Absorption Of UV Radiation Research Articles

1,3-Naphthoxazine derivatives: Synthesis, in silico pharmacokinetic studies, antioxidant and photoprotective properties

Investigation into the interactions between photoprotective agents and skin can offer a precise understanding of their biological behaviors in vitro and in vivo, providing crucial insights for generating new substances. For this purpose, we designed and synthesized a series of naphthoxazine derivatives and examined their photoprotective properties. 1,3-naphthoxazine derivatives were synthesized through the multi-component reaction of 2-naphthol, arylamines and aromatic aldehydes in the presence of copper(II) trifluoromethanesulfonate (Cu(OTf)2) and (±)-Camphor-10-sulfonic acid ((±)-CSA) catalyst system under sonication. The potential of these synthesized 1,3-naphthoxazine derivatives as antioxidants and viable organic structural-based sunscreen ingredients has been investigated. Sun protection factor (SPF) assay results showed that especially compounds 4i, 4c, 4k, 4d, 4r, and 4h had remarkably high activity (23.65, 23.57, 23.04, 21.94, 20.80, and 20.26, respectively at 900 µg/mL concentration). Additionally, antioxidant activity of the synthesized compounds was evaluated and compounds 4h, 4e, 4b, and 4j exhibited the highest activities in DPPH scavenging activity assay (86.46 %, 82.83 %, 80.78 %, and 80.65 % respectively at 400 µg/mL concentration). The synthesized compounds exhibit promising characteristics for effective UV radiation absorption, suggesting their suitability for inclusion in sunscreen formulations. Cytotoxic activity of compound 4k against normal human fibroblast cell line (MRC-5) was determined by CVDK-8 method. The results revealed that the compound provided remarkable viability (87.55 %) of MRC-5 cells at concentration of 100 µM. The study explores their efficacy in providing broad-spectrum protection against UVA and UVB rays, degradation and photostability, ADMET profile, and other pharmacokinetic properties.

Chemical composition and potential pharmacological applications of Centaurea acaulis L.

Our study aimed to characterize the composition of the ethyl acetate extract obtained from Centaurea acaulis L. and assess its dermatoprotective and antioxidant properties. The secondary metabolite composition was established by high-performance liquid chromatography combined with mass spectrometry. The antioxidant activity was assessed using four different assays, including DPPH, β-carotene, CUPRAC, and reducing power assays. Furthermore, the in vitro photoprotective effect was evaluated by measuring sun protection. The HPLC-TOF/MS analysis identified the presence of 19 bioactive compounds in the ethyl acetate extract. Major components such as rosmarinic acid and 4-hydroxy benzoic acid were detected, along with other compounds including caffeic acid, cichoric acid, gentisic acid, p-coumaric acid, protocatechuic acid, ferulic acid, vanilic acid, gallic acid, apigenin-7-glucoside, catechin, kaempferol, and quercetin. The ethyl acetate extract of Centaurea acaulis L. exhibited strong antioxidant activity in DPPH, β-carotene, CUPRAC, and reducing power assays, outperforming standard antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), tannic acid, and ascorbic acid. Additionally, the extract demonstrated a high ability to absorb UV radiation, with an average sun protection factor of 40.20 ± 0.11. These findings highlight the significant antioxidant and dermatoprotective potential of the ethyl acetate extract from Centaurea acaulis L., suggesting its potential use in cosmetic and dietary additive formulations.

Preparation and characterization of peptide-modified core-shell fibrous substrates with UV-blocking properties for corneal regeneration applications

Effective UV protection is a key aspect of substrates directly exposed to UV radiation. Therefore, in the present study, fibrous substrates of core–shell morphology (PCL-core, PVP-shell) containing peptides based on tryptophan, tyrosine and cysteine (W6, YYC2 and YYC3) were prepared. Spectrophotometric studies showed UV absorption by peptides containing tyrosine and tryptophan in the UVB (up to 80%) and UVA (up to 40%) ranges. Cysteine, in turn, contributed to high antioxidant properties, confirmed by DPPH assay. The presence of peptides contributed to a nonwoven fabric characterized by the ability to absorb UV radiation and prevent the occurrence of oxidative stress (caused by the presence of free radicals). In turn, the increase in the surface zeta potential of the nonwoven after UV irradiation and higher thermal stability (demonstrated by DSC studies) indicated the crosslinking of the PVP layer under UVR, which further contributes to the increased protection of the nonwoven against its effects. In summary, obtained nonwoven exhibited functional similarity to the native cornea, providing a potential solution for enhancing corneal tissue engineering and regenerative medicine applications.

