Sunscreen Formulations Research Articles

Photoprotection-related properties of a raw extract from Gordonia hongkongensis EUFUS-Z928: A culturable rare actinomycete associated with the Caribbean octocoral Eunicea fusca.

UV filters in current sunscreen formulations can have negative effects on human health, such as endocrine disruption and allergic reactions, as well as on the environment, including bioaccumulation and coral health toxicity. As a result, there is a need to find alternative compounds that serve as safer and more ecofriendly active ingredients. This study successfully isolated actinomycetes from the octocoral Eunicea fusca and assessed their potential as producers of photoprotective compounds. The use of bio-based chemical agents, particularly natural products, has been a highly effective strategy for discovering bioactive compounds, especially in marine invertebrates and their associated microbiota. Eighteen bacterial isolates were obtained and subsequently employed to prepare raw methanolic extracts from seven-day submerged cultures in Zobell marine broth. The resulting extracts were screened for 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity and characterized by total phenolic and flavonoid content measurements. After screening, the Gordonia hongkongensis EUFUS-Z928-derived raw extract exhibited the best antioxidant profile, i.e. DPPH and ABTS radical scavenging of 4.93 and 6.00 µmol Trolox per gram of extract, respectively, and selected for further photoprotection-related analysis. Thus, this extract demonstrated a UV-absorbing capacity of 46.33% of the in vitro sun protection factor calculated for 30 µg/mL oxybenzone but did not exhibit any cytotoxicity on human dermal fibroblasts (HDFa cell line) at concentrations up to 500 µg/mL. The liquid chromatography-mass spectrometry chemical characterization of this extract showed compounds with structural features associated with free radical scavenging and UV absorption (i.e. photoprotection-related activities). These findings highlighted the potential of the microbiota associated with E. fusca and confirmed the feasibility of exploiting its metabolites for photoprotection-related purposes.

Synthesis of an AVB@ZnTi-LDH composite with synergistically enhance UV blocking activity and high stability for potential application in sunscreen formulations

1-(4-(1,1-Dimethylethyl)phenyl)-3-(4-methoxyphenyl)-1,3-propanedione (known as Avobenzone/AVB), widely used throughout the world as a highly effective UVA absorber, can prevent the progression of photoaging in skin, and is also known for the disadvantage of having a reduced capability to absorb UVA when exposed to sunlight for long periods. To address this challenge, ZnTi-CO3-LDH with a two-dimensional layered structure was used to improve stability and synergistically enhance UV absorption of AVB. A novel AVB loaded ZnTi-CO3-LDH (AVB@ZnTi-LDH) material was synthesized by reconstruction method and the loading content (LC) was about 46.8 % investigated by high-performance liquid chromatography (HPLC). A possible mechanism for the binding of AVB with the ZnTi-LDH surface was proposed. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations were used to confirm further the coordination between Zn on the layer and the oxygen atom of the carbonyl group of AVB. UV absorption and critical wavelength of AVB@ZnTi-LDH were superior to those of AVB and ZnTi-LDH precursors. Compared with pure AVB, the photodegradation rate was reduced from 15.06 % to 4.06 %. Especially in titanium dioxide, the decomposition rate was reduced from 29.75 % to 7.92 %. Furthermore, pure AVB often reacts with multivalent metal ions to induce an unpleasant color (light yellow to reddish brown), which is greatly mitigated with AVB@ZnTi-LDH. In this study, avobenzone was combined with hydrotalcite to prepare an organic-inorganic composite with excellent UV resistance and better stability, the composite has great promise for application in sunscreen cosmetics.

Preliminary Evaluation of Photoprotective Potential in Flowers of Osbeckia octandra (L.) DC. for Development of Herbal Sunscreen Formulations

