Natural products in cosmetics

Protonation State of a Bioactive Compound Regulates Its Release from Lamellar Gel-Phase Bilayers

Lamellar gel networks (LGNs) in personal care or pharmaceutical lotions and creams provide an opaque cream appearance and a creamy texture to these products. Within the LGNs, the lamellar gel (Lβ) phase composed of regularly spaced bilayers of surfactants and long-chain fatty alcohols is predominately responsible for the unique rheological properties of the LGNs. To extend the shelf life of LGN-containing products, bioactive compounds with antimicrobial properties are often incorporated into the formulation. However, how the protonation state of the bioactive compounds regulates their release from the Lβ-phase bilayers is currently unknown. Using molecular dynamics simulations, we found that the protonated (neutral) form of cinnamic acid, a common antimicrobial food additive, has a retention ratio higher than that of its deprotonated (charged) counterpart in the Lβ-phase bilayer. From free energy calculations, we determined that not only is the protonated molecule more stable in the hydrophobic interior of the bilayer but also the formation of hydrogen-bonded dimers significantly enhances its stability within the bilayer. Thus, the protonation state has a profound impact on bioavailability of the compounds. Our results also highlight the importance of considering possible oligomeric states of molecules when performing calculations to estimate the permeability of molecules within various bilayers.

New Insights into Trace Element Accumulation in Kernels of Two Algerian Populations of Argan (Argania spinosa (L.) Skeels): An Endangered Endemic Tree

Argan is one of the valuable oilseed trees in the Northwest Africa area, with important ecological and socioeconomic benefits; however, information underlying its elemental status remains absent . The current work was performed for the first time to quantify the mineral status of Argania spinosa kernels collected from two different geographic Algerian regions (Mostaganem and Tindouf). Elemental investigation (As, Br, Ca, Ce, Co, Cr, Fe, K, La, Na, Rb, Sb, Sc, Sm, Th, and Zn) was performed using neutron activation analysis (NAA). Two standard reference materials from the National Research Center for certified reference materials (China), namely, CRM-GBW 07605 (GSV-4 tea leaves), and the National Institute of Standards and Technology (USA), namely, NIST (SRM 1573a, tomato leaves), were used to ensure precision and validation of NAA measurements. A computational calculation of data including principal component analysis (PCA) and Pearson correlation coefficient (r) was applied. The extents of essential elements in Mostaganem kernels were found to be in the order of K (7185 μg g-1) > Ca (2079 μg g-1) > Na (205 μg g-1) > Fe (84.33 μg g-1) > Zn (73.41 μg g-1) > Cr (0.66 μg g-1) > Co (0.035 μg g-1), whereas the overall order of these elements in Tindouf kernels was K (7206 μg g-1) > Ca (3725 μg g-1) > Fe (114.69 μg g-1) > Zn (67.37 μg g-1) > Na (56.29 μg g-1) > Cr (0.54 μg g-1) > Co (0.11 μg g-1). PCA results revealed that Tindouf population was highly loaded with Br, Cr, Cu, Mn, Sr, V, and Zn, while Mostaganem population was associated only with Ce and Sm contents. These findings can be useful for making new formulations for cosmetic and culinary usage and contribute to the nutritional database and food safety.

Evaluating the Efficacy and Safety of Alpha-Hydroxy Acids in Dermatological Practice: A Comprehensive Clinical and Legal Review

The global market for alpha-hydroxy acids (AHAs) is undergoing significant expansion, propelled by increasing demand for skincare products that address aging and environmental damage. This review focuses on the dermatological applications of AHAs, particularly in cosmetic formulations like chemical peels. We have identified that AHAs, such as glycolic and lactic acids, enhance skin rejuvenation by promoting apoptosis in skin cells, boosting collagen and elastin synthesis, and improving skin texture and luminosity. Our comprehensive analysis reveals a nuanced understanding of AHAs' effectiveness across various skin types and conditions, demonstrating their broad utility in treating conditions like acne, hyperpigmentation, and photoaging. However, the optimal concentrations for therapeutic efficacy with minimal side effects are yet to be precisely defined, necessitating further research. Regulatory compliance is underscored as essential for the safe application of AHAs in cosmetics, with international guidelines recommending specific concentrations and pH levels to minimize potential skin irritation. In Conclusion, the review highlights the effectiveness of AHAs in cosmetic dermatology, emphasizing the necessity for continued research and rigorous regulatory adherence to maximize their safe and beneficial application worldwide.

Synthesis and Investigation of Biological Activity of New Betulonic Acid Derivatives Containing 1,2,3-Triazole Fragments

The results of this study showed that the compounds synthesized by the authors have significant potential due to their antibacterial and cytotoxic properties. The apparent antibacterial activity demonstrated by the compounds suggests that they are active antimicrobial agents against common microbial pathogens that cause various socially significant infectious diseases. Compound 6 showed pronounced antimicrobial activity against the Gram-positive test strain Staphylococcus aureus ATCC 6538, and compound 7 demonstrated pronounced antimicrobial activity against the Gram-negative test strain Escherichia coli ATCC 25922 (MIC = 6.3 µg/mL). This allowed us to consider these compounds to have great potential.

