Paramecium Caudatum Research Articles

Study of the antioxidant activity of rowan extracts (Sorbus aucuparia) by biotesting method

Special importance in modern unfavorable environmental conditions is given to nutrition, which should ensure the weakening of the negative effect of harmful eco-factors on the human body, contribute to increasing its protective and adaptive capabilities, and, as a result, reduce the risk of developing various pathologies. At the same time, it should be taken into account that the diet of a modern person should be rich in biologically active components that can exhibit antioxidant properties. Recently, scientists are increasingly considering plant extracts as sources of antioxidants. Among them, a special role is assigned to Sorbus aucuparia, whose antioxidant activity is described as comparable, or even higher than other fruits. The article presents data on the study of the antioxidant activity of water extracts of mountain ash by biotesting. The antioxidant activity was evaluated using a biological model – Paramecium caudatum, determining the stress resistance of infusoria to hydrogen peroxide. The study revealed an increase in the stress resistance of Paramecium caudatum infusoria when adding extracts of mountain ash to the nutrient mixture compared to the control.

Оценка токсичности очищенных хозяйственно-бытовых сточных вод с целью их использования для орошения

The purpose of the research is to determine the toxicity of domestic wastewater after mechanical and biological treatment and the potential possibility of their use for irrigation. The toxicity of treated wastewater from wastewater treatment plants (Kadamovskiye WWTP) in Novocherkassk by the method of biotesting on different test objects – infusoria (Paramecium caudatum), green protococcal algae chlorella (Chlorella vulgaris Beijer), white mustard seeds (Sinapis alba) is evaluated. Laboratory studies were carried out in the accredited ecological and analytical laboratory of the Federal State Budgetary Institution «RosNIIPM». The results of biotesting at the chlorella test object showed that the treated household wastewater does not have a toxic impact. Biotesting at the infusoria test object determined only the toxic impact of wastewater after biological treatment. The length of the white mustard seed roots in wastewater after mechanical and biological treatment is above 120%, compared with the control, which proves the stimulant effect of these waters. So, according to the results of biotesting domestic wastewater after mechanical treatment from the Kadamovskiye WWTP in Novocherkassk can be potentially used for irrigation. According to the research results, wastewater after biological treatment «has a toxic impact», which causes their use for irrigation only after additional treatment.

Microtubule Disruption Without Learning Impairment in the Unicellular Organism, Paramecium: Implications for Information Processing in Microtubules.

Information processing in microtubules is an open question that has not been adequately addressed. It was suggested that microtubules could store and process information in the nervous system or even support consciousness. The unicellular organism, Paramecium caudatum, has a microtubular structure but lacks a neuron or neural network. However, it shows intelligent behaviors such as associative learning. This property may suggest that the microtubules are involved in intelligent behavior, information storage, or information processing in this organism. To test this hypothesis and study the role of microtubules in P. caudatum learning, we utilized a learning task in which the organism associates brightness in its swimming medium with attractive cathodal shocks. To see if microtubules are an integral part of information storage and processing in P. caudatum, we disrupted the microtubular dynamics in the organism using an antimicrotubular agent (parbendazole). We observed that while a partial allosteric modulator of GABA (midazolam) could disrupt the learning process in P. caudatum, the antimicrotubular agent could not interfere with the learning. Microtubules are probably not vital for the learning behavior in P. caudatum. Consequently, our results call for further investigation of the microtubular information processing hypothesis. Importance of Information processing in microtubules;Microtubules could store and process information in the nervous system;Unicellular organism, Paramecium caudatum, has a microtubular structure but lacks a neuron or neural network. Information processing in microtubules is an open question that has not been adequately addressed. It was suggested that microtubules could store and process information in the nervous system or even support consciousness. The unicellular organism, Paramecium caudatum, has a microtubular structure but lacks a neuron or neural network. However, it shows intelligent behaviors such as associative learning. This property may suggest that the microtubules are involved in intelligent behavior, information storage, or information processing in this organism. To test this hypothesis and study the role of microtubules in P. caudatum learning, we utilized a learning task in which the organism associates brightness in its swimming medium with attractive cathodal shocks. To see if microtubules are an integral part of information storage and processing in P. caudatum, we disrupted the microtubular dynamics in the organism using an antimicrotubular agent (parbendazole). We observed that while a partial allosteric modulator of GABA (midazolam) could disrupt the learning process in P. caudatum, the antimicrotubular agent could not interfere with the learning. Microtubules are probably not vital for the learning behavior in P. caudatum. Consequently, our results call for further investigation of the microtubular information processing hypothesis.