Phenolic Constituents, Photoprotective Effect, and Antioxidant Capacities of Achillea ligustica All.

The present investigation was performed to figure out the chemical constituents and biological potential of polar extracts (AcOEt and BuOH) from Achillea ligustica, a medicinal species of the Asteraceae family. Liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) was utilized to conduct a preliminary analysis of the phytochemical profiles of the AcOEt and BuOH extracts. The analysis revealed the existence of twenty compounds in the AcOEt extract and twenty-two in the BuOH extract, classified into various types of secondary metabolites. Subsequently, the exudate from the plant yielded five flavonoids, including two 6-methoxyflavonols identified for the first time in this genus. The isolation of compounds from AcOEt and BuOH extracts was achieved through the combined use of column chromatography (silica gel and Sephadex LH-20) and preparative TLC chromatography. The structures have been elucidated using 1D and 2D NMR spectroscopy, alongside comparisons with research data. Our study measured the total phenolic and flavonoid contents and carried out a comprehensive range of antioxidant tests using DPPH, GOR, CUPRAC, reducing power, and O-phenanthroline assays. Both extracts exhibited considerable antioxidant potential and contained high levels of phenolic and flavonoid compounds. The photoprotective effect of the AcOEt and BuOH extracts was evaluated in vitro by measuring the sun protection factor. Both extracts exhibited a high capacity for UV radiation absorption. Consequently, this plant presents an intriguing prospect for future research focused on incorporating it into photoprotective cosmetic products and pharmaceutical formulations.

Characterization of Composite Film Containing Polyvinyl Alcohol Cross‐Linked With Dialdehyde Cellulose Using Citric Acid as a Catalyst for Sustainable Packaging

ABSTRACTThis study is aimed at fabricating composite films by cross‐linking polyvinyl alcohol (PVA) and dialdehyde cellulose (DAC) in varying ratios using citric acid as a catalyst. The acetal formation between the two components was studied using FTIR. Characterizations of the physiochemical properties revealed that increasing the DAC ratio of the composite film improved the hydrophobicity, tensile strength and barrier properties (water vapour, UV and oxygen) of the films while reducing elongation at break (flexibility), swelling and solubility of the film in water. When the DAC ratio was elevated to 50%, the tensile strength was enhanced to 98 MPa. In comparison, flexibility diminished to 29%, the solubility of the film reduced to 10% and water vapour permeability was lower by two orders of magnitude than that of the control PVA film. The peroxide value of linoleic acid decreased from 21.2% ± 7.6 (packed with PVA film) to 9.9% ± 0.9 (packed with 50% DAC composite film) after 15 days. Furthermore, the composite films demonstrated effective absorption of UV radiation, with the order of effectiveness being UV‐C > UV‐B > UV‐A radiation. No significant difference in biodegradability was detected in the composite films with an increase in DAC ratio during indoor soil burial tests for 30 days. This study implies that the composite film could serve as an alternative sustainable packaging option, especially when transparency and high oxygen barrier properties are desired.

Synthesis of a new Schiff base acceptor–donor molecule as a UV stabilizer for enhanced poly(lactic acid) (PLA) photoprotection

