Pub Date : 2024-06-17DOI: 10.1007/s43630-024-00602-w
Masahiro Sugiura, Hideki Kandori
Photoisomerization is a key photochemical reaction in microbial and animal rhodopsins. It is well established that such photoisomerization is highly selective; all-trans to 13-cis, and 11-cis to all-trans forms in microbial and animal rhodopsins, respectively. Nevertheless, unusual photoisomerization pathways have been discovered recently in microbial rhodopsins. In an enzymerhodopsin NeoR, the all-trans chromophore is isomerized into the 7-cis form exclusively, which is stable at room temperature. Although, the 7-cis form is produced by illumination of retinal, formation of the 7-cis form was never reported for a protonated Schiff base of all-trans retinal in solution. Present HPLC analysis of retinal oximes prepared by hydroxylamine reaction revealed that all-trans and 7-cis forms cannot be separated from the syn peaks under the standard HPLC conditions, while it is possible by the analysis of the anti-peaks. Consequently, we found formation of the 7-cis form by the photoreaction of all-trans chromophore in solution, regardless of the protonation state of the Schiff base. Upon light absorption of all-trans protonated retinal Schiff base in solution, excited-state relaxation accompanies double-bond isomerization, producing 7-cis, 9-cis, 11-cis, or 13-cis form. In contrast, specific chromophore-protein interaction enforces selective isomerization into the 13-cis form in many microbial rhodopsins, but into 7-cis in NeoR.
{"title":"Photoisomerization pathway of the microbial rhodopsin chromophore in solution.","authors":"Masahiro Sugiura, Hideki Kandori","doi":"10.1007/s43630-024-00602-w","DOIUrl":"https://doi.org/10.1007/s43630-024-00602-w","url":null,"abstract":"<p><p>Photoisomerization is a key photochemical reaction in microbial and animal rhodopsins. It is well established that such photoisomerization is highly selective; all-trans to 13-cis, and 11-cis to all-trans forms in microbial and animal rhodopsins, respectively. Nevertheless, unusual photoisomerization pathways have been discovered recently in microbial rhodopsins. In an enzymerhodopsin NeoR, the all-trans chromophore is isomerized into the 7-cis form exclusively, which is stable at room temperature. Although, the 7-cis form is produced by illumination of retinal, formation of the 7-cis form was never reported for a protonated Schiff base of all-trans retinal in solution. Present HPLC analysis of retinal oximes prepared by hydroxylamine reaction revealed that all-trans and 7-cis forms cannot be separated from the syn peaks under the standard HPLC conditions, while it is possible by the analysis of the anti-peaks. Consequently, we found formation of the 7-cis form by the photoreaction of all-trans chromophore in solution, regardless of the protonation state of the Schiff base. Upon light absorption of all-trans protonated retinal Schiff base in solution, excited-state relaxation accompanies double-bond isomerization, producing 7-cis, 9-cis, 11-cis, or 13-cis form. In contrast, specific chromophore-protein interaction enforces selective isomerization into the 13-cis form in many microbial rhodopsins, but into 7-cis in NeoR.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141416731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-08DOI: 10.1007/s43630-024-00584-9
Florencia de la Rosa, Magdalena Pezzoni, Marleen De Troch, Cristina S Costa, Marcelo Hernando
Temperature up-shift and UV-A radiation effects on growth, lipid damage, fatty acid (FA) composition and expression of desaturase genes desA and desB were investigated in the cyanobacteria Microcystis aeruginosa. Although UV-A damaging effect has been well documented, reports on the interactive effects of UV radiation exposure and warming on cyanobacteria are scarce. Temperature and UV-A doses were selected based on the physiological responses previously obtained by studies with the same M. aeruginosa strain used in this study. Cells pre-grown at 26 °C were incubated at the same temperature or 29 °C and exposed to UV-A + PAR and only PAR for 9 days. Growth rate was significantly affected by UV-A radiation independently of the temperature throughout the experiment. High temperature produced lipid damage significantly higher throughout the experiment, decreasing at day 9 as compared to 26 °C. In addition, the cells grown at 29 °C under UV-A displayed a decrease in polyunsaturated FA (PUFA) levels, with ω3 PUFA being mostly affected at the end of exposure. Previously, we reported that UV-A-induced lipid damage affects differentially ω3 and ω6 PUFAs. We report that UV-A radiation leads to an upregulation of desA, possibly due to lipid damage. In addition, the temperature up-shift upregulates desA and desB regardless of the radiation. The lack of lipid damage for UV-A on ω3 could explain the lack of transcription induction of desB. The significant ω6 decrease at 26 °C in cells exposed to UV-A could be due to the lack of upregulation of desA.