"Edible Beauty": The Evolution of Environmentally Friendly Cosmetics and Packaging

The cosmetics industry plays a significant role in the global economy and consumer lifestyles. Its dynamic and adaptable characteristics make it a key player worldwide. The cosmetics industry generates enormous profits globally, injecting billions of dollars into the world's economy each year. The industry's marketing efforts, product launches, and trends influence consumer behavior and perceptions of beauty, contributing to cultural dialogues and societal norms. This study, conducted with a rigorous bibliometric and systematic literature review, offers a comprehensive overview of recent progress in edible cosmetics. The "skincare you can eat" is an innovative branch of cosmetics that employs food co-products and by-products to create edible skincare and hair products and edible packaging materials to advance human well-being and sustainability while honoring the ecological boundaries of our planet. Nutrients and antioxidants derived from organic waste are used in cosmetics and packaging. Some doubts remain about the capacity of edible packaging to be attractive to consumers and offer a reasonable shelf life for cosmetics, and also about safety. It is desirable for the authorities to guarantee consumer health through carefully regulating labeling requirements and good manufacturing practices for cosmetics and edible packaging.

Virtual screening of natural products to enhance melanogenosis

Natural products have long been an important source of inspiration for medicinal chemistry and drug discovery. In the cosmetic field, they remain the major elements of the composition and serve as marketing asset. Recent research showed the implication of salt-inducible kinases on the melanin production in skin via MITF regulation. Finding new potent modulators on such target could open the way to several cosmetic applications to attenuate visible signs of photoaging and improve the tan without sun. Since virtual screening can be a powerful tool for detecting hit compounds in the early stages of a drug discovery process, we applied this method on salt-inducible kinase 2 to discover potential interesting compounds. Here, we present the different steps from the construction of a database of natural products, to the validation of a docking protocol and the results of the virtual screening. Hits from the screening were tested in vitro to confirm their efficiency and results are discussed.

Exploring Phenolic Compounds in Crop By-Products for Cosmetic Efficacy

Phenolic compounds represent a group of secondary metabolites that serve essential functions in plants. Beyond their positive impact on plants, these phenolic metabolites, often referred to as polyphenols, possess a range of biological properties that can promote skin health. Scientific research indicates that topically using phenolics derived from plants can be advantageous, but their activity and stability highly depend on storage of the source material and the extraction method. These compounds have the ability to relieve symptoms and hinder the progression of different skin diseases. Because they come from natural sources and have minimal toxicity, phenolic compounds show potential in addressing the causes and effects of skin aging, skin diseases, and various types of skin damage, such as wounds and burns. Hence, this review provides extensive information on the particular crops from which by-product phenolic compounds can be sourced, also emphasizing the need to conduct research according to proper plant material storage practices and the choice of the best extracting method, along with an examination of their specific functions and the mechanisms by which they act to protect skin.

Inhibitory Effects of Fermented Sprouted Oat Extracts on Oxidative Stress and Melanin Overproduction

Hyperpigmentation occurs due to irregular secretion of melanin pigment in the skin. This can affect quality of life depending on its severity, so prevention and management are essential. Oats (Avena sativa L.), a grain consumed worldwide, are known to offer improved health benefits upon germination and fermentation. This study is aimed to investigate the protective effects of lactobacilli-fermented sprouted oat extracts on oxidative stress and melanin overproduction in vitro. The anti-melanogenic effect was investigated using melanin content and tyrosinase activity assays in B16F10 cells, as well as a mushroom tyrosinase-based enzyme inhibition assay. The results showed that L. casei-fermented oat extracts were the most effective for reducing melanin formation by reducing the mRNA expression of microphthalmia-associated transcription factor, tyrosinase, and tyrosinase-related protein 2. Furthermore, L. casei fermentation was effective in improving the total phenolic, flavonoid, and avenanthramide A contents of sprouted oat extracts. The results also demonstrated the antioxidant effects of L. casei-fermented sprouted oat extracts in promoting DPPH radical-scavenging activity, superoxide dismutase-like activity, and reduction in reactive oxygen species levels. Overall, the findings indicate that fermented sprouted oat extracts are promising candidates for antioxidant and anti-hyperpigmentation treatments.

GC-MS analysis and anti-oxidant activity of bioactive compounds of Simarouba glauca leaf extracts

The aim of this study is to analyse the phytochemical composition, anti-oxidant activity, FT-IR and GC-MS analysis of Simarouba glauca leaf extracts. The chloroform extract exhibited highest T.P.C. (139.82 ± 0.06 mg/g GAE) and highest T.F.C. (41.95 ± 0.50 mg/g QE). The GC-MS analysis confirmed the presence of ten compounds in acetone extract and twenty-two compounds in methanol extract. The GC-MS analysis of acetone fraction showed the major peaks such as Glycerine (13.20%), 1,1,1-trichloro-2-methyl-2-propanol (8.92%), Cyclohexanol,2-methyl-5-(1-methylethenyl)- (6.09%), Tetradecane, 2,6,10-trimethyl (7.68%) and Phytol (7.53%). Some of these compounds exhibit anti-oxidant activities. GC-MS analysis of methanol fraction exhibited the presence of following compounds: Undecane (8.52%), 2,3-Trimethylene-4-pyrone (1.79%), cis-Sinapyl alcohol (2.33%) and Umckalin (1.19%). The acetone and methanol fractions exhibited higher percentage of inhibition in DPPH assay. The overall results of this study indicate that the acetone and methanol fractions have been demonstrated to be efficacious against various diseases.

