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Many determinants of vitamin D status have been well-described, yet supplementation guidelines largely follow a one-size-for-all model and deficiency remains common. We hypothesised that accounting accurately for ultraviolet-B (UVB) radiation and considering interactions could advance understanding of vitamin D status. Asian, Black, and White participants from the UK Biobank cohort were included (N = 438,978). The Tropospheric Emission Monitoring Internet Service provided UVB data which we linked to participants' place of residence. UVB dose over 135 days prior to blood draw was weighted and added, yielding cumulative and weighted UVB (CW-D-UVB). The association between 25(OH)D and selected variables was assessed in multivariable linear regression models with and without interactions, stratified by ethnicity. Predictors were ranked using standardised β-coefficients. Median 25(OH)D differed by ethnicity (Asian: 25.4 nmol/L (10.2 ng/mL), Black: 30.6 nmol/L (12.2 ng/mL), White: 47.9 nmol/L (19.2 ng/mL), p-value < 0.001). CW-D-UVB was strongly associated with 25(OH)D in all ethnicities. It was the most important predictor in White (β Asian = 0.15, β Black = 0.20, β White = 0.35), whereas supplementation was in Asian and Black participants (β Asian = 0.30, β Black = 0.24, β White = 0.21). We identified statistically significant interactions between BMI:supplementation (all), CW-D-UVB:sex (Asian and White), and CW-D-UVB:age (Black and White), and in White population between CW-D-UVB and supplementation, BMI, and cholesterol. Vitamin D deficiency was widespread, particularly among non-White individuals. UVB was a strong predictor of 25(OH)D and the effect was modified by other factors. Findings suggest that accurately measured ambient-UVB radiation and interactions could improve 25(OH)D prediction models, and support personalised approaches to vitamin D optimisation. [ABSTRACT FROM AUTHOR]

The current study examined the impact of ultraviolet (UV)‐B radiation in Metarhizium pingshaense blastospores' photolyase expression and their virulence against Rhipicephalus microplus. Blastospores were exposed to UV under laboratory and field conditions. Ticks were treated topically with fungal suspension and exposed to UV‐B in the laboratory for three consecutive days. The expression of cyclobutane pyrimidine dimmers (CPDs)‐photolyase gene maphr1‐2 in blastospores after UV exposure followed by white light exposure was accessed after 0, 8, 12, 24, 36, and 48 h. Average relative germination of blastospores 24 h after in vitro UV exposure was 8.4% lower than 48 h. Despite this, the relative germination of blastospores exposed to UV in the field 18 h (95.7 ± 0.3%) and 28 h (97.3 ± 0.8%) after exposure were not different (p > 0.05). Ticks treated with fungus and not exposed to UV exhibited 0% survival 10 days after the treatment, while fungus‐treated ticks exposed to UV exhibited 50 ± 11.2% survival. Expression levels of maphr1‐2 8, 12, and 24 h after UV‐B exposure were not different from time zero. Maphr1‐2 expression peak in M. pingshaense blastospores occurred 36 h after UV‐B exposure, in the proposed conditions and times analyzed, suggesting repair mechanisms other than CPD‐mediated‐photoreactivation might be leading blastospores' germination from 0 to 24 h. [ABSTRACT FROM AUTHOR]

The Antarctic environment is extremely cold, windy and dry. Ozone depletion has resulted in increasing ultraviolet-B radiation, and increasing greenhouse gases and decreasing stratospheric ozone have altered Antarctica's climate. How do mosses thrive photosynthetically in this harsh environment? Antarctic mosses take advantage of microclimates where the combination of protection from wind, sufficient melt water, nutrients from seabirds and optimal sunlight provides both photosynthetic energy and sufficient warmth for efficient metabolism. The amount of sunlight presents a challenge: more light creates warmer canopies which are optimal for photosynthetic enzymes but can contain excess light energy that could damage the photochemical apparatus. Antarctic mosses thus exhibit strong photoprotective potential in the form of xanthophyll cycle pigments. Conversion to zeaxanthin is high when conditions are most extreme, especially when water content is low. Antarctic mosses also produce UV screening compounds which are maintained in cell walls in some species and appear to protect from DNA damage under elevated UV-B radiation. These plants thus survive in one of the harshest places on Earth by taking advantage of the best real estate to optimise their metabolism. But survival is precarious and it remains to be seen if these strategies will still work as the Antarctic climate changes. [ABSTRACT FROM AUTHOR]

Sophora flavescens has been used in traditional medicine for the treatment of various diseases such as viral hepatitis, fever, cancer, and pain. It is known to contain many bioactive compounds including prenylated flavonoids such as kurarinone, sophoraflavanone G, kuraridine and isoxanthohumol. These flavonoids have been confirmed to have anti-inflammatory, α-glucosidase inhibitory and antioxidant performances. However, the protective activities against UV-induced skin damage of kushenol C from S. flavescens have not yet been elucidated. In this study, we explored the protective effect of kushenol C against the skin damage induced by UVB in mice. Our results showed that kushenol C treatment significantly recovered UVB-induced skin damage, the degradation of collagen, mast cell infiltration, together with epidermal hyperplasia in mice. Furthermore, the treatment of kushenol C remarkably suppressed the generation of pro-inflammatory mediators in the mice irradiated by UVB. More so, treatment with kushenol C suppressed the oxidative stress in mice irradiated by UVB. In conclusion, these results showed that kushenol C from S. flavescens has potentialities to treat skin injury via suppressing skin damage induced by UVB and oxidative stress.

Ultraviolet radiation (UVR) is generally considered a primary tumorigenic agent. While UVR exposure has been studied, especially at the skin level, the impact of UV exposure on internal tissues and its effect on the appearance and the development of tumors has not yet been fully examined. Although there are maximum limits for UVR exposure on external tissues, other internal tissues, such as oral tissue, can be exposed to UVR as well. Over the course of diagnosis and treatment, oral cells may be exposed to ultraviolet radiation; however, there has not been an established limit for UV radiation exposure. Therefore, the aim of the current study was to examine the effects of ultraviolet-B (UVB) radiation at two doses (2.5 and 5 J/cm2) on tumor cells (pharyngeal carcinoma and tongue carcinoma) and healthy cells (gingival fibroblasts). The viability of the cells and their morphology, actin filaments, and nuclei structures; the expression of anti-apoptotic (Bcl-2) and pro-apoptotic (Bax) genes; and the roles of caspases-3/7, 8, and 9 were determined after the cells had been exposed to UVB. The experiments revealed that both types of cell lines showed reductions in viability, especially at a dose of 5 J/cm2. Additionally, apoptotic-like changes (rounding of the cells, the condensation of the nuclei, the re-organization of the actin filaments) were observed in all analyzed cells. The expression of anti-apoptotic (Bcl-2) and pro-apoptotic (Bax) genes revealed that UVB (5 J/cm2) may induce apoptosis in both oral tumor and healthy cells. Moreover, an analysis of caspases-3/7, 8, and 9 showed that UVB exposure enhanced their activity, suggesting that cell death could be caused by both intrinsic and extrinsic apoptosis. Accordingly, UVB exposure at the maximum doses used in dental practices (5 J/cm2) induced nonselective apoptotic changes, thereby reducing both tumor and healthy cell viability. [ABSTRACT FROM AUTHOR]

Global climate change continues to leave irreversible effects worldwide. With the increase in the effects of climate change, especially in recent years, the amount of UV-B radiation reaching the earth's surface is also likely to increase. With increasing temperatures, the amount of precipitation in the world has decreased, and the drought has started to alarm. This study is tried to understand how plants can respond to these stresses using ash-leaf maple (Acer negundo L.) and sycamore maple (Acer pseudoplatanus L.) species. The effects of these stress factors on plant leaf morphology were investigated by applying certain intensities of drought (moderate [T2] and severe drought [T3]) and UV-B (8 kJ m-2 h-1 [T4] and 12 kJ m-2 h-1 [T5]) stresses on these two species with T1 (control) treatment. As a result, leaf width in A. pseudoplatanus species was at the lowest levels in individuals exposed to T3 and T9. In A. negundo species, leaflet length in T1, T2, T3, T4 T5, T6 (modarete+T4), T7 (modarete+T5), T8 (severe drought+T4), and T9 (severe drought+T5) treatment were 8.800, 8.704, 8.075, 8.792, 8.823, 8.516, 8.317, 7.993, and 8.605 cm, respectively. According to these values, it was observed that the leaflet length was the shortest in T8 (7.993 cm) treatment. On the other hand, the leaflet length in T9 was close to the T1 group. As a result, individuals exposed to T4 were more affected than T5 in applications applied to UV-B stress and T3. Therefore, the increase of UV-B radiation positively affects the plant's resistance to drought stress.

