Methods for evaluation of cosmetic antioxidant capacity

Valorisation of Raspberry Seeds in Cosmetic Industry-Green Solutions

The fruit processing industry generates large quantities of by-products well known to be rich in bioactive compounds with numerous nutritional properties and beneficial effects for human health. We developed a strategy to valorise raspberry seeds and obtain valuable ingredients with potential application in cosmetic skincare formulas. Cold press extraction technology was applied to extract oil, and the remaining defatted raspberry seed cake was treated with three proline based deep eutectic solvents (DES) to extract polyphenols. The most potent was proline/citric acid extract, with free and total ellagic acid content (52.4 mg/L and 86.4 mg/L), total phenolic content (TPC, 550.1 mg GAE/L) and radical scavenging activity (RSA, 4742.7 mmol TE/L). After the direct mixing of the extract and after encapsulation with starch as a carrier, the skincare emulsion and microemulsion were characterised by irritation potential (Zein test), transepidermal water loss (TEWL), red blood cell (RBC), and DPPH antioxidant test. The resulting preparations were of improved quality in comparison to the control hand cream, with a low skin irritation effect, lower TEWL, and higher antioxidant potential. This work complies with circular economy principles and green technology standards, and represents the efficient model on how to reuse natural resources through waste minimization.

A guide to the use of bioassays in exploration of natural resources

Bioassays are the main tool to decipher bioactivities from natural resources thus their selection and quality are critical for optimal bioprospecting. They are used both in the early stages of compounds isolation/purification/identification, and in later stages to evaluate their safety and efficacy. In this review, we provide a comprehensive overview of the most common bioassays used in the discovery and development of new bioactive compounds with a focus on marine bioresources. We present a comprehensive list of practical considerations for selecting appropriate bioassays and discuss in detail the bioassays typically used to explore antimicrobial, antibiofilm, cytotoxic, antiviral, antioxidant, and anti-ageing potential. The concept of quality control and bioassay validation are introduced, followed by safety considerations, which are critical to advancing bioactive compounds to a higher stage of development. We conclude by providing an application-oriented view focused on the development of pharmaceuticals, food supplements, and cosmetics, the industrial pipelines where currently known marine natural products hold most potential. We highlight the importance of gaining reliable bioassay results, as these serve as a starting point for application-based development and further testing, as well as for consideration by regulatory authorities.

Decoding Cosmetic Complexities: A Comprehensive Guide to Matrix Composition and Pretreatment Technology

Despite advancements in analytical technologies, the complex nature of cosmetic matrices, coupled with the presence of diverse and trace unauthorized additives, hinders the application of these technologies in cosmetics analysis. This not only impedes effective regulation of cosmetics but also leads to the continual infiltration of illegal products into the market, posing serious health risks to consumers. The establishment of cosmetic regulations is often based on extensive scientific experiments, resulting in a certain degree of latency. Therefore, timely advancement in laboratory research is crucial to ensure the timely update and adaptability of regulations. A comprehensive understanding of the composition of cosmetic matrices and their pretreatment technologies is vital for enhancing the efficiency and accuracy of cosmetic detection. Drawing upon the China National Medical Products Administration's 2021 Cosmetic Classification Rules and Classification Catalogue, we streamline the wide array of cosmetics into four principal categories based on the following compositions: emulsified, liquid, powdered, and wax-based cosmetics. In this review, the characteristics, compositional elements, and physicochemical properties inherent to each category, as well as an extensive overview of the evolution of pretreatment methods for different categories, will be explored. Our objective is to provide a clear and comprehensive guide, equipping researchers with profound insights into the core compositions and pretreatment methods of cosmetics, which will in turn advance cosmetic analysis and improve detection and regulatory approaches in the industry.