Introduction: Excessive exposure to ultraviolet (UV) radiation of the solar spectrum is often linked with the onset of conditions like inflammation, photoaging, immunosuppression, hyperpigmentation, and photocarcinogenesis. Although synthetic sunscreens have emerged as protectants against this harmful UV radiation, there is an increasing demand for sunscreens of herbal origin, which are believed to have low side-effect profiles in comparison to their synthetic counterparts. In order to cater for this need, the present study aimed at developing herbal sunscreen formulations from flowers of Osbeckia octandra DC, a purple-coloured wildflower widely distributed across different geographical regions in Sri Lanka. Methodology: The UV filtering potency and subsequently, the sun protection factor (SPF) in the methanolic extract of O. octandra was initially determined. Thereafter this extract was incorporated into the aqueous cream base at 25%, 50%, and 75% (w/w) and the SPF values and photostability of the prepared formulations were evaluated. Results: The initial SPF value of the crude extract (39.91 ± 1.93) had hardly changed even after incorporating it at 75% into the aqueous cream base. This 75% formulation surpassed the other two formulations and the commercial sunscreen (positive control) in terms of the higher SPF and broader spectrum of UV absorption. Its SPF value altered only slightly during the storage for 21 days in light or dark conditions and was photostable. Conclusion: Our preliminary observations demonstrated the appropriateness of O. octandra for the formulation of herbal sunscreens at the commercial stage. Keywords: Herbal sunscreens, Osbeckia octandra, Photoprotection, Sun protection factor, UV radiation

Milk thistle extracts could enhance the UV-protection efficiency and stability of mineral filters in sunscreen formulations

This paper was aimed to determine the total silymarin content, total antioxidant capacity, free radical scavenging activity of methanolic extracts obtained by ultrasonic assisted extraction of defatted milk thistle fruits, as well as to evaluate the sunscreen activity of the cream formulation containing milk thistle extract (MTE) using in vitro SPF method. Antibacterial and antibiofilm effect of extract was also evaluated. Moreover, the probable mode of action for the antioxidant activity of the extract detected via the in vitro assay was explored through molecular docking and molecular dynamics (MD) simulation. The total amount of silymarin in MTE was determined spectrophotometrically as silibinin equivalent. While the total antioxidant capacity of MTE and cream containing MTE was determined by the copper ions (Cu2+) reducing antioxidant capacity (CUPRAC) method, the radical scavenging capacity was determined by the 1,1-diphenyl-2-picryl-hydrazil (DPPH) method. Total tocopherol content was determined spectrophotometrically. In the present study, the amount of silymarin in the MTE was determined as 330.19 ± 1.95 mg silibinin equivalent/g-extract. The CUPRAC and DPPH values of MTE were calculated to be 2.49 ± 0.03, 0.675 ± 0.0006 mmol TE/g-extract, respectively, while the CUPRAC and DPPH values of the cream containing MTE were 0.327 ± 0.003, 0.156 ± 0.0006 mmol TE/g-cream, respectively. The total tocopherol content of the oils of milk thistle fruits was found to be 383.43 mg/kg oil. According to microbial tests results the MIC values of S. aureus and E. coli was detected 0.15625 and 0.3125, respectively. And inhibition rate of extract on biofilm formation on P. aeruginosa PAO1 was found 33 % rate. The molecular docking study demonstrated that the major constituent, silibinin, had a high potential of binding to the human peroxiredoxin 5. On the other hand, the MD simulation of the enzyme-silibinin complex revealed that the compound could be unstable in the binding region of the enzyme. The addition of MTE, which has antioxidant properties, to creams improved its effectiveness on sun protection and contributed to obtaining high SPF values. At the end of day 28 under accelerated test conditions, the combination of ZnO and MTE exhibited greater ability for sun protection compared to the cream containing ZnO as a sun filter agent. Additionally, milk thistle extracts is an ideal filter agent as an ingredient in sunscreens.

Tailored engineering of rod-shaped core@shell ZnO@CeO2 nanostructures as an optical stimuli-responsive in sunscreen cream

The catalytic efficiency of the materials can be boosted with the selective designing (nanostructures) including the core@shell which aids in attaining the separation of photoinduced charge carriers. However, to effectively separate the carriers and reduce the rate of recombination, tuning the thickness of the shell wall is a vital one. The one-dimensional (1D) rod-like shell wall-controlled ZnO@CeO2 core@shell structures were successfully prepared via co-precipitation and hydrothermal methods using the hexamethylenetetramine (HMTA) as a reagent. The CeO2 shell wall thickness was fine-tuned between 15 and 70 nm with a variation in the concentration of HMTA reagent. The results revealed that the concentration of HMTA played a significant role in the formation of ZnO@CeO2 core@shell structures and in tuning their thickness. The FE-SEM images evidenced the core-shell structures formation with the specific thickness and uniformity. The HR-TEM images confirmed the homogeneity and regular form of the shell thickness. The unit cell and crystallite size were identified from the XRD analysis. The constructed core-shell structures were further employed in the formula of the prototypes of sunscreen and their photoprotective performance was analyzed in the view to cut the solar light irradiation in a new sunscreen formulation. The developed core-shell ZnO@CeO2 structures showed the excellent optical absorption in both the UV as well as visible regions.

