Blue Light Radiation Research Articles

Night Blue-light Radiation Enhances Anthocyanin Production in Purple Paprika ‘Tequila’ by Increasing Its Structural-gene Expression during Fruit Growth

Night Blue-light Radiation Enhances Anthocyanin Production in Purple Paprika ‘Tequila’ by Increasing Its Structural-gene Expression during Fruit Growth

Removal of Nitrogen and Phosphorus in Low Polluted Wastewater by Aquatic Plants: Impact of Monochromatic Light Radiation

Plant absorption via aquatic plants is vital for the deep purification of treated wastewater. This study aimed to determine the removal efficiencies of nitrogen and phosphorus for different aquatic plants and the effect of monochromatic light as compared to white light. Five plants (i.e., Iris pseudacorus, Oenanthe javanica, Zantedeschia aethiopica, Ipomoea aquatica Forssk. and Sagittaria trifolia) were cultured in prepared wastewater and radiated by white, red, green and blue LED lamps with 8 h radiation per day, respectively. After 4 d of cultivation, the O. javanica and S. trifolia exhibited relatively better growth status and higher TP removal rates (90%). The blue light radiation played a key role in the TP uptake of the tested plants. The N removal rates of plants were relatively lower (10–40%), limited by the low COD content. The S. trifolia exhibited the highest efficiency, and red light promoted the removal of TN and NO3−-N, whereas NH4+-N removal was driven by blue light radiation. So, O. javanica and S. trifolia coupled with blue and red lamps as supplementary light were suggested for the deep purification of municipal treated wastewater. The effect of intensity and ratio of monochromatic lights could be a direction for further research.

Riboflavin-induced photo-ATRP electrochemical strategy for detection of biomarker trypsin

The detection of trypsin and its inhibitors is important for both clinical diagnosis and disease treatment. Abnormal trypsin activity affects pancreatic function and leads to corresponding pathological changes in the body. Therefore, the study presented a riboflavin-induced photo-ATRP electrochemical assay of trypsin activity and its inhibitor, including detection of trypsin activity in real urine samples. Experiments were performed on indium tin oxide (ITO) electrodes modified with sulfhydryl groups of 3-mercaptopropionic acid, and target trypsin-specific cleavage of BSA-Au nanocluster (BSA-Au NCs) was followed by the modification of Au NCs to the electrodes using Au–S. The Au NCs immobilized monodeoxy-monomercapto-β-cyclodextrin@adamantan-2-amine (SH-β-CD@2-NH2-Ada) host-guest inclusion complexes to the electrode surfaces via Au–S. In a two-component photo-initiator system consisting of riboflavin as an initiator and ascorbic acid (AA) as a mild reducing agent under mild blue light radiation, a large number of electroactive substances were grafted onto the electrode surface to generate electrochemical signals. In addition, we have successfully realized the detection of clinical drug inhibitors of trypsin. The detection limit of the system is as low as 0.0024 ng/mL, which much littler than the average standard of trypsin in the patient's urine or serum. It's worth noting that this work will provide researchers with a different route to design electrochemical sensors based on non-covalent recognition strategies.

Deciphering the Effects of Different Types of Sunlight Radiation on Skin Function: A Review

Sunlight radiation is a fundamental component of our daily lives. Specifically, blue light as well as UV light appear to play a role in the development of oxidative stress, DNA damage, photoaging, and pigmentation through the chromophores in skin tissues. However, several skin problems like psoriasis, eczema, and atopic dermatitis can be avoided with short-duration exposures to low-energy blue light radiation or UV radiation. In addition, exploring the effects of blue light as well as UV radiation on skin is quite essential for the development of minimally invasive antiaging strategies and for the design of innovative cosmetic formulations in modern aesthetics and cosmetology. Thus, in this review, we present the advantages as well as the disadvantages of light radiation, with a special focus on blue light and UV radiation activity on the human skin. We also discuss the molecular action of blue light and UV radiation on human skin. Other types of light radiation are included to holistically approach the effect of light on human skin.

