UVA Irradiation Research Articles

Different patterns of the photosynthetic apparatus recovery during early rehydration following drought stress in two types of intergeneric hybrid of triticale

The study aimed to reveal the activity of the photosynthetic apparatus during early rehydration in double haploid (DH) lines of triticale with different types of flag leaf rolling in response to soil drought. Two DH lines, showing full (Type O) and limited (Type V) flag leaf rolling, were investigated. The measurements of chlorophyll fluorescence, analysis of red/far-red fluorescence excitation spectra, as well as detection of selected PSII proteins (PsbA/D1, PsbS) and transmembrane cytochrome complex b6f (PetC/Rieske protein) were performed. The measurements were carried out on the last day of drought and after 1 h, 3 h, and 5 h of rehydration. The physiological condition of flag leaves was studied based on measurements of water relations, the progress of leaf senescence, histochemical detection of reactive oxygen species, and the content of sugars and phenolic compounds. In Type O, as compared with Type V, a further decline in the activity of the photosynthetic apparatus was observed during the post-drought rehydration period. This was accompanied by the accumulation of reactive oxygen species and more advanced senescence of flag leaves. Fluorescence excitation spectra revealed disorders in photosynthetic light conversion in Type O flag leaves during drought and rehydration over the entire range of excitation wavelengths corresponding to UVC, UVB, and UVA radiation. Type V flag leaves developed an effective UV protection mechanism in the form of increased accumulation of cell wall-bound phenolics, which efficiently absorbed UV radiation. Both types differed in the level of accumulation of PsbA, PsbS, and PetC proteins during drought and early rehydration. Soil drought caused a similar reduction in grain yield in both types. However, in Type O, the largest share in the grain yield was ascribed to the ears of lateral stems, while in Type V to the ears of the main stems. Our research has shown that the limited rolling of flag leaves under drought stress corresponds to the effective photoprotection of the photosynthetic apparatus in the first hours of rehydration.

Immobilization of ZnO:Ga nanocrystals in a polystyrene/cellulose matrix: A novel hybrid nanocomposite photocatalyst for future photo energy application

This article reports a portable, flexible gallium doped zinc oxide/polystyrene/cellulose (GZO/PSC) nanocomposite and the development of a hybrid material for various applications primarily in water treatment and renewable energy. With respect to a green technology, our nanocomposite can be easily eliminated from the pollution mixture, after using. A complete morphological, structural, mechanical, chemical, and optical characterization was made using different analysis techniques. Secondly, catalytic activities for photocatalytic and sonocatalytic degradation were evaluated by decolorizing methylene blue/orange in an aqueous solution under dark, light, and ultrasonic exposure. The synthesized GZO NPs and GZO/PSC hybrid nanocomposite showed a high decolorization efficiency in a short time. These samples destroyed the MB dye molecule (98 and 96 ± 1%) in just 10 and 45 min respectively, under UVA irradiation. Just 7 min simultaneous irradiation of both UVA light/ultrasonic resulted in 95% destruction of MB molecules for GZO NPs (neat fillers). Our results show that the GZO/PS and GZO/PSC hybrid films (Ga:ZnO@PCS) can be easily used in both the field of flexible luminescent devices and water treatment, respectively. At the same time, no photocatalyst remained in the reaction system after wastewater treatment. This simple approach can be upscaled for industrial use.

The role of noble metals in TiO2 nanotubes for the abatement of parabens by photocatalysis, catalytic and photocatalytic ozonation

The role of modified TiO2 nanotubes (TNTs) with noble metals was studied for photocatalysis, catalytic and photocatalytic ozonation of a paraben’s mixture. The TNTs were obtained by anodization and were modified by photodeposition with 0.25 mol% of Au, Pt or Pd.Results showed that solar photocatalysis led to higher degradation than UVA radiation, and under UVA radiation, the use of 3 Pt-TNTs (3 TNTs plates modified with Pt) and 3 Pd-TNTs present the same effect as the use of 5 and 7 pristine-TNTs plates, respectively. The best parabens removal was achieved for Pd-TNTs under UVA radiation and pristine TNTs under solar radiation, with 43% and 81% removal in 120 min, respectively.All the catalytic and photocatalytic ozonation experiments led to less ozone consumption than single ozonation (transferred ozone dose (TOD) = 5.27 mgO3/L) with total parabens abatement. Catalytic ozonation experiments suggest that the presence of metals can promote the formation of oxidative radicals, with the Au-TNTs presenting best performance (TOD ≈ 3.59 mgO3/L) while pristine TNTs led to TOD = 4.98 mgO3/L. For photocatalytic ozonation, the pristine TNTs led to the lowest ozone consumption (TOD = 3.74 mgO3/L).Moreover, the use of hydroxyl radical scavenger showed that hydroxyl radical is formed during single and photocatalytic ozonation mechanism, which should be related to the natural and surface catalytic ozone decomposition.

