In situ Raman characterization of the stability of blueberry anthocyanins in aqueous solutions under perturbations in temperature, UV, pH.

Blueberry anthocyanin (BA) is a functional ingredient to enhance the biological activity of food, and the stability of BA is of great interest. BA stability in aqueous solutions stored in polypropylene and glass bottles was analyzed in-situ using confocal Raman spectroscopy, and the acceptable depth of focus was optimized. The Raman characteristics of BA degradation were explained by multivariate analysis. The degradation rate of BA was significantly accelerated by heating above 65 °C for 2 h or ultraviolet irradiation (10 W) for 96 h. The first order kinetic reaction rate was accelerated with the increase of pH value and temperature and the prolongation of ultraviolet irradiation time. The synergistic effect of multiple factors promoted BA degradation. This study provides an in-situ, nondestructive method for the analysis of anthocyanin stability, which has great utility in the food industry to optimize processing, storage, and transportation measures to reduce the degradation of BA.

Isolation and structural determination of cis- and trans-p-coumaroyl-secologanoside (comselogoside) from olive oil waste (alperujo). Photoisomerization with ultraviolet irradiation and antioxidant activities.

p-Coumaroyl-6́-secologanoside (comselogoside) is a secoiridoid identified in large amounts in olive fruits, although no studies in vitro or in vivo of comselogoside have been reported. This work focuses on the recovery and purification of this compound from olive mill waste (alperujo). The successive isolation on Amberlite XAD-16 and Sephadex LH-20 resins, allowed a comselogoside extract with 80-85% of purity. A photoisomerization of the vinyl-double bond in the p-coumaroyl moiety occurred when the extract was exposed to ultraviolet radiation and a mixture of the trans and cis-isomers was obtained. Both isomers were characterized using NMR, mass spectroscopy, and UV spectrometry. The J (coupling constant) of the protons on the C7 and C8 on the unsaturated chain were found to be the difference between cis (12.8 Hz) and trans- (15.9 Hz) comselogoside. Cis-isomer exhibited lower radical-scavenging activity than trans, although a synergistic effect occurred when the cis-isomer was supplement by the trans-isomer.

[Research Progress on Distribution Characteristics and Formation Mechanisms of Microplastics in the Environment].

The extensive application of plastic products leads to the increasingly significant harm of plastic wastes to the ecological environment, which is also a focus of global environmental issues. Due to the lack of a sound plastic waste management system, most plastic waste is still treated by the traditional mode or remains in the environment, with low recycling efficiency, and the plastic life cycle has not yet formed. Plastics in the environment will age and degrade under the actions of physical (wear, waves), chemical (ultraviolet radiation, hydrolysis), and biological (fungi, bacteria) factors for a long time and generate micro (nano) plastics. Due to their small particle size, large specific surface area, and charged characteristics, in addition to their own toxicity, they can also be used as carriers or covert carriers of pollutants (heavy metals, persistent organic pollutants, polycyclic aromatic hydrocarbons, bacteria, etc.) to migrate in the environment through runoff, sewage discharge, and hydrometeorology, causing ecological environmental pollution. MPs pollution has been listed as the second largest scientific problem in the field of environmental and ecological science by the United Nations Environment Programme. MPs are widely distributed, and there are different degrees of MPs pollution in the global water (freshwater, ocean), soil, and atmospheric environment. Traces of MPs have also been found in human placentas, human breastmilk, living lungs, and blood in recent years. Therefore, the formation mechanisms of MPs under the actions of physics, chemistry, and microorganisms, as well as their abundance levels and migration characteristics in water, soil, and atmosphere environment were comprehensively reviewed, with the hope of providing reference for monitoring the pollution levels of MPs in the environment, exploring their transport laws in the environment, proposing the management strategy of MPs pollution, and revealing the degradation mechanisms of MPs under different effects.

An overview on the use of ultraviolet radiation to disinfect air and surfaces.