A Comprehensive Study on Formulation of Herbal Sunscreen Using Aloe barbadensis, Cucumis sativus and Solanum lycopersicum

Sunscreen formulations play a crucial role in protecting the skin from the harmful effects of ultraviolet (UV) radiation. Recent advancements in nature and herbal ingredients have led to a surge of interest in formulation effective, eco-friendly sunscreens. This review provides a comprehensive analysis of herbal sunscreen formulations, specially focusing on Aloe barbadensis miller (Aloe vera), Cucumis sativus (Cucumber), and Solanum lycopersicum (Tomato) as key ingredients. Aloe vera, known for its soothing and hydrating properties, offers potential benefits enhancing the skin’s resilience against UV damage. Cucumis sativus contributes cooling and antioxidant effects, while Solanum lycopersicum provides substantial levels of lycopene, which is recognized for its photoprotective qualities. The review systematically examines the phytochemical profiles, extraction methods, and efficacy of these ingredients in sunscreen formulations. It also explores their synergistic effects when combined and evaluates their overall performance in terms of sun protection factor (SPF), stability, and skin compatibility. By synthesizing current research findings, this review aims to highlight the potential of these herbal components in developing effective, natural sunscreens and to provide insights for future research and formulation strategies in the field of dermatological protection.

Recent developments in sunscreens based on chromophore compounds and nanoparticles.

Sunscreen formulations have undergone significant advancements in recent years, with a focus on improving UV radiation protection, photostability, and environmental sustainability. Chromophore compounds and nanoparticles have emerged as key components in these developments. This review highlights the latest research and innovations in chromophore compounds and nanoparticle-based sunscreens. It discusses the role of nanoparticles, such as zinc oxide and titanium dioxide, in scattering and absorbing UV radiation while remaining cosmetically acceptable. Chromophore compounds, encapsulated in nanoparticles, are explored for their potential to enhance UV protection by absorbing specific wavelengths of light. Additionally, advances in photo-stability, broad-spectrum protection, antioxidant inclusion, and biodegradability are discussed. The evolving landscape of sunscreen technology aims to provide more effective and environment-friendly solutions for safeguarding skin from the sun's harmful effects.

Boosting the effectiveness of UV filters and sunscreen formulations using photostable, non-toxic inorganic platelets.

We have studied the size-dependent optical scattering of aqueous suspensions containing Mg2Al-LDH platelets, which exhibit high total- and side-scatterings. By incorporating 3 wt% Mg2Al-LDH platelets (280 nm) in a commercial sunscreen formulation, we achieved a twofold Sun Protection Factor boost, providing a promising, high-efficient and non-toxic strategy to enhance sunscreen effectiveness.

The structural characterization and UV-protective properties of an exopolysaccharide from a Paenibacillus isolate.

Overexposure to ultraviolet (UV) light is known to cause damage to the skin, leading to sunburn and photo-aging. Chemical sunscreen products may give rise to health risks including phototoxicity, photosensitivity, and photosensitivity. Natural polysaccharides have attracted considerable interests due to diverse biological activities. A novel polysaccharide isolated was purified and structurally characterized using chemical methods followed by HPLC, GLC-MS, as well as 1D and 2D NMR spectroscopy. The photoprotective effect of the EPS on UVB-induced damage was assessed in vitro using cultured keratinocytes and in vivo using C57BL/6 mouse models. The average molecular weight of the EPS was 5.48 × 106Da, composed of glucose, mannose and galactose residues at a ratio of 2:2:1. The repeating units of the EPS were →3)-β-D-Glcp (1→3) [β-D-Galp (1→2)-α-D-Glcp (1→2)]-α-D-Manp (1→3)-α-D-Manp (1→. In cultured keratinocytes, the EPS reduced cytotoxicity and excessive ROS production induced by UVB irradiation. The EPS also exhibits an inhibitory effect on oxidative stress, inflammation, and collagen degradation found in the photodamage in mice. 1H NMR-based metabolomics analysis for skin suggested that the EPS partly reversed the shifts of metabolic profiles of the skin in UVB-exposed mice. The EPS exhibits skin photoprotective effects through regulating oxidative stress both in vivo and in vitro. Our findings highlight that the EPS is a potential candidate in sunscreen formulations for an efficient solution to UVB radiation.