The wavelength dependence of oxygen-evolving complex inactivation in Zosteramarina

Zostera marina, a critical keystone marine angiosperm species in coastal seagrass meadows, possesses a photosensitive oxygen evolving complex (OEC). In harsh environments, the photoinactivation of the Z. marina OEC may lead to population declines. However, the factors underlying this photosensitivity remain unclear. Therefore, this study was undertaken to elucidate the elements contributing to Z. marina OEC photosensitivity. Our results demonstrated a gradual decrease in photosystem II performance towards shorter wavelengths, especially blue light and ultraviolet radiation. This phenomenon was characterized by a reduction in Fv/Fm and the rate of O2 evolution, as well as increased fluorescence at 0.3 ms on the OJIP curve. Furthermore, exposure to shorter light wavelengths and longer exposure durations significantly reduced the relative abundance of the OEC peripheral proteins, indicating OEC inactivation. Analyses of light-screening substances revealed that carotenoids, which increased most notably under 420 nm light, might primarily serve as thermal dissipators instead of efficient light filters. In contrast, anthocyanins reacted least to short-wavelength light, in terms of changes to both their content and the expression of genes related to their biosynthesis. Additionally, the levels of aromatically acylated anthocyanins remained consistent across blue-, white-, and red-light treatments. These findings suggest that OEC photoinactivation in Z. marina may be linked to inadequate protection against short-wavelength light, a consequence of insufficient synthesis and aromatic acylation modification of anthocyanins.

Responses of microorganisms to different wavelengths of light radiation during green waste composting

Light radiation can degrade recalcitrant materials like lignocelluloses in litter and serve as a physical condition to accelerate green waste (GW) decomposition, but few studies have considered the microbial effects of light wavelength on GW composting. This study innovatively investigated the effects of different wavelengths of light radiation, including full-spectrum, no blue light, no UV, no UV-A, no UV-B, and dark conditions, on accelerating the GW composting process. Especially, the study explored the dynamic changes in the degradation of lignocelluloses and evaluated the responses of microorganisms throughout the composting process under different light radiation wavelengths. No blue light (where radiation between 400 and 500 nm was blocked by the film) yielded the highest-quality compost within 40 days. In comparison to the dark (control), no blue light exhibited an elevated composting temperature (56.7 °C), an extended thermophilic phase (6 days), and increased degradation rates of lignin, cellulose, and hemicellulose by 13 %, 15 %, and 12 %, respectively. This study revealed that during the composting mesophilic phase, bacterial diversity performed best under no blue light, while fungal diversity excelled under full-spectrum. In the thermophilic phase, microbial diversity exhibited optimal performance under full-spectrum. During the cooling phase, bacterial diversity was highest under no blue light, and fungal diversity excelled under no UV-A. During the mesophilic and cooling phases, the bacterial ACE index for no blue light exceeded that of the other light radiation wavelengths, with values of 418 and 494, respectively. Under no blue light, the Shannon index of microorganisms remained within the range of 2.0–4.8, demonstrating superior performance. Meanwhile, the relative abundances of lignin-degrading microorganisms (Flavobacterium, Acaulium, and Acremoniu) under no blue light has increased, demonstrating improved microbial community structures. Therefore, no blue light radiation offered a novel approach to expedite GW composting.

Antioxidant potential of chlorogenic acid in Age-Related eye diseases.

Oxidative stress is an important mechanism of aging, and in turn, aging can also aggravate oxidative stress, which leads to a vicious cycle. In the process of the brain converting light into visual signals, the eye is stimulated by harmful blue-light radiation directly. Thus, the eye is especially vulnerable to oxidative stress and becomes one of the organs most seriously involved during the aging process. Cataracts, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), and dry eye are inextricably linked to the aging process and oxidative stress. Chlorogenic acid (CGA) has been demonstrated to have antioxidant and anti-inflammatory activities, and its validity has been established experimentally in numerous fields, including cardiovascular disease, metabolic disorders, cancers, and other chronic diseases. There has previously been evidence of CGA's therapeutic effect in the field of ophthalmopathy. Considering that many ophthalmic drugs lead to systemic side effects, CGA may act as a natural exogenous antioxidant for patients to take regularly, controlling their condition while minimizing side effects. In this paper, invitro and invivo studies of CGA in the treatment of age-related eye diseases are reviewed, and the prospects of CGA's antioxidant application for the eye are discussed. The aim of this review is to summarize the relevant knowledge and provide theoretical support for future research.