研究了温度升高和紫外线辐射对蓝藻微囊藻(Microcystis aeruginosa)的生长、脂质损伤、脂肪酸(FA)组成以及去饱和酶基因 desA 和 desB 表达的影响。尽管紫外线-A 的破坏作用已被充分记录,但有关紫外线辐射和气候变暖对蓝藻的交互影响的报道却很少。温度和紫外线-A 剂量的选择是基于之前对本研究中使用的同一铜绿微囊藻菌株进行研究后得出的生理反应。在相同温度或 29 °C下培养在 26 °C下生长的细胞,并暴露于紫外线-A + PAR 或仅 PAR 下 9 天。在整个实验过程中,紫外线-A 辐射对生长率的影响与温度无关。在整个实验过程中,高温造成的脂质损伤明显增加,与 26 °C相比,第 9 天时脂质损伤有所减少。此外,在 29 °C紫外线-A条件下生长的细胞显示出多不饱和脂肪酸(PUFA)水平的下降,其中ω3 PUFA在暴露结束时受到的影响最大。此前,我们曾报道紫外线-A 诱导的脂质损伤对 ω3 和 ω6 PUFA 的影响不同。我们报告说,紫外线辐射导致 desA 上调,这可能是由于脂质损伤造成的。此外,无论辐射如何,温度上移都会上调 desA 和 desB。UV-A 对ω3 没有造成脂质损伤,这可以解释为什么没有诱导 desB 的转录。暴露于 UV-A 的细胞在 26 °C 时ω6 明显下降,这可能是由于 desA 没有上调。
{"title":"Effects of temperature up-shift and UV-A radiation on fatty acids content and expression of desaturase genes in cyanobacteria Microcystis aeruginosa: stress tolerance and acclimation responses.","authors":"Florencia de la Rosa, Magdalena Pezzoni, Marleen De Troch, Cristina S Costa, Marcelo Hernando","doi":"10.1007/s43630-024-00584-9","DOIUrl":"10.1007/s43630-024-00584-9","url":null,"abstract":"<p><p>Temperature up-shift and UV-A radiation effects on growth, lipid damage, fatty acid (FA) composition and expression of desaturase genes desA and desB were investigated in the cyanobacteria Microcystis aeruginosa. Although UV-A damaging effect has been well documented, reports on the interactive effects of UV radiation exposure and warming on cyanobacteria are scarce. Temperature and UV-A doses were selected based on the physiological responses previously obtained by studies with the same M. aeruginosa strain used in this study. Cells pre-grown at 26 °C were incubated at the same temperature or 29 °C and exposed to UV-A + PAR and only PAR for 9 days. Growth rate was significantly affected by UV-A radiation independently of the temperature throughout the experiment. High temperature produced lipid damage significantly higher throughout the experiment, decreasing at day 9 as compared to 26 °C. In addition, the cells grown at 29 °C under UV-A displayed a decrease in polyunsaturated FA (PUFA) levels, with ω3 PUFA being mostly affected at the end of exposure. Previously, we reported that UV-A-induced lipid damage affects differentially ω3 and ω6 PUFAs. We report that UV-A radiation leads to an upregulation of desA, possibly due to lipid damage. In addition, the temperature up-shift upregulates desA and desB regardless of the radiation. The lack of lipid damage for UV-A on ω3 could explain the lack of transcription induction of desB. The significant ω6 decrease at 26 °C in cells exposed to UV-A could be due to the lack of upregulation of desA.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140875276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-04DOI: 10.1007/s43630-024-00586-7
Rocío B Acosta, Edgardo N Durantini, Mariana B Spesia
The effect of photodynamic inactivation (PDI) sensitized by 5,10,15,20-tetra(4-N,N,N-trimethylammoniophenyl)porphyrin (TMAP4+) on different components of mono- and dual-species biofilms of Staphylococcus aureus and Escherichia coli was determined by different methods. First, the plate count technique showed that TMAP4+-PDI was more effective on S. aureus than E. coli biofilm. However, crystal violet staining revealed no significant differences between before and after PDI biofilms of both bacteria. On the other hand, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method indicated a reduction in viable cells as the light exposure time increases in both, mono- and dual-species biofilms. Furthermore, it was determined that as the irradiation time increases, the amount of extracellular polymeric substances present in the biofilms decreased. This effect was presented in both strains and in the mixed biofilm, being more evident in S. aureus mono-specie biofilm. Finally, scanning electron microscopy analysis showed a decrease in the number of cells forming the biofilm after photosensitization treatments. This information makes it possible to determine whether the photodynamic action is based on damage to metabolic activity, extracellular matrix and/or biomass, which may be useful in establishing a fully effective PDI protocol for the treatment of microorganisms growing as biofilms.