AbstractPoly(lactic acid) (PLA) is a biodegradable aliphatic polyester of significant interest. Owing to its traits, PLA stands out as one of the most widely used polymers in various fields. Nevertheless, environmental conditions, such as heat, UV light, and humidity have negative impacts on the polymer's performance as a result of the accelerating aging process. In this study, we present a novel acceptor–donor (AD) Schiff base molecule that demonstrates significant UV stabilization when incorporated into the polymer's matrix. The stabilization effect of the AD molecule was studied by using the weight loss method and tracking the functional group indices of CO (ICO) and OH (IOH) that emerge because of polymer degradation after irradiation with UV light for 300 h. The films' structures were studied by scanning electronic microscopy (SEM), atomic force microscope (AFM), and energy‐dispersive x‐ray spectroscopy (EDX) to evaluate the stabilization enhancement of AD moiety. The results exhibit a significant decrease in weight loss for blended PLA, in contrast to blank PLA. The weight loss percentage reduced from 2.5 for blank PLA to less than 0.7 for blended PLA. Furthermore, ICO and IOH indices witness a remarkable reduction which verifies the improved photodegradation resulting from AD moiety. The suggested method involves the efficient absorption of UV radiation produced during photo‐degradation by the AD molecule, which then emits this light as visible blue light without causing any damage to PLA film's chemical structure. Our results demonstrate the adaptability of AD molecules as PLA photo‐stabilizers and point to their wider significance for sustainable material applications. This work advances the stability of PLA films and provides opportunities for the creation of novel stabilization techniques based on organic electrical principles. Future studies may examine the multipurpose uses of the AD molecule in sensor materials and other contexts.Highlights Presenting a novel acceptor–donor Schiff base as a phot stabilizer of PLA. Using the weight loss method and tracking the functional group indices to test the degradation. A significant decrease in weight loss for blended PLA, in contrast to blank PLA. The Schiff base absorbing UV light, excited electrons from ground state to excited state. They return to the ground state and produce bright blue light. These movement of electrons cause no damage to the PLA polymer chains.

Exploring the Agricultural Applications of Microbial Melanin.

Microbial melanins are a group of pigments with protective effects against harsh conditions, showing fascinating photoprotective activities, mainly due to their capability to absorb UV radiation. In bacteria, they are produced by the oxidation of L-tyrosine, generating eumelanin and pheomelanin. Meanwhile, allomelanin is produced by fungi through the decarboxylative condensation of malonyl-CoA. Moreover, melanins possess antioxidant and antimicrobial activities, revealing significant properties that can be used in different industries, such as cosmetic, pharmaceutical, and agronomical. In agriculture, melanins have potential applications, including the development of new biological products based on this pigment for the biocontrol of phytopathogenic fungi and bacteria to reduce the excessive and toxic levels of agrochemicals used in fields. Furthermore, there are possibilities to develop and improve new bio-based pesticides that control pest insects through the use of melanin-producing and toxin-producing Bacillus thuringiensis or through the application of melanin to insecticidal proteins to generate a new product with improved resistance to UV radiation that can then be applied to the plants. Melanins and melanin-producing bacteria have potential applications in agriculture due to their ability to improve plant growth. Finally, the bioremediation of water and soils is possible through the application of melanins to polluted soils and water, removing synthetic dyes and toxic metals.

Tailoring optical properties and humidity sensing response of multilayered Tb(Sal)3Phen and Eu(DBM)3Phen complex nanofibres

In this work, we investigate the opto-humidity sensing and colour tuning in polyvinyl alcohol (PVA) polymeric electrospun nanofibres dispersed with Tb(Sal)3Phen (TSP) and Eu(DBM)3Phen (EDP) complexes. Fourier transform infrared spectroscopy, scanning electron microscopy, and photoluminescence analysis were used to thoroughly analyse the structural, morphological, and spectroscopic features of the synthesised nanofibres in single and stacked multilayer nanofibres. A spectroscopic analysis was performed on all configuration schemes. Under UV excitations, the synthesised TSP complex and EDP complex inhibited nanofibres yield green and red emission corresponding to 5D4→7Fj (j = 4, 5, 6) and 5D0→7Fj (j = 0, 1, 2, 3) transitions attributed to Tb3+ and Eu3+ ions, respectively. The EDP nanofibres presented better UV radiation absorption than TSP, which was attributed to higher absorptivity of DBM than Sal. Additionally, the photoluminescence intensity ratio of characteristic emission peaks i.e. 544 nm (5D4→7F5)/615 nm (5D0→7F2) is function of humidity exposure and excitation wavelength. The stacked multilayer nanofibres exhibit good response and recovery times, 35 and 52 s, negligible hysteresis, and cyclic stability.

Understanding Active Photoprotection: DNA-Repair Enzymes and Antioxidants.

