Concentration Of Microorganisms Research Articles

Photocatalytic hydrogen peroxide production in natural seawater by AgQDs(0D)/Bi2O3(3D) hybrid structure for in-situ bacterial inactivation

Minimizing the concentration of marine microorganisms in ballast water efficiently addressed the potential threat of ecosystem pollution and marine creature invasion. Here we establish a ballast water treatment system without other additional sacrificial agents to in-situ produce H2O2 decomposition further into robust oxygen species •OH for inactivation of marine microorganisms. Typically, the introduction of AgQDs improved the absorbance of visible light and the 7%AgQDs/Bi2O3 catalyst achieved a high photocatalytic sterilization of 87.6 % for bacterial inactivation with a yield of H2O2 that reached 35.62 μM in natural seawater. Besides, the generation of H2O2 is mainly demonstrated via the oxygen reduction reaction pathway, and AgQDs catalyze the generation of •OH from active site occupied an important role rather than H2O2 or •O2–. Meanwhile, we revealed that AgQDs acted as oxygen adsorption centers, activation centers, and photocatalytic reaction centers to facilitate the transportation of charge carriers for enhanced photocatalytic activities, and hot electrons were generated on AgQDs sites with the assistance of visible light illumination to convert molecular oxygen to H2O2 in one step, which offers some experimental reference value for rational treatment of ballast water systems.

Analysis of bio-convective heat transfer over an unsteady curved stretching sheet using the shifted Legendre collocation method

Bio-convection is used in many ecologically beneficial applications, including pharmaceuticals, biological polymer production, and other eco-friendly uses. Several of these applications, such as the production of plastic films and polymer sheets, rely on stretching surface technology because the heat transfer rate determines the ultimate product quality at the stretching surface. Therefore, this study examines the bio-convective heat transfer caused by the swimming of gyrotactic micro-organisms in a nanofluid flowing over an unsteady curved stretched sheet. Local similarity transformations are utilized to alter the nonlinear partial differential equations. The resulting nonlinear system of ordinary differential equations is solved using the shifted Legendre collocation method. The effects of many influential parameters on motile micro-organism concentration and temperature, velocity, and nanoparticle concentration profiles are plotted and discussed. The velocity field is reduced when the slip parameter increases. According to this focused study's results, the concentration of motile bacteria drops dramatically when the curvature parameter increases. The Brownian motion parameter, thermophoresis parameter, and Peclet number reduce the motile micro-organism number. Motile micro-organism dispersal improves with an increase in bio-convective Schmidt number.

Cattaneo-Christov Double Diffusion (CCDD) on Sutterby Nanofluid with Irreversibility Analysis and Motile Microbes Due to a RIGA Plate.

In this article, a Riga plate is exhibited with an electric magnetization actuator consisting of permanent magnets and electrodes assembled alternatively. This Riga plate creates an electric and magnetic field, where a transverse Lorentz force is generated that contributes to the flow along the plate. A new study field has been created by Sutterby nanofluid flows down the Riga plate, which is crucial to the creation of several industrial advancements, including thermal nuclear reactors, flow metres, and nuclear reactor design. This article addresses the second law analysis of MHD Sutter by nanofluid over a stretching sheet with the Riga plate. The Cattaneo–Christov Double Diffusion heat and mass flux have been created to examine the behaviour of relaxation time. The bioconvection of motile microorganisms and chemical reactions are taken into consideration. Similarity transformations are used to make the governing equations non-dimensional ordinary differential equations (ODE’s) that are subsequently solved through an efficient and powerful analytic technique, the homotopy analysis method (HAM). The effect of pertained variables on velocity, temperature, concentration, and motile microorganism distributions are elaborated through the plot in detail. Further, the velocity distribution enhances and reduces for greater value Deborah number and Reynold number for the two cases of pseudoplastic and dilatant flow. Microorganism distribution decreases with the augmented magnitude of Peclet number , Bioconvection Lewis number , and microorganism concentration difference number . The entropy production distribution is increased for the greater estimations of the Reynolds number and Brinkman parameter . Two sets of graphical outputs are presented for the Sutterby fluid parameter. Finally, for the justification of these outcomes, tables of comparison are made with various variables.