Sesamin attenuates UVA-induced keratinocyte injury via inhibiting ASK-1-JNK/p38 MAPK pathways.

Ultraviolet (UV) exposure-stimulated reactive oxygen species (ROS) formation in keratinocytes is a crucial factor in skin aging. Phytochemicals have become widely popular for protecting the skin from UV-induced cell injury. Sesamin (SSM) has been shown to play a role in extensive pharmacological activity and exhibit photoprotective effects. To assess the protective effect of SSM on UVA-irradiated keratinocytes and determine its potential antiphotoaging effect. HaCaT keratinocytes pretreated with SSM were exposed to UVA radiation at 8 J/cm2 for 10 min. Cell viability and oxidative stress indicators were evaluated using a cell counting kit-8 and lactate dehydrogenase (LDH), malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) assay kits. Apoptosis and intracellular ROS levels were analyzed using annexin V-fluorescein isothiocyanate/propyridine iodide and dichlorodihydrofluorescein diacetate staining, respectively. Protein levels of matrix metalloprotein-1 (MMP-1), MMP-9, Bax/Bcl-2, and mitogen-activated protein kinase (MAPK) pathway proteins, phospho-apoptosis signal-regulating kinase-1 (p-ASK-1)/ASK-1, phospho-c-Jun N-terminal protein kinase (p-JNK)/JNK, and p-p38/p38 were determined using western blotting. Sesamin showed no cytotoxicity until 160 μmol/L on human keratinocytes. Sesamin pretreatment (20 and 40 μM) reversed the suppressed cell viability, increased LDH release and MDA content, decreased cellular antioxidants GSH and SOD, and elevated intracellular ROS levels, which were induced by UVA irradiation. Additionally, SSM inhibited the expression of Bax, MMP-1, and MMP-9 and stimulated Bcl-2 expression. In terms of the regulatory mechanisms, we demonstrated that SSM inhibits the phosphorylation of ASK-1, JNK, and p38. The results suggest that SSM attenuates UVA-induced keratinocyte injury by inhibiting the ASK-1-JNK/p38 MAPK pathways.

Cannabidiol and Cannabigerol Modify the Composition and Physicochemical Properties of Keratinocyte Membranes Exposed to UVA.

The action of UVA radiation (both that derived from solar radiation and that used in the treatment of skin diseases) modifies the function and composition of keratinocyte membranes. Therefore, this study aimed to assess the effects of phytocannabinoids (CBD and CBG), used singly and in combination, on the contents of phospholipids, ceramides, lipid rafts and sialic acid in keratinocyte membranes exposed to UVA radiation, together with their structure and functionality. The phytocannabinoids, especially in combination (CBD+CBG), partially prevented increased levels of phosphatidylinositols and sialic acid from occurring and sphingomyelinase activity after the UVA exposure of keratinocytes. This was accompanied by a reduction in the formation of lipid rafts and malondialdehyde, which correlated with the parameters responsible for the integrity and functionality of the keratinocyte membrane (membrane fluidity and permeability and the activity of transmembrane transporters), compared to UVA-irradiated cells. This suggests that the simultaneous use of two phytocannabinoids may have a protective effect on healthy cells, without significantly reducing the therapeutic effect of UV radiation used to treat skin diseases such as psoriasis.