{"title":"Evaluation of quantification methods to determine photodynamic action on mono- and dual-species bacterial biofilms.","authors":"Rocío B Acosta, Edgardo N Durantini, Mariana B Spesia","doi":"10.1007/s43630-024-00586-7","DOIUrl":"10.1007/s43630-024-00586-7","url":null,"abstract":"<p><p>The effect of photodynamic inactivation (PDI) sensitized by 5,10,15,20-tetra(4-N,N,N-trimethylammoniophenyl)porphyrin (TMAP<sup>4+</sup>) on different components of mono- and dual-species biofilms of Staphylococcus aureus and Escherichia coli was determined by different methods. First, the plate count technique showed that TMAP<sup>4+</sup>-PDI was more effective on S. aureus than E. coli biofilm. However, crystal violet staining revealed no significant differences between before and after PDI biofilms of both bacteria. On the other hand, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method indicated a reduction in viable cells as the light exposure time increases in both, mono- and dual-species biofilms. Furthermore, it was determined that as the irradiation time increases, the amount of extracellular polymeric substances present in the biofilms decreased. This effect was presented in both strains and in the mixed biofilm, being more evident in S. aureus mono-specie biofilm. Finally, scanning electron microscopy analysis showed a decrease in the number of cells forming the biofilm after photosensitization treatments. This information makes it possible to determine whether the photodynamic action is based on damage to metabolic activity, extracellular matrix and/or biomass, which may be useful in establishing a fully effective PDI protocol for the treatment of microorganisms growing as biofilms.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140846380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-15DOI: 10.1007/s43630-024-00582-x
Julieta L Sacchetto, Leandro Fuentes Medina, Karina I Toledo, Silvana C Plem, Yamile Jalit, Eduardo A Gatica, Sandra Miskoski, José Natera, Cristian M O Lépori, Walter A Massad
Epoxiconazole (EPO) is classified as a persistent organic pollutant due to its ability to persist in the environment for prolonged periods. Its degradation is pivotal in mitigating its environmental impact. This investigation focuses on assessing the degradation of EPO using various methodologies, namely Fenton, photo-Fenton, solar photo-Fenton, and solar photolysis, conducted in both Milli-Q water and groundwater. These experiments encompassed evaluations at both the standard pH typically used in photo-Fenton reactions and the natural pH levels inherent to the respective aqueous environments. Additionally, EPO degradation products were analyzed after a 60-min reaction. Notably, in systems utilizing groundwater, the inclusion of additional iron was unnecessary, as the naturally occurring iron content in the groundwater facilitated the intended processes. Specifically, in Milli-Q water, solar photo-Fenton demonstrated an EPO degradation efficiency of 97%. Furthermore, the substitution of Milli-Q water with groundwater in Fenton-like processes did not significantly affect the efficacy of EPO degradation. These findings underscore the potential of solar photo-Fenton as an economically viable and environmentally sustainable strategy for EPO degradation.