Antioxidant and Anti-Inflammatory Activities of Sargassum macrocarpum Extracts

Oxidative stress and the inflammatory response are known to be the most important pathological factors for aging skin cells. Therefore, substances that protect skin cells from oxidative stress and inflammatory reactions of the skin have potential as functional ingredients for skin care. In the present study, we investigated the potential of Sargassum macrocarpum as an anti-inflammatory candidate for inflammatory skin disease. Antioxidant and anti-inflammatory activities are desirable properties in such functional materials. The total polyphenol content as well as antioxidant and anti-inflammatory activities were evaluated in hot-water (HES) and ethanol (EES) extracts of S. macrocarpum. The polyphenol content was higher in the HES (HES: 115.9 ± 15.3 mg GA/g, EES: 3.9 ± 0.5 mg GA/g), and the HES also had ABTS (HES: IC₅₀ 1.0 ± 0.0 mg/mL, EES: IC₅₀ 16.09 ± 0.7 mg/mL) and DPPH (HES: IC₅₀ 6.50 ± 0.3 mg/mL, EES: IC₅₀ 35.3 ± 3.1 mg/mL) radical scavenging capacities as well as FRAP activity (HES: IC₅₀ 18.8 ± 0.4 mg/mL, EES: IC₅₀ n.d.). Compared with the EES at the equivalent concentration range (1.25-20 μg/mL), the HES exerted a more potent inhibitory activity on LPS-stimulated nitric oxide (10.3-43.1%), IL-6 (15.7-45.0%), and TNF-α (14.1-20.8%) in RAW 264.7 macrophage cells in addition to TNF-α and IFN-γ-facilitated IL-6 (10.9-84.1%) and IL-8 (7.7-73.2%) in HaCaT keratinocytes. These results suggested that water-soluble materials might be deeply involved in the antioxidant and anti-inflammatory activity in S. macrocarpum. General composition analysis indicated that the HES contains more carbohydrates and polyphenols than the EES, and the monosaccharide composition analysis suggested that fucose-containing sulfated polysaccharide and β-glucan might be potent anti-inflammatory candidates in the HES. The present study presents important preliminary results and a valuable strategy for developing novel anti-skin dermatitis candidates using a hot-water extract of S. macrocarpum.

Fast Inverted Photoprotective o/w Emulsions Loaded With Dihydroquercetin and β-Carotene: An Innovative Approach to In Vitro Assessment of Antioxidant Activity in a Bioenvironment

Fast inverted, oil-in-water (o/w) emulsions, also known as SWitch-Oil-Phase (SWOP) emulsions, express the performances of both o/w and water-in-oil (w/o) emulsions during application to the skin, favoring their use as cosmetic carriers in sunscreen products. The objective of this study was to investigate the antioxidant potential (by 2 different methods) and the ultraviolet (UV) absorption ability of SWOP emulsion (S) with incorporated plant-based antioxidants dihydroquercetin (DHQ) and β-carotene (βC), using quercetin (Q) in a reference emulsion, in addition to the evaluation of their physicochemical properties and stability. A new biochemical extracellular model for in vitro assessment of antioxidative properties for the SWOP emulsions (S, SQ, SDHQ, and SDHQβC) was developed and compared with the results of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. The analyses were performed at 20 °C and 37 °C, and oxidative stress parameters were monitored and statistically analyzed. The sun protection factor (SPF) of the samples was determined in vitro. Q and DHQ incorporated into the SWOP emulsion exhibited a strong DPPH radical scavenging ability. Neither incorporated nor pure βC showed DPPH radical scavenging ability at the tested concentrations. Contrary to that, in the bioenvironment conditions, SDHQβC showed minor antioxidative effects increase and also a significant decrease in exogenous pro-oxidative effects, caused by pro-oxidant, when compared to SDHQ. The obtained SPFs of SDHQβC, SDHQ, and SQ were 5.19, 4.65, and 3.35, respectively. The physicochemical stability of the emulsions was satisfactory during 1 month storage. The presented results demonstrated that the SWOP emulsion is a suitable carrier for antioxidants with a photoprotective ability. The novel biochemical approach could be used in addition to DPPH assay with several advantages, relevant for the testing of antioxidant activity of potential active ingredients in cosmetic products.

The beauty of biocatalysis: sustainable synthesis of ingredients in cosmetics

Covering: 2015 up to July 2021The market for cosmetics is consumer driven and the desire for green, sustainable and natural ingredients is increasing. The use of isolated enzymes and whole-cell organisms to synthesise these products is congruent with these values, especially when combined with the use of renewable, recyclable or waste feedstocks. The literature of biocatalysis for the synthesis of ingredients in cosmetics in the past five years is herein reviewed.