A PRELIMINARY EVALUATION OF WATER QUALITY RELATED TO AQUATIC ORGANISMS IN COMANA POND

In the protected area Natural Park Comana located in Giurgiu County, a survey was carried out between April and June 2021, in order to analyze the water quality related to the aquatic diversity. In the samples collected from Comana Pond, several representatives belonging to four kingdoms were identified: Bacteria (blue-green algae, bacteria), Protista (single-celled and colonial green algae, diatoms, euglenoid flagellates, ciliates), Plantae (filamentous green algae, aquatic freshwater plants) and Animalia (European perch, rudd, pike, Prussian carp). Plankton organisms Achromatium sp., Merismopedia sp., Spirilla sp., Spirulina sp. (bacteria); Gomphonema sp., Melosira sp., Paramecium caudatum (chromists); Desmococcus sp, Ulothrix sp., Volvox sp. (chlorophyte green algae) and also the parasitic nematode Philometroides sanguineus were mentioned for the first time in the Comana Pond. A biometric analysis was performed on a total number of 91 Carassius gibelio individuals and negative pattern of growth and also a fish well-being were postulated. The parasite P. sanguineus was detected in the caudal fin of two Prussian carp individuals. Water samples were collected from 7 sampling points (SP) and were subjected to physico-chemical analysis. It were determined the following parameters: pH, electrical conductivity (EC), total hardness (TH), chemical oxygen demand (COD), phosphate phosphorus (P-PO<sub<4</sub<<sup<3-</sup<), nitrate nitrogen (N-NO<sub<3</sub<<sup<-</sup<), nitrite nitrogen (N-NO<sub<2</sub<<sup<-</sup<). Generally, it was concluded that Comana Pond is a dynamic ecosystem that meets favorable conditions for the growth and development of aquatic organisms.

Біотестування полімерних відходів вилучених з ТПВ

Introduction. Annually, the volume of accumulated polymers in landfills in Ukraine is growing by more than 1 million tons, but the volume of recycled polymer packaging over the past ten years has not exceeded 3%. The goal is to establish the degree of toxicological impact on biosphere objects of polymers extracted from solid waste, to assess the safety of using household polymer waste as a secondary raw material for further processing. The task is to establish the degree of biological and toxicological safety of polymer wastes extracted from solid waste. Methods and techniques: toxicological - determination of water toxicity on acute Daphnia magna according to DSTU 4173: 2003 (ISO 6341: 1996, MOD) and chronic according to DSTU 4166: 2003 (ISO 10706: 2000, MOD), and Paramecium caudatum ciliates, soil microflora reactions (saprotrophic soil bacteria CFU / g) according to MR 2609-82, the assessment of phytotoxic effects on higher plants was carried out by vegetation methods according to ISO 17402-2008, ISO 17126-2005a, ISO 22030: 2005b, ISO 11269 -1:2012a. Results. The research results show that aqueous extracts from waste polymers extracted from solid waste and their mixture do not have a pronounced toxic effect on aquatic organisms. There is no significant effect on soil bacteria. The study of the effect of polymer waste on seed germination did not reveal phytotoxic effects for any crop. A slight phytotoxic effect was observed during the study of PVC and PS waste. Wheat and mustard were the most sensitive. The level of phytotoxic effect was within acceptable limits and did not exceed 5.67%. Evaluation of phytotoxic effects on stem length showed the presence of effects from all processed products except PVC. The impact, characterized as weak, ranged from - 2.06% (PP) to - 13.27% (PS). The effect on root length was found for samples with PS waste (-7.23%), which was characterized as weak and PVC (-43.52%) - medium. Watercress and mustard were the most sensitive plants to the effects of polymer waste. Conclusions. The studied samples of polymer waste do not show hygienically significant toxic effects on water and soil test objects, even in concentrations of 1: 1, so the impact on the above test organisms polymer waste removed from solid waste is classified as hazard class 4. According to the assessment of phytotoxic effect, polymer waste removed from solid waste is classified as hazard class 4, except for PVC - hazard class 3.

