Method Of Biotesting Research Articles

АЛЛЕЛОПАТИЧЕСКАЯ АКТИВНОСТЬ ТРЕХРЕБЕРНИКА НЕПАХУЧЕГО (TRIPLEUROSPERMUM INODORUM (L.) SCH. BIP.)

The purpose of reseach was to study the allelopathic activity of T. inodorum in laboratory conditions against seeds and seedlings of watercress (Lepidium sativum L.). Objectives: to identify the effect of aqueous extracts of different concentrations of the dry aerial part of T. inodorum on the dynamics of germination and the initial growth of test plant seedlings; to compare the allelopathic effects of T. inodorum identified by two biotesting methods. We used classical methods for determining the allelopathic activity of plants by biotesting on seeds and seedlings of higher plants. The preparation of a concentrated (1 : 25) aqueous extract was carried out using the hot extraction method (4 g of the above-ground part of the three-rib was poured into 100 ml of boiling water and infused for 1 hour). By successively diluting the initial extract, solutions of lower concentrations were obtained (1: 50, 1: 100 and 1: 200). The results obtained indicate a high allelopathic activity of aqueous extracts of the dry aerial part of T. inodorum, which is expressed in a decrease in seed germination and inhibition of seedling growth. With an increase in the concentration of aqueous extracts of three-ribs, the sizes of the root and hypocotyl naturally decrease. Moreover, the most sensitive organ of the test plant is the root, the size of which at the weakest concentration (1: 200) decreases by almost 2 times, while the size of the hypocotyl decreases slightly. A more clear concentration dose-effect relationship was shown by the results of biotesting for root elongation. As the concentration of extracts increases, the size of watercress roots gradually decreases, and the toxicity index of aqueous extracts increases from 21.4 to 86.6 %.

Influence of dissolved oxygen in the environment on toxicity indices obtained by various bio-testing methods

RELEVANCE of the study comes from the understanding of the necessity of continuous development of toxicological analysis. Since The simplest organisms are used in toxicological analysis as bioindicators, the reactions of which to the presence of certain pollutants will always differ, the only way to assess the usefulness of a bioindicators as a tool is to study its behavior under specific tasks. Biondicators differ in their metabolic properties, in particular, in the ways of obtaining energy from the presence of molecular oxygen in the environment. However, it is assumed that the presence of different concentrations of oxygen in the environment affects the behavior of the simplest organisms, which, in its turn, can affect the results of toxicological analysis. Previously, this effect has not been studied. THE PURPOSE. The research of the effect of dissolved oxygen on toxicity indices obtained using of bacteria Escherichia coli (Migula) Castellani and Chalmers and ciliates Paramecium caudatum Ehrenberg, METHODS. Obtaining indices of toxicity is given with different concentrations of dissolved oxygen in the environment, which are distilled water and Bonaqua brand water, by the bioluminescent reaction of bacteria and chemotactic reaction of ciliates. RESULTS. With an increase in the concentration of dissolved oxygen in the environment, the bioluminescence of bacteria increases, therefore, the toxicity index decreases. No effect on ciliates is observed. CONCLUSION. It can be concluded that dissolved oxygen does not affect the biotest analysis using ciliates. When using bacteria as a test organism, an error occurs in the toxicity index.

Study of the Ecotoxicity of Oil-Containing Wastewater Treated in the Helio Installation by Biotesting Method

Study of the Ecotoxicity of Oil-Containing Wastewater Treated in the Helio Installation by Biotesting Method