Modulation of excimer formation and photostability of avobenzone inside the nanocavities of cyclodextrins

Avobenzone (AVZ), a UVA filter, is extensively used in sunscreen lotion and protects the skin from harmful UVA radiation. Despite their importance in sunscreen formulation, less attention has been given to its light induced excited state properties. Herein, we have explored the photophysical properties of AVZ in aqueous solutions and cyclodextrins (CDs) complexes by employing steady-state, time-resolved fluorescence, and molecular modelling tools followed by photostability analysis. AVZ exhibits dual emission from monomer and excimer forms in aqueous solutions. Spectroscopic studies revealed that AVZ forms multiple inclusion complexes with β-CD and γ-CD depending upon the host’s cavity size. These versatile host–guest complexes resulted in the modulation of the excimer formation of AVZ. The presence of α-CD and β-CD complexes with AVZ inhibited the excimer forms. In contrast, γ-CD facilitated excimer formation because its larger cavity could encapsulate the AVZ dimer. Stoichiometry and association constants for multiple host–guest complexes were determined using Benesi-Hildebrand (BH) plot. Job’s plot was used to confirm the stoichiometry of complexes. Time correlated single photon counting (TCSPC) technique was used to depict the excited state lifetime values of AVZ:CD inclusion complexes. Furthermore, these inclusion complexes were characterized by Fourier transform-infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Molecular docking followed by semiempirical calculations confirm the experimental results on stoichiometries and binding constants of host–guest complexes. UV light-induced absorption kinetics revealed that the photostability of AVZ inside the β-CD cavity is much better than other inclusion complexes of CDs. Overall, the present study helps us in further understanding of excited state behavior of AVZ inside hydrophobic nanocavities.

Nanotechnology's Application in Cosmetics: Dermatology and Skin Care Items

Nanotechnology has emerged as a revolutionary force in various fields, and its application in cosmetics has significantly transformed the landscape of dermatology and skin care. This abstract explores the multifaceted impact of nanotechnology on cosmetic products, focusing on its potential to enhance efficacy, improve delivery systems, and address specific dermatological concerns. Integrating nanotechnology into cosmetics offers a notable advantage by enabling precise control of materials at the nanoscale. This capability leads to the creation of formulations that exhibit enhanced bioavailability. The use of nano-sized particles, typically measured in nanometers, improves the penetration of active ingredients into the skin, ensuring precise delivery and increased absorption. This precision has paved the way for the development of highly effective skincare products capable of addressing specific skin conditions such as hyperpigmentation, fine lines, and acne. Furthermore, nanotechnology has revolutionized the formulation of sunscreens, offering transparent and cosmetically elegant options that provide superior protection against both UVA and UVB rays. Nano-sized titanium dioxide and zinc oxide particles scatter light more effectively, offering broad-spectrum coverage without the white residue associated with traditional sunscreens. Enhanced visual appeal motivates consistent application of sunscreen, fostering improved skin well-being and diminishing the likelihood of skin damage caused by sun exposure. In the realm of dermatology, nanotechnology has played a pivotal role in propelling forward groundbreaking therapeutic strategies. Nanoparticles are utilized to encapsulate and transport active components, including vitamins and antioxidants, ensuring their stability and prolonged release. This targeted approach allows for the customization of skincare regimens based on individual skin needs, thereby optimizing treatment outcomes for various dermatological conditions. Despite the remarkable advancements facilitated by nanotechnology, concerns have been raised regarding the safety of nano-sized particles in cosmetics. Addressing these concerns is crucial to ensure consumer confidence and regulatory compliance. Thorough testing and extensive research are crucial for a comprehensive evaluation of the safety characteristics of nanomaterials, taking into account factors such as particle size, surface charge, and potential interactions with the skin. In summary, the integration of nanotechnology into cosmetics marks a new era of innovation in dermatology and skincare. It not only enhances the delivery of active ingredients but also improves the effectiveness of sunscreens, presenting a promising path for the advancement of cutting-edge cosmetic formulations. As research in this field advances, it is essential to find a balance between innovation and safety, ensuring that nanotechnology continues to positively influence the cosmetics industry while prioritizing the well-being of consumers.