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

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

The potency of kitolod leaves (Hipobroma longiflora) as traditional medicine for conjunctivitis during the COVID-19 pandemic: a brief review

During the coronavirus disease 2019 (COVID-19) pandemic, most activities have transformed into digital ones, including computer usage. The digital screen on the computer has blue light radiation which can activate inflammatory cytokines of the eye surface and cause various disorders including includes conjunctivitis. Kitolod leaves (Hippobroma longiflora) have been used traditionally to treat conjunctivitis. This paper aimed to describe the potency of kitolod leaves for conjunctivitis. This is a narrative literature review using publications gathering from PubMed and Google Scholar published since 2013 with exclusion criteria were the animal studies. The keywords of COVID-19 pandemic, blue light, conjunctivitis, H. longiflora, traditional therapy were used. Boolean logic "AND" was used to find specific international scientific publications in PubMed. Forty selected publications were gathered, summarized and then narrated. The kitolod leaves contains bioactive substances i.e. flavonoids, alkaloids, and saponins which can inhibit S. aureus growth as the main cause of conjunctivitis. The mechanism of antibacterial of these bioactive substances through inhibition of nucleic acid synthesis, disruption of cytoplasmic membrane function, and inhibition of energy formation process. Kitolod leaves is potential to develop as traditional medicine for conjunctivitis. However, further studies are required to obtain the best standardized extract and to evaluate its clinical efficacy and safety.

MBE-grown Fe:Pd/ZnSe Schottky-barrier photodetector: Distinguishing blue + UV light levels among white light sources

Blue and ultraviolet radiation is well known to be associated with cataract formation and visual damage. Nowadays, children and teenagers are increasingly exposed to blue light and electromagnetic radiation with even shorter wavelength, which may cause damage to vision due to their frequent use of electronic display devices and participation in disco parties and concerts with illumination by UV light. We developed a Fe:Pd/ZnSe Schottky barrier photodetector that detects blue and UV light with excellent long-wavelength rejection power for green and red light of 4.24 and 5.65 orders, respectively. Its Schottky-barrier height and built-in potential are determined to be 2.48 and 1.17 eV, respectively. Together with the help of a lux meter, this simple and robust photodetector detects the blue light + UV content of different LED light bulbs with accuracy comparable to the much more sophisticated and expensive spectrometer. This compact and efficient blue + UV light detector can help us to increase the awareness of over-exposure to vision damaging radiation.

Awareness Regarding Occupational Hazards Among the Dental Students of a Medical College of Nepal

Introduction: Dental students, during their clinical and preclinical practices, are constantly exposed to a number of occupational hazards. Such exposures lead to various ailments and diseases. The study was done to assess the awareness regarding occupational hazards among dental students in College of Medical Sciences, Nepal. Methods: A questionnaire-based, descriptive cross-sectional study was conducted among the dental students from College of Medical Sciences, Nepal. Demographic details and awareness on different variables like bioaerosols, X-rays, blue light radiation, vibration, noise, posture, ergonomics, mercury vapour inhalation and percutaneous incidents, were assessed with the close-ended questions.Questionnaire was delivered to the participants in paper-printed forms. Data analysis was done using SPSS version 17. Chi-square tests were done to find the association between the variables to education and gender and the level of significance was set at p&lt;0.05. Results: The mean knowledge score for the male students was higher than that for the female students and the difference was statistically significant (p&lt;0.001). Fourth year students had the highest mean knowledge score (6.25±1.70) and second year students (2.71±2.43) had the lowest, and the scores were statistically significant (p&lt;0.001). More than two-third of the students (72.8%) did not know that vibration causes peripheral neuropathy; more than three-fifth of them (61.7%) didn’t know that noise induced hearing loss is possible at dental settings and; about three-fifth of them (59.3%) did not know that X-ray hazards can be mitigated by barrier methods and position distance rule. Conclusion: The awareness regarding the radiation hazards, vibration hazards and noise induced hazards seem to be limited among the dental students. The study suggests introducing specific intervention programs like occupational safety seminars, trainings or workshops, for the dental students, before the commencement of their practical classes.

