Photochemistry and Photobiology最新文献

Several home pesticides are organophosphorus compounds. These compounds inhibit the enzyme acetylcholinesterase, causing harmful effects on the health of biota. Through this research, the usefulness of Glycine max (soybean) and Cichorium intybus (chicory) plants as sentinels of organophosphorus compounds in the environment was successfully tested. Different concentrations of the insecticide chlorpyrifos were tried out. Damage to plants at the photosynthetic apparatus level was evaluated by measuring the high temporal resolution variable chlorophyll fluorescence (OJIP test). Several parameters derived from this test indicated a high level of damage in both species even at the mean dose recommended for use in the field. However, a few parameters did not consistently reflect damage in leaves. A drop in the values of the maximum fluorescence (F_M), the quantum yield of electron transport flux, transport between quinones A and B (ET₀/ABS) and the maximal quantum yield of PSII (TR₀/ABS) could alert us about the presence of organophosphates in the environment. An increase in the dissipated energy flux per reaction center (DI₀/RC) values was also observed. The species showed different sensitivities, with soybean plants being the most sensitive. The OJIP transient thus becomes a valuable rapid, non-destructive tool for biomonitoring this class of pesticides in the environment.

Photo-biocatalyst coupled systems offer a promising approach for converting solar energy into valuable fuels. The bio-integrated photocatalytic system sets a research benchmark by utilizing green energy for formic acid production, reducing CO₂ emissions, and enhancing selectivity through bio-enzyme incorporation. This bio-photocatalytic are promising solutions for environmental remediation and energy production. This research reports the synthesis and application of a novel metal-free, nitrogen-enriched graphene composite photocatalyst (N_enGCTPP) for artificial photosynthesis. N_enGCTPP was synthesized by covalently coupling tetraphenyl porphyrin tetracarboxylic acid (TPP) with N-doped graphene via a polycondensation pathway. The photogenerated charge separation then facilitates the regeneration of enzymatically active coenzymes (NADH) for formic acid production catalyzed by formate dehydrogenase. The photocatalyst exhibited remarkable performance in photocatalytic regeneration of the coenzyme NADH from NAD⁺ with a high yield of 41.80%, as well as photocatalytic production of formic acid (HCO₂H) as a solar fuel from CO₂ with a yield of 99.12 μM. This innovative artificial photosynthetic system demonstrates an affordable, highly efficient, and selective approach for converting carbon dioxide into valuable solar fuels and regenerating NADH, addressing environmental concerns and contributing to sustainable energy solutions.

Plants may be a source of protective compounds that inhibit injuries caused by overexposure to solar radiation. Present work evaluated the protective effects of a phytochemical mixture based on Posoqueria latifolia extract + Kaempferol against ultraviolet-induced radiation DNA damage in human fibroblasts and mice skin. Cytotoxicity, genotoxicity, and antigenotoxicity of P. latifolia flower extract, Kaempferol, and the mixture of both were studied in MRC5 human fibroblasts using Trypan blue exclusion and Comet assays. Kinetics of DNA damage repair post irradiation, in the presence and absence of the phytochemicals, were also evaluated. The inhibition of UVB-induced erythema and cyclobutene pyrimidine dimers (CPD) by the phytochemicals and the mixture were also investigated in mice skin. We showed that the P. latifolia flower extract, Kaempferol, and the mixture inhibited UVB-induced DNA damage and increased DNA repair mechanisms in human fibroblasts. In addition, these phytochemicals inhibited the UVB-induced erythema and CPD in mice skin. The potential of the studied phytochemicals in human photoprotection was discussed.

While aging inevitably changes our skin, this complex biological process involves much more than just getting older. As the body's largest organ, the skin constantly safeguards us from harmful environmental pathogens and plays a key role in overall well-being. This study investigated the development and evaluation of a nanogel containing Rosa damascena essential oil for its potential anti-aging properties. The nanogel was prepared from a primary nanoemulsion with a particle size of 86 ± 4 nm. Antioxidant activity, measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, was found to be 76% ± 3%. Furthermore, the nanogel demonstrated superior anti-collagenase and anti-elastase activities (60% ± 2% and 51% ± 0.1%, respectively) compared to the essential oil alone. The antibacterial efficacy of the nanogel was tested against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, revealing potent inhibitory effects. To simulate the aging process, rats were subjected to UVB irradiation on both legs 4 days a week before or after treatment. In vivo studies conducted on mice showed that the nanogel effectively reduced the formation of deep wrinkles in treated groups compared to pretreated ones. These findings suggest that the introduced nanogel, with its antioxidant and antimicrobial properties, holds promise as a natural therapeutic approach for wrinkle treatment.