Hybrid systems based on avobenzone–wrinkled mesoporous silica as ingredients of sunscreen formulations

Excessive exposure to solar radiation causes skin reddening, and sunburn, may accelerate photoaging processes, and lead to neoplastic changes. Therefore, it is recommended to apply cosmetic formulations containing UV protection filters. In recent years, doubts have arisen regarding the safety of certain chemical sunscreen agents that can penetrate the deeper layers of the skin, undergo photodegradation, generate allergies, and affect the endocrine system. The aim of this study was to develop a strategy to limit the permeation of avobenzone from emulsions. Wrinkled mesoporous silicas modified with zinc oxide and/or aminosilane were synthesized, characterized, and next applied as the carriers for the selected UV filter – avobenzone. The introduction of organic groups and ZnO did not disturb the wrinkled morphology of materials, but it changed the textural parameters due to the blocking of micropores. The modification of the wrinkled mesoporous silica had a positive effect on reducing avobenzone rate of desorption. The smallest amount of avobenzone was released from wrinkled mesoporous silica modified with zinc oxide. The release of avobenzone from nanocarriers followed the Korsmeyer-Peppas model, while the diffusion from emulsion was based on the Higuchi model. It was proved that the introduction of avobenzone to functionalized wrinkled mesoporous silica materials reduced the diffusion process of avobenzone from cosmetic emulsions. Nanoporous carriers may help solve the problems related to transepidermal penetration and the potential impact of UV filters on the endocrine system.

Fish gut and skin microbiota dysbiosis induced by exposure to commercial sunscreen formulations

UV filters (organic or mineral) present in sunscreen products are emerging contaminants of coastal aquatic environments. There is an urgent need to understand marine organisms responses to these compounds. In this study, we investigated the effect of exposure to dilutions of commercial sunscreen formulations on bacterial communities of mullet (Chelon sp.). The gut and skin mucus microbial communities were characterized using a metabarcoding approach targeting the 16S rRNA gene. Our results revealed that mullets had its own bacterial communities that differ from their surrounding habitats and specific to tissue. The dilutions of commercial sunscreens modified the relative abundance of Actinobacteroita, Bacteriodota and Proteobacteria for both gut and skin microbiota. They also allowed to bacteria affiliated to Mycobacterium, Nocardia and Tenacibaculum genera, known to house pathogenic species, to colonize the epithelium which may have implications for fish host health.

Evaluation of the protection of sunscreen products against long wavelength ultraviolet A1 and visible light-induced biological effects.

Long wavelength ultraviolet-A1 in combination with visible light induces hyperpigmentation, particularly in dark-skin phototypes. This study evaluated the efficacy of four sunscreen formulations in protecting against VL + UVA1 (370-700 nm). The test products (A-D) were applied to the back of 12 volunteers, then irradiated with 320 J/cm2 VL + UVA1 (3.5% UVA1 [370-400 nm]). Immediately after irradiation, and at Days 1, 7, and 14, erythema and pigmentation were assessed by investigator global assessment (IGA), colorimetry (Δa* and ΔITA) and diffuse reflectance spectroscopy (DRS)-measured relative dyschromia (area under the curve AUC). Control areas were irradiated without sunscreen. Product D, containing titanium dioxide 11%, iron oxides 1%, and antioxidants, provided the highest and most consistent protection. Compared with unprotected irradiated control, it had statistically significantly less erythema on IGA, DRS (Δoxyhemoglobin), and colorimetry (Δa*) at Day 0; less pigmentation on IGA at all time points, on DRS (relative dyschromia) at Days 7 and 14, and on colorimetry (ΔITA) at Day 0. Product B, containing zinc oxide 12% plus organic UV filters, iron oxides 4%, and antioxidants, also showed some efficacy. Of the sunscreens tested, the tinted products provided better protection against VL + UVA1 than the non-tinted products. Since the product with 1% iron oxides was superior to the product with 4% iron oxides, further studies are needed to evaluate whether iron oxide content correlates with better protection.

Efficacy and Tolerability of a Sunscreen Containing Licochalcone a and L-Carnitine as an Adjunct to Retinoids in the Management of Acne and Post-Acne Pigmentation Among Malaysian Patients.