Soils in the current waste management system

This article is part of the dissertation research. In modern conditions of active construction, the volumes of excavated soil can amount to hundreds of thousands and millions of cubic meters, making up the bulk of waste generated in the process of engineering and economic activities. Such significant volumes of waste (in the form of soil) pose the challenge of making appropriate decisions about their subsequent disposal, reuse or disposal. To solve such issues, it is necessary to know the system of waste management, which is soil, and the current shortcomings in the principles of organization and functioning mechanisms of this system. The authors of the presented article analyzed the system for handling soils falling into the category of waste. In general, soils are complex multicomponent systems characterized by dynamic changes in composition, structure and properties. Taking into account the specifics of the object under study, the weakest aspects and controversial issues were identified in the analyzed regulatory and methodological materials. One of which is the very fact that soil is categorized as waste from a regulatory point of view. The article examines the contradictions in the definitions used in regulatory documents, the position of soils in the overall waste management system, as well as the procedure for establishing the hazard class of waste; Particular emphasis is placed on the need to use biotesting methods to confirm the V hazard class of waste. The article presents the generalized results of large-scale experimental studies by the team of authors, obtained when assessing the hazard class of waste soils, carried out for the purity of the experiment on soils under the conditions of modeling different in composition and level of pollution. Based on the results obtained, basic proposals have been formulated for improving approaches in the current system for handling soils that fall into the category of waste during engineering and economic, and, above all, engineering and construction activities.

Каспий теңізінің суы мен топырағының уыттылық деңгейі

Currently, the ecological state of the Caspian Sea, located in the southwestern part of the country, requires constant monitoring and cleaning due to various polluting factors, especially the rapid development of the oil industry. Assessing the level of seawater pollution using biotesting methods that do not harm the environment from an ecological point of view is widely used. The microbiological composition of research objects isolated from the Caspian Sea was determined. In objects isolated from water samples, the total number of microbes ranges from (1.9±0.1)*102 to (6.2±0.2)*102, while in soil samples the figure was determined to be up to (9.7± 0.3)*105. The isolated cultures were analyzed morphologically, as a result, aerobic, normal motile cocci, short- and long-rod bacteria, as well as mycelium were discovered. During the study, a biotesting method was implemented using a biological sample object - a representative of the crustacean Daphnia magna. During the study, it was established that soil samples from Morport-1 and Morport-2 were 100% toxic to the biotest objects from the first day (in a ratio of 60:40). As a result of biotesting, the Morport-1 and Morport-2 samples, considered highly contaminated, revealed a toxicity level of more than 50%.

DETOXIFICATION OF USED SYNTHETIC MOTOR OILS WITH BIOCOMPOSITIONS BASED ON HUMIC ACIDS IN WATER

Among the modern technologies of remediation of oil-contaminated wastewater, the most promising are technologies based on biological methods of purification, namely, on the process of self-purification using various consortia of microorganisms characterized by an increased ability to biodegrade hydrocarbons of oil and petroleum products. This article is devoted to the assessment of the detoxifying ability of new biocompositions based on microorganisms-oil destructors in combination with natural dispersants – humic acids in relation to used synthetic motor oil in water. Biocompositions based on humic acids isolated from the peat of the Tula region: reed lowland and black-alder lowland, and microorganisms-oil destructors of the genus Rhodococcus, producing biological surfactants and capable oxidizing a wide range of petroleum hydrocarbons due to the presence of enzymatic systems, have been studied. The detoxifying ability of biocompositions was determined by the method of biotesting by assessing the toxic effect on the test object duckweed small. The reduction of the toxic effect by the detoxification coefficient was achieved by more than 50%. Attention is focused on the advantages of biotesting in comparison with analytical methods, which consist in ease of use, expressiveness in determining results, cost–effectiveness and, most importantly, the ability to judge how dangerous a specific amount of xenobiotic is for the vital activity of organisms. The experiments carried out prove that the developed biocomposition affects the dispersed state of used synthetic engine oil in water, and also contributes to the degradation of its components. The obtained biocompositions can be used as complex biological products for biotechnological remediation of aquatic environments using in situ technology.