The detrimental effects of ultraviolet radiation (UVR) on human skin are well-documented, encompassing DNA damage, oxidative stress, and an increased risk of carcinogenesis. Conventional photoprotective measures predominantly rely on filters, which scatter or absorb UV radiation, yet fail to address the cellular damage incurred post-exposure. To fill this gap, antioxidant molecules and DNA-repair enzymes have been extensively researched, offering a paradigm shift towards active photoprotection capable of both preventing and reversing UV-induced damage. In the current review, we focused on "active photoprotection", assessing the state-of-the-art, latest advancements and scientific data from clinical trials and in vivo models concerning the use of DNA-repair enzymes and naturally occurring antioxidant molecules.

Machine learning for authentication of black tea from narrow-geographic origins: Combination of PCA and PLS with LDA and SVM classifiers

This study investigates the feasibility of using UV–Vis spectroscopy coupled with machine learning methods to authenticate tea samples based on their geographical origins in a narrow longitudinal strip (200 km). Several preprocessing methods, such as standard normal variate (SNV), auto-scaling, multiplicative scatter correction (MSC), mean centring (MC), first derivative, and their combinations, were applied to eliminate the noninformative information. The partial least squares-linear discriminant analysis (PLS-LDA) model using first derivative spectra represented the following results, including 98.0% sensitivity, 99.5% specificity, and a mean accuracy of 98.0%. The support vector machine (PLS-SVM) classifier using first derivative spectra represented 94.0% sensitivity, 98.6% specificity, and a mean accuracy of 94.0%. The satisfactory results of the models depicted that the chemical components of tea, such as polyphenols, chlorogenic and fatty acids that absorb UV radiation are the chemical markers that can discriminate tea samples based on their geographical origin. Therefore, UV–Vis spectral fingerprinting combined with machine learning methods could be a practical, feasible, and simple method for classifying tea based on their geographical origins in a narrow longitudinal strip.

Secretory structures in Baccharis platypoda DC. inflorescences (Asteraceae) and characterization of the chemical composition of its secretion.

Rocky outcrop environments at high altitudes have nutrient-poor soil, where species are exposed to water scarcity and high solar radiation. Baccharis platypoda DC. occurs in such an environment and has a rigid and transparent secretion that covers the entire inflorescence. We analysed and compared the secretory structures and their chemical composition in female and male inflorescences of B. platypoda, a dioecious species, to explore chemodiversity within this species and assess potential differences between individuals. Our investigation also aims to understand the occurrence of these substances in the genus Baccharis L. Chemical compounds and secretory structures were similar in female and male inflorescences. There are glandular trichomes on the epidermis of the abaxial surface of bracts, and secretory ducts in the axis of the inflorescence, as well as in sepals, petals, and bracts. Histochemical tests were positive for phenolic compounds, flavonoids, proteins, pectin, and lipids, but not for mucilage. Flavonoid content varied between 6.24% and 9.81%, being higher in female inflorescences. Chromatography revealed the presence of several phenolic compounds, some terpenes, and other less frequent classes in both female and male inflorescences. We highlight that trichomes found on these surfaces produce abundant phenolic compounds. These act as natural defence agents, absorbing UV radiation and minimizing oxidative stress to plant cells. The chemical composition of the secretion covering the inflorescences may reflect adaptation and survival mechanisms of these organisms under extreme sun exposure.

Synergistic electrochemical and optical properties of a UVC class quaternary nanocomposite incorporating graphene oxide and samarium chromium oxide perovskite