Abiotic environmental stresses can alter plant metabolism, leading to inhibition or promotion of secondary metabolites. Although the crucial roles of these compounds in plant acclimation and defense are well known, their response to climate change is poorly understood. As the effects of climate change have been increasing, their regulatory aspects on plant secondary metabolism becomes increasingly important. Effects of individual climate change components, including high temperature, elevated carbon dioxide, drought stress, enhanced ultraviolet-B radiation, and their interactions on secondary metabolites, such as phenolics, terpenes, and alkaloids, continue to be studied as evidence mounting. It is important to understand those aspects of secondary metabolites that shape the success of certain plants in the future. This review aims to present and synthesize recent advances in the effects of climate change on secondary metabolism, delving from the molecular aspects to the organismal effects of an increased or decreased concentration of these compounds. A thorough analysis of the current knowledge about the effects of climate change components on plant secondary metabolites should provide us with the required information regarding plant performance under climate change conditions. Further studies should provide more insight into the understanding of multiple environmental factors effects on plant secondary metabolites. [ABSTRACT FROM AUTHOR]

Atmospheric conditions, as well as pollutants, can induce changes in the viability and germinability of the pollen grain. This process frequently occurs in cities due to the high rate of air pollution that can alter the quality of pollen, affecting its biological functions. In this work, the effect of different environmental stress factors, mainly UV-B radiation and polluting gases (CO, NO2 and SO2), on the viability and maturity of the pollen of four ornamental tree-species present in the green infrastructure of Granada, namely Acer negundo, Carpinus betulus, Olea europaea and Cupressus spp. is analyzed. Differential staining techniques were used with fresh pollen collected in areas with different exposure to environmental stress to detect intact cell membranes (Trypan blue) and the state of maturity (Pyrogallol red). It was observed that the species from sectors more exposed to environmental stress registered a low viability and were affected by factors such as UV-B radiation and atmospheric pollutants. On the contrary, the pollen from tree species growing in peri-urban forests presented a higher rate of viability and less effect of pollutant factors. Differences were also observed according to the species/genus and according to the sampling area. This modification in the morphological and/or organic composition of the pollen wall may cause a loss of quality in the reproductive processes of plants, and it may be bioindicator of the process of progressive degradation that plant species can experience in urban environments under conditions of environmental stress, and prevent the impacts that can affect other species. [ABSTRACT FROM AUTHOR]

Elevated ultraviolet radiation (UVR) is postulated as one of multiple, interrelated environmental stressors driving amphibian population declines globally. However, key knowledge gaps remain in elucidating the link between elevated UVR and amphibian declines in a changing climate, including whether timing and irradiance of UVR exposure in early life dictates the onset of detrimental carryover effects post-metamorphosis. In this study, striped marsh frog larvae (Limnodynastes peronii) were exposed to UVR at one of two different irradiances for up to 7 days, either as hatchlings (Gosner stage 23) or as older larvae (Gosner stage 25-28). These animals were then reared to metamorphosis in the absence of UVR to examine independent and interactive carryover effects throughout development. Older larvae were more sensitive to UVR than hatchlings, with 53.1% and 15.6% mortality in larvae exposed to high and low irradiance respectively, compared with no mortality of hatchlings in either irradiance treatment. Irradiance and timing of UVR exposure had interactive effects on larval body length, causing stunted growth patterns and a lack of compensatory growth following UVR exposure, particularly in animals exposed to high irradiance UVR later in development. Timing of UVR exposure also determined the severity of carryover effects into metamorphosis, including delayed metamorphosis and the first published account (to our knowledge) of latent UVR-induced depigmentation in an amphibian. These findings highlight how acute changes to the larval UVR exposure regime can impact on amphibian health later in life, with implications for our understanding of the effects of climate change on UVR-related amphibian declines., (© 2024 Wiley Periodicals LLC.)

The ultraviolet–B (UV–B) radiation is harmful to the aquatic organisms. The UV–B protective properties of leaves and seeds of herb Achyranthes aspera were evaluated in Clarias batrachus. Fish were fed with four diets—EFL1, EFL2 containing 0.25 and 0.5% leaves, EFS containing 0.5% seeds and control, CF. After 83 days of feeding, fish were exposed to UV–B (157 µW/cm2) for 7 days at the rate of 15 min/day. One batch of fish in each treatment was kept unexposed. Significantly higher final weight was found in EFS followed by EFL2 and EFL1 treatments. It was higher in unexposed fish compared to the exposed ones. Among exposed fish, significantly higher lysozyme was found in EFS and myeloperoxidase in EFS and EFL2 compared to others. Nitric oxide synthase and superoxide dismutase levels were significantly higher in liver and head kidney of EFS diet fed fish compared to others. Thiobarbituric acid reactive substances (TBARS) and carbonyl protein levels were minimum in EFS followed by EFL2. The independent sample t-test showed that nitric oxide synthase was significantly higher and myeloperoxidase and TBARS levels were significantly lower in unexposed group compared to the exposed fish in respective treatment. There were up-regulations of TNF-α, iNOS, NF-kB, BAX, Cytochrome c, SOD-c, Caspase 3, Caspase 9, BCL2 in liver and head kidney of leaves and seeds incorporated diets fed fish compared to control. Supplementation of A. aspera seeds and leaves at 0.5% level in diets gave UV–B protection to the fish. [ABSTRACT FROM AUTHOR]

The Rhizobium-legume symbiosis plays an important role in improving soil fertility and crop productivity, particularly in inherently poor soils in developing countries. However, nodulation and symbiotic nitrogen fixation in tropical legumes might be reduced due to the climate change-driven increases in ultraviolet-B (UV-B) radiation. Hence, a greenhouse experiment was conducted to evaluate the effect of UV-B radiation on two cowpea varieties inoculated with a Bradyrhizobium strain. The treatments studied consisted of two cowpea varieties (Keti (IT99K-1122) and TVU), two levels of inoculation (control and inoculated with Bradyrhizobium strain CP-24), and two UV-B radiation levels (ambient and 0.4 W m−2 supplement) laid out in a completely randomized design with three replications. The 15 N natural abundance technique was used to estimate the symbiotic N2-fixation. Analysis of variance showed that treatments markedly affected cowpea varieties' performance, and varieties responded differently to elevated UV-B radiation. Of the two varieties, Keti produced more nodules and nodule dry weight, but the TVU variety excelled in shoot biomass, shoot N content, and fixed-N. Inoculation markedly increased shoot biomass, nodule dry weight, shoot N content, and amount of N fixed. On the other hand, the supplemented UV-B radiation caused a significant reduction in nodule number (55%), nodule dry weight (74%), shoot biomass (22%), shoot N content (18%), and amount of fixed-N (19%) compared to the plants grown under ambient UV-B condition. These findings, therefore, indicate the need for identifying improved UV-B resistant varieties and inoculants with UV-B effect nullifying capacity to minimize the current and projected UV-B radiation effect on symbiotic nitrogen contribution of nodulating legumes during climate change times. [ABSTRACT FROM AUTHOR]