Optimized carotenoid production and antioxidant capacity of Gordonia hongkongensis

The current emphasis within the cosmetic market on sustainable ingredients has heightened the exploration of new sources for natural, active components. Actinomycetota, recognized for producing pigments with bioactive potential, offer promising functional cosmetic ingredients. This study aimed to optimize pigment and antioxidant metabolite production from the Gordonia hongkongensis strain EUFUS-Z928 by implementing the Plackett-Burman experimental design and response surface methodology. Extracts derived from this strain exhibited no cytotoxic activity against human primary dermal fibroblast (HDFa, ATCC® PCS-201-012™, Primary Dermal Fibroblast; Normal, Human, Adult). Eight variables, including inoculum concentration, carbon and nitrogen source concentration, NaCl concentration, pH, incubation time, temperature, and stirring speed, were analyzed using the Plackett-Burman experimental design. Subsequently, factors significantly influencing pigment and antioxidant metabolite production, such as temperature, inoculum concentration, and agitation speed, were further optimized using response surface methodology and Box-Behnken design. The results demonstrated a substantial increase in absorbance (from 0.091 to 0.32), DPPH radical scavenging capacity (from 27.60% to 84.61%), and ABTS radical scavenging capacity (from 17.39% to 79.77%) compared to responses obtained in the isolation medium. The validation of the mathematical model accuracy exceeded 90% for all cases. Furthermore, liquid chromatography coupled with mass spectrometry (LC-MS) facilitated the identification of compounds potentially responsible for enhanced pigment production and antioxidant capacity in extracts derived from G. hongkongensis. Specifically, six carotenoids, red-orange pigments with inherent antioxidant capacity, were identified as the main enhanced compounds. This comprehensive approach effectively optimized the culture conditions and medium of a G. hongkongensis strain, resulting in enhanced carotenoid production and antioxidant capacity. Beyond identifying bioactive compounds and their potential cosmetic applications, this study offers insights into the broader industrial applicability of these extracts. It underscores the potential of G. hongkongensis and hints at the future utilization of other untapped sources of rare actinomycetes within the industry.

Inhibition of α-melanocyte-stimulating hormone-induced melanogenesis and molecular mechanisms by polyphenol-enriched fraction of Tagetes erecta L. flower

BACKGROUND

The pursuit for safe and efficacious skin-whitening agents has prompted a dedicated exploration of plant-derived compounds. Notably, Tagetes erecta L. flowers have been used as a medicinal extract and possessed in vitro mushroom tyrosinase activity. However, whether polyphenol-enriched fraction extracted from T. erecta L. flowers (TE) regulates melanogenesis within cellular and animal models has not yet been investigated.

PURPOSE

This study aimed to investigate the effect of TE as a prospective inhibitor of melanogenesis.

METHODS

Through advanced UPLC-QTof/MS analysis, the components of TE were analyzed. Anti-melanogenic effects of TE were evaluated in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16F10 melanoma cells by measuring cell viability assay, extracellular and intracellular melanin biosynthesis, cyclic adenosine monophosphate (cAMP) production, and melanogenesis-related gene and protein expression. Zebrafish larvae were employed for in vivo studies, assessing both heart rate and melanogenesis. Furthermore, molecular docking analyses were employed to predict the interaction between TE components and the melanocortin 1 receptor (MC1R). Direct binding activity of TE components to MC1R was compared with [Nle4, d-Phe7]-MSH (NDP-MSH).

RESULTS

TE was found to contain significant phenolic compounds such as patulitrin, quercetagetin, kaempferol, patuletin, and isorhamnetin. This study revealed that TE effectively inhibits melanin biosynthesis in both in vitro and in vivo models. This inhibition was attributed to interference of TE with the cAMP-cAMP response element-binding protein (CREB)-microphthalmia-associated transcription factor (MITF)-tyrosinase pathway, which plays a pivotal role in regulating melanogenesis. Importantly, TE exhibited the remarkable ability to curtail α-MSH-induced melanogenesis in zebrafish larvae without impacting heart rates. Molecular docking analyses predicted that the components of TE possibly interact with the melanocortin 1 receptor, suggesting their role as potential inhibitors of melanin biosynthesis. However, through the direct binding activity compared with NDP-MSH, any TE components did not directly bind to MC1R, suggesting that TE inhibits α-MSH-induced melanogenesis by inhibiting the cAMP-mediated intracellular signaling pathway. The assessment of anti-melanogenic activity, conducted both in vitro and in vivo, revealed that patulitrin and patuletin exhibited significant inhibitory effects on melanin formation, highlighting their potency as major contributors.

DISCUSSION

This investigation demonstrated the considerable potential of TE as a natural remedy endowed with remarkable anti-melanogenic properties. The demonstrated capacity of TE to attenuate melanin production by modulating the cAMP-CREB-MITF-tyrosinase pathway underscores its central role in management of disorders associated with excessive pigmentation. Importantly, the implications of these findings extend to the cosmetics industry, where TE emerges as a prospective and valuable ingredient for the formulation of skin-whitening products. The elucidated interactions between TE components and MC1R not only provide insight into a potential mechanism of action but also elevate the significance of this study. In summary, this study not only contributes to our comprehension of pigmentation-related conditions but also firmly establishes TE as a secure and natural strategy for the regulation of melanin production. The innovative aspects of TE propel it into the forefront of potential interventions, marking a noteworthy advancement in the pursuit of effective and safe solutions for pigmentation disorders.