Background and aim Ultraviolet radiation (UV) is the portion of the electromagnetic spectrum of wavelengths between 200 and 400 nm divided into three bands called UVA, UVB and UVC. Due its well-described antimicrobial activity, UVC can represent a useful tool for disinfect surfaces, water, and air. The aim of this study was to illustrate the studies over time ultraviolet germicidal irradiation (UVGI) to disinfect air and surfaces. Methods Articles on Scopus published until April 14, 2023, were considered. Many issues involving UV were deepened crosschecking with e.g., "air", "surfaces", "disinfection", "bacteria", "fungi", "operating theatres". According to the case, the following variables were considered: years and related number of articles, sources of publications, subject areas, type of document published, type of journal, nationalities of the authors. Results Since 30's, 287 448 articles on UV have been published. Among UVGI, 22 159 articles covered bacteria issue, followed by fungi and viruses with about 12000 both. UVGI was addressed by 1941 and 931 articles for surfaces and air respectively. Of these, 122 were performed in operating theatres. Since 1987 works have been published on spacecraft and since 2000, on the use of UVGI robots for disinfect air and surfaces. Conclusions Our study shows the studies on UVGI and related issues. It also shows most recently perspectives about the applications e.g. during prolonged human-crewed missions on spacecrafts, to inactivate microorganisms in environments where the exchange of air is impossible.

Tetrahydrobiopterin as a Trigger for Vitiligo: Phototransformation during UV Irradiation.

Vitiligo is a type of hypomelanosis. Tetrahydrobiopterin (H4Bip), the coenzyme of the initial stage of melanogenesis, appears to be a trigger for vitiligo. H4Bip is present in vitiligo in 3-5-fold excess and causes oxidative stress by triggering an autocatalytic cycle of excess hydrogen peroxide synthesis. Using quantum-chemical calculations, we have evaluated the possibility of H4Bip reactions occurring in the dark and under ultraviolet (UV) irradiation, including the formation of dihydropterin dimers. In order to simulate the oxidative stress, oxidative modification of human serum albumin (HSA) has been carried out in the presence of excessive H4Bip using the fluorescence method. The fraction of oxidized protein (FOP) has been calculated. It has been established that there is a strong oxidative modification of amino acids chromophores (tryptophan and tyrosine) in the protein (FOP 0.64). Under UV irradiation of the system (HSA + H4Bip), FOP is reduced to 0.39. Apparently, a part of H4Bip transforms into dihydropterin dimers and does not participate in the oxidative modification of the protein. The data on oxidative modification of HSA are consistent with dynamic light scattering: H4Bip promotes HSA aggregation with the formation of particles with a hydrodynamic radius Rh ≥ 2000 nm, which can become immunogenic.

Antioxidant and photoprotective role of latex C-serum from Hevea brasiliensis during 15-week UVB irradiation in male hairless SKH-1 mice.

It is known that UVB radiation induces several adverse skin alterations starting from simple photoaging to skin cancer. In addition, it was demonstrated that reactive oxygen species (ROS) were found to be related to cancer development and progression. The aim of study was to examine whether male hairless (SKH-1) mice (Mus musculus) that were subchronically exposed to UVB radiation presented with actinic keratosis (AK) and squamous cell carcinoma lesions, and that treatment with latex C-serum cream significantly prevented abnormal skin development. Data demonstrated for the first time the photoprotective activity of latex C-serum extracted from the rubber tree Hevea brasiliensis var. subconcolor Ducke. Latex C-serum prevented the progression of AK to squamous cell carcinoma in SKH-1 mice, indicating that mice topically treated with latex C-serum presented only AK lesions and treatment with the highest concentration (10%) significantly reduced epidermal thickness, suggesting diminished cell proliferation. Latex C-serum protected the skin of mice against oxidative stress damage, increasing catalase (CAT) activity, regenerating glutathione (GSH) levels, lowering thiobarbituric acid-reactive species (TBARS) production and regenerating the total antioxidant capacity (TAC) of the skin. Evidence that UV radiation in skin induced systemic alterations and erythrocytic analysis indicated that latex C-serum increased CAT activity and GSH levels. Taken together these data indicate that latex C-serum plays an important antioxidant and photoprotective role, preventing serious damage to the skin following exposure to UVB radiation.

The efficiency of UV light-emitting diodes (UV-LED) in decontaminating Campylobacter and Salmonella and natural microbiota in chicken breast, compared to a UV pilot-plant scale device.