A sustainable solution for diclofenac degradation from water by heterojunction bimetallic nanocatalyst

BackgroundDiclofenac (DCF), a recalcitrant pharmaceutical compound, poses severe environmental concerns due to several health hazards. The Fenton, photo-Fenton, and photo-Fenton-like processes are popular advanced oxidation processes for eliminating toxins from water bodies. Due to its high reactivity and surface properties, nanotechnology has opened newer technological advances in the Fenton-like advanced treatment processes. MethodA facile and one-pot synthesis produces the nanocomposite materials. The natural phytochemicals, in situ, produce the nanoparticles of Fe(NPs) and Ag(NPs), and bentonite is supported with these nanoparticles to create an innovative heterojunction nanocatalyst BN@(Fe(NPs)+(AgNPs)). Additionally, the batch investigations utilize these materials in the photo-Fenton-like degradation of diclofenac in aqueous mediums. Significant findingsThe heterojunction nanocatalyst showed synergistic effects in the remediation of DCF. The nanocatalyst is highly efficient in degrading the DCF (2.0 mg L−1) and removes 83 and 70% of DCF within 2 h under UV-A and LED light irradiations, respectively. Interestingly, the degradation process mineralizes DCF to 74% under UV-A irradiation. Moreover, degrading DCF in a heterogeneous light-assisted Fenton-like process was favorably influenced by increased Fe(II) concentration in the bulk solution. The BN@(Fe(NPs)+Ag(NPs)) nanocatalyst possessed reasonably high stability and reusability for practical applications. Further, the nanocatalyst showed relatively high selectivity in the degradation of DCF using two different natural water samples.

Assessing the electrochemical degradation of reactive orange 84 with Ti/IrO2–SnO2–Sb2O5 anode using electrochemical oxidation, electro-Fenton, and photoelectro-Fenton under UVA irradiation

Today, water shortage problems around the world have forced the search for new treatment alternatives, in this context, electrochemical oxidation technology is a hopeful process for wastewater treatment, although it is still needed exploration of new efficient and economically viable electrode materials. In this way, mixed metal oxide anodes look like promising alternatives but their preparation is still a significant point to study, searching for finding low-cost materials to improve electrocatalytic efficiencies. In an exploration of this kind of highly efficient materials, this work presents the results obtained using an MMO Ti/IrO2–SnO2–Sb2O5 anode. All the prepared anodes exhibited excellent physical and electrochemical properties. The electrochemical oxidation of 100 mL and 200 mg L−1 Reactive Orange 84 (RO 84) diazo dye was studied using 3 cm2 of such synthesized anodes by applying current densities of 25, 50, and 100 mA cm−2. Faster and more efficient electrochemical oxidation occurred at 100 mA cm−2 with 50 mM of Na2SO4 + 10 mM NaCl as supporting electrolyte at pH 3.0. The degradation and mineralization processes of the above solution were enhanced with the electro-Fenton process with 0.05 mM Fe2+ and upgraded using photoelectron-Fenton with UVA light. This process yielded 91% COD decay with a low energy consumption of 0.1137 kWh (g COD)−1 at 60 min. The evolution of a final carboxylic acid like oxalic was followed by HPLC analysis. The Ti/IrO2–SnO2–Sb2O5 is then an efficient and low-cost anode for the photoelectro-Fenton treatment of RO 84 in a chloride and sulfate media.

Optical properties of UV-C irradiated polyvinylidene chloride films

Polyvinylidene chloride (PVDC) polymer films were exposed to ultra-violet light (UV–C light of wavelength 254 nm) in air for different exposure times varying from 1 h up to 6 h. These films were characterized by using ultraviolet–visible (UV–Vis) and Fourier transform infrared (FTIR) spectroscopic, scanning electron microscopy (SEM), as well as powder X-ray diffraction (XRD) techniques. XRD scans reveal that the degree of crystallinity (Xc) increased from 4.7% up to 28.6% on increasing the UV exposure time from 1 h up to 4 h, and a further increase in the exposure time causes a decrease in its value. Analysis of the SEM images revealed an increase in particle size (chemically modified regions) on increased the UV exposure time of PVDC films from 1 h up to 6 h, and the maximum size of these regions were observed for an exposure time of 4 h. The SEM images showed a damaged PVDC surface, the formation of cotton-like fibrous regions, as well as many cracks due to the photo-degradation of polymeric chains. FTIR scans reveal the formation of hydrogen bonded hydroxyl groups as well as carbonyl structures in the PVDC sample on exposure to UV-C radiation. For the study of modification in band structure of the UV irradiated PVDC films, UV–Visible spectroscopy was used. It was found that the optical band gap decreases from 4.70 eV down to 3.92 eV, as obtained from the plot of √εihν versus hν. The penetration depth (δ) decreased from 0.0074 cm down to 0.0035 cm at 4.88eV, the energy corresponding to incident UV-C radiation. The calculation of percentage decrease in the value of δ with respect to wavelength and with variation in UV-C exposure time reveals that UV-C irradiated PVDC films are good radiation shields against both UV-A and UV-B electromagnetic radiation. The study of refractive index with respect to wavelength reveals that UV irradiation of PVDC films is an effective method to modify the refractive index of PVDC, thereby making the material more suitable for use in different optical applications. The optical dielectric constant was studied systematically, which indicated that the energy storage properties of the PVDC films can be tuned and tailored by UV-C radiation. Details are discussed.