Entropy generation minimization in the Blasius–Rayleigh–Stokes nanofluid flow through a transitive magnetic field with bioconvective microorganisms

The goal of this study is to underscore the attributes of nanofluid by discussing the Blasius-Rayleigh-Stokes (BRS) nanofluid flow with effects of modified Fourier law with gyrotactic microorganisms influenced by the transitive magnetic field past a moving semi-infinite plate. The proposed flow is supported by the non-uniform heat sink/source and radiation with zero mass flux at the surface. Analysis of entropy generation is also a part of this study. The most notable aspect of the presented model is that it discusses the entire problem using the Blasius-Rayleigh-Stokes flow. The envisioned model is reflected in the form of a system of PDEs that is transformed into a highly nonlinear system of ODEs engaging the boundary layer approximations and handled numerically. Graphical illustrations are designed for the arising parameters versus the associated profiles. It is comprehended that the thermal profile lowers for the thermal relaxation parameter. The results also disclosed that the motile density profile declines for Peclet number, and microorganism concentration difference parameter. Furthermore, the mass transfer rate is reduced by rising the chemical reaction parameter. Entropy generation upsurges versus heat generation absorption coefficients. A check for the validation of the presented model is also added to the problem.

Entropy Analysis of Sutterby Nanofluid Flow over a Riga Sheet with Gyrotactic Microorganisms and Cattaneo–Christov Double Diffusion

In this article, a Riga plate is exhibited with an electric magnetization actuator consisting of permanent magnets and electrodes assembled alternatively. This exhibition produces electromagnetic hydrodynamic phenomena over a fluid flow. A new study model is formed with the Sutterby nanofluid flow through the Riga plate, which is crucial to the structure of several industrial and entering advancements, including thermal nuclear reactors, flow metres and nuclear reactor design. This article addresses the entropy analysis of Sutterby nanofluid flow over the Riga plate. The Cattaneo–Christov heat and mass flux were used to examine the behaviour of heat and mass relaxation time. The bioconvective motile microorganisms and nanoparticles are taken into consideration. The system of equations for the current flow problems is converted from a highly non-linear partial system to an ordinary system through an appropriate transformation. The effect of the obtained variables on velocity, temperature, concentration and motile microorganism distributions are elaborated through the plots in detail. Further, the velocity distribution is enhanced for a greater Deborah number value and it is reduced for a higher Reynolds number for the two cases of pseudoplastic and dilatant flows. Microorganism distribution decreases with the increased magnitude of Peclet number, Bioconvection Lewis number and microorganism concentration difference number. Two types of graphical outputs are presented for the Sutterby fluid parameter (β = −2.5, β = 2.5). Finally, the validation of the present model is achieved with the previously available literature.

Primary Sewage Sludge Treatment Using A Spiral Support System

Sewage sludge (wastewater treatment solids) is an organic and nutrient resource that is generated during wastewater treatment and is utilized as biosolids in landfills, fertilizer, or compost it requires treatment to reduce the microbial load and the concentration of organic matter and pollutants such as metals. Aerobic digestion has been used for the stabilization of sewage sludge, and the use of biodiscs has been limited to primary sewage rather than sewage sludge. Therefore, this paper shows that the primary sewage sludge from a previously sonicated municipal sewage treatment plant can be stabilized using a spiral support biodisc, which is shown to be an effective mechanism with which to reduce the concentration of pathogenic microorganisms in residual sludge and also reduce the concentration of organic carbon, ammonia-nitrogen (NH3-N), and soluble phosphorus. The experimental results using the spiral support biodisc are better compared to those using the conventional biodisc.

Changes in the Microbial Distribution of Buyeo Royal Tombs: Tomb No. 1

Built in the 6th and 7th centuries during the Baekje period, the Buyeo Royal Tombs consist of seven tombs, including Tomb No. 1, which contains murals. To preserve Tomb No. 1 from damage caused by microorganisms, periodic microbial-distribution investigations are conducted. Following such investigations in August 2016, June 2018, and November 2019, the microbes were classified according to the investigation period, location of collection, and space. This study compares and analyzes the results. The concentration of airborne microorganisms in Tomb No. 1 and the number of microbial genera identified in each space of the tomb decreased as proximity to the main room with murals diminished. During the investigation period, the genera <i>Bacillus, Cladosporium, Penicillium,</i> and <i>Streptomyces</i> were commonly identified on Tomb No. 1. The microorganisms collected f rom the main room walls were mostly isolated from the east and west walls where the genera <i>Bacillus, Cupriavidus, Paenibacillus, Pseudomonas,</i> and <i>Streptomyces</i> were commonly identified in three or more walls. In particular, the genus <i>Streptomyces</i> is a dangerous strain capable of damaging murals by penetrating into and discoloring the pigments on them. The data generated from this study may be useful for future research on microbial distribution in other domestic mural tombs and those located in North Korea and abroad.