This study investigated the combined effect of Ultraviolet (UV) light-emitting diode (LED) technology treatment with refrigerated storage of chicken breast meat over 7 days on Campylobacter jejuni, Salmonella enterica serovar Typhimurium, total viable counts (TVC) and total Enterobacteriaceae counts (TEC). An optimised UV-LED treatment at 280 nm for 6 min decreased inoculated S. Typhimurium and C. jejuni populations by 0.6-0.64 log CFU/g, and TVC and TEC population by 1-1.2 log CFU/g in chicken samples. During a 7-day storage at 4 °C, a 0.73 log reduction in C. jejuni was achieved compared with non-treated samples. Moreover, the UV-LED effectiveness to reduce TVC and TEC during refrigerated storage was compared with a conventional UV lamp and a similar efficiency was observed. The impact of UV-LED and UV lamp devices on the microbial community composition of chicken meat during storage was further examined using 16 S rRNA gene amplicon sequencing. Although similar bacterial reductions were observed for both technologies, the microbial communities were impacted differently. Treatment with the UV conventional lamp increased the proportion of Brochothrix spp. In meat samples, whilst Photobacterium spp. Levels were reduced.

Ecology and resistance to UV light and antibiotics of microbial communities on UV cabins in the dermatology service of a Spanish hospital.

Microorganisms colonize all possible ecological habitats, including those subjected to harsh stressors such as UV radiation. Hospitals, in particular the UV cabins used in phototherapy units, constitute an environment in which microbes are intermittently subjected to UV irradiation. This selective pressure, in addition to the frequent use of antibiotics by patients, may represent a threat in the context of the increasing problem of antimicrobial resistance. In this work, a collection of microorganisms has been established in order to study the microbiota associated to the inner and outer surfaces of UV cabins and to assess their resistance to UV light and the antibiotics frequently used in the Dermatology Service of a Spanish hospital. Our results show that UV cabins harbor a relatively diverse biocenosis dominated by typically UV-resistant microorganisms commonly found in sun-irradiated environments, such as Kocuria, Micrococcus or Deinococcus spp., but also clinically relevant taxa, such as Staphylococcus or Pseudomonas spp. The UV-radiation assays revealed that, although some isolates displayed some resistance, UV is not a major factor shaping the biocenosis living on the cabins, since a similar pool of resistant microorganisms was identified on the external surface of the cabins. Interestingly, some Staphylococcus spp. displayed resistance to one or more antibiotics, although the hospital reported no cases of antibiotic-resistance infections of the patients using the cabins. Finally, no association between UV and antibiotic resistances was found.

Effects of UV and Calcium Perchlorates on Uracil Deposited on Strontium Fluoride Substrates at Mars Pressure and Temperature.

Organic matter is actively searched on Mars with current and future space missions as it is a key to detecting potential biosignatures. Given the current harsh environmental conditions at the surface of Mars, many organic compounds might not be preserved over a long period as they are exposed to energetic radiation such as ultraviolet light, which is not filtered above 190 nm by the martian atmosphere. Moreover, the presence of strong oxidizing species in the regolith, such as perchlorate salts, might enhance the photodegradation of organic compounds of astrobiological interest. Because current space instruments analyze samples collected in the upper surface layer, it is necessary to investigate the stability of organic matter at the surface of Mars. Previous experimental studies have shown that uracil, a molecule relevant to astrobiology, is quickly photolyzed when exposed to UV radiation under the temperature and pressure conditions of the martian surface with an experimental quantum efficiency of photodecomposition (φexp) of 0.30 ± 0.26 molecule·photon-1. Moreover, the photolysis of uracil leads to the formation of more stable photoproducts that were identified as uracil dimers. The present work aims to characterize the additional effect of calcium perchlorate detected on Mars on the degradation of uracil. Results show that the presence of calcium perchlorate enhances the photodecomposition of uracil with φexp = 12.3 ± 8.3 molecule·photon-1. Although some of the photoproducts formed during these experiments are common to those formed from pure uracil only, the Fourier transformation infrared (FTIR) detection of previously unseen chemical functions such as alkyne C ≡ C or nitrile C ≡ N has shown that additional chemical species are formed in the presence of calcium perchlorate in the irradiated sample. This implies that the effect of calcium perchlorate on the photolysis of uracil is not only kinetic but also related to the nature of the photoproducts formed.