Keywords: Antarctica; bushfires; climate change; climate forcing; ozone depletion; sea ice; ultraviolet-B radiation; UV-B EN Antarctica bushfires climate change climate forcing ozone depletion sea ice ultraviolet-B radiation UV-B 61 63 3 05/16/23 20230401 NES 230401 In the 1980s, British Antarctic scientists (Farman I et al. i [7]) discovered the hole in the ozone layer over Antarctica, and we are now familiar with images of springtime ozone depletion extending beyond the continental margins (Fig. Antarctica, bushfires, climate change, climate forcing, ozone depletion, sea ice, ultraviolet-B radiation, UV-B However, there is still reason to be concerned about the timing and extent of ultraviolet (UV) radiation exposure in Antarctica, as well as how ozone recovery may be jeopardized by climate change-mediated events such as wildfires. [Extracted from the article]

Over the past few decades, anthropogenic activities contributed to the depletion of the ozone layer, which increased the levels of solar ultraviolet-B (UV-B) radiation reaching the Earth`s surface. Generally, UV-B is harmful to all living organisms. It damages the cell`s Deoxyribonucleic acid (DNA), proteins, and lipids, and as a consequence, it affects the bio-membranes negatively. In this review, we summarize the major effects of UV-B in the plant`s main molecules and physiological reactions, in addition to the possible defence mechanisms against UV-B including accumulating UV-B absorbing pigments to alleviate the harmful impact of UV-B.

Ultraviolet radiation (UVR) is generally considered a primary tumorigenic agent. While UVR exposure has been studied, especially at the skin level, the impact of UV exposure on internal tissues and its effect on the appearance and the development of tumors has not yet been fully examined. Although there are maximum limits for UVR exposure on external tissues, other internal tissues, such as oral tissue, can be exposed to UVR as well. Over the course of diagnosis and treatment, oral cells may be exposed to ultraviolet radiation; however, there has not been an established limit for UV radiation exposure. Therefore, the aim of the current study was to examine the effects of ultraviolet-B (UVB) radiation at two doses (2.5 and 5 J/cm2) on tumor cells (pharyngeal carcinoma and tongue carcinoma) and healthy cells (gingival fibroblasts). The viability of the cells and their morphology, actin filaments, and nuclei structures; the expression of anti-apoptotic (Bcl-2) and pro-apoptotic (Bax) genes; and the roles of caspases-3/7, 8, and 9 were determined after the cells had been exposed to UVB. The experiments revealed that both types of cell lines showed reductions in viability, especially at a dose of 5 J/cm2. Additionally, apoptotic-like changes (rounding of the cells, the condensation of the nuclei, the re-organization of the actin filaments) were observed in all analyzed cells. The expression of anti-apoptotic (Bcl-2) and pro-apoptotic (Bax) genes revealed that UVB (5 J/cm2) may induce apoptosis in both oral tumor and healthy cells. Moreover, an analysis of caspases-3/7, 8, and 9 showed that UVB exposure enhanced their activity, suggesting that cell death could be caused by both intrinsic and extrinsic apoptosis. Accordingly, UVB exposure at the maximum doses used in dental practices (5 J/cm2) induced nonselective apoptotic changes, thereby reducing both tumor and healthy cell viability.

Exposure to ultraviolet-B (UV-B) radiation can lead to oxidative damage in plants, increasing reactive oxygen species (ROS) production. To overcome ROS burst, plants have antioxidant mechanisms related to ROS scavenging which can be improved by elicitation with biological agents or derived molecules (elicitors), as they can trigger a physiological alert state called "priming". This work describes the effects of lipo-chitooligosaccharides (LCOs) treatment applied to tomato plants under UV-B stress. The LCOs used in the study are produced by three species of the genus Ensifer (formerly Sinorhizobium) (SinCEU-1, SinCEU-2, and SinCEU-3) were assayed on tomato plants under UV-B stress. LCOs were able to significantly increase most of the enzymatic activities related to ROS scavenging while non-enzymatic antioxidants were not modified. This response was associated with a lower oxidative stress, according to malondialdehyde (MDA) levels and the higher antioxidant capacity of the plants. Furthermore, the photosynthetic efficiency of LCOs-treated plants indicated a better physiological state than the control plants. Therefore, although more studies and deepening of certain aspects are necessary, LCOs have shown great potential to protect plants from high UV-B radiation conditions. [ABSTRACT FROM AUTHOR]

The interest in the pre-harvest ultraviolet-B (UV-B) exposure of crops in indoor cultivation has grown consistently, though very little is known about its influence on the nutraceutical quality of microgreens. Flaxseeds constitute a valuable oilseed species, mostly appreciated for their nutritional properties and the presence of health-promoting compounds. Therefore, although scarcely studied, flaxseed sprouts and microgreens might constitute a high-quality food product to be included in a healthy diet. This study aims to unravel the effects of pre-harvest ultraviolet-B irradiation on the nutritional and nutraceutical quality of flaxseed sprouts and microgreens grown under artificial conditions. The UV-B irradiation decreased the biomass and stem length of microgreens. However, the content of total phenolics and flavonoids and the antioxidant capacity were strongly enhanced by the UV-B treatment in both sprouts and microgreens. Among photosynthetic pigments, chlorophyll a, violaxanthin, antheraxanthin, and lutein in sprouts were reduced by the treatment, while chlorophyll b increased in microgreens. In conclusion, our results showed that growing flaxseed sprouts and microgreens in controlled conditions with supplemental UV-B exposure might increase their nutritional and nutraceutical quality, as well as their antioxidant capacity, making them high-quality functional foods. [ABSTRACT FROM AUTHOR]

Mahonia bealei (M. bealei) is a traditional Chinese medicine containing a high alkaloid content used to treat various diseases. Generally, only dried root and stem are used as medicines, considering that the alkaloid content in M. bealei leaves is lower than in the stems and roots. Some previous research found that alkaloid and flavonoid contents in the M. bealei leaves may increase when exposed to ultraviolet B (UV-B) radiation. However, the underlying mechanism of action is still unclear. In this study, we used titanium dioxide material enrichment and mass-based label-free quantitative proteomics techniques to explore the effect and mechanism of M. bealei leaves when exposed to UV-B treatment. Our data suggest that UV-B radiation increases the ATP content, photosynthetic pigment content, and some enzymatic/nonenzymatic indicators in the leaves of M. bealei. Moreover, phosphoproteomics suggests phosphoproteins related to mitogen-activated protein kinase (MAPK) signal transduction and the plant hormone brassinosteroid signaling pathway as well as phosphoproteins related to photosynthesis, glycolysis, the tricarboxylic acid cycle, and the amino acid synthesis/metabolism pathway are all affected by UV-B radiation. These results suggest that the UV-B radiation activates the oxidative stress response, MAPK signal transduction pathway, and photosynthetic energy metabolism pathway, which may lead to the accumulation of secondary metabolites in M. bealei leaves. [ABSTRACT FROM AUTHOR]

Purpose: Ultraviolet-B radiation was inducing enormous stress at highland and coldest area since it increases more than 40% at highland when we compare with lowland. Therefore, this review aims to assess and depict impacts of Ultraviolet-B radiation on photosynthetic efficiency, growth performance, and yield of crops based on altitude. Findings: Indicate that ultraviolet-b radiation has a severe effect on photosynthesis, especially the coldest time. It reduces photosynthetic efficiency in such an area, but it depends on the type of the crop and cultivar difference. On the other hand, it reduces growth performance and biomass accumulation based on altitude. There is a contrasting view on a net-assimilation rate on different studies condition. The effect of UV-B on crop yield was more contrasting in some studies says no effect on other studies it says it affect, but this contradictory result was mainly due to the difference in study conditions, still current studies on Yield revealed that UV-B has a high impact on yield. Research limitations: Ultraviolet-B radiation has high effect on the highland area, but there is no much research focuses, but UV-B was profoundly affecting photosynthetic efficiency, growth performance and yield of crops on highland area. Directions for future research: UV-B was reducing crop production, and productivity at highland and this review gives more insights on UV-B impact at the highland and allow UV-B adaptive and preventive investigation in the future.