This research presents a comprehensive investigation into a novel quaternary nanocomposite comprising graphene oxide (GO), samarium chromium oxide perovskite (SmCrO3), silicon dioxide (SiO2), and tin dioxide (SnO2). The nanocomposite was synthesized using a modified Stöber method. In order to assess its potential applications in supercapacitors and UVC devices, an extensive analysis of its electrochemical and optical properties was conducted. The crystal structure and phase identification were analyzed using X-ray diffraction (XRD) and Rietveld refinement with X'pert HighScore Plus software, confirming the successful formation of the nanocomposite. Scanning electron microscopy (SEM) provided valuable insights into the structural morphology, while energy dispersive X-ray spectroscopy (EDS) confirmed the presence of constituent elements. Fourier transform infrared (FTIR) analysis and Raman Spectroscopy elucidated the functional groups and chemical bonds, confirming the successful synthesis of the nanocomposite. UV–Vis spectroscopy and photoluminescence (PL) spectroscopy revealed its strong UV radiation absorption and intensified fluorescence properties and confirming the band gap of SmCrO3 and GO/SmCrO3/SiO2/SnO2 quaternary nanocomposite as ∼5.4 eV and 4.84 eV respectively. The potential of nanocomposite potential as a supercapacitor material was evaluated through cyclic voltammetry (CV) measurements and electrochemical impedance spectroscopy (EIS) analyses. Remarkably, the specific capacitance of the nanocomposite reached 253.75 Fg−1 at a scan rate of 10 mVs−1, and electrochemical surface area of 507 cm2, highlighting its exceptional charge storage capability and promising prospects for high-performance energy storage devices. This comprehensive study addresses a significant knowledge gap, providing a profound understanding of the electrochemical and optical behavior of the quaternary nanocomposite. The observed exceptional results underscore its suitability for supercapacitor applications and expected favorable material for UVC device technologies.

Natural weathering degradation studies of the poly (3-hydroxybutyrate-co-3 hydroxyvalerate) (PHBV)/paddy straw powder (PSP) biocomposites

The effect of natural weathering exposure time on the poly (3-hydroxybutyrate-co-3 hydroxyvalerate) (PHBV)/paddy straw powder (PSP) biocomposites was studied. These biocomposites were naturally exposed to tropical climate weathering conditions in Perlis, Malaysia for 6 months. Tensile test, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) were applied to investigate the degradation that happened during natural weathering of the biocomposites. Tensile tests indicated that the weathered PHBV/PSP biocomposites caused lower ultimate strength and elongation to break, but increased the modulus of elasticity. As the exposure time prolonged to 6 months, the concentration of O-H groups became pronounced, indicating severe deterioration of the biocomposites. With a carbonyl chromophoric group in its structure, PHBV can absorb UV radiation directly, which could lead to reactions of Norrish forms I and II. Generally, the addition of PSP has increased the degradability of PHBV. Besides, the exposed PHBV/PSP biocomposite surfaces have undergone surface crazing upon weathering. The surface of the PHBV without the addition of the PSP did not show any crack and fungus colonisation. The higher PSP content loaded in the biocomposites (i.e. 20 wt. %) caused more fungi colonisation, resulting in larger cracks and pores formed on the surface of the samples.

Enhanced UV protection in silk fibroin based electrospun fabrics realized via orientation induced high efficiency of azobenzene isomerization

Due to the poor UV protection capability, natural silk fabrics not only suffer from easy damage by sunshine but also induce possible sunburn in the human body. Efficient azobenzene isomerization and enhanced UV shielding are realized by replacing the natural silk with natural protein silk fibroin (SF) and electrospinning together with light-responsive copolymer P(MEO2-co-OEG300-co-AHMA). Compared to a solution cast film, the absorption peak intensity at 355 nm is 60 % higher in UV–Vis spectra of the electropsun SF/P(MEO2-co-OEG300-co-AHMA) fabrics. This improvement is related to the highly oriented chains, inducing more space and higher efficiency for azobenzene isomerization. Only exposure to visible light for 20 min, the absorption peak corresponding to the trans- state at 355 nm recovers to 92.5 % in the electrospun fabrics, which is at least 100 % faster than that in the solution cast film (50 min). It is related to the zip effect of the isomerization in the oriented chain structure. Thus, not only the absorption of UV radiation, but also the isomerization rate is enhanced. Based on these unique absorption and recovery capabilities, the SF based electrospun fabrics can be used to replace the natural silk fabrics for UV shielding in summer, especially for cyclic use.

Aktivitas Tabir Surya Secara In-Vitro Ekstrak dan Fraksi Daun Kedondong (Spondias dulcis Sol. Ex G.Forst)