{"title":"Epoxiconazole degradation in water samples: a comparative study of Fenton, photo-Fenton, solar photo-Fenton, and solar photolysis processes.","authors":"Julieta L Sacchetto, Leandro Fuentes Medina, Karina I Toledo, Silvana C Plem, Yamile Jalit, Eduardo A Gatica, Sandra Miskoski, José Natera, Cristian M O Lépori, Walter A Massad","doi":"10.1007/s43630-024-00582-x","DOIUrl":"10.1007/s43630-024-00582-x","url":null,"abstract":"<p><p>Epoxiconazole (EPO) is classified as a persistent organic pollutant due to its ability to persist in the environment for prolonged periods. Its degradation is pivotal in mitigating its environmental impact. This investigation focuses on assessing the degradation of EPO using various methodologies, namely Fenton, photo-Fenton, solar photo-Fenton, and solar photolysis, conducted in both Milli-Q water and groundwater. These experiments encompassed evaluations at both the standard pH typically used in photo-Fenton reactions and the natural pH levels inherent to the respective aqueous environments. Additionally, EPO degradation products were analyzed after a 60-min reaction. Notably, in systems utilizing groundwater, the inclusion of additional iron was unnecessary, as the naturally occurring iron content in the groundwater facilitated the intended processes. Specifically, in Milli-Q water, solar photo-Fenton demonstrated an EPO degradation efficiency of 97%. Furthermore, the substitution of Milli-Q water with groundwater in Fenton-like processes did not significantly affect the efficacy of EPO degradation. These findings underscore the potential of solar photo-Fenton as an economically viable and environmentally sustainable strategy for EPO degradation.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140924328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-03DOI: 10.1007/s43630-024-00580-z
Helena F Piedra, Manuel Plaza
In recent years, visible-light-induced organic transformations have taken a central role driving forward the progress of modern organic synthesis. These processes typically involve the transient generation of highly reactive radical intermediates, facilitating a diverse array of chemical reactions. Despite the abundance of synthetic strategies enabling the access of aryl and alkyl-centered radicals, the exploitation of photochemistry to generate highly reactive alkenyl radicals has remained notably underdeveloped. In this review, we present recent advancements in visible-light-induced transformations that proceed through the generation of alkenyl radicals from alkenyl-containing precursors, predominantly alkenyl halides, showcasing their application in various organic transformations.
{"title":"Advancements in visible-light-induced reactions via alkenyl radical intermediates.","authors":"Helena F Piedra, Manuel Plaza","doi":"10.1007/s43630-024-00580-z","DOIUrl":"10.1007/s43630-024-00580-z","url":null,"abstract":"<p><p>In recent years, visible-light-induced organic transformations have taken a central role driving forward the progress of modern organic synthesis. These processes typically involve the transient generation of highly reactive radical intermediates, facilitating a diverse array of chemical reactions. Despite the abundance of synthetic strategies enabling the access of aryl and alkyl-centered radicals, the exploitation of photochemistry to generate highly reactive alkenyl radicals has remained notably underdeveloped. In this review, we present recent advancements in visible-light-induced transformations that proceed through the generation of alkenyl radicals from alkenyl-containing precursors, predominantly alkenyl halides, showcasing their application in various organic transformations.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140846370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-14DOI: 10.1007/s43630-024-00578-7
Julianne C Nayar, Myriam Abboud, Katie M Dixon
Common therapeutics in relation to melanoma and non-melanoma cancers include the use of kinase inhibitors. The long-term benefits of kinases, however, are limited by development of drug resistance. An alternative approach for treatment would be to focus on transcription factors. Cyclic AMP-regulatory element-binding protein (CREB) is a transcription factor that is commonly overactivated or overexpressed in many different cancers including skin cancer. Ultraviolet radiation (UVR), one of the main causes of skin cancer, can activate CREB in both melanocytes and keratinocytes. In addition, CREB has been found to be activated in skin cancers. Considering the prominent role that CREB plays in skin cancers, the studies reviewed herein raise the possibility of CREB as a potential prognostic and diagnostic marker of skin cancer and a novel target for therapeutic intervention.