Defect-poor BaSn(OH)6 enhanced charge separation for efficient photocatalytic degradation of toluene.

Crystal defect is well-known to have a significant effect on the photocatalytic performance of semiconductors. Herein, defect-rich and -poor BaSn(OH)6 (BSOH-Sn and BSOH-Ba) photocatalysts were synthesized by exchanging the addition order of Ba and Sn. Results show that the defect-poor BSOH-Ba exhibited more efficient toluene degradation under ultraviolet (UV) light, which could attribute to the great suppression of photogenerated electron-hole (e--h+) pairs recombination by tuning the defect concentration. The low defect concentration in BSOH-Ba finally promotes the charge separation efficiency, the generation of reactive oxygen species (ROS), and the photocatalytic toluene degradation reactions. This work not only provides an effective way to inhibit the recombination of photogenerated carriers and improve the photocatalytic performance, but also promotes the understanding of defective perovskite-type hydroxide for more photoreactions.

Diffusion Depth and Efficacy of Different Infiltration Times for Rose Bengal/Green Light Corneal Cross-linking in Rabbit Eyes.

PURPOSE: To explore the diffusion depth and green light corneal cross-linking efficacy of different rose bengal (Rb) infiltration times in rabbit eyes. METHODS: Twenty-eight fresh rabbit eyes were deepithelialized and infiltrated in 0.1% Rb solution for 2 to 30 minutes. Corneal frozen sections were cut and Rb diffusion depth was observed under the confocal microscope. A further 36 rabbits were randomly divided into eight groups according to the type of treatment (control, Rb infiltration only without irradiation, rose bengal/green light [RGX] for different infiltration times, or riboflavin/ultraviolet radiation [UVX]). The corneas' resistance to keratolysis and biomechanical properties were measured after treatment. RESULTS: After 2, 10, 20, and 30 minutes of infiltration, Rb penetration depths in the corneal stroma were 100, 150, 200, and 270 µm, respectively. The times for complete digestion of the RGX 10 minutes (14.0 ± 1.4 hours), RGX 20 minutes (18.8 ± 1.1 hours), and UVX (51.2 ± 7.2 hours) groups were statistically greater than that of the control group (7.2 ± 1.1 hours). At 10% extension, the Young's modulus of the RGX 20 minutes (36.59 ± 4.90 MPa) and UVX (40.89 ± 2.57 MPa) groups was statistically greater than that of the control group (21.76 ± 5.69 MPa). CONCLUSIONS: The diffusion depth of Rb in corneal stroma increased by prolonging the infiltration time. The longer the infiltration time, the better the RGX effect. RGX for 20 minutes showed the best cross-linking efficacy among all RGX groups, albeit not as good as UVX. [J Refract Surg. 2023;39(9):620-626.].

Broad-spectrum sunscreens containing the TriAsorB™ filter: In vitro photoprotection and clinical evaluation of blue light-induced skin pigmentation.

BACKGROUND: Blue light (BL), particularly high-energy visible (HEV) light (400-450 nm), can cause skin damage and pigmentation. Therefore, effective sunscreens should offer photoprotection beyond ultraviolet (UV) radiation to also prevent or limit BL-induced cutaneous effects. OBJECTIVES: To evaluate the in vitro BL photostability and photoprotection properties of nine sunscreens containing the broad-spectrum UV/BL phenylene bis-diphenyltriazine (PBDT or TriAsorB™) filter, together with three other organic UV filters, and to assess the in vivo photoprotection level provided by two of these products against BL-induced skin pigmentation. METHODS: In vitro BL photostability and photoprotection factors, comprising the percentage of BL radiation stopped by the product (%BL) and the critical wavelength extended to BL (BL-CW), were determined by spectrophotometry. The in vivo photoprotection provided by two representative sunscreens (i.e. similar formulations, one non-tinted and one tinted) was assessed in two open randomized studies (20 and 16 women, respectively) after exposure of two test areas (with and without sunscreen) on the back of each subject to a 412-nm irradiation dose at 50 J/cm2 , using instrumental and clinical measurements of skin pigmentation. The percentage sunscreen photoprotective effectiveness (%PPE) was calculated by comparing intrasubject post-exposure pigmentation changes between the with and without sunscreen test areas. RESULTS: In vitro, the nine PBDT-containing products were highly photostable and had a BL-CW ≥385 nm and a %BL ≥30% (range: 30%-50%), thus allowing effective BL photoprotection. In vivo, both representative sunscreens prevented BL-induced immediate skin pigmentation (1 and 24 h post-exposure) with %PPE values ranging from 50.7% to 75.5% for colorimetric assessments (p < 0.001) and from 31.2% to 72.7% for visual scores (p ≤ 0.001). CONCLUSIONS: All PBDT-containing sunscreens were considered effective at absorbing BL radiation in vitro. The two representative broad-spectrum sunscreens tested in subjects significantly reduced BL-induced immediate skin pigmentation following single exposure to monochromatic BL radiation.