P.0566 Influence of adrenaline and its precursors on the locomotor activity of paramecium caudatum as a new method of preclinical trials

P.0566 Influence of adrenaline and its precursors on the locomotor activity of paramecium caudatum as a new method of preclinical trials

The Brain as a Constructor: What Does the Visual Perception Has in Common With Language?

Halloysite nanotubes (HNTs) with immobilized gold (Au) nanoparticles (NPs) were explored to enhance photoheating of aqueous media under excitation by continuous wave (CW) and nanosecond pulsed lasers with wavelengths close to the plasmonic resonance of Au-NPs. The structure and plasmonic properties of HNTs/Au-NP nanocomposites were analyzed by means of the transmission electron microscopy and optical spectroscopy. A remarkable photothermal effect with initial temperature growth of about 0.5 °C/min was observed for HNTs/Au-NPs’ aqueous suspension under relatively low excitation intensity, while the same photoexcitation of bare HNTs’ aqueous suspension did not result in any noticeable heating. In vitro experiments with Paramecium caudatum unicellular organisms have revealed a strong suppression of the cell viability after photoexcitation. While the average photoheating effect did not exceed 3–4 °C, the cell viability was decreased multifold, especially for the pulsed photoexcitation. The experimental results are explained by the spatially and temporally localized photohyperthermia in the vicinity of Au-NPs. The observed photoheating of HNTs/Au-NP nanocomposite is promising for applications in antibacterial treatment and targeted cancer therapy.

БИОРАЗНООБРАЗИЕ ПЛЕСНЕВЫХ ГРИБОВ В РАЙОНАХ ГОРОДА ЧЕБОКСАРЫ

A study of 12 soil samples in the summer period in the districts of the city of Cheboksary was conducted. The aim of the research was to conduct a mycological analysis of the soil and isolate particularly dangerous micromycetes in the urban environment. Soil samples were taken from the Moskovsky, Kalininsky, Leninsky districts of Cheboksary and Marposadsky highway. The pH of the soil environment of the city of Cheboksary was: Embankment of the Moskovsky district – 7.67, Kirovsky – 7.23; Leninsky – 7.28; Marposadskoe highway – 7.51. In mycological analysis of soil samples on agarized media of Chapek, the highest concentration of micromycetes was recorded in soil samples from the Moskovsky district on the Embankment, where the concentration of fungi of the genus Aspergillus fumigates was 27 %, fungi of the genus Fusarium sporotrichioides and Fusarium graminearum was 15 %. The soil of the Leninsky district was dominated by fungi of the genus Penicillium, their concentration was 23 %, Aspergillus flavus – 18 %. Isolates of fungi of the genus Penicillium spp. were isolated in the soil of the Kalininsky district, and their concentration was – 7 %, Aspergillus flavus – 21 %. The soil from the Marpasad highway was dominated by fungi of the genus Mucor sp. Testing on Paramecium caudatum infusoria showed that the field isolate of Aspergillus fumigates had toxic properties, the evaluation criterion for biotesting was 38 %. Aspergillus flavus showed a 78 % survival rate when tested on infusoria.

Massive colonization of protein-coding exons by selfish genetic elements in Paramecium germline genomes.

