Grape pomace retains polyphenols in the peels and in the seeds after winemaking, which is indicative of the high valorization potential of this industrial waste. There is strong evidence that phenolics are robust antioxidants and confer photoprotection; thus, it is rational to apply these active compounds from winemaking waste to sunscreens, in order to increase UV protection. Despite the importance of this class of cosmetics to public health, more efficacious strategies are still needed to overcome the problems caused by the photoinstability of some UV filters. The hydroethanolic extract of Vitis vinifera L. grapes was obtained by percolation and then lyophilized. Six formulations were developed: Type I—cosmetic base and UV filters; Type II—cosmetic base and extract; and Type III—cosmetic base, extract and UV filters. Each formulation was prepared in the pHs 5 and 7. The antioxidant activities of the samples were measured by DPPH• and expressed in Trolox® equivalents (TE), and their photostability and in vitro sun protection factor (SPF) were analyzed by diffuse reflectance spectrophotometry. The anti-radical efficiencies observed in the formulations with grape extract were: (II) 590.12 ± 0.01 μmol TE g−1 at pH 5 and 424.51 ± 0.32 μmol TE g−1 at pH 7; (III) 550.88 ± 0.00 μmol TE g−1 at pH 5 and 429.66 ± 0.10 μmol TE g−1, at pH 7, demonstrating that the UV filters, butylmethoxydibenzoyl methane, ethylhexyl methoxycinnamate and ethylhexyl dimethyl 4-aminobenzoic acid had no influence on this effect. The photoprotective efficacy and the photostability of formulation III containing the extract and UV filters at pH 5 suggested that a synergism between the active molecules provided an 81% increase in SPF. Additionally, this was the only sample that maintained a broad spectrum of protection after irradiation. These results confirmed that the grape pomace extract has multifunctional potential for cosmetic use, mainly in sunscreens, granting them superior performance.

In winemaking, a large amount of grape pomace is produced that is rich in polyphenolics and highly beneficial for human health, as phenols are useful for skin ultraviolet (UV) protection. In this investigation, we evaluated the safety and clinical efficacy of a sunscreen system containing a grape pomace extract from Vitis vinifera L. as a bioactive ingredient. The recovery of phenolics in the waste was performed by percolation. Nine emulsions were developed using a factorial design and two were evaluated clinically: Formulation E, containing only UV filters (butylmethoxydibenzoyl methane, ethylhexyl methoxycinnamate and ethylhexyl dimethyl PABA), and F, with the extract at 10.0% w/w + UV filters. The antioxidant activity was determined by the DPPH assay and the in vitro efficacy was established by sun protection factor (SPF) measurements (Labsphere UV-2000S). Clinical tests were performed to determine safety (human repeated insult patch test) and to confirm efficacy (photoprotective effectiveness in participants). The results showed a synergistic effect between the sunscreen system and the extract on UVB protection and antioxidant activity. Both samples were considered safe. Formulation F was 20.59% more efficient in protecting skin against UVB radiation, taking approximately 21% more time to induce erythema compared to the extract-free sample.

The chronological skin aging is a progressive and natural process with genetic and physiological changes. However, ultraviolet (UV) radiation may accelerate the oxidative stress, generating carcinogenesis and photoaging. Natural compounds and their applications are considered a trend in the cosmetic market. The protein-based film-forming compounds play an important role, once it collaborates for the better distribution of sunscreens on the skin. Here we investigated the in vitro photoprotective effectiveness of sunscreens containing the hydrolyzed collagen associated with UVA, UVB and/or inorganic filters. Sunscreens were developed with octocrylene (7.5%), butyl methoxydibenzoylmethane (avobenzone) (3.0%) and/or titanium dioxide (5.0%), associated or not with the hydrolyzed collagen (3.0%). In vitro photoprotective effectiveness was determined in a Labsphere ® UV2000S by the establishment of the sun protection factor (SPF) and critical wavelength (nm) values. Physicochemical and organoleptic characteristics were also assayed. The hydrolyzed collagen subjectively improved the formulation sensory characteristics. However, this bioactive compound led to a decrease of the SPF values of the photoprotective formulations containing octocrylene alone and octocrylene + butyl methoxydibenzoylmethane + TiO 2. This inadequate interaction may be considered during the development of new sunscreens intended to contain protein-based components.

We investigated plausible reuse for the dermocosmetic industry of byproducts from the winemaking process of red grapes (Vitis vinifera L. cv. C. Sauvignon) through the evaluation of one extract (grape pomace extract, GPE) and two fractions (one chloroform, GPE-CHF; one ethyl acetate, GPE-EAF). The samples were characterized analytically by liquid chromatography (HPLC) using a NIH 3T3 fibroblast cell culture to verify a cytosafety profile in normal and stressful environment (presence of H2O2), and by using it in a sunscreen system to observe improvements in the in vitro efficacy by diffuse reflectance spectrophotometry with an integrating sphere. The HPLC results for GPE-EAF and GPE-CHF samples with the best profile of syringic and p-coumaric acids, quercetin, and trans-resveratrol were used in the further assays. GPE-EAF and GPE-CHF, both at 30.00 µg/mL, maintained the cell viability in the absence of H2O2 (normal condition). In the sequence, GPE-EAF and GPE-CHF were evaluated against the oxidative stressor H2O2 in NIH 3T3 cells. A sharp drop in viability was only observed for GPE-CHF, and cytotoxicity of GPE-EAF was considered absent even in a hostile environment. Since GPE-EAF previously developed the best results, its potential performance was investigated in a sunscreen system. The in vitro sun protection factor of the phytoderivative-free formulation was 9.0 + 2.5; by adding GPE-EAF at 10.0%, its efficacy was elevated to 15.0 + 2.5. Both samples suffered a negative effect after artificial ultraviolet exposition (500 W/m2); however, the presence of GPE-EAF improved the photostability of the sunscreen system.