extract mimicking the structure and function of the skin's barrier. The visible effect on the skin was observed with a decrease in skin roughness.

Objective: To develop and evaluate a novel silicone ionic gel (SIG) for personal care applications, designed to deliver enhanced texture, hydration, and compatibility with a wide range of cosmetic ingredients.

Methods: SIG was synthesized by swelling a fatty acid modified silicone elastomer in 68 wt% plant-derived solvent. The gel's architecture was engineered to form flexible, water-accessible channels. Performance was assessed through various complementary techniques including rheological testing, formulation studies, and skin hydration testing.

Results: SIG exhibited solid-like rheology, shear recovery, and surfactant-free incorporation of water and polyols. SIG-based formulations improved skin hydration by ~10% over PEG-based silicone gels. Demonstrated broad compatibility with hydrophilic and hydrophobic ingredients. Showed superior pigment dispersion without surface treatment, confirmed via optical microscopy.

Conclusions: SIG is a multifunctional gel platform offering unique texture, long-lasting sensory effects, enhanced moisturization, and formulation flexibility. Its compatibility with diverse cosmetic ingredients and ability to host structured water make it a promising candidate for next-generation skincare and cosmetic products.

Although some studies suggest the benefits of clay minerals in hair treatments, limited research has addressed their effects on the mechanical properties of hair fibres. This study investigates the incorporation of two commercial clays (designated A and B) into solid shampoo and conditioner formulations and evaluates their impact on the mechanical performance of hair fibres. X-ray fluorescence spectroscopy (XRF) analysis of the clays revealed a high silica content. X-ray diffraction (XRD) analysis identified montmorillonite and nontronite phases in clay A, characterizing it as bentonite. In contrast, clay B exhibited a predominant muscovite phase with secondary phases of illite and chlorite. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of typical vibrational modes associated with these clay minerals. UV-VIS spectroscopy showed strong absorption in the ultraviolet region for both clays. Formulations were developed with clay concentrations of 0.5%, 1.5%, and 3.0%, alongside a clay-free control. The addition of clays significantly enhanced the mechanical strength of the hair fibres, particularly clay B, which yielded a 94% improvement at 3.0% concentration. Combing force measurements also improved, indicating that the tested concentration effectively reduced frizz. Gloss measurements showed excellent enhancement across all formulations, with clay B increasing specular reflection by 56% at 3.0%. Overall, these findings demonstrate a promising potential for commercial clays to improve the mechanical and aesthetic properties of hair when incorporated into cosmetic formulations.

Background: In recent years, the psychological dimension of skin health has attracted increasing research interest, with established skin-related wellbeing metrics providing valuable insights for various conditions in clinical dermatology. This growing focus underscores the importance of developing sensitive, well-validated tools to better understand the emotional impact of skin health and appearance in healthy populations. The present article details the development and validation of such a metric, the SkinCARE Questionnaire (Condition and Affective Response Evaluation), and its relation to self-reported psychological stress and sleep health.

Method: 1184 participants (African American: n = 396, Hispanic: n = 392, Caucasian: n = 396; 886 females) completed the SkinCARE questionnaire, Sleep Health Index (SHI) and Perceived Stress Scale (PSS). The SkinCARE data was randomly divided into two equal samples for analysis: Sample 1 for exploratory factor analysis and Sample 2 for confirmatory factor analysis.

Results: Exploratory factor analysis supported a 24-item three-factor solution. Factor 1, Skin Social Impact, comprised 16 items that related primarily to how skin health impacted relationships with others and daily functioning. Factor 2, Skin Reactivity, comprised a further six items related to product reactions and skin breakouts. Factor 3, General Confidence, comprised a final 2 items. The three-factor structure was supported by confirmatory factor analysis. Further analysis demonstrated positive associations between good skin wellbeing, good quality sleep and low levels of stress.

Conclusion: The present scale is the first validated instrument designed to specifically measure the impact of skin health on emotional wellbeing in healthy populations. These data confirm the association between skin health and psychological wellbeing, and also a link to psychological wellbeing indicators. Future research should leverage the SkinCARE Questionnaire to examine and describe the effects of cosmetic skincare products on wellbeing.

Objective: Niacinamide is a well-established ingredient known for reducing hyperpigmentation by inhibiting melanosome transfer from melanocytes to keratinocytes. This study aimed to explore the potential synergistic effects of niacinamide and low pH in melanogenesis pathways and their impact on skin hyperpigmentation in clinical trials.

Methods: In vitro experiments were conducted using human melanocyte and/or keratinocyte cultures to investigate the effects of niacinamide at varying pH levels (neutral pH 7 and low pH 2.5-4). Melanin synthesis, melanocyte dendricity, melanosome transfer and melanosome degradation were assessed. Transcriptome analysis was performed to identify gene expression changes in human melanocytes. Additionally, vehicle-controlled facial clinical trials were conducted among Caucasian and Chinese females to evaluate the effects of niacinamide formulations at neutral and low pH.

Results: Niacinamide in neutral pH solutions and simple low pH solutions (without niacinamide) did not inhibit melanin synthesis or melanocyte dendricity, as expected. However, niacinamide in low pH solutions significantly inhibited both, indicating a synergistic interaction. Enhanced suppression of melanosome transfer and degradation was also observed, although these effects appeared to be additive to the effects of neutral pH niacinamide. Transcriptome analysis revealed downregulation of genes and pathways associated with melanogenic cytokine signalling, melanin biosynthesis, melanocyte dendricity and melanosome transfer for niacinamide in low pH formulation, but not niacinamide in neutral pH or simple low pH formulations (without niacinamide), further supporting the synergistic effect. A 4-week clinical trial among Caucasian females using 2% niacinamide formulation at pH 2.5 revealed a marked reduction in the appearance of facial spots compared to 2% niacinamide neutral pH or vehicle formulations. Similarly, an 8-week clinical trial conducted with Chinese females using 5% niacinamide formulation at pH 4 demonstrated significantly greater efficacy in both facial spot reduction and skin brightening in appearance than neutral pH niacinamide and vehicle formulations.

Conclusion: Our series of in vitro and clinical studies revealed groundbreaking findings on the role of pH modulation in enhancing the efficacy of niacinamide for hyperpigmentation reduction. By elucidating the synergistic mechanisms involved, this research paves the way for developing more effective treatments aimed at achieving a brighter and more uniform complexion safely.