Ciliates are unicellular eukaryotes with both a germline genome and a somatic genome in the same cytoplasm. The somatic macronucleus (MAC), responsible for gene expression, is not sexually transmitted but develops from a copy of the germline micronucleus (MIC) at each sexual generation. In the MIC genome of Paramecium tetraurelia, genes are interrupted by tens of thousands of unique intervening sequences called internal eliminated sequences (IESs), which have to be precisely excised during the development of the new MAC to restore functional genes. To understand the evolutionary origin of this peculiar genomic architecture, we sequenced the MIC genomes of 9 Paramecium species (from approximately 100 Mb in Paramecium aurelia species to >1.5 Gb in Paramecium caudatum). We detected several waves of IES gains, both in ancestral and in more recent lineages. While the vast majority of IESs are single copy in present-day genomes, we identified several families of mobile IESs, including nonautonomous elements acquired via horizontal transfer, which generated tens to thousands of new copies. These observations provide the first direct evidence that transposable elements can account for the massive proliferation of IESs in Paramecium. The comparison of IESs of different evolutionary ages indicates that, over time, IESs shorten and diverge rapidly in sequence while they acquire features that allow them to be more efficiently excised. We nevertheless identified rare cases of IESs that are under strong purifying selection across the aurelia clade. The cases examined contain or overlap cellular genes that are inactivated by excision during development, suggesting conserved regulatory mechanisms. Similar to the evolution of introns in eukaryotes, the evolution of Paramecium IESs highlights the major role played by selfish genetic elements in shaping the complexity of genome architecture and gene expression.

Gold nanoparticles immobilized on halloysite nanotubes for spatially-temporally localized photohyperthermia

Halloysite nanotubes (HNTs) with immobilized gold (Au) nanoparticles (NPs) were explored to enhance photoheating of aqueous media under excitation by continuous wave (CW) and nanosecond pulsed lasers with wavelengths close to the plasmonic resonance of Au-NPs. The structure and plasmonic properties of HNTs/Au-NP nanocomposites were analyzed by means of the transmission electron microscopy and optical spectroscopy. A remarkable photothermal effect with initial temperature growth of about 0.5 °C/min was observed for HNTs/Au-NPs’ aqueous suspension under relatively low excitation intensity, while the same photoexcitation of bare HNTs’ aqueous suspension did not result in any noticeable heating. In vitro experiments with Paramecium caudatum unicellular organisms have revealed a strong suppression of the cell viability after photoexcitation. While the average photoheating effect did not exceed 3–4 °C, the cell viability was decreased multifold, especially for the pulsed photoexcitation. The experimental results are explained by the spatially and temporally localized photohyperthermia in the vicinity of Au-NPs. The observed photoheating of HNTs/Au-NP nanocomposite is promising for applications in antibacterial treatment and targeted cancer therapy.

Parasitism and host dispersal plasticity in an aquatic model system.

Dispersal is a central determinant of spatial dynamics in communities and ecosystems, and various ecological factors can shape the evolution of constitutive and plastic dispersal behaviours. One important driver of dispersal plasticity is the biotic environment. Parasites, for example, influence the internal condition of infected hosts and define external patch quality. Thus, state-dependent dispersal may be determined by infection status and context-dependent dispersal by the abundance of infected hosts in the population. A prerequisite for such dispersal plasticity to evolve is a genetic basis on which natural selection can act. Using interconnected microcosms, we investigated dispersal in experimental populations of the freshwater protist Paramecium caudatum in response to the bacterial parasite Holospora undulata. For a collection of 20 natural host strains, we found substantial variation in constitutive dispersal and to a lesser degree in dispersal plasticity. First, infection tended to increase or decrease dispersal relative to uninfected controls, depending on strain identity, indicative of state-dependent dispersal plasticity. Infection additionally decreased host swimming speed compared to the uninfected counterparts. Second, for certain strains, there was a weak negative association between dispersal and infection prevalence, such that uninfected hosts dispersed less when infection was more frequent in the population, indicating context-dependent dispersal plasticity. Future experiments may test whether the observed differences in dispersal plasticity are sufficiently strong to be picked up by natural selection. The evolution of dispersal plasticity as a strategy to mitigate parasite effects spatially may have important implications for epidemiological dynamics.