Objective: To study the protective effect of ascorbic acid and curcumin against the abnormal estrous cycle and morphological changes in cells induced by repeated ultraviolet B (UVB) radiation in female Wistar rats. Methods: Sixteen female sexually mature Wistar rats weighing 130-150 g and aged 12-16 weeks were randomly divided into four groups. The control group received normal food and water ad libitum. The UVB group was exposed to a dose of 280 nm of UVB radiation for 2 h daily. The UVB+curcumin group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of curcumin (25 mg/kg body weight) daily. The UVB+ascorbic acid group received a dose of 280 nm of UVB radiation for 2 h daily and also an oral dose of ascorbic acid (250 mg/kg body weight) daily. All the treatments last for 15 consecutive days. Body and ovary weight and gonadosomatic index were measured. The stages (proestrus, estrus, metaestrus and diestrus) of the estrous cycle were determined by the cell types observed in the vaginal smear. Results: UVB radiation caused irregular alterations on the estrous cycle and morphological changes of the female Wistar rat as compared with the control group. Ascorbic acid and curcumin protected UVB-induced estrous phases and their cells. But curcumin showed greater protection than ascorbic acid. Conclusions: Ascorbic acid and curcumin at low doses can alleviate abnormal estrous cycle and morphological changes in cells induced by UVB radiations in female Wistar rats.

Mahonia bealei (M. bealei) is a traditional Chinese medicine containing a high alkaloid content used to treat various diseases. Generally, only dried root and stem are used as medicines, considering that the alkaloid content in M. bealei leaves is lower than in the stems and roots. Some previous research found that alkaloid and flavonoid contents in the M. bealei leaves may increase when exposed to ultraviolet B (UV-B) radiation. However, the underlying mechanism of action is still unclear. In this study, we used titanium dioxide material enrichment and mass-based label-free quantitative proteomics techniques to explore the effect and mechanism of M. bealei leaves when exposed to UV-B treatment. Our data suggest that UV-B radiation increases the ATP content, photosynthetic pigment content, and some enzymatic/nonenzymatic indicators in the leaves of M. bealei. Moreover, phosphoproteomics suggests phosphoproteins related to mitogen-activated protein kinase (MAPK) signal transduction and the plant hormone brassinosteroid signaling pathway as well as phosphoproteins related to photosynthesis, glycolysis, the tricarboxylic acid cycle, and the amino acid synthesis/metabolism pathway are all affected by UV-B radiation. These results suggest that the UV-B radiation activates the oxidative stress response, MAPK signal transduction pathway, and photosynthetic energy metabolism pathway, which may lead to the accumulation of secondary metabolites in M. bealei leaves.

Bryophytes are the dominant vegetation in the Antarctic continent. They have suffered more unpleasant ultraviolet radiation due to the Antarctic ozone layer destruction. However, it remains unclear about the molecular mechanism of Antarctic moss acclimation to UV-B light. Here, the transcriptomics and metabolomics approaches were conducted to uncover transcriptional and metabolic profiling of the Antarctic moss Leptobryum pyriforme under UV-B radiation. Totally, 67,290 unigenes with N50 length of 2,055 bp were assembled. Of them, 1,594 unigenes were significantly up-regulated and 3353 unigenes were markedly down-regulated under UV-B radiation. These differentially expressed genes (DEGs) involved in UV-B signaling, flavonoid biosynthesis, ROS scavenging, and DNA repair. In addition, a total of 531 metabolites were detected, while flavonoids and anthocyanins accounted for 10.36% of the total compounds. There were 49 upregulated metabolites and 41 downregulated metabolites under UV-B radiation. Flavonoids were the most significantly changed metabolites. qPCR analysis showed that UVR8-COP1-HY5 signaling pathway genes and photolyase genes (i.e., LpUVR3 , LpPHR1 , and LpDPL) were significantly up-regulated under UV-B light. In addition, the expression levels of JA signaling pathway-related genes (i.e., OPR and JAZ) and flavonoid biosynthesis-related genes were also significantly increased under UV-B radiation. The integrative data analysis showed that UVR8-mediated signaling, jasmonate signaling, flavonoid biosynthesis pathway and DNA repair system might contribute to L. pyriforme acclimating to UV-B radiation. Therefore, these findings present a novel knowledge for understanding the adaption of Antarctic moss to polar environments and provide a foundation for assessing the impact of global climate change on Antarctic land plants. [ABSTRACT FROM AUTHOR]

Bryophytes are the dominant vegetation in the Antarctic continent. They have suffered more unpleasant ultraviolet radiation due to the Antarctic ozone layer destruction. However, it remains unclear about the molecular mechanism of Antarctic moss acclimation to UV-B light. Here, the transcriptomics and metabolomics approaches were conducted to uncover transcriptional and metabolic profiling of the Antarctic moss Leptobryum pyriforme under UV-B radiation. Totally, 67,290 unigenes with N50 length of 2,055 bp were assembled. Of them, 1,594 unigenes were significantly up-regulated and 3353 unigenes were markedly down-regulated under UV-B radiation. These differentially expressed genes (DEGs) involved in UV-B signaling, flavonoid biosynthesis, ROS scavenging, and DNA repair. In addition, a total of 531 metabolites were detected, while flavonoids and anthocyanins accounted for 10.36% of the total compounds. There were 49 upregulated metabolites and 41 downregulated metabolites under UV-B radiation. Flavonoids were the most significantly changed metabolites. qPCR analysis showed that UVR8-COP1-HY5 signaling pathway genes and photolyase genes (i.e., LpUVR3, LpPHR1, and LpDPL) were significantly up-regulated under UV-B light. In addition, the expression levels of JA signaling pathway-related genes (i.e., OPR and JAZ) and flavonoid biosynthesis-related genes were also significantly increased under UV-B radiation. The integrative data analysis showed that UVR8-mediated signaling, jasmonate signaling, flavonoid biosynthesis pathway and DNA repair system might contribute to L. pyriforme acclimating to UV-B radiation. Therefore, these findings present a novel knowledge for understanding the adaption of Antarctic moss to polar environments and provide a foundation for assessing the impact of global climate change on Antarctic land plants.

Ultraviolet-B (UVB) radiation generates reactive oxygen species (ROS), which damage DNA, proteins, and lipids in aquatic organisms, including fish. This study evaluated UVB-induced oxidative stress in several tissues of two marine teleosts, gilthead seabream (Sparus aurata) and European seabass (Dicentrarchus labrax). Juveniles of both species were exposed to four treatments simulating underwater UVB (no, low, moderate, and high UVB) doses for 6 weeks. Oxidative stress (the activities of several antioxidant enzymes (catalase, CAT; glutathione-S-transferase, GST; superoxide dismutase, SOD, and lipid peroxidation, LPO) were analyzed in the skin, liver, head kidney, gills, muscle, brain, intestine, spleen, and kidney samples obtained at increasing exposure times (3–43 days). UVB exposure induced significant lipid damage and antioxidant responses in several tissues, with the skin showing more pronounced effects in S. aurata than in D. labrax. In the skin of both species and in the liver of D. labrax, LPO levels significantly increased with increasing UVB intensity and exposure time. CAT activity was inhibited in both species (i.e., in liver, skin, head kidney, gills, spleen, and brain) of UVB exposed fish. SOD activity significantly decreased in the skin and head kidney of D. labrax; however, prolonged exposure time was required for significant effects in the skin and gills of S. aurata. GST activity reduced early in the skin of S. aurata, whereas significant effects were noted in the head kidney and brain at the end of experiment. An interactive effect between UVB intensity and exposure time was observed in the skin (seabream and seabass) and liver (seabass). Our results indicated that oxidative stress is induced in the skin as well as indirectly exposed tissues in S. aurata and D. labrax after UVB exposure at the subsurface of transparent seas.