{"title":"Cyclic AMP-regulatory element-binding protein: a novel UV-targeted transcription factor in skin cancer.","authors":"Julianne C Nayar, Myriam Abboud, Katie M Dixon","doi":"10.1007/s43630-024-00578-7","DOIUrl":"10.1007/s43630-024-00578-7","url":null,"abstract":"<p><p>Common therapeutics in relation to melanoma and non-melanoma cancers include the use of kinase inhibitors. The long-term benefits of kinases, however, are limited by development of drug resistance. An alternative approach for treatment would be to focus on transcription factors. Cyclic AMP-regulatory element-binding protein (CREB) is a transcription factor that is commonly overactivated or overexpressed in many different cancers including skin cancer. Ultraviolet radiation (UVR), one of the main causes of skin cancer, can activate CREB in both melanocytes and keratinocytes. In addition, CREB has been found to be activated in skin cancers. Considering the prominent role that CREB plays in skin cancers, the studies reviewed herein raise the possibility of CREB as a potential prognostic and diagnostic marker of skin cancer and a novel target for therapeutic intervention.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140924327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-19DOI: 10.1007/s43630-024-00577-8
S Madronich, G H Bernhard, P J Neale, A Heikkilä, M P Sulbæk Andersen, A L Andrady, P J Aucamp, A F Bais, A T Banaszak, P J Barnes, J F Bornman, L S Bruckman, R Busquets, G Chiodo, D-P Häder, M L Hanson, S Hylander, M A K Jansen, G Lingham, R M Lucas, R Mackenzie Calderon, C Olsen, R Ossola, K K Pandey, I Petropavlovskikh, L E Revell, L E Rhodes, S A Robinson, T M Robson, K C Rose, T Schikowski, K R Solomon, B Sulzberger, T J Wallington, Q-W Wang, S-Å Wängberg, C C White, S R Wilson, L Zhu, R E Neale
The protection of Earth's stratospheric ozone (O3) is an ongoing process under the auspices of the universally ratified Montreal Protocol and its Amendments and adjustments. A critical part of this process is the assessment of the environmental issues related to changes in O3. The United Nations Environment Programme's Environmental Effects Assessment Panel provides annual scientific evaluations of some of the key issues arising in the recent collective knowledge base. This current update includes a comprehensive assessment of the incidence rates of skin cancer, cataract and other skin and eye diseases observed worldwide; the effects of UV radiation on tropospheric oxidants, and air and water quality; trends in breakdown products of fluorinated chemicals and recent information of their toxicity; and recent technological innovations of building materials for greater resistance to UV radiation. These issues span a wide range of topics, including both harmful and beneficial effects of exposure to UV radiation, and complex interactions with climate change. While the Montreal Protocol has succeeded in preventing large reductions in stratospheric O3, future changes may occur due to a number of natural and anthropogenic factors. Thus, frequent assessments of potential environmental impacts are essential to ensure that policies remain based on the best available scientific knowledge.
{"title":"Continuing benefits of the Montreal Protocol and protection of the stratospheric ozone layer for human health and the environment.","authors":"S Madronich, G H Bernhard, P J Neale, A Heikkilä, M P Sulbæk Andersen, A L Andrady, P J Aucamp, A F Bais, A T Banaszak, P J Barnes, J F Bornman, L S Bruckman, R Busquets, G Chiodo, D-P Häder, M L Hanson, S Hylander, M A K Jansen, G Lingham, R M Lucas, R Mackenzie Calderon, C Olsen, R Ossola, K K Pandey, I Petropavlovskikh, L E Revell, L E Rhodes, S A Robinson, T M Robson, K C Rose, T Schikowski, K R Solomon, B Sulzberger, T J Wallington, Q-W Wang, S-Å Wängberg, C C White, S R Wilson, L Zhu, R E Neale","doi":"10.1007/s43630-024-00577-8","DOIUrl":"10.1007/s43630-024-00577-8","url":null,"abstract":"<p><p>The protection of Earth's stratospheric ozone (O<sub>3</sub>) is an ongoing process under the auspices of the universally ratified Montreal Protocol and its Amendments and adjustments. A critical part of this process is the assessment of the environmental issues related to changes in O<sub>3</sub>. The United Nations Environment Programme's Environmental Effects Assessment Panel provides annual scientific evaluations of some of the key issues arising in the recent collective knowledge base. This current update includes a comprehensive assessment of the incidence rates of skin cancer, cataract and other skin and eye diseases observed worldwide; the effects of UV radiation on tropospheric oxidants, and air and water quality; trends in breakdown products of fluorinated chemicals and recent information of their toxicity; and recent technological innovations of building materials for greater resistance to UV radiation. These issues span a wide range of topics, including both harmful and beneficial effects of exposure to UV radiation, and complex interactions with climate change. While the Montreal Protocol has succeeded in preventing large reductions in stratospheric O<sub>3</sub>, future changes may occur due to a number of natural and anthropogenic factors. Thus, frequent assessments of potential environmental impacts are essential to ensure that policies remain based on the best available scientific knowledge.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141066669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Near-infrared two-photon absorption and excited state dynamics of a fluorescent diarylethene (fDAE) derivative were investigated by time-resolved absorption and fluorescence spectroscopies. Prescreening with quantum chemical calculation predicted that a derivative with methylthienyl groups (mt-fDAE) in the closed-ring isomer has a two-photon absorption cross-section larger than 1000 GM, which was experimentally verified by Z-scan measurements and excitation power dependence in transient absorption. Comparison of transient absorption spectra under one-photon and simultaneous two-photon excitation conditions revealed that the closed-ring isomer of mt-fDAE populated into higher excited states deactivates following three pathways on a timescale of ca. 200 fs: (i) the cycloreversion reaction more efficient than that by the one-photon process, (ii) internal conversion into the S1 state, and (iii) relaxation into a lower state (S1' state) different from the S1 state. Time-resolved fluorescence measurements demonstrated that this S1' state is relaxed to the S1 state with the large emission probability. These findings obtained in the present work contribute to extension of the ON-OFF switching capability of fDAE to the biological window and application to super-resolution fluorescence imaging in a two-photon manner.