The New Challenge of Green Cosmetics: Natural Food Ingredients for Cosmetic Formulations

Nowadays, much attention is paid to issues such as ecology and sustainability. Many consumers choose “green cosmetics”, which are environmentally friendly creams, makeup, and beauty products, hoping that they are not harmful to health and reduce pollution. Moreover, the repeated mini-lock downs during the COVID-19 pandemic have fueled the awareness that body beauty is linked to well-being, both external and internal. As a result, consumer preferences for makeup have declined, while those for skincare products have increased. Nutricosmetics, which combines the benefits derived from food supplementation with the advantages of cosmetic treatments to improve the beauty of our body, respond to the new market demands. Food chemistry and cosmetic chemistry come together to promote both inside and outside well-being. A nutricosmetic optimizes the intake of nutritional microelements to meet the needs of the skin and skin appendages, improving their conditions and delaying aging, thus helping to protect the skin from the aging action of environmental factors. Numerous studies in the literature show a significant correlation between the adequate intake of these supplements, improved skin quality (both aesthetic and histological), and the acceleration of wound-healing. This review revised the main foods and bioactive molecules used in nutricosmetic formulations, their cosmetic effects, and the analytical techniques that allow the dosage of the active ingredients in the food.

Fungal melanin as a biocompatible broad-spectrum sunscreen with high antioxidant activity

Melanin is considered a bio-inspired dermo-cosmetic component due to its high UV absorption and antioxidant activity. Among various melanin sources, fungal melanin is a promising candidate for sunscreen because of its sustainability and scalability; however, quantitative assessment of its function has not yet been sufficiently explored. In this study, melanin samples derived from Amorphotheca resinae were prepared, followed by the evaluation of their sunscreen performance, antioxidant activity, and cytotoxicity. Melanin-blended cream was prepared by blending a melanin suspension and a pure cream. The cream showed an in vitro sun protection factor value of 2.5 when the pigment content was 5%. The cream showed a critical wavelength of approximately 388 nm and a UVA/UVB ratio of more than 0.81, satisfying the broad-spectrum sunscreen requirement. Oxygen radical absorbance capacity assays indicated that fungal melanin had antioxidant activity similar to ascorbic acid but higher than reduced glutathione. Fungal melanin had no statistically significant cytotoxicity to human keratinocyte cell lines until 72 h of exposure, even at a concentration of 4 mg mL-1. Consequently, melanin pigment can be used as a biocompatible broad-spectrum sunscreen with high antioxidant activity and as a practical alternative in dermo-cosmetic formulations.

Role of Molecular Hydrogen in Skin Diseases and its Impact in Beauty

In today's society, healthy skin and a beautiful appearance are considered the foundation of general well-being. The skin is the largest organ of the body and plays an important role in protecting it against various hazards such as environmental, physical, chemical, and biological hazards. These factors include mediators that lead to oxidation reactions that produce reactive oxygen/nitrogen species and additional oxidants in the skin cells. An increase in oxidants beyond the antioxidant capacity of its defense system causes oxidative stress and chronic inflammation in the body. This response can cause further disruption of collagen fibers and hinder the functioning of skin cells that may result in the development of various skin diseases including psoriasis, atopic dermatitis, and aging. In this review, we summarized the present information related to the role of oxidative stress in the pathogenesis of dermatological disorders, and its impact on physical beauty and the daily lives of patients. We also discussed how molecular hydrogen exhibits a therapeutic effect against skin diseases via its effects on oxidative stress. Furthermore, findings from this summary review indicate that molecular hydrogen might be an effective treatment modality for the prevention and treatment of skin-related illnesses.

Preparation and Evaluation Pumpkin Seed Oil-based Vitamin E Cream Formulations for Topical Application

Plant seed oil is often incorporated into the cream emulsions to provide multifunctional effects on the skin. In the current study, pumpkin seed oil (PSO) was used to develop a stable oil-in-water emulsion. The study aimed to optimise PSO cream formulation and determine the synergistic effect of the PSO with vitamin E oil added. The physical properties, antioxidant activities and storage stability of the formulations were analysed. Besides, the synergistic effect of the best formulation was analysed based on α-tocopherol content using ultra-high performance liquid chromatography (UHPLC). The storage stability test was assessed upon storing at 25 ± 2°C and 40 ± 2°C for 12 weeks. The best formulation (20% PSO, vitamin E oil and beeswax) selected showed physically and microbiologically stable. The incorporation of vitamin E oil into the formulation produced with PSO was found to be compatible, as it showed a synergistic effect in the amount of α-tocopherol content (combination index (CI) = 0.98). Thus, PSO had shown its potency to be incorporated into the topical products with a promising potential in delivering additional properties that can nourish the skin.