In vivo method for evaluating sunscreen protection against high-energy visible light.

BACKGROUND: Overexposure to sunlight can have many harmful biological effects on the skin, leading to skin cancer and photoaging. As ultraviolet (UV) radiation has been identified as a cause of DNA damage and oxidative stress in the skin, the photoprotection provided by sunscreens is evaluated through their ability to filter UV light, using the sun protection factor (SPF). However, recent data have shown that high-energy visible (HEV) light can also cause biological skin damage. OBJECTIVES: To develop a new in vivo method for evaluating the protection provided by sunscreens across a broad range of wavelengths, including the HEV band, based on multispectral image analysis. METHODS: This study evaluated the absorption properties of six commercially available sunscreens (five SPF 50+ products containing organic UV filters, and one product containing the wide spectrum filter, phenylene bis-diphenyltriazine [TriAsorB™]) and of a control product containing no filter. Multispectral images were acquired from the skin on the forearms of healthy volunteers, before and after application of the test products. Images taken with LEDs emitting light at wavelengths ranging from UV to infrared were used to generate light reflectance maps for each product. The levels of absorbance of light in the UV and visible bands were then calculated. RESULTS: The product containing the wide spectrum filter exhibited significantly higher absorbance over the HEV band (380-450 nm) than the control product and the other commercial sunscreens. All the sunscreens tested showed the same level of absorbance at 365 nm (UVA). CONCLUSIONS: Multispectral imaging provides a simple and reliable in vivo method for assessing the real-world protection provided by sunscreens against all forms of photo-induced skin damage, including that induced by HEV radiation.

Somatic mutations in facial skin from countries of contrasting skin cancer risk.

The incidence of keratinocyte cancer (basal cell and squamous cell carcinomas of the skin) is 17-fold lower in Singapore than the UK1-3, despite Singapore receiving 2-3 times more ultraviolet (UV) radiation4,5. Aging skin contains somatic mutant clones from which such cancers develop6,7. We hypothesized that differences in keratinocyte cancer incidence may be reflected in the normal skin mutational landscape. Here we show that, compared to Singapore, aging facial skin from populations in the UK has a fourfold greater mutational burden, a predominant UV mutational signature, increased copy number aberrations and increased mutant TP53 selection. These features are shared by keratinocyte cancers from high-incidence and low-incidence populations8-13. In Singaporean skin, most mutations result from cell-intrinsic processes; mutant NOTCH1 and NOTCH2 are more strongly selected than in the UK. Aging skin in a high-incidence country has multiple features convergent with cancer that are not found in a low-risk country. These differences may reflect germline variation in UV-protective genes.

Far-UVC- and UVB-induced DNA damage depending on skin type.