Introducing Protein Homeostasis and Glycogen Synthesis as Two Targets of Blue Light Radiation in Lentinula edodes.

Introduction: There are documents about the biological effects of blue light radiation on different organisms. An understanding of the molecular mechanism of radiation effects on biological samples is an important event which has attracted researchers' attention. Determining the critical dysregulated proteins of Lentinula edodes following blue light radiation is the aim of this study. Methods: 22 differentially expressed proteins of L. edodes in response to 300 lux of blue light were extracted from the related literature. Experimental, text mining and co-expression connections between the queried proteins were assessed via the STRING database. The maps were compared and the critical proteins were identified. Results: Among the 21 queried proteins, six individuals including heat shock HSP70 protein, 20S proteasome subunit, 26S proteasome subunit P45, Aspartate aminotransferase, phosphopyruvate hydratase, and phosphoglucomutase were highlighted as the critical proteins in response to blue light radiation. Conclusion: The finding indicates that protein homeostasis and glycogen synthesis are affected by blue light radiation. Due to the critical roles of proteins as enzymes and structural elements in life maintenance and involvement of glycogen synthesis in energy consumption, blue light radiation can be considered as a life promotional agent in future investigations.

Understorey light quality affects leaf pigments and leaf phenology in different plant functional types.

Forest understorey plants receive most sunlight in springtime before canopy closure, and in autumn following leaf‐fall. We hypothesised that plant species must adjust their phenological and photoprotective strategies in response to large changes in the spectral composition of the sunlight they receive. Here, we identified how plant species growing in northern deciduous and evergreen forest understoreys differ in their response to blue light and ultraviolet (UV) radiation according to their functional strategy. We installed filters in a forest understorey in southern Finland, to create the following treatments attenuating: UV radiation below 350 nm, all UV radiation (< 400 nm), all blue light and UV radiation (< 500 nm), and a transparent control. In eight species, representing different functional strategies, we assessed leaf optical properties, phenology, and epidermal flavonoid contents over two years. Blue light accelerated leaf senescence in all species measured in the understorey, apart from Quercus robur seedlings, whereas UV radiation only accelerated leaf senescence in Acer platanoides seedlings. More light‐demanding species accumulated flavonols in response to seasonal changes in light quality compared to shade‐tolerant and wintergreen species and were particularly responsive to blue light. Reduction of blue and UV radiation under shade reveals an important role for microclimatic effects on autumn phenology and leaf photoprotection. An extension of canopy cover under climate change, and its associated suppression of understorey blue light and UV radiation, may delay leaf senescence for understorey species with an autumn niche.

Effects of UV–visible radiation on growth, photosynthesis, pigment accumulation and UV-absorbing compounds in the red macroalga Gracilaria cornea (Gracilariales, Rhodophyta)

Radiation induces different processes in photosynthetic organisms through photosynthetic pigments and photoreceptors. This study evaluated the performance of the red alga Gracilaria cornea cultivated under different radiation treatments. The objective was to identify responses associated with the treatments and mediated by photoreceptors. For this, G. cornea was exposed for 15 days to low fluence radiation of the ultraviolet (UV)-visible spectrum (red, green and blue light, and UV-A and UV-B radiation) combined with a high fluence radiation provided by a low-pressure sodium lamp (SOX), in order to saturate the photosynthesis. We measure the growth rate and other variables, such as photosynthesis estimated as chlorophyll a fluorescence, chlorophyll a, phycobiliproteins, carotenoids, mycosporine-like amino acids (MAAs), phenolic compounds, antioxidant capacity soluble proteins, and internal carbon and nitrogen content. The results showed that the UV radiation influenced the growth rates, as well as the accumulation of internal compounds (carotenoids: violaxanthin, antheraxanthin and zeaxanthin; MAA palythine; and phenolic compounds). As the treatments with UV radiation also had a peak of blue light, the presence of photoreceptors sensitive to these qualities of radiation (UV-A, UV-B and blue light) is suggested. In general, UV-A appears to induce some compounds without affecting growth, while UV-B seems to cause the accumulation of compounds at the expense of growth. The effect of light quality on growth and metabolism in G. cornea is compared to that in other species following similar experimental design.