• Omega-3 fatty acids suppress the increase in TEWL due to UV-B irradiation. • Omega-3 fatty acids mitigate damage to the granular layer caused by UV-B irradiation. • Omega-3 fatty acids regulate accelerated turnover due to UV-B irradiation. Mice fed a diet containing an adequate amount of ω-3 fatty acids (ω-3 Adq) or a deficient diet (ω-3 Def) were irradiated with ultraviolet-B (UV-B) and were measured daily changes in transepidermal water loss (TEWL). TEWL was significantly increased in ω-3 Def mice with repeated UV-B irradiation, but this increase was significantly reduced in ω-3 Adq mice. The epidermal layers revealed thickening of the spinous and basal layers induced by UV-B irradiation in both groups. Moreover, the ω-3 Def mice had a disturbed epidermal structure and a coarser stratum corneum. And the granule cell layer is significantly reduced, and abnormal layer formation (parakeratosis) occurred in the stratum corneum. These results suggest that continuous UV-B irradiation promotes epidermal turnover and leads to epidermal thickening, but ω-3 fatty acids protect the body from UV-B-induced stress. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the photoprotective potential of Viburnum grandiflorum (VG) against ultraviolet-B radiation-induced responses in HaCaT cells. The HaCaT cells were pretreated with VG prior ultraviolet-B (UVB)-radiation exposure and were further examined for lipid peroxidation, enzymatic antioxidant activity, % reactive oxygen species, DNA damage, mitochondrial membrane potential and for inflammatory, and apoptotic signaling markers such as tumor necrosis factor-alpha, nuclear factor kappa B, interleukin-1 (IL-1), IL-6, cyclooxygenase-2, p53, caspase-3/9, cytochrome-c, Bax, and Bcl-2. The VG pretreatment in UVB exposed cells shows significantly regulated both inflammatory as well as apoptotic signaling cascades. Our findings suggest that VG may be functional against UVB-induced photo-damages. [ABSTRACT FROM AUTHOR]

Background: Korean ginseng (Panax ginseng Meyer) is a traditional herbal medicine used worldwide today. Ginsenoside Rd (Rd), one of its main ginsenosides, has been ascertained to have various pharmacological efficacies including neuroprotective and anti-inflammatory activities. Objectives: This work assesses the antioxidant and protective potentials of Rd against ultraviolet (UV)-B-induced skin photooxidative stress in HaCaT keratinocytes. Materials and Methods: Cell viability was detected using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Intracellular reactive oxygen species (ROS) were measured using dichlorodihydrofluorescein diacetate. Promatrix metalloproteinase-2 (proMMP-2) activity and protein were detected using gelatin zymography and western analysis. Total glutathione (GSH) content and total superoxide dismutase (SOD) activity were spectrophotometrically determined. Results: Rd, at varying concentrations non-toxic to HaCaT keratinocytes, attenuated the UV-B-induced ROS generation. Rd at 5, 12, and 30 μM attenuated the UV-B-induced proMMP-2 gelatinolytic activities to 59.3% ± 9.5%, 41.3% ± 9.5%, and 13.1% ± 8.9%, respectively, of those of the non-treated control cells. It could also diminish the UV-B-induced proMMP-2 protein levels. Rd at 5, 12, and 30 μM augmented the UV-B-reduced total SOD activities to 1.6 ± 0.2-, 2.4 ± 0.3-, and 3.2 ± 0.2-fold of those of the non-treated control cells, respectively. Rd could up-regulate the UV-B-reduced total GSH. Conclusion: Rd has counteracting properties against elevated ROS and proMMP-2 and attenuated GSH and SOD under UV-B irradiation, implying that it possesses a protective activity against photoaging possibly through up-regulating antioxidant components. These findings suggest that Rd can be considered as a novel natural resource for anti-photoaging functional cosmetics. [ABSTRACT FROM AUTHOR]

The present study was focused to examine the combined effects of climate and ultraviolet-B radiation on conifer tree-ring density. Statistical methods were employed to extract tree responses in annual ring density and to identify functional relationship in trees when the level of ultraviolet-B radiation changes regardless of climate variations. In this study, the consideration was given to the series of total ozone content (instead of ultraviolet-B), tree-ring density, and De Martonne aridity index. After the correlation analysis, all trees were divided into two groups: 1) Trees whose correlation between tree ring density and UV-B values in April is significantly positive; 2) Trees whose correlation between tree ring density and aridity index values in March-September is significantly negative. Then, tree-ring series for the Swiss Alps in each group were generalized and decomposed into separate components: long period trends, ultraviolet-B and climatic signals. For the ultraviolet-B-responsive tree group in the period 1932-1974, the correlation coefficient between the density and ultraviolet-B was 0.55 at p

Ultraviolet-B radiation can result in deleterious effects on many plant growth processes. In clonal plants, resources and hormones are often shared between connected ramets to deal with various environments. However, little is known about whether and how clonal integration influences the ability of clonal plants to respond to UV-B radiation. In this paper, ramet pairs of Duchesnea indica were either connected by stolons or disconnected by stolon interruption. One of the ramet in the pair was exposed to elevated UV-B radiation. Water transport rate and several growth, photosynthetic and biochemical parameters were measured. When ramets were connected and exposed to heterogeneous UV-B radiation, the velocity of water transportation from the UV-B treated ramet to its connected sister ramet was markedly lower. Moreover, stolon connection resulted in an increase of biomass and ramet number in the UV-B stressed part of the clonal fragments at the expense of that in the UV-B unstressed part. In addition, the contents of chlorophylls and UV-B absorbing compounds were shared between connected ramets under heterogeneous UV-B radiation. Gas exchange and chlorophyll fluorescence parameters of the UV-B stressed ramets were impaired by supplemental UV-B radiation in Duchesnea indica. Clonal integration significantly reduced the stressful impact imposed by enhanced UV-B radiation at a cost to the whole clone. [ABSTRACT FROM AUTHOR]

Gradients in cuticle lightness of ectotherms have been demonstrated across latitudes and elevations. Three key hypotheses have been used to explain these macroecological patterns: the thermal melanism hypothesis (TMH), the melanism‐desiccation hypothesis (MDH) and the photo‐protection hypothesis (PPH). Yet the broad abiotic measures, such as temperature, humidity and UV‐B radiation, typically used to detect these ecogeographical patterns, are a poor indication of the microenvironment experienced by small, cursorial ectotherms like ants.We tested whether these macroecological hypotheses explaining cuticle lightness held at habitat and microclimatic level by using a vertical gradient within a tropical rainforest.We sampled 222 ant species in lowland, tropical rainforest across four vertical strata: subterranean, ground, understory and canopy. We recorded cuticle lightness, abundance and estimated body size for each species and calculated an assemblage‐weighted mean for cuticle lightness and body size for each vertical stratum. Abiotic variables (air temperature, vapour pressure deficit and UV‐B radiation) were recorded for each vertical stratum.We found that cuticle lightness of ant assemblages was vertically stratified: ant assemblages in the canopy and understory were twice as dark as assemblages in ground and subterranean strata. Cuticle lightness was not correlated with body size, and there was no support for the TMH. Rather, we attribute this cline in cuticle lightness to a combination of the MDH and the PPH.Our findings indicate that broad macroecological patterns can be detected at much smaller spatial scales and that microclimatic gradients can shape trait variation, specifically the cuticle lightness of ants. These results suggest that any changes to microclimate that occur due to land‐use change or climate warming could drive selection of ants based on cuticle colour, altering assemblage structure and potentially ecosystem functioning. [ABSTRACT FROM AUTHOR]

Prolonged exposure to harmful ultraviolet radiation (UVR) can induce many chronic or acute skin disorders in humans. To protect themselves, many people have started to apply cosmetic products containing UV-screening chemicals alone or together with physical sunblocks, mainly based on titanium–dioxide (TiO2) or zinc-oxide (ZnO2). However, it has now been shown that the use of chemical and physical sunblocks is not safe for long-term application, so searches for the novel, natural UV-screening compounds derived from plants or bacteria are gaining attention. Certain photosynthetic organisms such as algae and cyanobacteria have evolved to cope with exposure to UVR by producing mycosporine-like amino acids (MAAs). These are promising substitutes for chemical sunscreens containing commercially available sunblock filters. The use of biopolymers such as chitosan for joining MAAs together or with MAA-Np (nanoparticles) conjugates will provide stability to MAAs similar to the mixing of chemical and physical sunscreens. This review critically describes UV-induced skin damage, problems associated with the use of chemical and physical sunscreens, cyanobacteria as a source of MAAs, the abundance of MAAs and their biotechnological applications. We also narrate the effectiveness and application of MAAs and MAA conjugates on skin cell lines.