The effect of silicon and calcium additives on the growth of selected groups of microorganisms in substrate used in soilless cultivation of strawberries

The aim of the study was to evaluate the impact of silicon (Si) and calcium (Ca) added to the substrate (perliteor its mixture with peat) used in soilless strawberry cultivation on the number of different groups of microorganisms in the substrate. Research was conducted on a farm located in southern Poland in which soilless cultivation of strawberries in gutters, under covers, with an irrigation system was carried out. The microbiological analyzes were performed by serial dilution method. The analyzes included determination of the total number of bacteria, actinobacteria, fungi and aerobic atmospheric nitrogen assimilators of the Azotobacter genus. In this work, we showed that the concentration of microorganisms associated with the cultivation substrate may be influenced by the presence of silicon and calcium added to the composition of the substrate. Correlation analysis showed that the addition of Si + Ca to the substrate affects increase in the total number of bacteria in the substrate. The obtained results confirm that the cultivation substrate can be modified in such a way that it is more conducive to the multiplication and survival of bacteria associated with the substrate.

Triple stratification impacts on an inclined hydromagnetic bioconvective flow of micropolar nanofluid with exponential space-based heat generation

The present work aims to analyze the effects of magnetohydrodynamics, heat and mass transfer, and gyrotactic microorganism behavior on the bioconvective micropolar nanofluid flow subject to triple stratifications and Cattaneo–Christov double diffusion over a stretched surface. The dimensional system of differential equations has been simplified to dimensionless with suitable non-dimensional quantities and suitable similarity transformations. An efficient numerical technique bvp4c through MATLAB has been implemented to devise the solution of the non-dimensionalized system of governing equations. The significant outcomes of the current analysis are that the amplification of magnetic parameter intensifies the flow velocity and shows the reverse effect for the fluid temperature. The enhancement of micropolar parameter upgrades microrotation, while it exhibits opposite effect for the fluid temperature and nanoparticle concentration. Microorganism concentration peters out with a rise in Peclet number. Gyrotactic microorganism thermal stratification augmentation leads to the diminution of velocity and thermal boundary layer thickness. When gyrotactic microorganism concentration difference parameter rises from 0.1 to 0.8, skin friction whittles down by 12.5%, and wall motile microorganism number ameliorates by 50%.

Indoor Air Quality in Naturally Ventilated and Mixed Model Ventilation in Public University of Pakistan

Airborne microorganisms have potential to cause infections and respiratory diseases like asthma. It is necessary to reduce the human exposure to such pathogens. This study was based on the determination of indoor environmental quality and the quantification of microbial load in a university premises in Karachi, Pakistan. Seven different locations with high human occupancy during office hours were sample din winter and summer. Culturable microorganisms i.e. bacteria and fungi were collected on selective media by Spin Air V2 sampler. The average bacteria and fungi concentration sin winter were133 ± 26colony forming unit per cubic meter (CFU.m-3) and 199 ± 59 CFU.m-3 respectively. In summer counts were higher than winter with bacterial and fungal count of 205 ± 39 and 306 ± 102 CFU.m-3. There was strong correlation (r = 0.8, p = 0.032) between fungal count and humidity, and between bacterial and fungal count (r = 0.802, p = 0.030). The most common culturable airborne fungi in both seasons were Aspergillus, Penicillium, Cladosporium, Fusarium, Alternaria, Stachybotrys, Candida, and Rhodoturola. Resultsindicate that the indoor environment in university premises harbours high concentrations of microorganism and needs regular indoor air quality monitoring and establish local guidelines to prevent diseases.