Far-UVC radiation sources of wavelengths 222 nm and 233 nm represent an interesting potential alternative for the antiseptic treatment of the skin due to their high skin compatibility. Nevertheless, no studies on far-UVC-induced DNA damage in different skin types have been published to date, which this study aims for. After irradiating the skin with far-UVC of the wavelengths 222 and 233 nm as well as broadband UVB, the tissue was screened for cyclobutane pyrimidine dimer-positive (CPD+ ) cells using immunohistochemistry. The epidermal DNA damage was lower in dark skin types than in fair skin types after irradiation at 233 nm. Contrary to this, irradiation at 222 nm caused no skin type-dependent differences, which can be attributed to the decreased penetration depth of radiation. UVB showed the relatively strongest differences between light and dark skin types when using a suberythemal dose of 3 mJ/cm2 . As melanin is known for its photoprotective effect, we evaluated the ratio of melanin content in the stratum basale and stratum granulosum in samples of different skin types using two-photon excited fluorescence lifetime imaging (TPE-FLIM) finding a higher ratio up to skin type IV-V. As far-UVC is known to penetrate only into the upper layers of the viable skin, the aforementioned melanin ratio could explain the less pronounced differences between skin types after irradiation with far-UVC compared to UVB.

Degradation of p-cresol in the presence of UV light driven in an integrated system containing photocatalytic and packed bed biofilm reactor.

Integratingphotocatalysisand biodegradation has shown great potential in wastewater treatment technology. In this study, the degradation of p-cresol in water has been investigated through an integrated system comprising of photocatalytic and packed bed biofilm reactor (PBBR). In the photocatalytic reactor, the biodegradability index (BOD5/COD, BOD5/TOC) of the p-cresol solution was first shown to increase (from 0.098±0.023 to 0.59±0.089 for BOD5/COD and from 0.27±0.030 to 1.74±0.03 for BOD5/TOC). The pseudo-first-order rate constant (kap) was found to be 0.011 min-1. The % removal of the integrated system was found to be 98.43±1.31% at an initial concentration of 700 mg L-1 and residence time of 120 h, which was significantly higher than the PBBR operated alone (34.82±2.62%) under optimized conditions (pH 7.0 and T = 32±2 °C). Using an integrated approach, the efficient removal of p-cresol opens novel future perspectives for catalytic degradation using chemical oxidation.

Efficient removal of electroneutral carbonyls by combined vacuum-UV oxidation and anion-exchange resin adsorption: mechanism, model simulation, and optimization.

Electroneutral carbonyls (ENCs) with low molecular weights (e.g., aldehydes and ketones) are recalcitrant to single water treatment process to achieve ultralow concentration. Residual ENCs are present in reverse osmosis permeate and pose risks to human health during potable use or industrial application in manufacturing processes. Herein, a combined vacuum-UV (VUV) oxidation and anion-exchange resin (AER) adsorption method was developed to treat the ENCs and reduce total organic carbon (TOC) to an ultralow concentration (< 5 µg/L) with high efficiency and at low cost. VUV-AER was 2.1-2.4 times more efficient than VUV alone for the removal of TOC. VUV oxidized the ENCs to electronegative carboxylic acids, which were adsorbed by the AER through electrostatic interactions and hydrogen bonding. When the VUV fluence was lower than 643 mJ cm-2, the AER could not achieve ultralow TOC removal of ENCs. The treat capacity of 1500-2900 valid bed volume (BVs) was achieved after increasing the VUV fluence to 1929 mJ cm-2. The AER could more efficiently adsorb carboxylic acids that contained more carboxylic groups or shorter carbon chain. Acetate was identified as the primary breakthrough product at relatively low VUV fluence, and oxalate was the main byproduct at relatively high VUV fluence. A mathematical model to predict TOC breakthrough was developed considering the VUV-oxidation kinetics and the AER breakthrough curve. The model was used to optimize the method to maximize TOC removal and minimize energy consumption. These results imply that VUV-AER is technically feasible and economically applicable to eliminate recalcitrant ENCs to ultralow concentration for the production of water requires high quality (e.g., potable water or electronic-grade ultrapure water).

Luteolin photo-protects zebrafish from environmental stressor ultraviolet radiation (UVB).