BIOTESTING OF SOIL CONDITIONS AT THE TERRITORIES ADJACENT TO AIRPORTS

The development of civil aviation is accompanied by a constant increase in man-made load on the environment. The application of methods of bioindication and biotesting of anthropogenic and technogenic influences on the ecosystem components is one of the possible options for monitoring the state of the environment at territories subject to technogenic stress due to the activities of environmentally hazardous enterprises. To study the level of man-made impact of airport activities on the state of the soil (namely, phytotoxicity), at the territory adjacent to the airport "Kyiv" named after I. Sikorskyi International Airport from the upper and lower levels at different distances from the airport runway (from 5 m to 2 km) soil samples were taken using the envelope method. As a control (conditionally clean soil), a soil sample collected at the territory of Holosiiv Park (soil type: dark gray forest soils) was used. In total, six soil samples were analyzed. On the third day of germination the growth characteristics of Allium cepa seedlings were determined. Test parameters that were used to determine the phytotoxic effect: the percentage of seed germination, namely the energy of its germination, the length of the root and the length of the stem. The analysis of the obtained data on the germination of Allium cepa seeds showed that the lowest germination was recorded for the soil samples that were taken at a distance of 5 and 1500 m from the runway, which indicates an increased level of phytotoxic impact due to the activities of the airport.
 The greatest phytotoxic effect for the stem of Allium cepa seedlings was observed for the soil sample located at a distance of 5 m from the ZPS. For soil samples taken at a distance of 5 m to 1000 m, i.e. with distance from the runway of the airport, a decrease in the level of phytotoxicity of the soil is observed. Only when approaching the highway (at a distance of 1,000 m to 2,000 m) there was observed an increase in phytotoxicity of the soil again.
 Among the investigated samples of meristem tissues, the presence of mitotic activity of cells was observed in the meristems of root tip samples of onion seedlings germinated on soil samples that were taken at a distance of 5 m, 1500 m and 2000 m from the airport. The determined mitotic indices (MI) for these soil samples are as following: for a soil sample taken at a distance of 5 m, it was 2.9 %; for a soil sample taken at a distance of 1500 m was 2.6 %; for a soil sample taken at a distance of 2000 m was 2.6 %. The research results confirm the need for constant monitoring of the soil condition at these technogenically loaded territories, in order to increase the level of environmental safety of these territories.

Polychlorinated dibenzo-p-dioxins and furans: methods of analysis, distribution in the Moscow region and application of biotesting methods to them

The review presents data on chemical-analytical methods of PCDD, PCDF determination and biotesting methods used for toxicological assessment of pollutants. Distribution of PCDDs, PCDFs on the territory of Moscow is analyzed. Analysis of publications of Russian and foreign authors showed that the currently existing methods of biotesting are in fact untested for dioxins. In order to quickly establish the toxicological effect of persistent organic pollutants in soil, it is suggested to use biotesting methods, with inclusion of test organisms representing the main trophic levels of ecosystems: producers, consumers, and decomposers.

Electrochemical Biosensors for Express Analysis of the Integral Toxicity of Polymer Materials.

Biosensors based on an oxygen electrode, a mediator electrode, and a mediator microbial biofuel cell (MFC) using the bacteria Gluconobacter oxydans B-1280 were formed and tested to determine the integral toxicity. G. oxydans bacteria exhibited high sensitivity to the toxic effects of phenol, 2,4-dinitrophenol, salicylic and trichloroacetic acid, and a number of heavy metal ions. The system "G. oxydans bacteria-ferrocene-graphite-paste electrode" was superior in sensitivity to biosensors formed using an oxygen electrode and MFC, in particular regarding heavy metal ions (EC50 of Cr3+, Mn2+, and Cd2+ was 0.8 mg/dm3, 0.3 mg/dm3 and 1.6 mg/dm3, respectively). It was determined that the period of stable functioning of electrochemical systems during measurements was reduced by half (from 30 to 15 days) due to changes in the enzyme system of microbial cells when exposed to toxicants. Samples of the products made from polymeric materials were analyzed using developed biosensor systems and standard biotesting methods based on inhibiting the growth of duckweed Lemna minor, reducing the motility of bull sperm, and quenching the luminescence of the commercial test system "Ecolum". The developed bioelectrocatalytic systems were comparable in sensitivity to commercial biosensors, which made it possible to correlate the results and identify, by all methods, a highly toxic sample containing diphenylmethane-4,4'-diisocyanate according to GC-MS data.