{"title":"Near-infrared two-photon absorption and excited state dynamics of a fluorescent diarylethene derivative.","authors":"Hikaru Sotome, Tatsuhiro Nagasaka, Tatsuki Konishi, Kenji Kamada, Masakazu Morimoto, Masahiro Irie, Hiroshi Miyasaka","doi":"10.1007/s43630-024-00573-y","DOIUrl":"10.1007/s43630-024-00573-y","url":null,"abstract":"<p><p>Near-infrared two-photon absorption and excited state dynamics of a fluorescent diarylethene (fDAE) derivative were investigated by time-resolved absorption and fluorescence spectroscopies. Prescreening with quantum chemical calculation predicted that a derivative with methylthienyl groups (mt-fDAE) in the closed-ring isomer has a two-photon absorption cross-section larger than 1000 GM, which was experimentally verified by Z-scan measurements and excitation power dependence in transient absorption. Comparison of transient absorption spectra under one-photon and simultaneous two-photon excitation conditions revealed that the closed-ring isomer of mt-fDAE populated into higher excited states deactivates following three pathways on a timescale of ca. 200 fs: (i) the cycloreversion reaction more efficient than that by the one-photon process, (ii) internal conversion into the S<sub>1</sub> state, and (iii) relaxation into a lower state (S<sub>1</sub>' state) different from the S<sub>1</sub> state. Time-resolved fluorescence measurements demonstrated that this S<sub>1</sub>' state is relaxed to the S<sub>1</sub> state with the large emission probability. These findings obtained in the present work contribute to extension of the ON-OFF switching capability of fDAE to the biological window and application to super-resolution fluorescence imaging in a two-photon manner.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140875277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-05-13DOI: 10.1007/s43630-024-00583-w
Andreas Fellner, Nikolaus Bresgen, Michael Fefer, Jun Liu, Kristjan Plaetzer
Fruit flies spoil crops in agricultural settings. As conventional pesticides may generate negative off-target effects on humans or the environment, existing treatment methods need eco-friendly and safe alternatives. Photodynamic Inactivation (PDI) is based on the photosensitizer-mediated and light-induced overproduction of reactive oxygen species in targets. We here explore the potential of PDI for the control of fruit fly pests. Drosophila melanogaster serves as well-established model organism in this study. Two distinct experimental approaches are presented: the feed assay, in which fruit flies are provided with sodium magnesium chlorophyllin (Chl, approved as food additive E140) along with sucrose (3%) as their food, and the spray assay, where the photosensitizer is sprayed onto the insects. We show that PDI based on Chl can induce moribundity rates of Drosophila melanogaster of more than 99% with 5 mM Chl and LED illumination (395 nm, 8 h incubation in the dark, radiant exposure 78.9 J/cm2) with the feed assay. If the radiant exposure is doubled to 157.8 J/cm2, 88% of insects are killed by PDI based on 1 mM Chl. The photoactive compound is also effective if presented on strawberries without addition of sucrose with somewhat lower moribundity (71% at 5 mM Chl). Spraying Chl onto insects is less effective than feeding the photosensitizer: 5 mM Chl resulted in 79.5% moribundity (drug to light interval 8 h, radiant exposure 78.9 J/cm2), but if 5 h of sun light (532 J/cm2) and overnight (14 h) dark incubation is used for activation of Chl, more than 95% of insects are killed. As conclusion, Chl serves as effective photoinsecticide against Drosophila melanogaster if a drug to light interval of 8 h is maintained. Feeding the photoactive compound together with sucrose is more effective than spraying it onto insects and increasing the radiant exposure allows for lowering the photosensitizer concentration. Photodynamic Inactivation might therefore represent an eco-friendly addition to the farmers armamentarium against (semi-transparent) insects.