Multiple slip effects on time dependent axisymmetric flow of magnetized Carreau nanofluid and motile microorganisms

This presented work investigate the bio-convections effects of the magnetized time dependent axisymmetric flow of Carreau-nanomaterial performances with multiple slip effects over a stretching sheet. The momentum, heat, concentration and density of motile micro-organism are renovated into the system of equation via using well known similarity revolution. Well known Mathematical computational techniques and software (i.e. bvp4c and MATLAB) are used to draw graphical and tabular results. Velocity profile equation f^{prime}(zeta ), energy equation theta (zeta ), volumetric nanoparticles phi ,(zeta ), density motile microorganism chi (zeta ).The Carreau viscosity model is use to reduce the viscosity of fluid when W_{e} = 0,,, and ,n = 0. Besides we moderate this into power law index with ,n = 0.5 and ,n = 1.5 partial slip condition of velocity is also instigated at the surface. Gravity dependent gyrotactic nanoparticles are utilized for well observing axisymmetric flow with convective boundary layer condition and comparatively better heat transfer rate result and applicable to maximum realistic approach.

Rotating Flow and Heat Transfer of Single-Wall Carbon Nanotube and Multi-Wall Carbon Nanotube Hybrid Nanofluid with Base Fluid Water over a Stretching Sheet

In this article, numerical simulations of the rotational flow of water-based magnetohydrodynamic (MHD) nanofluid containing single-wall carbon nanotube (SWCNT) and hybrid nanofluid containing single- and multiple-wall carbon nanotube (SWCNT-MWCNT) over a stretching sheet are performed. The primary goal is to improve thermal transport efficiency due to CNTs extraordinary thermal conductivity. The 3D governing equations for microorganism concentration, energy, momentum, concentration, and mass conservation are transformed into 1D ordinary differentiation via similarity transformations. In a MATLAB environment, the resultant system of equations (ODEs) are then solved using Runge–Kutta fourth order with the shooting process. Tables and graphs were used to show the results of physical parameters. According to our findings, enhancing the rotational parameter λ and the magnetic field M reduce the base fluid velocity along the x-axis, and on the other hand, the opposite tendency is shown along the y-axis. Furthermore, the velocities, temperature, and microorganism concentration profiles of hybrid nanofluid (SWCNT−MWCNT/H2O) are found to be higher than those of mono nanofluid (H2O+SWCNT), while the concentration profile is found to be lower.

Use of the Probiotic Bifidobacterium animalis subsp. lactis HN019 in Oral Diseases.

The oral cavity is one of the environments on the human body with the highest concentrations of microorganisms that coexist harmoniously and maintain homeostasis related to oral health. Several local factors can shift the microbiome to a pathogenic state of dysbiosis. Existing treatments for infections caused by changes in the oral cavity aim to control biofilm dysbiosis and restore microbial balance. Studies have used probiotics as treatments for oral diseases, due to their ability to reduce the pathogenicity of the microbiota and immunoinflammatory changes. This review investigates the role of the probiotic Bifidobacterium animalis subsp. lactis (B. lactis) HN019 in oral health, and its mechanism of action in pre-clinical and clinical studies. This probiotic strain is a lactic acid bacterium that is safe for human consumption. It mediates bacterial co-aggregation with pathogens and modulates the immune response. Studies using B. lactis HN019 in periodontitis and peri-implant mucositis have shown it to be a potential adjuvant treatment with beneficial microbiological and immunological effects. Studies evaluating its oral effects and mechanism of action show that this probiotic strain has the potential to be used in several dental applications because of its benefit to the host.

Diagnostically significant culturable obligate microorganisms in the development of periimplantitis