Virus-laden aerosols play a substantial role in the spread of numerous infectious diseases, particularly in enclosed indoor settings. Ultraviolet-C (UVC) disinfection is known to be a highly efficient method for disinfecting pathogenic airborne viruses. Recent recommendations suggest using far-UVC radiation (222 nm) emitted by KrCl* (krypton-chloride) excimer lamps to disinfect high-risk public spaces due to lower exposure risks than low-pressure (LP) mercury lamps (254 nm). This study experimentally explored the comparative effectiveness of far-UVC (222 nm) and germicidal UVC (254 nm) in inactivating virus-laden aerosols of different protective vector media in an air disinfection chamber. The UVC inactivation performances of individual filtered KrCl* excimer lamp and LP mercury lamp were determined for inactivating the bacteriophages, MS2 (icosahedral and non-enveloped ssRNA virus) and Phi6 (spherical and enveloped dsRNA virus) aerosolized from artificial human saliva or sodium chloride and magnesium sulfate (SM) buffer as a vector media. Disinfection efficacy of filtered KrCl* excimer lamp (222 nm) and LP mercury lamp (254 nm) were evaluated for highly concentrated viral aerosols, which replicate those exhaled from infected individuals and remain suspended in air or deposited on surfaces as fomites. Our results show that using individual filtered KrCl* excimer lamp (222 nm) and LP mercury lamp (254 nm) could greatly accelerate the inactivation of the viral bioaerosols formed from artificial human saliva and SM buffer. In the case of 222 nm exposure, Phi6 exhibited significantly more susceptibility in artificial human saliva than in SM buffer whereas MS2 showed comparable vulnerability in both artificial human saliva and SM buffer. However, in the case of 254 nm exposure, both Phi6 and MS2 demonstrated significantly greater susceptibility in artificial human saliva than in SM buffer. This study offers valuable insights and improves our understanding of the influence of different vector media on UVC disinfection of exhaled virus-laden aerosols in indoor environments. These findings can guide the deployment of UVC devices which could greatly contribute to mitigating the transmission of exhaled bioaerosols in public settings.

A heterogeneous photocatalyst based on copper-modified titanium dioxide nanoparticles has been prepared and characterized. Copper-modified nano-titanium dioxide (Nano-TiO₂@CuO) is an efficient photocatalyst for the synthesis of furan-3-carboxylate derivatives through a radical addition-polar cyclization of β-ketoester derivatives and allyl chloride under the irradiation of blue light. Copper-modified titanium dioxide nanoparticles 20% which show titanium dioxide-copper cooperativity show a significantly better performance with respect to turnover numbers (number of product molecules per catalyst molecule = efficiency). The Nano-TiO₂@CuO catalyst is stable and can be reused multiple times without a significant change in activity. The particle sizes varied in the range of 25-80 nm. High yields of product, environmentally friendly, cost-effective method, and easy work-up are advantages of the present method. All synthesized compounds were characterized by NMR and FT-IR spectroscopy.

Climate change involves the induction of heat and solar ultraviolet (UV) radiation, which profoundly affects sustainable crop production. Increasing solar UV radiation negatively impacts the photosynthetic apparatus, plant-associated organisms, and plant health. The present study aimed to comprehensively assess methylotrophic bacteria to alleviate heat and UV radiation in Vigna radiata L. under pot studies and field conditions. Under normal and UVB stress conditions, inoculation of methylotrophs significantly enhanced seed germination (72.55%-96.70% (normal) and 51.67%-65.33% (stressed)) and improved plant growth parameters, total chlorophyll (25.80-48.16 mg/g (normal) and 9.13-27.88 mg/g (stressed)), and carotenoid (569.1-1067.1 μg/g (normal) and 287.8-903.4 μg/g (stressed)) contents. A similar enhancement in antioxidant properties such as superoxide dismutase (1-5 fold), peroxidase (1-9 fold), phenylalanine ammonia lyase (1-4 fold), and proline content (1-5 fold) was observed in response to UVB radiation and heat stress under pot studies. A community-level physiological profile (CLPP) study of leaf samples revealed enhanced AWCD in methylotrophs treated plants compared to the UVB-exposed controls. Furthermore, field studies in summer conditions confirmed that inoculation with methylotrophs had a positive effect on V. radiata growth and physiology. The methylotrophs inoculation increased pod formation (25.44-32.78 and 15.56-32.00) and yield (109.81-238.63 and 71.88-216.29 q/ha) under UV cut-off sheet covered and non-covered conditions, respectively. This study demonstrated the potential of methylotrophs to mitigate heat and solar (UV) radiation in plants and provide sustainable strategies for agriculture and the environment.