We aim to evaluate the effectiveness and tolerability of a sunscreen formulation containing licochalcone A (LicA) and L-carnitine (LC) as an adjuvant to adapalene in the management of acne and post-acne pigmentation (PAH). A randomized, double-blind, active comparator-controlled trial of 51 patients aged 18 years or older with a clinical diagnosis of mild-to-moderate acne vulgaris was conducted at the Hospital Sultan Abdul Aziz Shah, Universiti Putra Malaysia. The efficacy and tolerability of once-daily adapalene 1.0% were assessed during the 2-week run-in period. Subsequently, patients were randomized to receive either an add-on investigational LicA-containing sunscreen or niacinamide-containing comparator sunscreen every 4 hourly during daytime for 4 weeks. Patients were followed up at Weeks 2 and 4 to assess for improvement in acne severity, PAH, calorimetric parameters and cutaneous tolerability. Two weeks of adapalene usage significantly improved acne severity; however, up to 52% of patients experienced dryness, burning and stinging. Adding LicA-containing or comparator sunscreens was associated with further improvement in acne severity, PAH and calorimetric parameters at the study endpoint. No significant differences in the cutaneous tolerability profiles were observed between treatment groups. Notably, significantly fewer patients receiving LicA-containing sunscreen developed scaliness at Week 4 compared with those in the comparator group. In addition, more patients receiving LicA-containing sunscreen reported less dryness, burning and stinging reactions than the comparator group. Importantly, more patients receiving LicA-containing sunscreen agreed that their treatment led to excellent improvement than the comparator group; of note, one patient reported that their condition worsened with the receipt of the comparator product. The concurrent use of LicA-containing sunscreen with adapalene may improve the cutaneous tolerance to adapalene among Malaysian patients.

Balance of Lignin Light-Color and UV-Shielding Properties: Pyruvic Acid Fractionation for Green Sunscreen Formulations

Balance of Lignin Light-Color and UV-Shielding Properties: Pyruvic Acid Fractionation for Green Sunscreen Formulations

Zn2SnO4 ternary metal oxide for ultraviolet radiation filter application: a comparative study with TiO2 and ZnO

ABSTRACT Ultraviolet (UV) radiation causes serious health risks. Inorganic metal oxides, such as titanium dioxide (TiO2) and zinc oxide (ZnO), have long been recognized for their effectiveness as UV radiation filters/blockers in sunscreen formulations. TiO2 and ZnO as UV-blocking materials have some limitations and issues such as producing harmful radicals and toxicity, respectively. As a result, there is a growing need to develop efficient and safe UV-blocking materials to overcome these limitations associated with the conventional TiO2 and ZnO materials. Zinc stannate (Zn2SnO4), as a ternary metal oxide, is expected to be a promising candidate due to its optical properties and potential for UV-blocking capability. This study presents a comprehensive investigation into the development and characterization of Zn2SnO4 as a potential alternative UV filter to TiO2 and ZnO. The fundamental characteristics, including structural, optical, and photocatalytic characteristics, as well as cell viability, were investigated for two Zn2SnO4 morphologies: cubic aggregate Zn2SnO4 nanoparticles (ZTO CANP) and Zn2SnO4 nanoparticles (ZTO NP), which were compared with the performance of TiO2 nanoparticles (TiO2 NP) and ZnO nanoparticles (ZnO NP). Interestingly, in addition to their promising UVB and partial UVA blocking properties, ZTO CANP and ZTO NP were found to be relativity photocatalytically inactive materials, which means they produce less free radical species as in the case of TiO2 NP, and they cannot be considered as toxic materials as in the case of ZnO NP. To the best of our knowledge, this is the first direct comparison study examining the performance of Zn2SnO4 ternary metal oxide for its potential use as a UV filter. Further research and optimization need to be conducted on these materials, particularly on ZTO CANP as a promising alternative UV filter.