Naphtho-Gamma-Pyrones Produced by Aspergillus tubingensis G131: New Source of Natural Nontoxic Antioxidants

Seven naphtho-gamma-pyrones (NγPs), including asperpyrone E, aurasperone A, dianhydroaurasperone C, fonsecin, fonsecinone A, fonsecin B, and ustilaginoidin A, were isolated from Aspergillus tubingensis G131, a non-toxigenic strain. The radical scavenging activity of these NγPs was evaluated using ABTS assay. The Trolox equivalent antioxidant capacity on the seven isolated NγPs ranged from 2.4 to 14.6 μmol L^-1. The toxicity and ability of the NγPs to prevent H₂O₂-mediated cell death were evaluated using normal/not cancerous cells (CHO cells). This cell-based assay showed that NγPs: (1) Are not toxic or weakly toxic towards cells and (2) are able to protect cells from oxidant injuries with an IC₅₀ on H₂O₂-mediated cell death ranging from 2.25 to 1800 μmol mL^-1. Our data show that A. tubingensis G131 strain is able to produce various NγPs possessing strong antioxidant activities and low toxicities, making this strain a good candidate for antioxidant applications in food and cosmetic industries.

In situ antioxidant activity of a dermo-cosmetic product: A randomized controlled clinical study

Ultraviolet light enhances the generation of reactive oxygen species that are responsible for skin photoageing. The aim of this randomized, vehicle- and active-controlled double-blind, intra-individual monocentric study was to evaluate in situ the antioxidant activity of a dermo-cosmetic product in photoaged skin. Twenty healthy volunteers had defined skin areas randomized to receive a topical product containing 3 antioxidants (pre-tocopheryl® , retinaldehyde and glycylglycine ole-amide), its vehicle and a positive antioxidant control cream. The products were applied daily for 30-day period. The skin areas were exposed to a controlled dose of UVA rays, and the skin oxidative status was evaluated 4 and 24 hours post-UVA exposure at D0 (basal value) and after 15 and 30 days of product application. Skin layers were collected by stripping, and antioxidant capacity was measured using the ferric reducing ability of a plasma assay. Lipid peroxidation (LPO) was assessed using the malonyldialdehyde test. The tested product significantly improved the skin antioxidant capacity after 15 and 30 days and significantly decreased the basal level of the skin LPO. The skin LPO level significantly decreased 4 and 24 hours after UVA exposure at 15 and 30 days. These findings were comparable to positive control treated sites and were significantly different from the vehicle and untreated sites. This minimally invasive methodology enabled a quantitative evaluation of potent antioxidant activity in situ in the stratum corneum reflecting real-life skin conditions and confirming the benefits of the topical application of a product containing 3 antioxidants in the prevention of UVA-induced oxidative damage.

Polyphenols as natural antioxidants in cosmetics applications

BACKGROUND

Currently, there is a great interest in cosmetics prepared on natural resources bases and this may restrict the use of synthetic substances. Plants play a relevant role as a source of biologically active natural products with cosmetic and dermatological importance. According to this context, polyphenolic extracts are highlighted because they have proven antioxidant, anti-inflammatory, anti-aging, antimicrobial, and supporting activity in solar photoprotection.

AIMS

The purpose this study were reviewed at reporting the antioxidant activity of phenolic compounds, mainly applied to dermatological therapy, and highlighting the action mechanisms and structure-activity relationship.

METHODOLOGY

In September 2017, we performed a literature search in PubMed and Scielo for scientific researches, antioxidant studies, and systemic reviews. The search terms we used were "PHYTOCOSMETICS" AND "ANTIOXIDANT ACTIVITY" OR "PHENOLIC COMPOUNDS" (from 2000). As inclusion criteria were used relevant original articles, scientific research in the area of interest, and crucial reference articles. Exclusion criteria were: duplicate publications, non-relevant articles and not published in English.

RESULTS

The potential cosmetic application of phenolic compounds as natural antioxidants has been attributed to the chemical structure of these compounds, which to interfere in different phases of the oxidation mechanism.

CONCLUSION

The use of phenolic extracts emerges as a viable alternative for cosmetic application, ensuring a commitment to sustainability. However, it is of crucial importance to evaluate the toxicity risks of raw materials and finished products.