The Survival of the Infusoria Paramecium caudatum in the Presence of Aluminum Oxide Nanoparticles

Acute toxicity of nanoparticles of aluminum oxide (Al2O3) with a size of 13–16 nm was investigated by the biotesting method using Paramecium caudatum ciliates in the concentration range of 10–100 μg/mL. Aluminum oxide has an acute toxic effect on paramecium at concentrations of 20–100 μg/mL. The mean lethal dose (LD50) is equal to the concentration of nanoparticles at which the mortality of ciliates in relation to the control reached 50%. The LD50 for Al2O3 nanoparticles is 23 μg/mL at a 24-h exposure. According to published data, the toxic effect of Al2O3 nanoparticles is specific and depends on the size and surface charge of the particles and on the interfacial interaction of nanoparticles with the cell surface, as well as on the concentration and exposure time.

Оценка функциональных свойств и показателей безопасности зернового хлеба с амарантовой мукой

Introduction. Various formulations of sprouted grain breads, including those with amaranth flour, were developed to combat food-related diseases. Healthy food industry requires thorough assessment procedures and hygienic practices. The research objective was to assess the functional properties and safety indicators of amaranth bread made from sprouted wheat grain.
 Study objects and methods. One day old grain bread was tested for antioxidant activity using amperometric method. Its glycemic index was determined according to the ratio of the area under the glycemic curve per bread sample to the area under the glycemic curve for pure glucose, expressed as a percentage. Crumb proteins digestibility was measured in vivo using ciliates Paramecium caudatum. Phytin content was measured by the colorimetric method, while safety indicators were compared to the Technical Regulations of the Customs Union No. 021/2011. Bound moisture content was determined with a refractometer after three days of storage according to the change in sucrose concentration. The number of mesophilic aerobic and facultative anaerobic microorganisms (NMAFAnM) was described based on State Standard 10444.15-94.
 Results and discussion. The amaranth flour slightly affected the antioxidant activity of the grain bread. It decreased the glycemic index by 8.3% and increased the microbiological purity by 1.4 times, raised the crumb proteins digestibility by 3.0%, reduced the phytin content by 7.0%, and slowed down the staleness process by 12 h. In terms of safety indicators, the obtained sample of amaranth grain bread met the TR CU 021/2011 requirements “On food safety”. The decrease in the glycemic index values could be explained by the lower activity of amylolytic enzymes in amaranth flour compared to sprouted wheat. The low digestibility of carbohydrates resulted from their effect on starch. The increase in digestibility and the decrease in phytin content were caused by the lower amount of dietary fiber. The high content of bound moisture explains the longer shelf life. Amaranth flour had lower microbiological contamination compared to wheat, which decreased the NMAFAnM.
 Conclusion. Amaranth flour had a positive effect on the functional properties of grain bread safety indicators, which makes it possible to include it into sprouted wheat grain products.

Surfactant-enhanced treatment of oil-contaminated Arctic tundra soil: Ecotoxicological assessment

During 2018–2019 summer expeditions to the Yamal peninsula, we collected tundra gley soil samples at the oil-contaminated sites. The contamination level was determined by fluorimetry and was ranged from 30 to 107 g/kg. The soil quality was evaluated by its enzymatic activity; the low catalase activity of the soils confirmed the presumed slow soil natural attenuation and the need for land remediation. The oil-contained and background samples were ex-situ treated with the aqueous solutions of non-ionic BOK-6 and anionic AddiMax PV01 synthetic surfactants. The treatment efficiency reached 71 ± 2% and 97 ± 3% in the experimental design with BOK-6 and AddiMax PV01, respectively. We derived the ecotoxicity endpoints for the surfactant solutions, using infusoria Paramecium caudatum Ehrenberg and higher plants Raphanus sativus L. and Avena sativa L. The protozoan mortality was studied and resulted in LC 50 − 24 values << 0.1 mg/L and 339 mg/L for BOK-6 and AddiMax PV01, respectively. Both surfactant solutions and surfactant residues in soil showed the inhibition potential towards higher plants. BOK-6, with a strong relation to its chemical and ecotoxic profile, completely inhibited seed germination in the treated soil. The less ecotoxic surfactant AddiMax PV01 inhibited plant growth by 38% compared to control. The treatment increased ecotoxicity and dehydrogenase activity and further lowered the catalase activity of the background soil, and, therefore, the surfactant residues migrating to the non-contaminated territories should be controlled. By this study, we show the efficiency of the surfactant-enhanced remediation of arctic soils, but the associated environmental risks must be addressed. • Ex-situ treatment of oil-contaminated tundra gley soil reached 69%–99% efficiency. • Enzymes activity indicated slow natural attenuation potential of arctic soil. • Residues of toxic surfactant could cause greater ecotoxic effect than contamination. • Surfactants residues inhibited biological activity of non-contaminated arctic soil.