Pulp or Peel? Comparative Analysis of the Phytochemical Content and Selected Cosmetic-Related Properties of Annona cherimola L., Diospyros kaki Thumb., Cydonia oblonga Mill. and Fortunella margarita Swingle Pulp and Peel Extracts

Fruit peels might be a valuable source of active ingredients for cosmetics, leading to more sustainable usage of plant by-products. The aim of the study was to evaluate the phytochemical content and selected biological properties of hydroglycolic extracts from peels and pulps of Annona cherimola, Diospyros kaki, Cydonia oblonga, and Fortunella margarita as potential cosmetic ingredients. Peel and pulp extracts were compared for their antiradical activity (using DPPH and ABTS radical scavenging assays), skin-lightening potential (tyrosinase inhibitory assay), sun protection factor (SPF), and cytotoxicity toward human fibroblast, keratinocyte, and melanoma cell lines. The total content of polyphenols and/or flavonoids was significantly higher in peel than in pulp extracts, and the composition of particular active compounds was also markedly different. The HPLC-MS fingerprinting revealed the presence of catechin, epicatechin and rutoside in the peel of D. kaki, whereas kaempferol glucoside and procyanidin A were present only in the pulp. In A. cherimola, catechin, epicatechin and rutoside were identified only in the peel of the fruit, whereas procyanidins were traced only in the pulp extracts. Quercetin and luteolinidin were found to be characteristic compounds of F. margarita peel extract. Naringenin and hesperidin were found only in the pulp of F. margarita. The most significant compositional variety between the peel and pulp extracts was observed for C. oblonga: Peel extracts contained a higher number of active components (e.g., vicenin-2, kaempferol rutinoside, or kaempferol galactoside) than pulp extract. The radical scavenging potential of peel extracts was higher than of the pulp extracts. D. kaki and F. margarita peel and pulp extracts inhibited mushroom and murine tyrosinases at comparable levels. The C. oblonga pulp extract was a more potent mushroom tyrosinase inhibitor than the peel extract. Peel extract of A. cherimola inhibited mushroom tyrosinase but activated the murine enzyme. F. margarita pulp and peel extracts showed the highest in vitro SPF. A. cherimola, D. kaki, and F. margarita extracts were not cytotoxic for fibroblasts and keratinocytes up to a concentration of 2% (v/v) and the peel extracts were cytotoxic for A375 melanoma cells. To summarize, peel extracts from all analyzed fruit showed comparable or better cosmetic-related properties than pulp extracts and might be considered multifunctional active ingredients of skin lightening, anti-aging, and protective cosmetics.

(2-Methylbutyryl)shikonin Naturally Occurring Shikonin Derivative Ameliorates the α-MSH-Induced Melanogenesis via ERK1/2 and p38 MAP Kinase-Mediated Down-Regulation of the MITF Transcription Factor

Cutaneous pigmentation is an important phenotypic trait whose regulation, despite recent advances, has yet to be completely elucidated. Melanogenesis, a physiological process of melanin production, is imperative for organism survival as it provides protection against the environmental insults that majorly involve sunlight-induced skin photodamage. However, immoderate melanin synthesis can cause pigmentation disorders associated with a psychosocial impact. In this study, the hypopigmentation effect of (2-methylbutyryl)shikonin, a natural product present in the root extract of Lithospermum erythrorhizon, and the underlying mechanisms responsible for the inhibition of melanin synthesis in α-MSH-stimulated B16F10 cells and C57BL/6J mice was studied. Non-cytotoxic concentrations of (2-methylbutyryl)shikonin significantly repressed cellular tyrosinase activity and melanin synthesis in both in vitro and in vivo models (C57BL/6J mice). (2-Methylbutyryl)shikonin remarkably abolished the protein expression of MITF, tyrosinase, tyrosinase-related protein 1, and tyrosinase-related protein 2, thereby blocking the production of pigment melanin via modulating the phosphorylation status of MAPK proteins, viz., ERK1/2 and p38. In addition, specific inhibition of ERK1/2 attenuated the inhibitory effects of (2-methylbutyryl)shikonin on melanin synthesis, whereas selective inhibition of p38 augmented the inhibitory effect of BSHK on melanin synthesis. Moreover, topical application of (2-methylbutyryl)shikonin on C57BL/6J mouse tails remarkably induced tail depigmentation. In conclusion, with these findings, we, for the first time, report the hypopigmentation effect of (2-methylbutyryl)shikonin via inhibition of cellular tyrosinase enzyme activity, subsequently ameliorating the melanin production, thereby indicating that (2-methylbutyryl)shikonin is a potential natural therapy for hyperpigmentation disorders.