Topical monomethylsilanetriol can deliver silicon to the viable skin

OBJECTIVE

Organic silicon has been linked to positive effects on the skin rejuvenation, mainly by the oral route. Thus, the main objective of the present study was to assess whether monomethylsilanetriol (MMST, a source of organic silicon) can deliver silicon to the epidermis and dermis, when applied topically in a cream. Once the hypothesis was confirmed, the present study also evaluated whether the product was toxic to keratinocytes; additionally, its possible antioxidant activity was assessed.

METHODS

The ex vivo skin permeation profile was determined using human skin in Franz-cells equipment; cytotoxicity was assessed using HaCaT keratinocytes. Antioxidant capacity was determined as scavenging activity, measured according to the 1,1-diphenyl-2-picrylhydrazil free radical method.

RESULTS

The permeation percentage was almost 60% of the applied MMST, with a large quantity of drug found in the viable epidermis and dermis. The cell viability assay showed no significant difference in the percentage of viable keratinocytes among the treated groups at the doses used. In terms of antioxidant activity, the IC₅₀ value obtained was 2400 μg mL^-1 . Low antioxidant activity, negligible toxicity for keratinocytes and a significant percentage of permeation were observed.

CONCLUSION

We provide evidence that MMST applied topically can deliver silicon to the skin in biorelevant levels for cosmetic purposes.

A DFT mechanistic and kinetic study on the reaction of phloroglucinol with •OH in different media: Hydrogen atom transfer versus oxidation

A theoretical study on the reaction of phloroglucinol with •OH has been performed with the aim of elucidating the geometric, energetic and kinetic properties of the reaction as well as identifying the preferred reaction pathway. Three reaction mechanisms have been considered, namely, direct hydrogen atom abstraction, addition–elimination mechanism in the absence and in the presence of a base catalyst and oxidation mechanism in the absence and in the presence of O2. The study has been performed using the DFT/M06[Formula: see text]2X, DFT/BHHLYP and DFT/MPW1K methods in conjunction with either the 6-31++G(d,p) or the 6-311++G(3df,2p) basis set. The energetic parameters are influenced by the type of function utilized and the media in which the calculation is done. The direct hydrogen abstraction mechanism provides the smallest branching ratio with respect to the •OH addition mechanisms. The PG + •OH reaction under atmospheric conditions saturated with O2 would predominantly form tetrahydroxybenzene; the predominant product within the biological system would largely depend on physiological conditions; under pH [Formula: see text] 7 and with oxygen dissolved within the biological system, the preferred product would be tetrahydroxybenzene; however, if the reaction takes place in some part of the biological system where the pH [Formula: see text] 7, the preferred product would be the phenoxyl radical.

Selective Synthesis of 3-O-Palmitoyl-Silybin, a New-to-Nature Flavonolignan with Increased Protective Action against Oxidative Damages in Lipophilic Media

A selective acylation protocol using cerium chloride (CeCl₃) as catalyst was applied to functionalize silybinin (1), a natural antioxidant flavonolignan from milk thistle fruit, in order to increase its solubility in lipophilic media while retaining its strong antioxidant activity. The selective esterification of 1 at the position 3-OH with a palmitate acyl chain leading to the formation of the 3-O-palmitoyl-silybin (2) was confirmed by both mass spectroscopy (MS) and nuclear magnetic resonance (NMR) analyses. The antioxidant activity of 1 was at least retained and even increased with the CUPRAC assay designed to estimate the antioxidant activity of both hydrophilic and lipophilic compounds. Finally, the 3-O-palmitoylation of 1, resulting in the formation of 2, also increased its anti-lipoperoxidant activity (i.e., inhibition of conjugated diene production) in two different lipophilic media (bulk oil and o/w emulsion) subjected to accelerated storage test.

Single Laboratory Validation of a Quantitative Core Shell-Based LC Separation for the Evaluation of Silymarin Variability and Associated Antioxidant Activity of Pakistani Ecotypes of Milk Thistle (Silybum Marianum L.)