Excessive sun exposure to the skin can cause redness (erythema) and darkening of the skin (pigmentation). This effect can be prevented by using sunscreen. Kedondong leaves (Spondias dulcis Sol. Ex G. Forst) can act as a natural sunscreen because they contain secondary metabolite compounds with a conjugated double bond structure (chromophore), including phenolic and flavonoid compounds. The presence of conjugated double bonds in phenolic and flavonoid compounds is known to be able to absorb UV radiation thereby reducing its intensity on the skin. This study aims to determine the sunscreen activity of kedondong leaves based on the Sun Protection Factor (SPF), , the percentage of erythema transmission value (%Te), and the percentage of pigmentation transmission value (%Tp) and determine the secondary metabolite groups in kedondong leaf extracts and fractions. The research stages carried out were extraction of kedondong leaves by maceration, dechlorophyllation, followed by fractionation using n-hexane and dichloromethane, to obtain methanol extract, n-hexane fraction, dichloromethane fraction and methanol fraction. Then phytochemical tests were carried out on the extracts and fractions. Phytochemical tests showed that the secondary metabolite compounds in the methanol extract of kedondong leaves were alkaloids, phenolics, steroids and saponins. Furthermore, in the n-hexane fraction are steroids, the dichloromethane fraction is phenolic compounds, and the methanol fraction is alkaloid, phenolic and saponin compounds. Using a UV-Vis spectrophotometer at a wavelength of 200-400 nm, the sunscreen activity test showed that the dichloromethane fraction at a concentration of 120 mg/L was included in the extra protection category with an SPF value of 7,86±0,23; fast tanning with a %Te value of 15,99±0,83 and sunblock with a %Tp value of 32,72±1,09.

In vitro blastocyst implantation and trophoblast migration are disrupted by the UV filter benzophenone-3 (BP3)

Benzophenone-3 (BP3) is a common ingredient in personal care products (PCPs) due to its well-established effectiveness in absorbing UV radiation. Sunscreen products are among the most widely used PCPs-containing BP3 applied to the skin, resulting in significant human exposure to BP3 primarily through a dermal application. In the present work, we have tested the action of three environmentally relevant concentrations of BP3 (2, 20 and 200 μg/L) on an in vitro model of implantation of murine blastocysts and on migration ability of the human trophoblast cell line Swan 71. We showed that BP3 caused a significant reduction of blastocyst expansion and a delayed hatching in a non-monotonic way. Besides, embryos displayed a delayed attachment in the three BP3 groups, resulting in a smaller implantation area on the 6th day of culture: BP3(2) (0.32 ± 0.07 mm2); BP3(20) (0.30 ± 0.08 mm2) and BP3(200) (0.25 ± 0.06 mm2) in comparison to the control (0.42 ± 0.07 mm2). We also found a reduced migration capacity of the human first-trimester trophoblast cell line Swan 71 in a scratch assay when exposed to BP3: the lowest dose displayed a higher uncovered area (UA) at 6h when compared to the control, whereas a higher UA of the wound was observed for the three BP3 concentrations at 18 and 24 h of exposure. The changes in UA provoked by BP3 restored to normal values in the presence of flutamide, an androgen receptor (AR) inhibitor. These results indicate that a direct impairment on early embryo implantation and a defective migration of extravillous trophoblast cells through the androgen receptor pathway can be postulated as mechanisms of BP3-action on early gestation with potential impact on fetal growth.

Science with a Small Two-Band UV-Photometry Mission II: Observations of Stars and Stellar Systems

AbstractWe outline the impact of a small two-band UV-photometry satellite mission on the field of stellar physics, magnetospheres of stars, binaries, stellar clusters, interstellar matter, and exoplanets. On specific examples of different types of stars and stellar systems, we discuss particular requirements for such a satellite mission in terms of specific mission parameters such as bandpass, precision, cadence, and mission duration. We show that such a mission may provide crucial data not only for hot stars that emit most of their light in UV, but also for cool stars, where UV traces their activity. This is important, for instance, for exoplanetary studies, because the level of stellar activity influences habitability. While the main asset of the two-band UV mission rests in time-domain astronomy, an example of open clusters proves that such a mission would be important also for the study of stellar populations. Properties of the interstellar dust are best explored when combining optical and IR information with observations in UV.It is well known that dust absorbs UV radiation efficiently. Consequently, we outline how such a UV mission can be used to detect eclipses of sufficiently hot stars by various dusty objects and study disks, rings, clouds, disintegrating exoplanets or exoasteroids. Furthermore, UV radiation can be used to study the cooling of neutron stars providing information about the extreme states of matter in the interiors of neutron stars and used for mapping heated spots on their surfaces.

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.