Video Image Processing of Daphnia magna Straus (Cladocera, Crustacea) as a Basis for Automated Biotesting Methods

Video Image Processing of Daphnia magna Straus (Cladocera, Crustacea) as a Basis for Automated Biotesting Methods

Video image processing of Daphnia magna Straus (Cladocera, Crustacea) as a basis for automated biotesting methods

Computer processing of a video sequence with test organisms is a promising direction in the development of biotesting, as the throughput of methods per unit time increases significantly and several test reactions are taken into account simultaneously. The aim of the work is to develop and test an automated method for considering a complex of D. magna test functions for further assessment of the toxicity of aquatic environments. Videos with D. magna were processed using the Python programming language and the OpenCV computer vision library. The developed algorithm makes it possible to detect D. magna individuals of different ages, to determine their linear dimensions, velocities and accelerations. This functionality, applied to model groups of D. magna, makes it possible to assess the acute toxicity (by lethal and sublethal effects) and chronic toxicity of samples (by the number of juveniles born and their physiological reactions).

Sorption and Biodestruction of Microcystin-LR by <i>Penicillium verrucosum</i> CP4 Strain Isolated from the Bottom Sediments of Sestroretsky Razliv Lake

The strain of fungus СР4 capable of degrading microcystin – LR (MC-LR) was isolated from the bottom sediments of Sestroretsky Razliv Lake. Based on DNA ITS sequencing and morphological analysis, the CP4 strain was identified as Penicillium verrucosum. The decrease in the content of MC-LR during the cultivation of strain СР4 from 0.64 μg/mL to 0.31 μg/mL occurs mainly due to biodegradation and, to a lesser extent, due to the sorption of the toxin by fungal cells. The method of biotesting (Daphnia magna) showed a decrease in the toxicity of the culture liquid in the process of MC-LR biodegradation by the strain СР4. The obtained results allow us to consider Penicillium verrucosum СР4 as a promising strain for mycoremediation of water bodies contaminated with microcystins.

A Soil Biodiagnostics Methodology and Features of Some Bioindication and Biotesting Methods (Review)

A Soil Biodiagnostics Methodology and Features of Some Bioindication and Biotesting Methods (Review)

A SOIL BIODIAGNOSTICS METHODOLOGY AND FEATURES OF SOME BIOINDICATION AND BIOTESTING METHODS (REVIEW)

The methodology for biodiagnostics of the ecological state of soils and other environmental objects involves the use of two approaches: bioindicative observations in situand biotesting of samples, carried out according to standard methods in controlled laboratory conditions ex situ. An integrated assessment of soils on an interdisciplinary basis in accordance with the international standard ISO19204-2017 makes it possible to diagnose of soils “health” based on biotic parameters in the course of natural environmental observations, ecotoxicity indicators, which are supple-mented by the results of quantitative chemical analysis (TRIAD methodology). For soils, indicators of the state of higher plants and microbial communities, especially in agroecosystems, are of paramount importance. The article analyzes the advantages and limitations of well-known methods of phytoindication, laboratory phytotesting, soil respiration, structural and functional indicators of microbiota diversity and bacterial biosensors. The responses of living systems to the same pollutant content largely depend on the carbon content of organic matter. The existing regulatory framework for the ecological assessment of the biological state of soil ecosystems practically does not take into account this, as well as the level of mineralization and pH of the analyzed objects. For an adequate assessment of the ecological quality of soils, it is proposed to improve the methods of measuring toxicity by more targeted recommendations for application (for example, for certain gradations of humus content, mineralization, pH).