Annurca Apple Oleolite as Functional Ingredient for the Formulation of Cosmetics with Skin-Antiaging Activity

The identification of natural remedies for the management of the skin aging process is an increasingly growing issue. In this context, ursolic acid (UA), a ubiquitous molecule, mainly contained in Annurca apple (AA) fruit, has demonstrated valuable cosmetic potential. To this end, in the current study, the AA oleolite (AAO, extract in sunflower oil containing 784.40 ± 7.579 µg/mL of UA) was evaluated to inhibit porcine elastase enzymatic reactions through a validated spectrophotometric method. AAO has shown a valuable capacity to contrast the elastase enzyme with a calculated IC50 of 212.76 mg/mL, in comparison to UA (IC50 of 135.24 μg/mL) pure molecules and quercetin (IC50 of 72.47 μg/mL) which are used as positive controls. In this context and in view of the valuable antioxidant potential of AAO, its topical formulation with 2.5% (w/w) AAO was tested in a placebo-controlled, double-blind, two-arm clinical study on 40 volunteers. Our results indicated that after 28 days of treatment, a significant reduction of the nasolabial fold (-7.2 vs. baseline T0, p < 0.001) and forehead wrinkles (-5.3 vs. baseline T0, p < 0.001) were registered in combination with a valuable improvement of the viscoelastic skin parameters, where skin pliability/firmness (R0) and gross elasticity (R2) were significantly ameliorated (-13% vs. baseline T0, p < 0.001 for R0 and +12% vs. baseline T0, p < 0.001 for R2). Finally, considering the positive correlation between skin elasticity and hydration, the skin moisture was evaluated through the estimation of Trans epidermal water loss (TEWL) and skin conductance.

In Vitro Safety and Efficacy Evaluation of a Juniperus communis Callus Culture Extract and Matricaria recutita Processing Waste Extract Combination as a Cosmetic Ingredient

For skin health promotion and cosmetic applications, combinations of plant cell extracts are extensively utilized. As most natural ingredient suppliers offer crude extracts from individual plants or specific isolated compounds, the potential interactions between them are assessed in the development phase of cosmetic products. The industry seeks extract combinations that have undergone optimization and scrutiny for their bioactivities. This study presents a combination of two sustainably produced botanical ingredients and outlines their chemical composition, in vitro safety, and bioactivity for skin health enhancement. The amalgamation comprises the extract of Matricaria recutita processing waste and the extract from Juniperus communis callus culture. Chemical analysis revealed distinct compounds within the extracts, and their combination led to a broader array of potentially synergistic compounds. In vitro assessments on skin cells demonstrated that the combination possesses robust antioxidant properties and the ability to stimulate keratinocyte proliferation, along with regulating collagen type I and matrix metalloproteinase 1 (MMP-1) production by dermal fibroblasts. The identified traits of this combination render it an appealing cosmetic component. To the best of our knowledge, this represents the first case when the extracts derived from medicinal plant processing waste and biotechnological plant cell cultivation processes have been combined and evaluated for their bioactivity.

A proof of concept: Clinical anti-aging efficacy and safety of Lactiplantibacillus plantarum LB244R® applied topically in a double-blinded placebo-controlled study

BACKGROUND

With the increasing age of the westernized population, there is also increasing economic and aesthetic interest in reducing the signs of skin aging. Additionally, the physical aspect of aging can be displeasing and have detrimental effects psychologically in individuals. Probiotics have shown potential as anti-aging agents, albeit proper studies are needed to confirm their potential.

AIMS

Proving that Lactiplantibacillus plantarum LB244R® could alleviate aging signs relative to its placebo vehicle.

PATIENTS/METHODS

In total, 46 subjects were randomly assigned either the ointment with live bacteria, L. plantarum LB244R® or its vehicle ointment, and had to use the assigned ointment twice daily for 56 days. On Day 0, Day 28, and Day 56 subepidermal low echogenic band (SLEB) thickness, dermal density, skin firmness and elasticity, skin hydration, transepidermal water loss (TEWL), skin pH, collagen fiber visualization using confocal microscopy, Crow's feet, spot score, skin smoothness, and complexion radiance were assessed by dermatologists.

RESULTS

All parameters except TEWL improved relative to their baseline (D0) for the active group. L. plantarum LB244R® improved SLEB thickness, dermal density, skin elasticity, skin hydration, and Crow's feet wrinkle score relative to the placebo vehicle ointment.

CONCLUSION

The study demonstrates an anti-aging effect of L. plantarum LB244R® for topical skin use in the first double-blinded, vehicle-ointment placebo-controlled clinical study.

Bitter Phytochemicals as Novel Candidates for Skin Disease Treatment

Skin diseases represent a global healthcare challenge due to their rising incidence and substantial socio-economic burden. While biological, immunological, and targeted therapies have brought a revolution in improving quality of life and survival rates for certain dermatological conditions, there remains a stringent demand for new remedies. Nature has long served as an inspiration for drug development. Recent studies have identified bitter taste receptors (TAS2Rs) in both skin cell lines and human skin. Additionally, bitter natural compounds have shown promising benefits in addressing skin aging, wound healing, inflammatory skin conditions, and even skin cancer. Thus, TAS2Rs may represent a promising target in all these processes. In this review, we summarize evidence supporting the presence of TAS2Rs in the skin and emphasize their potential as drug targets for addressing skin aging, wound healing, inflammatory skin conditions, and skin carcinogenesis. To our knowledge, this is a pioneering work in connecting information on TAS2Rs expression in skin and skin cells with the impact of bitter phytochemicals on various beneficial effects related to skin disorders.