{"title":"Fly into the light: eliminating Drosophila melanogaster with chlorophyllin-based Photodynamic Inactivation.","authors":"Andreas Fellner, Nikolaus Bresgen, Michael Fefer, Jun Liu, Kristjan Plaetzer","doi":"10.1007/s43630-024-00583-w","DOIUrl":"10.1007/s43630-024-00583-w","url":null,"abstract":"<p><p>Fruit flies spoil crops in agricultural settings. As conventional pesticides may generate negative off-target effects on humans or the environment, existing treatment methods need eco-friendly and safe alternatives. Photodynamic Inactivation (PDI) is based on the photosensitizer-mediated and light-induced overproduction of reactive oxygen species in targets. We here explore the potential of PDI for the control of fruit fly pests. Drosophila melanogaster serves as well-established model organism in this study. Two distinct experimental approaches are presented: the feed assay, in which fruit flies are provided with sodium magnesium chlorophyllin (Chl, approved as food additive E140) along with sucrose (3%) as their food, and the spray assay, where the photosensitizer is sprayed onto the insects. We show that PDI based on Chl can induce moribundity rates of Drosophila melanogaster of more than 99% with 5 mM Chl and LED illumination (395 nm, 8 h incubation in the dark, radiant exposure 78.9 J/cm<sup>2</sup>) with the feed assay. If the radiant exposure is doubled to 157.8 J/cm<sup>2</sup>, 88% of insects are killed by PDI based on 1 mM Chl. The photoactive compound is also effective if presented on strawberries without addition of sucrose with somewhat lower moribundity (71% at 5 mM Chl). Spraying Chl onto insects is less effective than feeding the photosensitizer: 5 mM Chl resulted in 79.5% moribundity (drug to light interval 8 h, radiant exposure 78.9 J/cm<sup>2</sup>), but if 5 h of sun light (532 J/cm<sup>2</sup>) and overnight (14 h) dark incubation is used for activation of Chl, more than 95% of insects are killed. As conclusion, Chl serves as effective photoinsecticide against Drosophila melanogaster if a drug to light interval of 8 h is maintained. Feeding the photoactive compound together with sucrose is more effective than spraying it onto insects and increasing the radiant exposure allows for lowering the photosensitizer concentration. Photodynamic Inactivation might therefore represent an eco-friendly addition to the farmers armamentarium against (semi-transparent) insects.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140910779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-06-01Epub Date: 2024-06-05DOI: 10.1007/s43630-024-00565-y
Li-Hao Liu, Xian-Zhao Shang, Jian-Hao Yuan, Yi-Ning Luo, Jia-Yi Wang, Xiao-Lei Xue, Nan Jiang, Kun-Peng Wang, Zhi-Qiang Hu
A novel cyclic chalcone fluorescent probe C-PN was synthesized to detect ONOO-. After reaction with peroxynitrite, the double bond of C-PN in the cyclic chalcone structure was disconnected, which caused the change of intramolecular charge transfer (ICT) effect, emitting blue fluorescence and quenching orange red fluorescence. Visible to the naked eye, the color of the probe solution changed. The probe showed low sensitivity (detection limit = 20.2 nm), short response time (less than 60 s) at low concentration of ONOO-, good visibility, and good selectivity and stability for ONOO-.
{"title":"A fluorescent probe based on cyclochalcone for detecting peroxynitrite.","authors":"Li-Hao Liu, Xian-Zhao Shang, Jian-Hao Yuan, Yi-Ning Luo, Jia-Yi Wang, Xiao-Lei Xue, Nan Jiang, Kun-Peng Wang, Zhi-Qiang Hu","doi":"10.1007/s43630-024-00565-y","DOIUrl":"10.1007/s43630-024-00565-y","url":null,"abstract":"<p><p>A novel cyclic chalcone fluorescent probe C-PN was synthesized to detect ONOO<sup>-</sup>. After reaction with peroxynitrite, the double bond of C-PN in the cyclic chalcone structure was disconnected, which caused the change of intramolecular charge transfer (ICT) effect, emitting blue fluorescence and quenching orange red fluorescence. Visible to the naked eye, the color of the probe solution changed. The probe showed low sensitivity (detection limit = 20.2 nm), short response time (less than 60 s) at low concentration of ONOO<sup>-</sup>, good visibility, and good selectivity and stability for ONOO<sup>-</sup>.</p>","PeriodicalId":98,"journal":{"name":"Photochemical & Photobiological Sciences","volume":null,"pages":null},"PeriodicalIF":3.1,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141260245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}