The Impact of Routine Laundering on Ultraviolet Protection Factor (UPF) Values for Commercially Available Sun-Protective Clothing.

Background Ultraviolet (UV) radiation has potentially harmful effects on the skin. Sunscreen products have historically focused on blocking UV-B radiation to prevent sunburns while efforts to block UV-A radiation have been lacking. UV protective clothing, rated by ultraviolet protection factor (UPF) values, has gained popularity as an alternative form of UV protection, offering a physical barrier against UV rays. However, concerns arise regarding the disclosure and sustainability of UV-protective textiles, as companies often do not disclose the methods used to achieve UV protection. The addition of chemical sunscreen additives to textiles raises questions about their potential release during laundering and their impact on sustained UV protection and environmental health. Further research is needed to understand the risks and benefits of these practices. Methods Seven garments from commercially available sun-protective brand names claiming UV protection were tested for UPF values. The garments were washed separately using cold water in commercially available detergent in cold water followed by drying on a low setting. UPF measurements were obtained at baseline and at intervals of 10 wash cycles until 50 wash cycles were completed. Results Two brands (Brands A and D) experienced a significant decrease in UPF value (70% to 78%) by the completion of 50 washes. Brand A disclosed the use of a nano-zinc additive in their garments while Brand D did not disclose the means of achieving UV protection. In comparison, five brands (Brands B, C, E, F, G) maintained relatively stable UPF values throughout the 50 washes. The comparison between Brand A and Brand G, who disclosed their UV protectionmethods, showed that Brand A gradually decreased in UPF value throughout thewasheswhile Brand G remained stable. Conclusion The findings suggest that textile compositions with UV finishes may lose their UPF effectiveness during laundering by loss of the finish used over time or the textile integrity could be affected. This raises questions about the necessity of adding these UV finishes if there are fabrics that can maintain their UPF values without them.

Influence of photons of the near-ultraviolet radiation on the growth and development of sugar beet (<i>Beta vulgaris</i> L. ssp. <i>vulgaris var. saccharifera</i> Alef.) in a closed agrobiotechnosystem

Relevance and methodology. In order to determine the effect of near-ultraviolet radiation with a wavelength of 380 nm on the growth and development of a sugar beet hybrid plant, Smena was grown for 82 days under LED lighting with phytolamps and under conditions of increased UV-A intensity of the light range (an increase in the UV/PPFD ratio (0.027) compared with the control (0.0075) while maintaining the ratio of the remaining sites spectrum). The study was carried out on the basis of the digital software package "Synergotron" with a controlled internal environment.Results. An increase in the share of UV-A in the illumination spectrum leads to a significant change in the biometric indicators of plants – the aboveground biomass increases by 2.2 times compared to the control, and the mass of the underground part (root crops), on the contrary, decreases by 86.9%. At the same time, the share of root crops in the total biomass of plants decreases from 60% in the control to 30%. The morphological structure of the leaf apparatus changes: the proportion of petioles increases significantly compared to leaf blades (64.8% of petioles in aboveground biomass, whereas in the control 30%). Probably, an increase in the share of UV-A in the spectrum can favorably affect the cultivation of leaf forms of beets and other root crops. UV-A radiation leads to a change in the chemical composition of root crops, in particular, a decrease in the accumulation of dry substances (by 1.58%) and a decrease in sugar content (by 1.8%). An increase in the proportion of UV-A in the irradiation spectrum changes the parameters of chlorophyll fluorescence and contributes to an increase in the maximum quantum yield of Fv/Fm, non-photosynthetic quenching of NPQ fluorescence and a decrease in the real quantum yield of photosynthesis Y(II), as well as the electron transport rate (ETR).