Synergistic impact of arbutin and kaempferol-7-O-α-L-rhamnopyranoside from Nephelium lappaceum L. on whitening efficacy and stability of cosmetic formulations

Four flavonoid glycosides, namely quercetin-3-O-rhamnoside (1), kaempferol-3-O-β-D-glucopyranosyl (2), kaempferol-7-O-α-L-rhamnopyranoside (3), and kaempferol-3-O-β-D-glucopyranosyl-7-O-α-L-rhamnopyranoside (4), from Nephelium lappaceum L. seeds were evaluated for their efficacy against melanin inhibition in B16F10 melanoma cells and tyrosinase inhibition. Among them, kaempferol-7-O-α-L-rhamnopyranoside (3) displayed the highest potency in both activities without any significant cytotoxicity. The combination of compound 3 and arbutin in specific proportions demonstrated a synergistic effect (CI < 1) in inhibiting melanin production in B16F10 cells and tyrosinase inhibition. Additionally, a cosmetic formulation containing compound 3 and arbutin as active ingredients exhibited favorable stability under accelerated storage conditions. Quantitative analysis indicated that compound 3 and arbutin levels in the formulation were above 90% after one month of storage. Determination of the formulation's shelf life using the Q10 method, estimating it to be around 5.2 months from the date of manufacture. The synergy between arbutin and kaempferol-7-O-α-L-rhamnopyranoside (3) extracted from N. lappaceum substantially enhances both the whitening effectiveness and the stability of cosmetic formulations.

Plants with cosmetic uses

The use of plants as a source of active principles for cosmetics has significantly increased in the last few years. Safety, compatibility with all types of skin, fewer side effects, and availability are among the advantages of herbal cosmetics above synthetic ingredients. The present review aims to explore the most important plants used in cosmetics. A literature search was carried out in several electronic databases with the following phrases: skincare and plants; cosmetics and plants; natural and cosmetics; and natural and skincare. Furthermore, more detailed filters such as clinical studies, meta-analyses, and systemic reviews were applied to positive results. Various plants and plant extracts currently used in skin care, scaring, whitening, and aging, as well as in sun protection, acne, eczema, and others, have been included in this review. The effectiveness of these plants is based mainly on preclinical research, and to a lesser extent on clinical studies. Some plant extracts or oils have been tested clinically, such as onions, aloe, and tea tree oil, more than other plant extracts. Despite many studies on natural products to improve dermal needs, proper clinical cosmeceutical trials are much fewer than expected. Therefore, more clinical trials are needed to evaluate appropriate efficacy. Furthermore, new formulation technologies might enhance the cosmeceutical benefits, but more work is warranted.

A novel rice hull - microalgal biorefinery for the production of natural phenolic compounds comprising of rice hull acid pretreatment and a two-stage Botryococcus braunii cultivation process

Recently, the rising demand of the industry for natural phenolic antioxidant compounds has turned to the study of microalgae as potential sources. Yet, more economic substrates for microalgal cultivation are sought to lower production costs. To this end, the present work deals with the utilization of rice hull hydrolysate (RHH) as substrate for microalgae Botryococcus braunii through a novel two-stage cultivation system. Initially, RHH was optimized to maximize the contained nutrients while minimizing its inhibitors content. The optimum point was reached under 121 °C, 60 min, 2% (v/v) H2SO4, 30% (w/v) loading. Next, B. braunii was successfully grown first heterotrophically in RHH (25%, v/v), obtaining high biomass production (6.67 g L-1) and then autotrophically to enhance phenolics accumulation. At the end, a high phenolic content of 7.44 ± 0.60 mg Gallic Acid Equivalents g-1 DW was achieved from the produced biomass, thus highlighting the potential of this novel biotechnological method.

Effects of skin moisturization on various aspects of touch showing differences with age and skin site

The human body is encompassed by a thin layer of tissue, the skin, which is heterogenous and highly specialized to protect the body and encode interactions with the external world. There is a fundamental scientific drive to understand its function, coupled with the need to preserve skin as we age, which impacts on our physiological and psychological well-being. In the present study, we aimed to define differences in touch perception between age groups and with skin cream application. We investigated touch on the finger, the forearm and cheek in younger (20-28 years, n = 22) and older (65-75 years, n = 22) females. We measured skin hydration, touch detection, finger spatial discrimination, forearm tactile pleasantness together with electrodermal activity, and perceptual ratings about cream use, skin dryness, and cosmetic habits. Glabrous finger skin became drier and touch performance was impaired with age, but these aspects were preserved in hairy skin. Skin moisturization immediately increased hydration levels, but did not significantly change touch perception. We also found that touch appreciation increased with age. We conclude that reduced finger capacity may impact self-evaluation of the skin and that long-term skin care strategies should focus on hydrating the hand to preserve touch capacities.