Recently (Photochem Photobiol. 2023;100:1277-1289. doi:10.1111/php.13898), we described the anti-Kasha effect in tribenzo-6H-1,4-diazepinoporphyrazins with C_2v symmetry, where the ultrafast spin changes successfully compete with the internal conversion. In this study, we show the presence of this effect in 2 (3),9 (10),16(17),23(24)-tetra-tert-butyl-29H,31H-phthalocyanine (1) and 1,4-di-[2-(2-methoxyethoxy)ethoxy]-29H,31H-phthalocyanine (2), which also possess reduced molecular symmetry and do not bear 6H-1,4-diazepine fragments. The anti-Kasha effect in 1 and 2 supplemented by Mg(II) tribenzo-6H-1,4-diazepinoporphyrazinates 3 and 4 exhibits a close-to-linear dependence on energy gap value between the zero vibrational levels of two lowest singlet excited states S₁ ⁰ and S₂ ⁰ (these states are degenerate in D_4h symmetry) and enhances with increase. The theoretical kinetic model of excited state dynamics, which takes into account the observed effects and follows Fermi's golden rule, predicts the presence of an additional excited state with enhanced spin-orbit coupling compared to S₁ ⁰, S₂ ⁰ and the corresponding triplet states, which is not predicted by TDDFT calculations in the Born-Oppenheimer approximation. The combination of the above indicates that the key role in the observed anti-Kasha effect and the mechanism of dissipation of the excited state in porphyrazines and their analogs is played by vibronic excited states, which requires theoretical research methods beyond the Born-Oppenheimer approximation.

Skin serves as our outermost barrier, protecting our bodies from various environmental damages. Increasing research has revealed that UVB is a primary factor for extrinsic aging. This study explored the role of a novel microcapsule composite Spherulites Peony Superior Retinol (SPSR) on skin damage induced by UVB. SPSR exhibited a capacity to eliminate UVB-induced ROS. By measurement of cyclobutane pyrimidine dimers (CPD) and comet assay, the results implied that SPSR mitigates DNA damage from oxidative damage caused by UVB. In addition, UVB radiation typically leads to an increase in inflammatory factors within the skin. Decreased gene expressions of interleukin-1α and TNF-α have been observed in HaCaT cells. Moreover, a decreased gene expression of extracellular matrix (ECM)-related protein, including fibronectin (FN1), Col1A1, and Col3A1 caused by UVB was mitigated by SPSR. Furthermore, the clinical trials with 30 volunteers confirmed the significant relief and antiwrinkle effects of the cosmetic formulation containing 0.1% SPSR. These findings implied the promising potential of SPSR as a comprehensive solution for combating the detrimental effects of UVB exposure and maintaining skin health.

We report the occurrence of acquired tumor cell resistance to 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) in combination with ABCG2 inhibition. ALA-PDT in combination with either an ABCG2 tool inhibitor Ko143 or a repurposed clinically-relevant ABCG2 inhibitor lapatinib was highly effective in eradicating the H4 human glioma cells, resulting in minimal cell survival after treatment. However, after seven rounds of repeated treatments with light dose escalation, the resultant tumor cells became resistant to the combination therapy. The resistant sublines and the parental cell line showed similar ABCG2 activities and protein levels, indicating that it was not ABCG2 that caused the resistance. They also exhibited similar responses to PpIX-PDT and mTOR inhibitor AZD2014, suggesting that alterations in PDT sensitivity and mTOR pathway had little contribution to the development of resistance phenotype. By determining the intracellular and extracellular PpIX levels, the activities and protein levels of heme biosynthesis enzymes, we found that porphobilinogen deaminase (PBGD) activity and protein level were significantly reduced in the resistant sublines, causing resistance to PDT by substantially reducing PpIX biosynthesis. A novel acquired resistance mechanism to ALA-PDT with ABCG2 inhibition has been uncovered.