Abstract Ozone layer depletion leads to elevated ultraviolet-B (UV-B) radiation, which affects plant growth; however, little is known about the relationship between root growth and signaling molecules in roots. Therefore, in this work, simulated UV-B radiation was used to study the effects of elevated UV-B radiation on root growth of soybean seedlings and changes in the content of signaling molecules in roots. The results showed that compared with the control, the 2.63 kJ m−2 d−1 and 6.17 kJ m−2 d−1 elevated UV-B radiation treatments inhibited root growth, and root growth parameters (total root length, root surface area, root volume, average diameter, root tip number, and root dry weight) all decreased. For root signaling molecules, the content of nitric oxide, reactive oxygen species, abscisic acid, salicylic acid, and jasmonic acid increased, and the content of auxin, cytokinin, and gibberellin decreased. The above indices changed more significantly under the 6.17 kJ m−2 d−1 treatment. After withdrawal of the exposure, the above indices could be restored to a certain extent. These data indicated that UV-B radiation interfered with root growth by affecting the content of signaling molecules in roots, and the degree of the effects was related to the intensity of UV-B radiation. The results from this study provide a theoretical basis for studying the preliminary mechanism of elevated UV-B radiation on root growth and possible pathways that can mitigate UV-B radiation damage for root growth. One sentence summary The effects of elevated UV-B on root growth of soybean seedlings were regulated by signaling molecules, and the degree of the effects was related to the intensity of UV-B radiation. Graphical abstract fx1 Highlights • Study UV-B effects on root growth from perspective of chemical signaling molecules. • The UV-B effects on roots were mediated by chemical signaling molecules. • Chemical signaling molecules NO, ROS, and hormones, affect root growth. [ABSTRACT FROM AUTHOR]

The present study examines the impact of ultraviolet-B (UV-B) radiation stress on commercially significant microalga for biofuel application. Experimental alga Botryococcus braunii was treated under different doses of artificially enhanced UV-B radiation. The organism was treated under high dose rates of 1 and 5 Wm-2 with altered time durations of 15, 30, 45 and 60 min. It showed large variations in the growth characteristics analysed. The rate of whole-cell photosynthetic oxygen evolution showed steep drop in high dose compared to low dose-treated cultures. As a result, level of photosynthetic pigment chlorophyll a content decreased drastically while carotenoid level invariably increased. Consequently, the level of primary metabolites such as total carbohydrate, protein and lipid was drastically reduced under high dose while marginal decrement was observed at lowest dose of UV-B radiation. Overall, the impact of UV-B radiation on B. braunii led to a drop in protective mechanisms with associated decline in growth and cellular imbalance at high intensity studied. [ABSTRACT FROM AUTHOR]

Abstract Organisms suffer more harmful ultraviolet radiation in the Antarctica due to the ozone layer destruction. Bryophytes are the dominant flora in the Antarctic continent. However, the molecular mechanism of Antarctic moss adaptation to UV-B radiation remains unclear. In the research, the transcriptional profiling of the Antarctic moss Pohlia nutans under UV-B radiation was conducted by Illumina HiSeq2500 platform. Totally, 72,922 unigenes with N 50 length of 1434 bp were generated. Differential expression analysis demonstrated that 581 unigenes were markedly up-regulated and 249 unigenes were significantly down-regulated. The gene clustering analysis showed that these differentially expressed genes (DEGs) includes several transcription factors, photolyases, antioxidant enzymes, and flavonoid biosynthesis-related genes. Further analyses suggested that the content of malondialdehyde (MDA), the activities of several antioxidant enzymes (i.e., catalase, peroxidase, and glutathione reductase) were significantly enhanced upon UV-B treatment. Furthermore, the content of flavonoids and the gene expression levels of their synthesis-related enzymes were also markedly increased when plants were exposed to UV-B light. Therefore, these results suggested that the pathways of antioxidant enzymes, flavonoid synthesis and photolyases were the main defense systems that contributed to the adaption of Pohlia nutans to the enhanced UV-B radiation in Antarctica. Highlights • The transcriptome analysis of Pohlia nutans under UV-B treatment was performed using RNA-seq technology. • The expression of transcription factor, antioxidant enzyme, flavonoid-related enzyme were up-regulated after UV-B treatment. • The contents of MDA and flavonoids, and the activities of antioxidant enzymes were markedly increased after UV-B treatment. • This study reveals the important role of ROS-scavenging system in the process of Antarctic mosses adapting to UV-B radiation. [ABSTRACT FROM AUTHOR]

Abstract It has been suggested that accumulation of flavonoids could be a key step in development of plant tolerance to different environmental stresses. Moreover, it has been recognized that abiotic stresses such as drought and UV-B radiation (280–315 nm) induce phenolic compound accumulation, suggesting a role for these compounds in drought tolerance. The aim of the present study was to evaluate the effect of UV-B exposure on chili pepper (Capsicum annuum , cv. 'Coronel') plant performance, phenolic compound production, and gene expression associated with response to subsequent drought stress. Additionally, the phenotypic response to drought stress of these plants was studied. UV-B induced a reduction both in stem length, stem dry weight and number of floral primordia. The largest reduction in these variables was observed when combining UV-B and drought. UV-B-treated well-watered plants displayed fructification approximately 1 week earlier than non-UV-B-treated controls. Flavonoids measured epidermally in leaves significantly increased during UV-B treatment. Specifically, UV-B radiation significantly increased chlorogenic acid and apigenin 8-C-hexoside levels in leaves and a synergistic increase of luteolin 6-C-pentoside-8-C-hexoside was obtained by UV-B and subsequent drought stress. Gene expression of phenylalanine ammonia lyase (PAL) and chalcone synthase (CHS) genes also increased during UV-B treatments. On the other hand, expression of genes related to an oxidative response, such as mitochondrial Mn-superoxide dismutase (Mn- SOD) and peroxidase (POD) was not induced by UV-B. Drought stress in UV-B-treated plants induced mitochondrial Mn- SOD gene expression. Taken together, the UV-B treatment did not induce significant tolerance in plants towards drought stress under the conditions used. Highlights • UV-B reduced stem length, stem dry weight, and number of floral primordia in pepper. • Even larger reductions were observed when combining UV-B and drought. • Epidermal flavonoids in leaves increased during UV-B treatment. • UV-B increased chlorogenic acid and apigenin 8-C-hexoside levels in leaves. • UV-B increased phenylalanine ammonia lyase and chalcone synthase gene expression. [ABSTRACT FROM AUTHOR]