Cyclodextrins for the Delivery of Bioactive Compounds from Natural Sources: Medicinal, Food and Cosmetics Applications

Cyclodextrins have gained significant and established attention as versatile carriers for the delivery of bioactive compounds derived from natural sources in various applications, including medicine, food and cosmetics. Their toroidal structure and hydrophobic cavity render them ideal candidates for encapsulating and solubilizing hydrophobic and poorly soluble compounds. Most medicinal, food and cosmetic ingredients share the challenges of hydrophobicity and degradation that can be effectively addressed by various cyclodextrin types. Though not new or novel-their first applications appeared in the market in the 1970s-their versatility has inspired numerous developments, either on the academic or industrial level. This review article provides an overview of the ever-growing applications of cyclodextrins in the delivery of bioactive compounds from natural sources and their potential application benefits.

Bioprospecting the Skin Microbiome: Advances in Therapeutics and Personal Care Products

Bioprospecting is the discovery and exploration of biological diversity found within organisms, genetic elements or produced compounds with prospective commercial or therapeutic applications. The human skin is an ecological niche which harbours a rich and compositional diversity microbiome stemming from the multifactorial interactions between the host and microbiota facilitated by exploitable effector compounds. Advances in the understanding of microbial colonisation mechanisms alongside species and strain interactions have revealed a novel chemical and biological understanding which displays applicative potential. Studies elucidating the organismal interfaces and concomitant understanding of the central processes of skin biology have begun to unravel a potential wealth of molecules which can exploited for their proposed functions. A variety of skin-microbiome-derived compounds display prospective therapeutic applications, ranging from antioncogenic agents relevant in skin cancer therapy to treatment strategies for antimicrobial-resistant bacterial and fungal infections. Considerable opportunities have emerged for the translation to personal care products, such as topical agents to mitigate various skin conditions such as acne and eczema. Adjacent compound developments have focused on cosmetic applications such as reducing skin ageing and its associated changes to skin properties and the microbiome. The skin microbiome contains a wealth of prospective compounds with therapeutic and commercial applications; however, considerable work is required for the translation of in vitro findings to relevant in vivo models to ensure translatability.

The Most Potent Natural Pharmaceuticals, Cosmetics, and Food Ingredients Isolated from Plants with Deep Eutectic Solvents

There is growing interest in reducing the number of synthetic products or additives and replacing them with natural ones. The pharmaceutical, cosmetic, and food industries are especially focused on natural and bioactive chemicals isolated from plants or microorganisms. The main challenge here is to develop efficient and ecological methods for their isolation. According to the strategies and rules of sustainable development and green chemistry, green solvents and environmentally friendly technologies must be used. The application of deep eutectic solvents as efficient and biodegradable solvents seems to be a promising alternative to traditional methods. They are classified as being green and ecological but, most importantly, very efficient extraction media compared to organic solvents. The aim of this review is to present the recent findings on green extraction, as well as the biological activities and the possible applications of natural plant ingredients, namely, phenolics, flavonoids, terpenes, saponins, and some others. This paper thoroughly reviews modern, ecological, and efficient extraction methods with the use of deep eutectic solvents (DESs). The newest findings, as well as the factors influencing the efficiency of extraction, such as water content, and hydrogen bond donor and acceptor types, as well as the extraction systems, are also discussed. New solutions to the major problem of separating DESs from the extract and for solvent recycling are also presented.

Anti-Melanogenic Effects of Fractioned Cynanchum atratum by Regulation of cAMP/MITF Pathway in a UVB-Stimulated Mice Model

Based on traditional pharmacological applications and partial in vitro data, Cynanchum atratum (CA) is proposed to act on skin whitening. However, its functional evaluation and underlying mechanisms have yet to be identified. This study aimed to examine the anti-melanogenesis activity of CA fraction B (CAFB) on UVB-induced skin hyperpigmentation. Forty C57BL/6j mice were exposed to UVB (100 mJ/cm², five times/week) for eight weeks. After irradiation, CAFB was applied to the left ear once a day for 8 weeks (the right ear served as an internal control). The results showed that CAFB significantly reduced melanin production in the ear skin, as indicated by the gray value and Mexameter melanin index. In addition, CAFB treatment notably decreased melanin production in α-MSH-stimulated B16F10 melanocytes, along with a significant reduction in tyrosinase activity. Cellular cAMP (cyclic adenosine monophosphate), MITF (microphthalmia-associated transcription factor), and tyrosinase-related protein 1 (TRP1) were also noticeably downregulated by CAFB. In conclusion, CAFB is a promising ingredient for treating skin disorders caused by the overproduction of melanin and its underlying mechanisms involving the modulation of tyrosinase, mainly mediated by the regulation of the cAMP cascade and MITF pathway.

Targeting Tyrosinase in Hyperpigmentation: Current Status, Limitations and Future Promises

Hyperpigmentation is a common and distressing dermatologic condition. Since tyrosinase (TYR) plays an essential role in melanogenesis, its inhibition is considered a logical approach along with other therapeutic methods to prevent the accumulation of melanin in the skin. Thus, TYR inhibitors are a tempting target as the medicinal and cosmetic active agents of hyperpigmentation disorder. Among TYR inhibitors, hydroquinone is a traditional lightening agent that is commonly used in clinical practice. However, despite good efficacy, prolonged use of hydroquinone is associated with side effects. To overcome these shortcomings, new approaches in targeting TYR and treating hyperpigmentation are desperately requiredessentialneeded. In line with this purpose, several non-hydroquinone lightening agents have been developed and suggested as hydroquinone alternatives. In addition to traditional approaches, nanomedicine and nanotheranostic platforms have been recently proposed in the treatment of hyperpigmentation. In this review, we discuss the available strategies for the management of hyperpigmentation with a focus on TYR inhibition. In addition, alternative treatment options to hydroquinone are discussed. Finally, we present nano-based strategies to improve the therapeutic effect of drugs prescribed to patients with skin disorders.