Study of the biocidal properties of a new agent based on modified bee parchment

The problem of prevention and treatment of gastrointestinal diseases of infectious etiology of calves is still relevant. Recently, bee products (honey, bee venom, bee parchment, propolis, royal jelly) have been used for this purpose. Taking into account the unique properties of beekeeping products, we have developed a new biologically active agent based on modified bee parchment. The developed product is made by alkaline hydrolysis of 3-4 % solution of sodium hydroxide of bee parchment and contains a complex of biologically active substances. In order to accelerate the study of the effect of the developed product on living organisms, a model of using the ciliated protistic organism Paramecium caudatum, inhabiting freshwater reservoirs, was proposed. The aim of the study was to study the biocidal properties of the developed agent of the biological model. The study of the effect of a new agent based on modified bee parchment was carried out according to the methodological recommendations “Screening of bio-stimulating and biocidal substances (adaptogens, bactericides and other drugs)” on a model of a free-living infusoria slipper Paramecium caudatum. As a result of the study, it was found that the developed agent has pronounced biocidal properties (similar to widely used antibacterial drugs). In order to study the cytotoxic and ecotoxic effects of the developed medium, it is necessary to conduct a number of additional studies to determine their comprehensive effect on protistic organisms as a test laboratory model.

STUDY OF THE INFLUENCE OF THE INSECTICIDE CARBOPHOS CONTAINING MALATION ON THE BIOCENOSIS OF SOIL AND WATER

Background The article shows the influence of the insecticide Karbofos, the active ingredient of which is malathion, on soil and water biota. Various test organisms were used to determine the toxicity of the insecticide. Karbofos is used in the country's agriculture in the fight against various pests. Aims and Objectives The purpose of this work is to study the effect of the pesticide karbofos on soil and water biota: - determination of the toxic effect of the drug on seedlings of tomato seeds ( Solanum lycopersicum) , cucumber ( Cucumis sativus ) and wheat ( Triticum ); - study of the impact on the simplest aquatic organisms ciliates-shoes ( Paramecium сaudatum ); - study of the effect of the drug on earthworms ( Lumbricus terrestris L.) and microorganisms living in the soil; - study of the biodegradation of malathion using soil microorganisms. Methods The material for the experiments was the drug karbofos, in which the active substance is malathion, and the soil for the isolation of soil microorganisms capable of destroying the insecticide, selected in the ecologically clean territory of the Ufa region of the Republic of Bashkortostan. In the presented work, studies on phytotoxicity were carried out, the cultures of tomato ( Solanum lycopersicum ), cucumber ( Cucumis sativus ) and wheat ( Triticum ) were used as test objects; this preparation is often used in agriculture to treat these plants. Experiments to assess the toxicity of the insecticide to protozoan aquatic organisms were carried out on slipper ciliates ( Paramecium caudatum ). The research was carried out using BIOTESTER-2 device. Experiments on the effect of malophos on earthworms were carried out, taking into account their behavior, the condition of contact of earthworms ( Lumbricus sterrestris L .) with the drug was modeled. Determination of the number of microorganisms in the soil sample before and after exposure to insecticide at concentrations of 1 industrial concentration (IC), 2 IC and 5 IC was carried out by the method of «prints» in Petri dishes in beef-extract agar-agar, taken as a nutrient medium. Suspended soil samples were inoculated and cultivated for 2 to 5 days in a thermostat at a temperature of 28 °C. The microorganisms used malathion as a source of carbon and energy. The change in the destructive material was determined using a thin-layer chromatogram ( TLC ) using Silufol UV-254 plates, acetone as eluent, phosphoric-molybdic acid developer ( Rf = 0.5 ). Chromato-mass spectral analysis was performed on a Shimadzu GC-9A instrument. Results Experiments on the study of phytotoxicity showed that after treatment of seeds with the drug karbofos with different concentrations: IC, 2IC, 5IC and control (without the drug), the lengths of the aboveground and underground parts of plants that were etched differ from the lengths of the control -sample. The effect of the increasing dose is depressing in nature. Biotesting of the insecticide carbophos on infusoria-shoes showed that the toxicity index of the IC insecticide is 0.75 (group IV), therefore, the studied drug has a high degree of toxicity. The results of the analysis of the effect of the malathion-based insecticide on earthworms showed that the drug has a high toxic effect. In an experiment to establish the effect of an insecticide on soil bacteria, it was found that in the soil untreated with a toxicant, the microorganisms are dominated by Pseudomonas sp., Bacillus sp., Arthrobacter sp., Azotobacter sp., Flavobacterium sp. and Penicilium sp. The suppression and decrease in the number of microorganisms occurs already with IC. Contamination with 5 IC leads to the disappearance of Azotobacter sp., Arthrobacter sp. and Flavobacterium sp. from the soil microenvironment. The toxic effect of malathion is resisted by bacteria of the species Pseudomonas sp. and Bacillus. sp. Monitoring of the biodegradation of the studied drug, which was carried out using multinuclear 1H and 31P NMR spectroscopy, showed that the pesticide molecule practically does not undergo transformation even after 154 days.