Analysis of Ukrainian potato breeding lines using the DNA marker for the H1 potato cyst nematode gene

Goal. Molecular identification of carriers of the H1 gene among potato varieties of the Polish research department of the Institute of Potatoes of the National Academy of Sciences (IC) and comparison of these data with the results of the biotest analysis for resistance to Globodera rostochiensis.
 Methods. The use of molecular markers that indicate the detection of the resistance allele in the genomic of the variety. The PCR method was used. The lines were also analyzed by a biotest method.
 Results. Screening of allele of the molecular marker H1 gene in a selection of 70 cultivar samples showed that 67 (95.7%) samples have the allele associated with resistance, and 3 — the allele for susceptibility. The paper presents the results of the study of the resistance of potato breeding lines of the Ukrainian breeding of 1—2 years of testing, provided by the Polish Research Station. 60 resistant variety samples were established by the biotest method. 10 variety samples were noted, in which the results of analysis by the molecular methods and bioassay did not match.
 Conclusions. Therefore, a comparison of the bioassay method and molecular studies showed a coincidence of results in 60 (85.7%) resistant breeding lines in the study.

Оценка биологической активности экстрактов из листьев Acer negundo и Robinia pseudoacacia на проростках тест-культур

Ash-leaved maple and black locust belong to the most actively spreading woody invasive species in flora of Belarus. In process of control of these plants by mechanical destruction, a potential use of their phytomass as mulch in gardening is considered. For such usage, the negative allelopathic effect of the phytomass on other plants should be assessed. In the paper the effects of the complex of unidentified biologically active substances from Acer negundo and Robinia pseudoacacia are studied. This is achieved by a method of biotesting: seeds of Lepidium sativum, Raphanus sativus, and Daucus carota were incubated in vitro with water extracts from green leaves of Acer negundo and Robinia pseudoacacia, grounded into powder before extraction. The percent of germinated seeds, length of main root, and length of hypocotylus were recorded. The experimental concentrations of phytomass for extracts were 5, 10, 50, and 100 g/l; distilled water was in control. Two variants of phytomass were tested: green leaves, dried on sun, and green leaves, exposed to rain, but dried on sun before such exposing. The results show that A. negundo has higher allelopathic (phytotoxic) activity, than R. pseudoacacia. In particular, extract from maple (100 g/l) completely suppressed seed germination of all three test plants, whereas extract from black locust (100 g/l) had statistically neutral effect (slightly decreased the percent of germinated seeds) on radish and carrot. As a rule, the inhibitory effect on all three studied parameters of germlings become higher along with increase of extract concentration. Exceptions were the growth of main root in carrot, which was slightly stimulated by extracts from maple (10 g/l) and black locust (50 g/l). The leaf mass of both species after exposing to rain partly lost its inhibitory allelopathic activity. The phytomass of A. negundo after such exposition demonstrated 2.3 times less inhibition effect on growth of roots in watercress (extract 10 g/l). In some cases the phytomass, exposed to rain, had stimulating action on germlings: extract from maple (5 g/l) increased the percentage of germinated seeds in carrot on 25 %; extract from black locust (5 g/l) provoked 1.9 times elongation of root in carrot in comparison with control; extracts from black locust (5-50 g/l) stimulated 1.3-1.4 times elongation of hypocotylus in watercress. Test plants showed different sensitivity to the same extracts. In particular, black locust extract (100 g/l) decreased the number of germinated seeds for watercress to 3.8 %, but only to 89.3 % for carrot. Black locust extract (leaves, exposed to rain, 100 g/l) decreased the average root length in watercress in 4.5 times, but in radish - in 1.5 times.

Investigation of Toxicological Properties of Organic Agricultural Waste

The increasing volumes of formation and accumulation of organic agricultural waste pose the task of investigating the nature of the impact of waste on the environment and finding ways to efficiently dispose of them. The toxicological properties of organic animal waste (cattle manure) were investigated by the method of biotesting. Planktonic non-oceanic crustaceans Daphnia magna Straus were used as test objects. The physicochemical characteristics of the waste were also determined: humidity, ash content, bulk density, the value of the hydrogen pH of the water extract. It is shown that the waste has hazard class IV, that is, it is low-hazard. Possible ways of waste disposal in the conditions of an agro-industrial enterprise are considered.