Endogenous Photosensitizers in Human Skin.

Endogenous photosensitizers play a critical role in both beneficial and harmful light-induced transformations in biological systems. Understanding their mode of action is essential for advancing fields such as photomedicine, photoredox catalysis, environmental science, and the development of sun care products. This review offers a comprehensive analysis of endogenous photosensitizers in human skin, investigating the connections between their electronic excitation and the subsequent activation or damage of organic biomolecules. We gather the physicochemical and photochemical properties of key endogenous photosensitizers and examine the relationships between their chemical reactivity, location within the skin, and the primary biochemical events following solar radiation exposure, along with their influence on skin physiology and pathology. An important take-home message of this review is that photosensitization allows visible light and UV-A radiation to have large effects on skin. The analysis presented here unveils potential causes for the continuous increase in global skin cancer cases and emphasizes the limitations of current sun protection approaches.

Plant extracts-mediated green synthesis of zinc oxide/carbon nanofiber nanocomposites with highly efficient photocatalytic and antimicrobial properties for wastewater treatment

In the present study, a novel biosynthesis method for the preparation of zinc oxide/carbon nanofiber nanocomposite (ZnO-CNFs) is proposed along with evaluated their photocatalytic and antimicrobial properties for wastewater treatment. For biosynthesis of ZnO-CNFs, plant extracts of Thymus daenensis (TD) and Stachys pilifera Benth (SB) were used as both green-reducing agents and aqueous carbon-rich sources. The photocatalytic activity of the synthesized ZnO-CNFs was studied in the photodegradation of tetracycline antibiotic residues in contaminated water. The photocatalytic test (UVA irradiation, λ = 365 nm) results showed that the photodegradation efficiency of tetracycline by ZnO-CNFTD was 93.65 ± 2.1 %, 73.58 ± 1.5 %, 67.41 ± 1.7 %, and 81.28 ± 2.1 % in ultrapure water, infectious disease hospital 1, infectious disease hospital 2, and general hospital influents, respectively. Furthermore, the antimicrobial activity was examined against Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) bacteria and Candida albicans (C. albicans) fungus. To this end, the antibacterial behaviors of ZnO-CNFs were studied based on minimal inhibitory concentration (MIC) ranges and diameter of inhibition zone, which indicated that the ZnO-CNFs exhibited superior antibacterial activity against Gram-positive (B. subtilis) and Gram-negative (E. coli) bacteria compared to ZnO nanoparticles. Also, the antifungal activity of ZnO-CNFTD with MIC range of 156.25–625 μg mL−1 was more potent than ZnO nanoparticles with MIC range of 156.25–2500 μg mL−1. Overall, our findings indicate that the synthesized ZnO-CNFTD exhibits excellent photocatalytic and antimicrobial potential compared to ZnO nanoparticles and therefore can be a promising candidate for effective treatment of water contaminated with microorganisms and organic compounds.

Boosting Tetracycline Degradation with an S-Scheme Heterojunction of N-Doped Carbon Quantum Dots-Decorated TiO2.

N-doped carbon quantum dots (N-CQDs) derived from the Rumex crispus L. plant were incorporated into TiO2 via a facile hydrothermal method. As-prepared materials were characterized and used in the photocatalytic tetracycline (TC) degradation under UVA light irradiation by examining several operational parameters involving the N-CQDs amount, initial TC concentration, pH, and photocatalytic reaction time. XRD analysis revealed the conversion of the rutile phase to the anatase phase after the incorporation of N-CQDs into the TiO2 structure. The results revealed that the N-CQDs/TiO2 photocatalysts demonstrated the highest efficiency in TC degradation compared to other processes of adsorption, photolysis (UVA), and photocatalysis with TiO2 (TiO2/UVA). Under optimized conditions, 10 mg/L TC at pH 5.15 with 0.2 g/L N-CQDs/TiO2 catalyst showed 97.7% photocatalytic degradation for 120 min under UVA irradiation. The formation of an S-scheme heterojunction between N-CQDs and TiO2 provided enhanced charge separation and strong redox capability, causing significant improvement in the photocatalytic performance of N-CQDs/TiO2. Trapping experiments showed that O2•- and h+ are the predominant reactive species for the TC elimination in an aqueous solution.