How to Promote Skin Repair? In-Depth Look at Pharmaceutical and Cosmetic Strategies

Skin repair encompasses epidermal barrier repair and wound healing which involves multiple cellular and molecular stages. Therefore, many skin repair strategies have been proposed. In order to characterize the usage frequency of skin repair ingredients in cosmetics, medicines, and medical devices, commercialized in Portuguese pharmacies and parapharmacies, a comprehensive analysis of the products' composition was performed. A total of 120 cosmetic products, collected from national pharmacies online platforms, 21 topical medicines, and 46 medical devices, collected from INFARMED database, were included in the study, revealing the top 10 most used skin repair ingredients in these categories. A critical review regarding the effectiveness of the top ingredients was performed and an in-depth analysis focused on the top three skin repair ingredients pursued. Results demonstrated that top three most used cosmetic ingredients were metal salts and oxides (78.3%), vitamin E and its derivatives (54.2%), and Centella asiatica (L.) Urb. extract and actives (35.8%). Regarding medicines, metal salts and oxides were also the most used (47.4%) followed by vitamin B5 and derivatives (23.8%), and vitamin A and derivatives (26.3%). Silicones and derivatives were the most common skin repair ingredients in medical devices (33%), followed by petrolatum and derivatives (22%) and alginate (15%). This work provides an overview of the most used skin repair ingredients, highlighting their different mechanisms of action, aiming to provide an up-to-date tool to support health professionals' decisions.

Evaluating the Application Potential of a Recombinant Ganoderma Protein as Bioactive Ingredients in Cosmetics

The aim of this study was to evaluate the application potential of a recombinant fungal immunomodulatory protein from Ganoderma lucidum (rFIP-glu). First, a recombinant plasmid pPIC9K::FIP-glu-His was transferred into Pichia pastoris for the production of protein. The protein was then to assess its free radical scavenging abilities and the effect on the viability of both human immortalized keratinocytes (HaCaT cells) and mouse B16-F10 melanoma cells (B16 cells) in vitro, followed by the effect on the melanin synthesis of B16 cells. The results of SDS-PAGE and western blot showed that rFIP-glu was successfully expressed. Furtherly, a bioactivity assay in vitro indicated that the scavenging rate of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals reached 84.5% at 6.0 mg/mL (p ≤ 0.0001) of rFIP-glu, showing strong antioxidant activity. Subsequently, a safety evaluation demonstrated that rFIP-glu promoted the proliferation of HaCaT cells, with the cell viability reaching 124.3% at 48 μg/mL (p ≤ 0.01), regarding the cell viability of B16 cells after exposure to rFIP-glu (48 μg/mL) significantly inhibited, to 80.7% (p ≤ 0.01). Besides, rFIP-glu inhibited the melanin synthesis of B16 cells in a dose-dependent manner from 100–1000 μg/mL, and rFIP-glu at 500 μg/mL (p ≤ 0.01) exhibited the highest intracellular melanin amount reduction of 16.8%. Furthermore, a mechanism analysis showed that rFIP-glu inhibited tyrosinase (TYR) activity by up-regulating the expression of the microphthalmia-associated transcription factor (MITF) and down-regulating the gene expression of TYR and tyrosinase-related protein-1 (TYRP-1), thus inhibiting melanin synthesis. The data implied that rFIP-glu had significant antioxidant activity and whitening potency. It should be used as raw materials for cosmeceutical applications.

Marine Natural Products as Innovative Cosmetic Ingredients

Over the course of the last 20 years, numerous studies have identified the benefits of an array of marine natural ingredients for cosmetic purposes, as they present unique characteristics not found in terrestrial organisms. Consequently, several marine-based ingredients and bioactive compounds are under development, used or considered for skin care and cosmetics. Despite the multitude of cosmetics based on marine sources, only a small proportion of their full potential has been exploited. Many cosmetic industries have turned their attention to the sea to obtain innovative marine-derived compounds for cosmetics, but further research is needed to determine and elucidate the benefits. This review gathers information on the main biological targets for cosmetic ingredients, different classes of marine natural products of interest for cosmetic applications, and the organisms from which such products can be sourced. Although organisms from different phyla present different and varied bioactivities, the algae phylum seems to be the most promising for cosmetic applications, presenting compounds of many classes. In fact, some of these compounds present higher bioactivities than their commercialized counterparts, demonstrating the potential presented by marine-derived compounds for cosmetic applications (i.e., Mycosporine-like amino acids and terpenoids’ antioxidant activity). This review also summarizes the major challenges and opportunities faced by marine-derived cosmetic ingredients to successfully reach the market. As a future perspective, we consider that fruitful cooperation among academics and cosmetic industries could lead to a more sustainable market through responsible sourcing of ingredients, implementing ecological manufacturing processes, and experimenting with inventive recycling and reuse programs.