Transcriptome Analysis Reveals Differences in Anthocyanin Accumulation in Cotton (Gossypium hirsutum L.) Induced by Red and Blue Light.

Many factors, including illumination, affect anthocyanin biosynthesis and accumulation in plants. light quality is the key factor affecting the process of photoinduced anthocyanin biosynthesis and accumulation. We observed that the red color of the Upland cotton accession Huiyuan with the R1 mutation turned to normal green color under light-emitting diodes (LEDs), which inspired us to investigate the effect of red and blue lights on the biosynthesis and accumulation of anthocyanins. We found that both red and blue lights elevated accumulation of anthocyanins. Comparative transcriptomic analyses, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and GSEA, revealed that genes differentially expressed under different light conditions were enriched with the pathways of circadian rhythm, phenylpropanoid biosynthesis, anthocyanin biosynthesis, and flavone and flavonol biosynthesis. Not surprisingly, all the major structural genes related to biosynthesis of anthocyanins, including the key regulatory MYB transcription factor (GhPAP1D) and anthocyanin transporter (GhGSTF12), were induced by red or blue light treatment. However, LARs and MATEs related to biosynthesis of proanthocyanidins were more significantly up-regulated by red light radiation than by blue light radiation. Vice versa, the accumulation of anthocyanins under red light was not as high as that under blue light. In addition, we demonstrated a potential role of GhHY5, a key regulator in plant circadian rhythms, in regulation of anthocyanin accumulation, which could be achieved via interaction with GhPAP1D. Together, these results indicate different effect of red and blue lights on biosynthesis and accumulation of anthocyanins and a potential module including GhHY5 and GhPAP1D in regulation of anthocyanin accumulation in cotton. These results also suggest that the substrates responsible the synthesis of anthocyanins under blue light is diverted to biosynthesis of proanthocyanidin under red light.

EGR1 Is a Critical Gene in Response of Human Keratinocyte to Blue Light Radiation.

Introduction: Investigating the molecular mechanism of cellular response to light radiation has attracted many researchers' attention. In the present study, the critically affected gene by 7.5 min blue light radiation in human keratinocytes was investigated via network analysis. Methods: Gene expression profiles of human keratinocytes exposed to 7.5 min blue light radiation plus controls were extracted from Gene Expression Omnibus (GEO). The significant dysregulated genes plus 100 first neighbors were investigated by Cytoscape software and its applications. The central nodes of the network based on four centrality parameters were determined and discussed. Results: Among 6 significant dysregulated genes, 4 individuals were recognized by the STRING database. The network was constructed by using the 4 queried genes and 100 first neighbors. EGR1, STAT1, and ISG15 were identified as central nodes; however, the prominent role of EGR1 was highlighted. Conclusion: EGR1 appeared as a critically affected gene after blue light irradiation. It seems that this upregulated gene is responsible for protecting human keratinocytes against stress and cancer. Therefore, the application of blue light may be accompanied by antistress effects in the human body.

Review of Low-Frequency Noise Properties of High-Power White LEDs during Long-Term Aging.