BACKGROUND: The urgency of the problem is conditioned by insufficient study of peri-implantitis microbiota, its changes in the dynamics of the process and in the concurrent course with periodontitis.
 AIM: To justify the diagnostically significant cultivated obligate microorganisms involved in the development of inflammatory processes in the area of the placed implants.
 MATERIALS AND METHODS: The study was conducted in the period 20182022. The study involved 127 patients of a private dental clinic in Kirov, Russia. Kirov LLC Dental Clinic aged 35 to 69 years (53.81.9 years). Men made up 48% and women 52%. Biological material from the peri-implant area was examined. Inoculation on dense culture media of biological material with subsequent calculation of microorganism concentration was carried out according to the Gold method of quantitative four-section inoculation. The species identification of the isolated cultures was carried out by MALDI-TOF mass spectrometry using a Vitek-MS bacteriological analyzer (BioMerieux, France).
 RESULTS: Microorganisms obligate anaerobes playing an important role in the development of peri-implantitis were identified in the investigation. Microorganisms that reduce the development of inflammatory changes in periimplantitis, having an inverse correlation between the concentration of microorganisms and the degree of clinical, hygienic and radiological changes in persons with implants, were named periodontal protectors. Microorganisms contributing to the development of pathological processes in the periimplant zone, having a direct correlation relationship between the concentration of microorganisms and the degree of severity of clinical, hygienic and radiological changes periodontopathogens. This was more pronounced in patients with associated periodontitis. The regularity in the increase of frequency and concentration of several pathogens during the progression of peri-implantitis with predominance of micro-organisms in the periimplant area in those with periodontitis was found.
 CONCLUSION: The microbiota of the peri-implant zones has been analyzed by means of the modern bacteriological method mass-spectrometry. On the basis of the study we substantiate the diagnostically significant microorganisms, respectively increasing (periodontopathogens) and reducing (periodontoprotectors) the development of inflammatory changes at periimplantitis.

Comparative study of two non-Newtonian fluids with bioconvective induced MHD flow in presence of multiple slips, heat source/sink and nonlinear thermal radiation

The present manuscript deals with bioconvective induced magnetohydrodynamic (MHD) flow of non-Newtonian fluids with simultaneous effects of multiple slips, heat source/sink, and nonlinear thermal radiation. Flows of Maxwell and Casson fluids are considered separately, but a single governing momentum conservation equation is constructed by combining these two flow models. Transformed governing equations are solved by MATLAB solver ‘bvp4c’. The objective of the current study is to check the comparative behaviour of two non-Newtonian fluids viz., Maxwell and Casson in presence of induced MHD effect with the bioconvective phenomenon and slip effect. The main findings reveal the growth of velocity and fall of microorganisms’ motile density with induced magnetic number. With higher values of Peclet number and microorganism concentration difference parameter, the microbe's motile density significantly reduces. The temperature hike is witnessed with heat generation/absorption, thermal radiation, and temperature ratio parameters. Also, for a fixed set of values of parameters the Casson fluid velocity is more prominent than the Maxwell fluid velocity and the scenario is the opposite for the motile density of microorganisms. Velocity increases, whereas motile density decreases with raising the amount of magnetic Prandtl number. Casson fluids have more velocity than Maxwell fluids, whereas the movement of the motile density of microorganisms is showing prominency for Maxwell fluids. The magnitude of surface drag and surface cooling rate are at a higher level for Casson fluid in comparison with Maxwell fluid. The motile density number enhances with the microorganism concentration difference parameter and Peclet number.

Development of a bioactive film from fruit seed waste for shelf life extension of tomato (Solanum lycopersicum )

Solanum lycopersicum, a climacteric, and highly perishable commodity suffer significant postharvest loss along the supply chain. Staphylococcus aureus, Bacillus subtilis, Rhizopus stolonifer, and Aspergillus flavus are chief microorganisms responsible for the biological deterioration of tomatoes. The bioactive compounds present in the extracts of Azadirachta indica, Annona squamosa, and Carica papaya seeds effectively inhibit the growth of these spoilage-causing microorganisms. The research work has investigated the minimum inhibitory concentration of the target microorganisms and has incorporated the optimized concentration of the extracts into the biofilm. The designed biofilm was examined for various physical parameters and antimicrobial activity. The shelf-life of tomatoes packed with the bioactive film was extended to 13 days and the physical, physicochemical, and sensory parameters were found to be acceptable. Whereas the control sample was spoiled on day 5. Therefore, the packaging of tomatoes in the antimicrobial bioactive packaging material is a promising approach toward enhancing the shelf life.

Correlation between the Concentration of Secondary Metabolites and Soil Microorganisms in Sophora Koreensis Nakai from Different Habitat