Abstract At temperate latitudes environmental factors such as irradiance, including ultraviolet-B radiation (UV-B, 280–315 nm), temperature and day length vary widely over the course of a year in a concerted way. In the present study physiological acclimation of photoprotection, growth and development of the model organism Arabidopsis thaliana were correlated to these strongly but gradually changing conditions in a one year field study. Plants were sown in the field avoiding any manipulation (and abrupt change) during their life. Developmental rate was strongly dependent on prevailing temperature. Moderate signs of light stress in form of photoinhibition at photosystem II were significantly related to solar irradiances while amount of DNA damage was low and not correlated to UV-B irradiance. Although all the markers were hypothesized to primarily react to radiation, multiple regression analysis showed at least a similarly strong influence of temperature as that of light. Especially for the classical UV screening compounds a positive correlation to UV-B radiation during the course of the year was absent, whereas there was a significant negative correlation between temperature and quercetin content. The sum of violaxanthin cycle pigments was correlated to both, irradiance and temperature, but with opposite sign. Epidermal UV-B transmittance was also much better related to air temperature than to UV-B irradiance. The data show that under natural conditions temperature has at least a similar importance for photoprotective acclimation and partially also for photosensitivity as solar irradiance. Highlights • Growth and phenology of Arabidopsis thaliana was followed over a year in the field. • UV absorbing pigments were significantly correlated to temperature but not to UV-B. • Only moderate photoinhibition and DNA damage were found. [ABSTRACT FROM AUTHOR]

Ultraviolet-B (UV-B) radiation (280−320 nm) may induce photobiological stress in plants, activate the plant defense system, and induce changes of metabolites. In our previous work, we found that between the two Astragalus varieties prescribed by the Chinese Pharmacopoeia, Astragalus mongholicus has better tolerance to UV-B. Thus, it is necessary to study the metabolic strategy of Astragalus under UV-B radiation further. In the present study, we used untargeted gas chromatography-mass spectrometry (GC-MS) and targeted liquid chromatography-mass spectrometry (LC-MS techniques) to investigate the profiles of primary and secondary metabolic. The profiles revealed the metabolic response of Astragalus to UV-B radiation. We then used real-time polymerase chain reaction (RT-PCR) to obtain the transcription level of relevant genes under UV-B radiation (UV-B supplemented in the field, λmax = 313 nm, 30 W, lamp-leaf distance = 60 cm, 40 min·day-1), which annotated the responsive mechanism of phenolic metabolism in roots. Our results indicated that supplemental UV-B radiation induced a stronger shift from carbon assimilation to carbon accumulation. The flux through the phenylpropanoids pathway increased due to the mobilization of carbon reserves. The response of metabolism was observed to be significantly tissue-specific upon the UV-B radiation treatment. Among phenolic compounds, C6C1 carbon compounds (phenolic acids in leaves) and C6C3C6 carbon compounds (flavones in leaves and isoflavones in roots) increased at the expense of C6C3 carbon compounds. Verification experiments show that the response of phenolics in roots to UV-B is activated by upregulation of relevant genes rather than phenylalanine. Overall, this study reveals the tissues-specific alteration and mechanism of primary and secondary metabolic strategy in response to UV-B radiation.

Sophora flavescens has been used in traditional medicine for the treatment of various diseases such as viral hepatitis, fever, cancer, and pain. It is known to contain many bioactive compounds including prenylated flavonoids such as kurarinone, sophoraflavanone G, kuraridine and isoxanthohumol. These flavonoids have been confirmed to have anti-inflammatory, α-glucosidase inhibitory and antioxidant performances. However, the protective activities against UV-induced skin damage of kushenol C from S. flavescens have not yet been elucidated. In this study, we explored the protective effect of kushenol C against the skin damage induced by UVB in mice. Our results showed that kushenol C treatment significantly recovered UVB-induced skin damage, the degradation of collagen, mast cell infiltration, together with epidermal hyperplasia in mice. Furthermore, the treatment of kushenol C remarkably suppressed the generation of pro-inflammatory mediators in the mice irradiated by UVB. More so, treatment with kushenol C suppressed the oxidative stress in mice irradiated by UVB. In conclusion, these results showed that kushenol C from S. flavescens has potentialities to treat skin injury via suppressing skin damage induced by UVB and oxidative stress., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

Nostoc flagelliforme is a pioneer organism in the desert and highly resistant to ultraviolet B (UV-B) radiation, while the involved adaptive mechanism has not been fully explored yet. To elucidate the responsive mechanism, two doses of UV-B radiation (low: 1 W/m2 and high: 5 W/m2) were irradiated for 6 h and 48 h, respectively, and their effects on global metabolism in N. flagelliforme were comprehensively investigated. In this study, we used iTRAQ-based proteomic approach to explore the proteomes of N. flagelliforme, and 151, 172, 124 and 148 differentially expressed proteins were identified under low and high UV-B doses for 6 h and 48 h, respectively. Functional classification analysis showed these proteins were mainly involved in photosynthesis, amino acid metabolism, antioxidant activity and carbohydrate metabolism. Further analysis revealed that UV-B imposed restrictions on primary metabolism including photosynthesis, Calvin cycle, and amino acid metabolism, and cells started defense mechanism through repair of DNA and protein damage, increasing antioxidant activity, and accumulating extracellular polysaccharides to minimize the damage. Moreover, high UV-B dose imposed more severe restrictions and activated stronger defense mechanism compared with low dose. The results would improve the understanding of molecular mechanisms of UV-B-stress adaption in N. flagelliforme. [ABSTRACT FROM AUTHOR]

The current study was focused to examine the combined effects of climate and ultraviolet-B radiation on conifer tree-ring density. Statistical methods were employed to extract tree responses in annual ring density and to identify functional relationship in trees when the level of ultraviolet-B radiation changes regardless of climate variations. In this study, the consideration was given to the series of total ozone content (instead of ultraviolet-B), tree-ring density, and De Martonne aridity index. After the correlation analysis, all trees were divided into two groups: 1) Trees whose correlation between tree ring density and UV-B values in April is significantly positive; 2) Trees whose correlation between tree-ring density and aridity index values in March-September is significantly negative. Then, tree-ring series for the Swiss Alps in each group were generalized and decomposed into separate components: long period trends, ultraviolet-B and climatic signals. For the ultraviolet-B-responsive tree group in the period 1932-1974, the correlation coefficient between the tree-ring density and ultraviolet-B was 0.55 at p <0.05. For the climate-responsive tree group the correlation coefficient between tree-ring density and aridity index was -0.51 at p < 0.05. Data mining diagrams showing the impact of atmospheric factors that affect the anatomic changes in the wood growing in mountain regions reveal that hormone can link the interaction of stem and crown. Generalized tree-ring density series may also be used to reconstruct past changes in ultraviolet-B and climate and to predict the conifer state in other mountain regions in the world. [ABSTRACT FROM AUTHOR]

Vitamin D plays a central role in calcium homeostasis of most vertebrates, and is obtained in different species through diet, dermal synthesis, or a combination of both. The aim of this study was to determine the predominant routes of Vitamin D synthesis in three disparate species, brown kiwi (Apteryx mantelli), tuatara (Sphenodon punctatus), and New Zealand sea lions (Phocarctos hookeri). We surveyed plasma concentrations of 25-hydroxyvitamin D2 and D3, analysed environmental conditions and life history factors, and determined the ability of skin samples to synthesise Vitamin D3 on exposure to ultraviolet-B radiation. There was variation in the plasma/serum 25-hydroxyvitamin D3 concentrations between and within the species studied, with wild kiwi having the lowest concentrations and NZ sea lions the highest. Kiwi skin produced small but measurable amounts of Vitamin D3, while tuatara skin produced Vitamin D3 concentrations higher than that of kiwi. New Zealand sea lion skin produced the highest amount of Vitamin D3 and differed from the other two species in this study in that Vitamin D3 was present in skin before UV-B exposure. The results from this study show that all three species studied retained the ability to use both dietary and dermal sources of Vitamin D, although there was interspecies variation in the magnitude of dermal synthesis. Comparisons between these species show that there are differences in their Vitamin D pathways, but suggest that there are more factors contributing to these pathways than might be expected solely from life history characteristics. [ABSTRACT FROM AUTHOR]