Low-frequency noise investigation is a highly sensitive and very informative method for characterization of white nitride-based light-emitting diodes (LEDs) as well as for the evaluation of their degradation. We present a review of quality and reliability investigations of high-power (1 W and 3 W) white light-emitting diodes during long-term aging at the maximum permissible forward current at room temperature. The research was centered on the investigation of blue InGaN and AlInGaN quantum wells (QWs) LEDs covered by a YAG:Ce3+ phosphor layer for white light emission. The current-voltage, light output power, and low-frequency noise characteristics were measured. A broadband silicon photodetector and two-color (blue and red) selective silicon photodetectors were used for the LED output power detection, which makes it possible to separate physical processes related to the initial blue light radiation and the phosphor luminescence. Particular attention was paid to the measurement and interpretation of the simultaneous cross-correlation coefficient between electrical and optical fluctuations. The presented method enables to determine which part of fluctuations originates in the quantum well layer of the LED. The technique using the two-color selective photodetector enables investigation of changes in the noise properties of the main blue light source and the phosphor layer during the long-term aging.

Study on the Influence of LED Spectrum on the Visual and Nonvisual Effects in the Interior Zone of Tunnels

Judicious use of lamps is of profound significance to improve the internal traffic safety of tunnels. This study evaluated the biological effects of spectrum on human visual and nonvisual under mesopic vision category. According to the difference of human eyes’ response to the visual and nonvisual biological effects of different wavelengths of light radiation, a method of applying the mesopic visual spectral luminous efficiency curve to the assessment of nonvisual biological effects and blue light hazards is proposed. The results show that, in theory, under mesopic vision category, the spectrum with high correlation color temperature (CCT) and high color rendering index (CRI) has higher blue light content Z-value and has greater impact on human nonvisual effects and blue light radiation damage, but it can also provide higher human perception luminance. The visual effect detection experiment of driving in the interior zones of the tunnel is simulated in the laboratory, and the critical flicker frequency and reaction time are taken as physiological indexes. The results show that the spectrum with high CCT and high CRI corresponds to lower critical flicker frequency drop value and faster reaction time, which has a positive effect on improving driving safety. Therefore, this paper suggests that the LED with high CCT and high CRI (CCT = 6500 K, CRI2012 = 95) should be used in the interior zones of the tunnel with relatively short lighting section, and the CCT and CRI should be appropriately reduced in other road environments with long lighting section to reduce the impact of spectrum on nonvisual photobiology, so as to improve road traffic safety.

Staphylococcus aureus growth delay after exposure to low fluencies of blue light (470 nm).

Antibiotic resistance is one of the greatest challenges to treat bacterial infections worldwide, leading to increase in medical expenses, prolonged hospital stay and increased mortality. The use of blue light has been suggested as an innovative alternative to overcome this problem. In this study we analyzed the antibacterial effect of blue light using low emission parameters on Staphylococcus aureus cultures. In vitro bacterial cultures were used in two experimental approaches. The first approach included single or fractionated blue light application provided by LED emitters (470 nm), with the following fluencies: 16.29, 27.16 and 54.32 J/cm2. For the second approach a power LED (470 nm) was used to deliver 54.32 J/cm2 fractionated in 3 applications. Our results demonstrated that bacterial cultures exposed to fractionated blue light radiation exhibited significantly smaller sizes colonies than the control group after 24 h incubation, however the affected bacteria were able to adapt and continue to proliferate after prolonged incubation time. We could conclude that the hypothetical clinical use of low fluencies of blue light as an antibacterial treatment is risky, since its action is not definitive and proves to be ineffective at least for the strain used in this study.

Chronic herpetic stomatitis: prevention aimed at reducing the number of active sources of infection

One of the most common conditions in dental practice is herpetic stomatitis, caused by the herpes simplex virus type 1. The aim of the study was to evaluate the therapeutic and preventive effect of complex therapy of chronic herpetic stomatitis caused by the herpes simplex virus type 1. The study included 100 patients with chronic herpetic stomatitis aged 26 to 70 years, 50 of whom received standard treatment, and 50 received additional drugs «Timalin», «Leikinferon», «Stomat» and blue light radiation directly on the area of the formations. The results showed a significant reduction in the duration of the active stage of the disease, an increase in the duration of remission and a reduction in the number of relapses. The proposed therapeutic complex is an important link in the prevention of herpesvirus infection, which significantly reduces both the number of people with active infection and the duration of contact of dental clinic staff with patients who have the virus detected in saliva.