Carbon nitride exfoliation for photocatalysis and photocatalytic ozonation over emerging contaminants abatement

The production of graphitic carbon nitride was studied with the addition of a following exfoliation step using ultrasounds, at different times. The treatment produced catalysts with much higher surface areas, from 2.18 m2 g−1 with no treatment to 28.34 m2 g−1 after 36 h of exfoliation. During exfoliation, melem was also produced, and may further enhance the photoluminescence and photocatalytic properties. The photocatalytic reaction also indicated the improved performance of exfoliated g-C3N4 towards the degradation of a mixture of parabens, enhancing their removal from 20% to up to 65% in 2 h under UVA radiation. The combination of ozone and g-C3N4 photocatalysis was able to completely remove the parabens in under 8 min and with a 20% lower consumption of ozone compared to photolytic ozonation. The main reactive species were identified, and the by-products formed during parabens degradation were detected. The efficiency of the combined system was also attested by using a mixture of parabens and other common drugs, maintaining its better performance.

The Addition of TiO2 Ratios in SiO2–TiO2 Nanocomposite by Sonochemical Process for the Enhancement in Self-cleaning Property

This research aims to study self-cleaning property for removing atmosphere pollutants on the substrate surface. Thus, the modification of nanocomposite material for self-cleaning property is an important challenge to solving the organic pollutants on various surfaces. Nanocomposite material in this work is focused on SiO2-TiO2 based metal oxide materials that synthesized by sonochemical process with the precursors of tetraethyl orthosilicate (TEOS) and titanium isopropoxide (TTIP). The crucial parameter of different amount of titanium ratios in SiO2 matrix is related to the improvement on structural and self-cleaning properties. The ratios of Si:Ti precursor were varied at 1:0.1, 1:0.5, 1:1 and 0:1 (pure TiO2). The structural phase of SiO2-TiO2 nanocomposite powder was detected by X-ray diffraction technique (XRD). Chemical bonding structure in SiO2-TiO2 nanocomposite was analysed by Fourier transform infrared spectrophotometer (FTIR). Surface morphology of SiO2-TiO2 nanocomposite was monitored by field emission scanning electron microscope (FE-SEM). SiO2-TiO2 nanocomposites synthesized by sonochemical process were in form of composite powder with the spherical SiO2 particles and decorated TiO2 on its surface. After that, the products of SiO2-TiO2 nanocomposite with different TiO2 ratios were mixed with TES 40 WN solution and deposited on glass slides substrate by spray coating to study its hydrophilic property by contact angle method. The contact angle of SiO2-TiO2 nanocomposite film was reduced with the increase of Ti ratio in SiO2 matrix resulting to the development of hydrophilic surface on substrate. The influence of TiO2 in SiO2 matrix on self-cleaning and property would be improved by hydroxyl groups on the composite surface corresponding to Ti–O–Si linkages. For self-cleaning property, Si:Ti ratio at 1:1 in SiO2-TiO2 nanocomposite showed the optimized condition with decreasing contact angle at 28.97 degree in 60 min after UVA irradiation.

Involvement of type-1 pathway in phototoxicity of benzo[ghi]perylenean ingredient of tattoo ink at ambient exposure of UVR and sunlight.

Tattooing on different parts of the body is a very common fashion trend in all sections of society globally. Skin allergies and other related skin diseases are very common among tattoo users. Benzo[ghi]perylene (BP) is a PAH and an important component of tattoo ink that showed prominent absorption under ultraviolet radiation (UVR) region. Therefore, to provide safety to the skin, a thorough safety study of BP exposed under UVR and Sunlight is very essential to understand their hazardous impact on the skin. BP showed a strong absorption of UVA and UVB radiation of sunlight. It is photolabile and degraded under UVA, UVB, and Sunlight in progressing order of time (1-4 h) without generating any novel photoproducts. Further, BP showed a specific generation of O2.- and OH radicals via activation of type I photodynamic reaction under exposure to UVA, UVB and Sunlight. Photocytotoxicity results illustrated concentration-dependent cell viability reduction in all exposure conditions of UVA, UVB, and Sunlight, respectively. Fluorescent probes (2',7'-dichlorofluorescein diacetate and dihydroethidium) for intracellular reactive oxygen species (ROS) generation supported the involvement of ROS in the phototoxicity of BP in the HaCaT cell line. Hoechst staining showed significant genomic insult induced by BP under UVA and UVB. Photoexcited BP promoted cell cycle arrest in the G1 phase and induced apoptosis confirmed via acridine orange/ethidium bromide staining. The findings of gene expression also supported apoptotic cell death in photoexcited BP via an increase in the level of pro-apoptotic gene (Bax) and a decrease in the level of anti-apoptotic gene (Bcl-2). The aforementioned finding indicates that tattoo users should avoid using BP since it can cause skin damage/diseases if they are exposed to UVR or Sunlight while tattooing on the body.