NATURAL KOSMETIK BERBAHAN EKSTRAK CAIR PROPOLIS SEBAGAI AGEN TABIR SURYA DALAM SEDIAAN LOTION DENGAN VARIASI ASAM STEARAT SEBAGAI EMULAGTOR

Sunscreen is a preparation used on the surface of the skin that works to absorb, scatter or reflectrays ultraviolet. One of the compounds that have benefits as a sunscreen is propolis. Propolis has antioxidant activity and its components can be used as a sunscreen formulation. The flavonoids contained in propolis have potential as sunscreen because of the presence of a chromophore group (conjugated double bond) which can absorb both UV B and UV A rays. To make a good preparation, a good formula is needed, one of the components in making lotions is acid. stearicate used as emulgator. This study aims to formulate a lotion with variations of stearic acid which functions as anas emulgator well as to test the physical and chemical properties of thepreparations lotion. The lotion is made in three variations of the composition of stearic acid, namely 2.5%: 5%; 7.5%. The lotion obtained was evaluated for the physical and chemical properties of thepreparation lotion including organoleptic test, homogeneity, emulsion type, pH, spreadability, adhesion and viscosity as well asmeasurement of the SPF value in vitro. The results of the analysis showed that variations in the concentration of stearic acid had a significant effect on the physical properties of the lotion including the results of pH, spreadability, adhesion, and viscosity. Stearic acid the higher the viscosity, consistency, and increased adhesion but the spreadability decreases. The SPF test results on theformula were lotion 6.13 (F1), 6.11 (F2), and 6.05 (F3) and the SPF value decreased after thetest freeze thaw.

Evaluation of cytotoxic and genotoxic potential of avobenzone and octocrylene on human skin fibroblast cells

We investigated the cytotoxic and genotoxic effects of the organic UVA filter avobenzone (AVB), and the UVB filter octocrylene (OCT), found alone or in combination in different sunscreen formulations, on normal human skin fibroblast cells (CCD-1118Sk). To achieve this purpose, we used XTT viability assay, single cell gel electrophoresis (comet) assay and reactive oxygen species (ROS) assay. For cytotoxicity, CCD-1118Sk cells were exposed to various concentrations of AVB (32–800 µM), and OCT (130–6500 μM). The IC50 values were 100.2 and 1390.95 µM for AVB and OCT, respectively. IC12.5, IC25 and IC50 concentrations were chosen for genotoxicity testing. The comet assay revealed DNA damage at the two highest concentrations of AVB and all OCT concentrations. The rate of DNA damage was significantly higher than in the control groups. Co-treatment with AVB and OCT increased the level of DNA damage and intracellular oxidative stress compared with AVB and OCT treatment alone. Finally, our study showed that the UVA filter AVB, with the UVB filter OCT, may induce cytotoxic and genotoxic effects on human skin fibroblast cells. Highlights Avobenzone and octocrylene are UV filters used in sunscreen products. Healthy human skin fibroblast cell line CCD-1118Sk was used for cytotoxic and genotoxic assays. Cotreatment with avobenzone and octocrylene caused more severe DNA damage than their treatment alone. Our findings will contribute to the limited number of cytotoxicity and genotoxicity studies and lead to more detailed studies on the use of these two chemicals.

Sunscreens can preserve human skin microbiome upon erythemal UV exposure.

Ultraviolet radiation (UVR) is a known environmental key factor for premature skin ageing. Only few scientific evidence is available to support the effects of UVR on the skin microbiome. This in vivo pilot study aimed to evaluate the impact on the skin microbiome upon erythemal UV exposure and the protection of UV-exposed skin microbiome by UV filters. Ten female volunteers were treated with an sun protection factor (SPF) 20 sunscreen and placebo formulation (without UV filters) on their upper middle backs and irradiated with an erythemal dose (2 MED) by a solar simulator. Skin swabbing samples from four zones (i.e., unexposed, exposed, sunscreen- and placebo-treated on exposed skin) were collected for the microbiome analysis before and 2 h after UV exposure, respectively, and processed via shallow 16S rRNA Amplicon and Shotgun metagenomic sequencing. An in vitro UV method was developed to confirm the protection of isolated bacterial strains by single UV filters and combinations. Alpha diversity was impacted by significant inter-individual differences and by treatment rather than by irradiation. Cutibacterium acnes was found to be the most abundant and a confounding factor for diversity. On a species level, Lactobacillus crispatus was negatively associated with UVR and placebo treatment, whereas there was a positive association with sunscreen treatment. The sunscreen treatment also favoured an interaction network with central Micrococcus genus. The in vitro results showed that both single UV filters and combinations had specific effects on the survival rates of L. crispatus, C. acnes, and Staphylococcus epidermidis. We identified potential microorganisms and bacterial interactions that were associated with an SPF 20 sunscreen treatment. The specific protection of L. crispatus as a key player in the UV-exposed skin microbiome and reduction of C. acnes population by UV filters might lead to new cosmetic concepts for photoprotection.