Ultraviolet B wavelength ray radiation (UVB) is an environmental stressor with detrimental effects to the aquatic and human systems but also enhances adverse effects when combined with several other environmental factors such as temperature and pollution. UV rays induce cellular oxidative damage and impair motility. This study aimed to examine the photo-protective activity of flavonoid luteolin against UV-B irradiation-induced oxidative stress and cellular damage using zebrafish. An in-vivo photoaging model was established using UV-B irradiation in zebrafish larvae exposed to 100 mJ/cm2. Data demonstrated that UV-B irradiation of swimming water enhanced production of ROS and superoxide anions as well as depleted total glutathione levels in zebrafish larvae. UV-B irradiation also triggered cellular damage and membrane rupture in zebra fish. Further, 100 mJ/cm2 of UV-B radiation exposure to adult-wild type zebrafish co-exposed with intraperitoneally (ip) injected luteolin upregulated the local neuroendocrine axes by activating vascular endothelial growth factor (VEGF) and elevating levels of pro-inflammatory cytokines IL-1ß and TNF-α. Histologically, UV-B irradiation induced skin lesions and locomotory defects with clumping and degeneration of brain glial cells. However, luteolin effectively inhibited the excess production of reactive oxygen species (ROS) and decreased superoxide anion levels induced by UV-B irradiation. Luteolin restored the depleted glutathione levels. In addition, luteolin blocked apoptosis and lipidperoxidation. Luteolin protected adult zebrafish by downregulating the pro-inflammatory cytokine protein expression levels and diminishing VEGF activation. Luteolin also alleviated locomotory defects by inhibiting activation of microglia and inflammatory responses by preventing accumulation of glial cells and vacuolation. Data demonstrate that luteolin may protect zebrafish from UV-B-induced photodamage through DNA-protective, antioxidant and anti-inflammatory responses.

Patterns of Sun Protection Behaviours among Australian Adolescents and Adults over a Six-Year Period.

The major cause for skin cancer is the excessive and unprotected exposure to ultraviolet radiation (UVR), which can be prevented by engaging in sun protection behaviours. As longitudinal studies on both adolescents' and adults' performances of sun protection behaviours are limited, the current study aimed to investigate changes in sun protection in these population segments in Western Australia, a region with high annual UVR. During six summer seasons (2015/16 to 2020/21), cross-sectional surveys were conducted among 1806 adolescents (14 to 17 years old) and 1808 adults (18-45 years old), investigating the frequency of five sun protection behaviours (wearing clothing, applying sunscreen, wearing a hat, wearing sunglasses, and seeking shade) and sun avoidance (staying indoors). Over the six-year period, staying indoors increased in both groups. Among adolescents, a decrease in wearing clothing and sunglasses and an increase in seeking shade was demonstrated, and hat and sunscreen use remained relatively stable. Among adults, an increase in sunscreen use was shown, whereas all other sun-related behaviours remained consistent over the six-year period. The results from this study can provide directions for health communications focusing on improving sun protection behaviours among both adolescent and adult populations.

Oral phytochemicals as photoprotectants in UVR exposed hairless mice: A study of hesperidin methyl chalcone, phloroglucinol, and syringic acid.

Ultraviolet radiation is the primary risk factor for keratinocyte carcinoma. Because of increasing incidence rates, new methods of photoprotection must be explored. Oral supplementation with photoprotective compounds presents a promising alternative. Phytochemical compounds like hesperidin methyl chalcone, phloroglucinol, and syringic acid are particularly of interest because of their antioxidant properties. Our primary outcome was to evaluate the effects of oral phytochemicals on photocarcinogenesis with time until tumour onset as the primary endpoint. A total of 125 hairless C3.Cg-Hrhr/TifBom Tac mice were randomised to receive tap water supplemented with either 100 mg/kg hesperidin methyl chalcone, phloroglucinol, or syringic acid, 600 mg/kg nicotinamide as a positive control, or no supplementation. The mice were irradiated with 3.5 standard erythema doses thrice weekly to induce photocarcinogenesis. Supplementation with the phytochemicals phloroglucinol and syringic acid and nicotinamide delayed tumour onset from a median of 140 days to 151 (p = 0.036), 157 days (p = 0.02), and 178 (p = 2.7·10-5), respectively. Phloroglucinol and nicotinamide supplementation reduced tumour number. Nicotinamide increased UV-induced pigmentation and reduced oedema formation, while phloroglucinol supplementation reduced epidermal thickness. These results indicate that oral supplementation with phloroglucinol and syringic acid protects against photocarcinogenesis in hairless mice, but not to the same extent as nicotinamide.