Comparison of Cloud Optical Thickness of GK-2A and HIMAWARI Satellites by Using UV-A Irradiance in Daejeon

Comparison of Cloud Optical Thickness of GK-2A and HIMAWARI Satellites by Using UV-A Irradiance in Daejeon

Attenuating UVA-induced oxidative stress of human skin fibroblasts by enhancing bioactive components of Armillaria luteo-virens by Lactobacillus delbrueckii subsp. Bulgaricus fermentation

In this study, we demonstrated that the fermentation of Armillaria luteo-virens with Lactobacillus delbrueckii subsp. bulgaricus has a protective effect on human skin fibroblasts (HSFs) irradiated by UVA. We studied the fermentation broth of Armillaria luteo-virens (FBA) at the structural, cellular and genetic levels, and found that the content of polysaccharides in FBA increased, and the molecular weight of polysaccharides decreased by fermentation. After FBA pretreatment, we irradiated the cells with UVA, and found that the antioxidant capacity of the cells was significantly enhanced, and the activity of mitogen activated protein kinase (MAPK) pathway induced by UVA was weakened. The secretion of tissue inhibitory metalloproteinases (TIMPs) was inhibited, which decreased the activity of matrix metalloproteinases (MMPs) and increased the content of type I collagen (COL-I). Experiments have proved that FBA can enhance the antioxidant capacity and reduce the oxidative stress caused by UVA irradiation, giving it prevention potential against the photoaging process.

Protective Effect of Amaranthus cruentus L. Seed Oil on UVA-Radiation-Induced Apoptosis in Human Skin Fibroblasts

Since the exposure of fibroblasts to prolonged UVA radiation induces oxidative stress and apoptosis, there is a need for effective skin protection compounds with cytoprotective and antioxidant properties. One of their sources is Amaranthus cruentus L. seed oil (AmO), which is rich in unsaturated fatty acids, squalene, vitamin E derivatives and phytosterols. The aim of this study was to evaluate whether AmO evokes a protective effect on the apoptosis induced by UVA radiation in human skin fibroblasts. UVA radiation at an applied dose of 10 J/cm2 caused a significant reduction in the survival of human skin fibroblasts and directed them into the apoptosis pathway. Increased expression of p53, caspase-3, caspase-9 and PARP proteins in UVA-treated fibroblasts suggests the intrinsic mechanism of apoptosis. Application of the oil at 0.1% and 0.15% concentrations to UVA-treated cells decreased the expression of these proteins, which was accompanied by increased cell survival. Similarly, the UVA-dependent decrease in the expression of p-Akt and mTOR proteins was restored under the effect of the studied oil. The molecular mechanism of this phenomenon was related to the stimulation of antioxidant processes through the activation of Nrf2. This suggests that AmO stimulated the antioxidant system in fibroblasts, preventing the effects of UVA-induced oxidative stress, which may lead to pharmaceutical and cosmetological applications as a sun-protective substance.

Straightforward sonoelectrochemical synthesis of TiO2 nanoparticles for photocatalytic removal of Cr(VI) in water

This work proposed a highly efficient sonoelectrochemical technique for the straightforward synthesis of TiO2 nanoparticles (NPs) at a mild temperature of 60 °C under an atmosphere environment. The NPs were then applied for photocatalytic removal of Cr(VI) in an aqueous solution. The NPs possess an anatase crystalline phase with a particle size of about 6.5 nm and a superior surface area of 202.85 m2/g and exhibit good photocatalytic reduction of Cr(VI) under UVA irradiation.