We describe an efficient technology to obtain vitamin D 2 -enriched mushroom powder by exposing postharvest shiitake mushrooms (Lentinula edodes) to UV-B radiation. UV-B exposure took place in a self-designed semi-industrial facility with the required safety measures. The highest vitamin D 2 content (1000 IU g−1 DM) was found when a total UV-B dose of 24 kJ m−2 was distributed in two different moments of the process (75% on sliced fresh mushroom and the remaining 25% on the dry powder). Similar results were obtained in king oyster (Pleurotus eryngii) and Portobello button (Agaricus brunnescens) mushrooms, indicating that the developed technology could generally be used to produce vitamin D 2 supplements from mushrooms. In addition, the same method increased the vitamin D 2 content in shiitake by-products, which could be used for animal feed. The microbiological, toxicological, and nutritional quality of the enriched mushroom preparations were confirmed to ensure a safe consumption. To determine the vitamin D bioavailability in humans, the enriched shiitake powder was encapsulated using 600 mg per capsule, which was equivalent to the minimum daily intake of vitamin D for adults. The capsules were ineffective in improving serum 25-hydroxyvitamin D status, but prevented an excessive decrease in this parameter due to winter conditions. • Three mushrooms were irradiated with UV-B to increase their vitamin D 2 contents. • The highest increase was obtained with 24 kJ m−2 UV-B on both fresh and dry material. • A safe semi-industrial facility was designed to apply UV-B radiation. • Vitamin-enriched shiitake powder was encapsulated to study bioavailability in humans. • Shiitake capsules prevented an excessive decrease of serum 25-hydroxyvitamin D level. [ABSTRACT FROM AUTHOR]

Ultraviolet-B (UV-B) is an effective elicitor that enhances bioactive ingredient biosynthesis in different plants. Chrysanthemum morifolium Ramat (C. morifolium) is a well-known herbal medicine and beverage material, which is cultivated in many Asian countries and regions. The C. morifolium inflorescences are the main accumulation sites for active ingredients, which include flavonoids and chlorogenic acid. However, the molecular mechanisms underlying UV-B-mediated bioactive ingredient biosynthesis in C. morifolium inflorescences remain largely unknown. High-throughput sequencing technologies have been applied to identify the messenger RNAs (mRNAs) and microRNAs (miRNAs) responsive to UV-B radiation in C. morifolium inflorescences. Many UV-B responsive genes are enriched in flavonoid, unsaturated fatty acid, phenylpropanoid, and carotenoid biosynthesis pathways. In this study, we identified 169 miRNAs belonging to 38 typical families were detected in our constructed libraries. In total, 1954 unigenes were predicted to be targets of 118 miRNAs. Six miRNAs, PC-5p-7136_1319 , PC-3p-78379_156 , ath-MIR414-p5_2ss2CT21AC , PC-3p-154888_69 , nta-miR171a_2ss8GT18GA and htu-miR403a were involved in the regulation of active ingredient biosynthesis by targeting 4CL-like 5/9 , CYP81E8 , UGT91D1 and UGT72B1 genes. Five miRNAs, PC-5p-79_56613 , ath-miR858a_L-1 , ath-MIR414-p5_2ss15AC18AT , ath-MIR414-p5_2ss2CT21AC , and aly-miR393a-5p were involved in regulation of flavonoid biosynthesis by targeting MYB-bHLH complex-related transcription factor genes. Our data provides a platform for identifying mRNAs and miRNAs involved in the UV-B-induced accumulation of bioactive ingredients in C. morifolium inflorescences. • In C. morifolium inflorescences, 169 miRNAs belonging to 38 typic families were detected in all libraries. • A total of 1954 unigenes were predicted to be the targets of 118 miRNAs. • Six miRNAs were involved in the regulation of active ingredient biosynthesis. • Data reveals the function of UV-B in bioactive ingredient biosynthesis of the Chrysanthemum species. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the protective effect of Diospyros lotus leaf extract (DLE) on UVB-induced skin damage in mice. UVB irradiation of mice skin incurred significant damage to mice skin; increased thiobarbituric acid-reactive substance level; decreased superoxide dismutase; and glutathione levels in mice skin tissues. More so, UVB irradiation led to collagen degradation and infiltration of mast cell and neutrophils into mice skin leading to inflammation. However, topical application of DLE significantly reversed these conditions with the result comparable to l-ascorbic acid. Myricitrin, gallic acid, astragalin, myricetin-3- O -glactosside, and myricetin through high-performance liquid chromatography analysis were further determined to be the primary active compounds in DLE. In conclusion, our study showed that DLE has potentials as local therapeutic materials against skin damage by inhibiting oxidative stress and UVB-induced skin damage. [ABSTRACT FROM AUTHOR]

Methane (CH) emissions from plants have been shown to increase with stress factors. However, the effects of multiple environmental stressors on CH emissions from various shoot parts have not been studied. Peas ( Pisum sativum L. cv. 237J Sundance) were used to determine CH emissions from the upper, middle and lower parts of shoot. Plants were grown in controlled-environment chambers under temperature regime of 22/18 or 28/24 °C (16-h light/8-h dark), ultraviolet-B (UVB) level of 0 or 5 kJ m day, and watering to field capacity (well-watered) or at wilting point (water-stressed). Methane emission, photosynthetic parameters ( A , net CO assimilation; E, transpiration; g , stomatal conductance; WUE, water use efficiency), chlorophyll fluorescence (ϕPSII, effective quantum yield of PSII; F / F , maximum quantum yield of PSII; qNP, non-photochemical quenching; qP, photochemical quenching), total chlorophyll and flavonoids were measured in shoots of 1-month-old plants. Higher temperatures and UVB increased CH emissions, which were higher from stem than leaf and from upper shoot than lower shoot. Lower leaves emitted more CH than upper leaves. Methane emissions were increased by higher temperatures with water stress from both shoot and stem, by UVB5 with water stress from stem, and by higher temperatures with UVB0 from leaf. Water stress decreased all photosynthetic parameters. Higher temperatures and UVB5 decreased WUE, whereas UVB5 increased E and g . UVB5 and water stress decreased ϕPSII, but water stress increased qNP. A , E, g , ϕPSII and chlorophyll were highest in the upper leaves. All the main factors decreased chlorophyll. UVB5 decreased flavonoids, which were lowest in the lower leaves. Methane emission from the stem had a positive correlation with E and g , but a negative correlation with WUE. Overall, stress factors increased CH emissions, which varied with shoot parts. [ABSTRACT FROM AUTHOR]

Humic substances have a tendency to form complexes with metal ions in aquatic medium, impacting the metal mobility, decreasing bioavailability and toxicity. Ultraviolet-B (UV-B) radiation exposure degrades the humic substance, changes their molecular weight distribution and their metal binding capacity in aquatic medium. In this study, we experimented the effect of UV-B radiation on the uranium complexed with fulvic acids and humic acids in a soft water system at different pH, uranium concentrations and radiant exposure. The concentration and distribution of uranium in a complexed form were investigated by asymmetrical flow field-flow fractionation coupled to multi detection technique (AsFlFFF-UV-ICP-MS). The major concentration of uranium present in complexes was primarily associated with average and higher molecular weight fulvic and humic acids components. The concentration of uranium in a complexed form increased with increasing fulvic and humic acid concentrations as well as pH of the solution. The higher molecular weight fraction of uranium was degraded due to the UV-B exposure, transforming about 50% of the uranium-dissolved organic carbon complexes into low molecular weight uranium species in complex form with organic ligands and/or free form. The result also suggests AsFlFFF-UV-ICP-MS to be an important separation and detection technique for understanding the interaction of radionuclides with dissolved organic matter, tracking size distribution changes during degradation of organic complexes for understanding mobility, bioavailability and ecosystem transfer of radionuclides as well as metals. [ABSTRACT FROM AUTHOR]