Assessment of Water Quality in Water Intake Points the City of Grozny by Biotesting Methods

A study of 184 water samples in the water intake areas of the city of Grozny (Goity, Sunzhensky and Chernorechensky) was carried out using generally accepted biotesting methods. Luminescent bacteria E. coli and freshwater crustaceans Daphnia magna Straus were used as test objects. The toxicity of samples from the Sunzha water intake in the summer period during biotesting on bacteria and a different degree of chronic toxicity of water samples during biotesting of water on daphnia, depending on the place of water intake, are shown.

Some data on prevalence of microscopic fungi in conditions of the Republic of Tatarstan

Research on plant feedstock for farm animals and poultry is now a pressing issue. Seeding with field isolates occurs in the soil layer in the autumn period. The infestation of isolates remains in the form of spores on crop residues during the winter period. The research aimed to conduct a mycological assessment of the field isolates prevalence in soil, green mass, and agricultural products in the farms of the Agricultural Production Cooperative [APC] “Tukaya” of the Baltasinsky district, the Agricultural firm “Archa” of the Arsky district, and the APC “Kubnya” of the Kaibitsky district of the Republic of Tatarstan. The mycological screening was carried out in the specialized laboratories of the Federal Center for Toxicological, Radiation and Biological Safety. To determine the toxicity, a biotesting method based on the survival rate of ciliated cultures was used after one hour of exposure in the extract of the studied product. The climatic conditions of the spring-summer period of 2020 were characterized by increased humidity in combination with temperature changes. In the research, a spread of fungi of the genus Fusarium (F. oxysporum, F. graminearum F. sporitrichioides), Penicillium (P.notatum, P.glaucum, P.chusodepim, P. expansium) was detected in crops. And fungi of the genus Aspergillus were more often sown in grain feeds (A.fumigatus, A. flavus, A. niger). During the determination of toxicity, it was found that all the objects studied: soil, green mass, and feed are non-toxic, the survival rate of infusoria was 86%–100%. The authors recommend conducting regular feed screening and taking preventive measures that will make it possible to prevent the spread of aggressive field isolates in the agricultural complexes of the Republic of Tatarstan.

Investigation of the influence of hyperthermia and soil pollution with the petrochemicals on test objects using the method of mathematical planning

Purpose. To increase the efficiency of using methods for assessing the level of soil contamination by oil products against the background of the influence of other factors. Methodology. The authors consider the possibility of using bioassays to study the impact of several stressors on the test system. Based on the theory of experiment planning, a methodology for researching the influence of hyperthermia and soil contamination with kerosene on the growth parameters of test objects was developed. On the basis of the obtained experimental data, regression models were built which allow finding a numerical estimate of the impact of stress factors on changes in the characteristics of the test object. Findings. It was determined that, as a rule, in order to assess the influence of stressful factors when normalizing the assumed levels of their influence on humans and ecosystems using biotesting methods, such an assessment is carried out for individual factors. But, in the real conditions of existence of plants and organisms, they are exposed to the simultaneous influence of many factors that can interact non-additively, i.e. as antagonists or synergists. In order to increase the efficiency of the use of methods for biotesting of the level of soil contamination by oil products against the background of the influence of other factors, the authors applied one of the methods of mathematical planning of the experiment. It was concluded that the effect of one factor depends, to a certain extent, on the effect of the other factor, the effect of which was studied in the work. The fact of the non-additive effect of the factors used in the experiment makes it possible to recommend the use of test objects in the practice of monitoring the condition of soils in technogenically loaded territories previously exposed to the action of hyperthermia. Originality. The toxic effect of the petroleum product depends, to a certain extent, on the effect of hyperthermia. Pretreatment of the test objects with a hyperthermic factor in a hormesis dose had a preventive effect, increasing the resistance of the test objects to the effect of the petroleum product. Practical value. The fact of the non-additive effect of the factors used in the experiment makes it possible to recommend the use of test objects previously exposed to the action of hyperthermia for monitoring the condition of soils in technogenically loaded territories.