Overexposure to ultraviolet radiation mainly leads to skin disorders (erythema, burns, immunosuppression), skin aging, and skin cancer as the most serious side effect. It has been widely accepted that using sunscreen products is an important way to protect against the harmful effects of UV rays. Although commercial sunscreens have constantly changed and improved over time, there are emerging concerns about the safety of conventional, organic, UV filters due to adverse effects on humans (such as photoallergic dermatitis, contact sensitivity, endocrine-disrupting effects, etc.) as well as accumulation in the environment and aquatic organisms. This is why natural compounds are increasingly being investigated and used in cosmetic and pharmaceutical sunscreens. Some of these compounds are widely available, non-toxic, safer for use, and have considerable UV protective properties and less side effects. Plant-based compounds such as flavonoids can absorb UVA and UVB rays and possess antioxidant, anticarcinogenic, and anti-inflammatory effects that contribute to photoprotection. Apart from flavonoids, other natural products such as certain vegetable oils, carotenoids, stilbenes, and ferulic acid also have UV-absorbing properties. Some vitamins might also be beneficial for skin protection due to their antioxidant activity. Therefore, the aim of this research was to gain insight into the potential of natural compounds to replace or reduce the amount of conventional UV filters, based on recent research.

Novel delivery systems for cosmetics, drugs, and food ingredients are of great scientific and industrial interest due to their ability to incorporate and protect active substances, thus improving their selectivity, bioavailability, and efficacy. Emulgels are emerging carrier systems that represent a mixture of emulsion and gel, which are particularly significant for the delivery of hydrophobic substances. However, the proper selection of main constituents determines the stability and efficacy of emulgels. Emulgels are dual-controlled release systems, where the oil phase is utilized as a carrier for hydrophobic substances and it determines the occlusive and sensory properties of the product. The emulsifiers are used to promote emulsification during production and to ensure emulsion stability. The choice of emulsifying agents is based on their capacity to emulsify, their toxicity, and their route of administration. Generally, gelling agents are used to increase the consistency of formulation and improve sensory properties by making these systems thixotropic. The gelling agents also impact the release of active substances from the formulation and stability of the system. Therefore, the aim of this review is to gain new insights into emulgel formulations, including the components selection, methods of preparation, and characterization, which are based on recent advances in research studies.

Grape pomace is a by-product abundant in phenolic compounds that can be used in the food, cosmetic, and pharmaceutical industries. For the efficient extraction of such compounds, an aqueous solution of non-ionic surfactant Brij S20 was applied as a green extraction medium, and the optimization was performed using surface response methodology. The effects of four independent factors (surfactant concentration, time, pH, and solvent-to-material ratio) were evaluated, and total phenolic content (TPC), DPPH radical inhibition, and selected polyphenol compound concentrations were analyzed as responses. Using response surface methodology (RSM), five regression equations were derived and good adequacy of the models was confirmed. The solvent-to-material (SM) ratio was the most influential factor. Surfactant concentration of 3% (m/V), extraction time of 120 min, pH value of 4.06, and SM ratio of 50 mL/g were determined as optimum conditions to maximize all responses. Under the optimal conditions, the mean validated values obtained for TPC, DPPH, gallic acid, catechin, and quercetin concentrations were 968.50 ± 37.06 mg GAE/L, 61.41 ± 7.13%, 5.10 ± 0.05 mg/L, 10.62 ± 0.79 mg/L, and 6.04 ± 0.10 mg/L, respectively. Furthermore, the established conditions were applied for the extraction of phenolic compounds from grape pomace of four grape varieties. The proposed extraction method proved effective, providing extracts rich in polyphenols suitable for further applications.

Background: Zinc oxide paste is traditionally compounded and applied in the therapy of various skin conditions. However, prolonged use of talc, usually present in zinc oxide pastes, may pose health risks due to potential contamination with asbestos and quartz, highlighting the need for alternative excipients. This study aimed to examine the effects of starches from various botanical sources and their particle size on the rheological and absorption properties of zinc oxide paste. Methods: Eight zinc oxide paste formulations were prepared, containing 25% zinc oxide and 25% indifferent excipient (talc, tapioca, rice, or maize starch) in two particle sizes. Rheological properties were assessed using amplitude and frequency sweep tests, and water- and oil-absorption capacities were determined using a centrifugation-based method. Results: Amplitude sweep tests confirmed the predominant solid-like nature of zinc oxide pastes, with the elastic modulus (G′) exceeding the viscous modulus (G″) in all formulations. Tapioca starch-based pastes exhibited the highest G′ and G″ values, while talc-based pastes exhibited the lowest. Frequency sweep tests showed that pastes were resistant to structural changes under stress, with G′ consistently dominating over G″ across the entire frequency range. Tapioca starch-based formulations exhibited the highest water-absorption capacity, while the talc-based formulations had the highest oil-absorption capacity. Reducing particle size improved both water- and oil-absorption capacities. Conclusions: Starches may be considered as alternatives to talc in zinc oxide pastes, due to their ability to modify the absorption and rheological properties of pastes. Future studies should assess the impact of starch substitution on sensory characteristics, shelf-life stability, and patient satisfaction.

Tragacanth gum (TRG) and gum arabic (GA) are natural anionic gums with heterogeneous and distinctive macromolecular content. The aim of this study was to gain insight into interactions between compounds in TRG/GA mixtures and to clarify the physicochemical phenomena that occur. The following methods were used for this purpose: surface tension, fluorescence, viscosity and particle size measurements. Furthermore, the various solutions were monitored for phase separation. Surface tension measurements revealed that TRG had a lower critical aggregation concentration (CAC) value compared to GA (0.130% vs. 1.626%, respectively), and that with increasing TRG mass fraction in the mixtures, the CAC values decreased. The same trend was observed with overlapping concentrations (c*). Namely, c* values for TRG and GA were 0.224% and 3.297%, respectively, and the increase in TRG mass fraction caused the c* values to decrease. Additionally, it was noticed that the experimentally obtained values of specific viscosity deviate from the additive rule. The phase separation observation and the analysis of a separated phase indicated the formation of a coacervate-like phase, beginning at 2% GA in mixtures, around the CAC of GA. The mechanism responsible for the onset of these aggregates was proposed, as well as the compounds implicated in their emergence, and particle size analysis further highlighted complex interactions between TRG and GA. The results of this study could be used to guide the development of novel food, pharmaceutical, cosmetic and chemical products based on natural ingredients.