Fruits of Silybum marianum (L.) Gaernt are the main source of taxifolin derived flavonolignans. Together, these molecules constitute a mixture called silymarin with many useful applications for cosmetic and pharmaceutic industries. Here, a validated method for the separation of the silymarin constituents has been developed to ensure precision and accuracy in their quantification. Each compound was separated with a high reproducibility. Precision and repeatability of the quantification method were validated according to the AOAC recommendations. The method was then applied to study the natural variability of wild accessions of S. marianum. Analysis of the variation in the fruits composition of these 12 accessions from Pakistan evidenced a huge natural diversity. Correlation analysis suggested a synergistic action of the different flavonolignans to reach the maximal antioxidant activity, as determined by cupric ion reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) assays. Principal component analysis (PCA) separated the 12 accessions into three distinct groups that were differing from their silymarin contents, whereas hierarchical clustering analysis (HCA) evidenced strong variations in their silymarin composition, leading to the identification of new silybin-rich chemotypes. These results proved that the present method allows for an efficient separation and quantification of the main flavonolignans with potent antioxidant activities.

Encapsulation of Olive Leaves Extracts in Biodegradable PLA Nanoparticles for Use in Cosmetic Formulation

The aim of the current work was to encapsulate olive leaves extract in biodegradable poly(lactic acid) nanoparticles, characterize the nanoparticles and define the experimental parameters that affect the encapsulation procedure. Moreover, the loaded nanoparticles were incorporated in a cosmetic formulation and the stability of the formulation was studied for a three-month period of study. Poly(lactic acid) nanoparticles were prepared by the nanoprecipitation method. Characterization of the nanoparticles was performed using a variety of techniques: size, polydispersity index and ζ-potential were measured by Dynamic Light Scattering; morphology was studied using Scanning Electron Microscopy; thermal properties were investigated using Differential Scanning Calorimetry; whereas FT-IR spectroscopy provided a better insight on the encapsulation of the extract. Encapsulation Efficiency was determined indirectly, using UV-Vis spectroscopy. The loaded nanoparticles exhibited anionic ζ-potential, a mean particle size of 246.3 ± 5.3 nm (Pdi: 0.21 ± 0.01) and equal to 49.2%, while olive leaves extract release from the nanoparticles was found to present a burst effect at the first 2 hours. Furthermore, the stability studies of the loaded nanoparticles’ cosmetic formulation showed increased stability compared to the pure extract, in respect to viscosity, pH, organoleptic characteristics, emulsions phases and grid.

In vivo and ex vivo evaluation of cosmetic properties of seedcakes

The seedcakes are a potential source of natural bioactive substances: antioxidants, protein, and carbohydrates. Thus, they may scavenge free radicals and have an effect on the stratum corneum hydration and epidermal barrier function. The aim of the study was to evaluate the in vivo and ex vivo properties of emulsions with the seedcake extracts using the pH meter, corneometer, tewameter, methyl nicotinate model of micro-inflammation in human skin, and tape stripping of the stratum corneum. The in vivo and ex vivo studies showed that the emulsions with Oenothera biennis, Borago officinalis, and Nigella sativa seedcake extracts have anti-inflammatory and antioxidant activity. The 6-week topical application of the emulsions with the B. officinalis and N. sativa seedcakes significantly reduced skin irritation and influenced the improvement of the skin hydration and epidermal barrier function compared with placebo. The seedcakes due to their antioxidant and anti-inflammatory activities have potential application in anti-aging, moisturizing, mitigating, and protective cosmetics.

A natural broad-spectrum sunscreen formulated from the dried extract of Brazilian Lippia sericea as a single UV filter

The photoprotective activity of someLippiaspecies is described for the first time, in terms of UVA and UVB protection.

Skin and antioxidants

It is estimated that total sun exposure occurs non-intentionally in three quarters of our lifetimes. Our skin is exposed to majority of UV radiation during outdoor activities, e.g. walking, practicing sports, running, hiking, etc. and not when we are intentionally exposed to the sun on the beach. We rarely use sunscreens during those activities, or at least not as much and as regular as we should and are commonly prone to acute and chronic sun damage of the skin. The only protection of our skin is endogenous (synthesis of melanin and enzymatic antioxidants) and exogenous (antioxidants, which we consume from the food, like vitamins A, C, E, etc.). UV-induced photoaging of the skin becomes clinically evident with age, when endogenous antioxidative mechanisms and repair processes are not effective any more and actinic damage to the skin prevails. At this point it would be reasonable to ingest additional antioxidants and/or to apply them on the skin in topical preparations. We review endogenous and exogenous skin protection with antioxidants.