Colour and surface functional properties of wool fabrics coated with gallnut, feijoa skin, and mango seed kernel tannin-stabilised Ag nanoparticles.

In the textile industry, textile materials are dyed and multi-functionalised by multi-step treatments that considerably increase the environmental impacts by increasing water and energy usage along with increasing the generation of volume of effluent. In this work, Ag nanoparticles (Ag NPs) were in situ formed and stabilised with gallnut, feijoa fruit skin, and mango seed kernel-derived tannins, and wool fabrics were coated simultaneously with these Ag NPs in the same bath. The Ag NP treatment produced dark to light olive-brown shades on wool fabrics. The treatment conditions for the treatment with Ag NPs were optimised to achieve the best results. The colour intensity, UV radiation absorption, antibacterial activity, surface electrical resistance, and durability of the treatment to washing were assessed by various methods. The gallnut-derived tannin (GNT)-stabilised Ag NP-coated wool fabrics showed overall the best results including excellent antibacterial activity against various types of bacteria. The treatment was durable to at least 20 cycles of IWS 7A washes (equivalent to 80 domestic washes). For the 0.5% Ag NPs on the weight of fibre (owf) dosage, the UV light transmission through the trisodium citrate-stabilised Ag NP-coated fabric at 365 and 311 nm was 6.37 and 0.95% respectively, which reduced to 1.63 and 0.20% for the fabric coated with GNT-stabilised Ag NPs providing excellent protection against UV radiation. The surface resistivity of wool fabric reduced from 1.1 × 1012 ohm cm-1 for the untreated fabric to 1.1 × 109 ohm cm-1 for the fabric coated with 2.0% owf GNT-stabilised Ag NPs. The stabilisation of Ag NPs with GNT prolonged the wash-durability by reducing the leaching of Ag NPs from the treated fabric. The developed method could be a sustainable alternative to traditional multi-stage treatments conducted in the textile industry with toxic synthetic dyes and finishing agents for the colouration and multifunctionalisation of wool fabrics.

ACTIVITY TEST OF BRACTEA BOUGAINVILLEA SPECTABILIS WILLD SOLAR SCREEN CREAM EXTRACT IN WAY IN VITRO AND IN VIVO

Excessive radiation exposure to the skin can cause erythema and pigmentation on the skin. Bougainvillea spectabilis Willd\'s ethanol extract contains bioactive compounds that have medicinal properties, such as phenolic compounds and flavonoids which have conjugated double bonds which are able to specifically absorb UV radiation so they can be applied chemical absorber. This study aims to test the sunscreen activity of the ethanol extract of Bougainvillea spectabilis Willd bractea in vitro using the UV-Visible spectrophotometric method which is determined by calculating the % Transmission value of erythema (% Te), the value of % Transmission pigmentation (% Tp), and the value Sun Protection Factor (SPF). As well as regular testing alive by observing the effect of erythema on the skin of white mice (Rattus norvegicus) which is irradiated with UV light. Analysis results in vitro showed that Willd\'s Bougainvillea spectabilis ethanol extract cream was able to provide sunscreen activity with concentrations of 1.5%, 1.0%, 0.5% with SPF values respectively 21.22 (ultra protection); 16.69 (ultra protection) and 12.48 (maximum protection) compared to the Para amino benzoic acid (PABA) control 6.95 (extra protection), with a percent erythema (% Te) concentration value of 1.5%, 1.0% , 0.5% with consecutive values of 6.85 (standard suntan); 7.26 (standard suntan) and 10.42 (fast tanning) compared to control cream Para amino benzoic acid (PABA) 28.15 (fast tanning), with a percent pigmentation value (% Tp) concentration of 1.5%, 1.0 %, 0.5% with consecutive values of 7.29 (sunblock); 7.56 (sunblock) and 11.62 (sunblock) compared to the Para amino benzoic acid (PABA) control, namely 60.10 (extra protection). Then on to testing alive using one-way ANOVA analysis, it was found that Bougainvillea spectabilis Willd bractea ethanol extract was able to inhibit the emergence of erythema in test animals significantly (p<0.05) in all treatment groups, with the diameter of erythema formed at concentrations of 1.5%, 1.0% , 0.5% produces an erythema score of 1, which means very little erythema is produced.