Sophora koreensis is an endemic species of Gangwon-do, Korea, that has a variety of applications for foods and for folk remedies. Here this research analyzed and compared compounds present in leaves, stems, and roots of S. koreensis collected from three different habitats in Chuncheon, Inje and Yanggu in South Korea. This research also analyzed soil microorganisms present in the three habitats to determine the correlation between the compound and microorganisms. N-methylcytisine was the most common compound in all three habitats, but the amounts varied with Chuncheon having the highest amount (509 mg/L), followed by Yanggu and Inje(102 mg/L and 39 mg/L, respectively). The composition of microorganisms also varied by habitat. Yanggu, Inje, and Chuncheon had 1013, 973, and 814 taxa, respectively. According to the phylogenetic relations, the composition of the soil microorganisms in Chuncheon was significantly different from the other two. It contained more PAC000121_g (Solibacteres), major taxa in all three habitats (14% in Chuncheon). In contrast less Opitutus minor taxa was found than Yannggu and Inje. The correlation between the soil microorganism N-methylcytisine was analyzed. Among these microorganisms, Paraburkholderia had a positive correlation with N-methylcytisine. Meanwhile, Rhizomicrobium, CP011215_f (Paceibacter), KB906767_g (Solibacteres) and Opitutus negatively correlated with N-methylcytisine. The results suggested that soil microorganisms in the habitats influenced the variations of the N-methylcytisine.

Enrichment of functional microorganisms in AAO segmental influent-biofilm filler coupling process to improve the pollutants removal efficiency at low temperature

In this study, a coupling anaerobic anoxic oxic (AAO) activated sludge-biofilm process with segmental influent was constructed to increase the concentration of functional microorganisms in the reactor and improve the efficiency of municipal wastewater treatment at low temperature, and investigated the pollutant removal pattern and microbial characteristics at low temperature. Conventional pollutants and sludge characteristics indicator were tested at the segmental influent flow distribution ratio of A1:O1 = 2:1. The study showed that the removal rates of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) were 89 %, 90.74 %, 76.60 %, and 96.60 %, in contrast to the conventional AAO process, at low temperature, COD degradation was concentrated in A1 and O1, simultaneous nitrification and denitrification (SND) occurred in O1 to achieve effective N removal, the phosphorus (P) significant removal in O1. The extracellular polymeric substances (EPS) content of activated sludge in the compartment was negatively correlated with the incoming COD content. And the distribution of carbon and nitrogen sources in the segmental influent contributed to the higher active activity of microorganisms and higher removal efficiency. The analysis of microbial communities in activated sludge and filler samples by Illumina high-throughput sequencing showed that the abundance and diversity of microbial communities in the biofilm were more significant than the activated sludge, and Proteobacteria were the most abundant phylum in the community. The presence of many denitrifying phylum such as Firmicutes and Nitrospira ensured the stability of the modified AAO system at low temperature. Dokdonella, Denitratisoma, Rhodoferax, and other genera ensured efficient phosphorus removal.

The problem of hygienic standardization of air concentration of microorganisms in office premises

The problem of hygienic standardization of air concentration of microorganisms in office premises: ISSN 2223-6775 Ukrainian journal of occupational health Vol.18, No 2, 2022https://doi.org/10.33573/ujoh2022.02.147 The problem of hygienic standardization of air concentration of microorganisms in office premises Leonov Yu.I.1, Nazarenko V.I.1, Myshchenko

The Use of Energy­Saving Ultraviolet Electrical Equipment in Agriculture

It was noted that the optical radiation in the ultraviolet (UV) range plays an important role in agricultural production, and a lack of it leads to the deterioration of animal productivity.Research purpose The study aims to substantiate the parameters of energy-saving agricultural electrical equipment operating in the ultraviolet range.Materials and methods The study shows that it is possible to create a universal therapeutic irradiator based on LEDs with a wavelength of 310 nanometers. The calculation methods are given. The parameters of UV devices for premises disinfection are substantiated. It has been found out that UV radiation increases the polymerization rate of paint coatings and facilitates the creation of energy-saving optical insect traps.Results and discussion The paper provides some examples of own-developed energy-saving systems and their use for the therapeutic irradiation of animals. The replacement of LE-30 fluorescent lamps with LEDs has resulted in a 13-fold reduction in electricity consumption. It has been found out that the use of bactericidal irradiators in poultry houses reduces not only the concentration of microorganisms but also the content of carbon dioxide and ammonia. The use of own-developed irradiators for photochemical polymerization of paint coatings reduces the curing time by 2 times. Optical insect traps have been created based on LEDs with a wavelength of 385 nanometers and the best pulsation frequency of the light source has been determined at 100 hertz.Conclusions The equipment has been developed and the parameters for irradiators operating in the range of 254-390 nanometers were substantiated for a variety of their applications in agriculture.