Ciliofauna Species Wealth of the Khabarovsk Central City Pond

The paper describes the composition of the Ciliata species of the Khabarovsk Central Pond. In the course of the inventory, 43 Ciliata species belonging to 2 subtypes and 11 classes have been identified, the most numerous of which are Spirotrichea and Oligohymenophorea. Also, 20 species have not previously been recorded on the territory of the Middle Amur Region. By the frequency of occurrence, the vast majority of species (23 representatives) are observed in the solitary samples (up to 15 %). The background species include ciliates such as Coleps hirtus, Strombidium viride, Stylonychia mytilus complex, Paramecium caudatum, and Uronema marinum. It has been found that in the reservoir being studied, the average size (up to 200 μm) ciliates dominate. By the ecotope preferred, the ‘transitional’ cluster representatives prevail, which indicates the possible widespread colonization of the reservoir by protozoa. This is due to the shallow depth of the Central Pond and, therefore, the lack of clear boundaries between individual zones.

Biological activity of extracellular protease preparations of Aspergillus ochraceus micromycete on the Paramecium caudatum model

The research was carried out to study the biological activity of proteases of filamentous fungi, in particular the recombinant protease of Aspergillus ochraceus BMKF41040 micromycete, on a biological model of a unicellular organism - a culture of Paramecium caudatum ciliates. The test object Paramecium caudatum is characterized by a short life cycle, rapid reproduction, it is a convenient model for studying the response of an organism to the effects of preparations. The experiment consisted of 3 stages: rapid assessment of the biological activity of the recombinant protease of Aspergillus ochraceus BMKF41040 micromycete on the culture of infusoria in the stationary growth phase; the assessment of the biological effect of the studied object on the mechanisms of adaptation and cell resistance under the damaging effect of an unfavorable factor; the assessment of the biological activity of the studied objects by the reproduction intensity of ciliates. The results of the studies have shown that the recombinant protease of Aspergillus ochraceus BMKF41040 micromycete does not have a negative and stimulating effect on ciliates and does not affect their reproduction rate. It exhibits moderate biological activity in the test with the action of an unfavorable factor.

Nanowatt simple microcalorimetry for dynamically monitoring the defense mechanism of Paramecium caudatum

Microcalorimetry has been widely used in measuring cellular metabolic heat to study bioprocesses, such as metabolism. However, it is still limited by insufficient sensitivity and system complexity, especially for the direct measurements of individual cells. Here, we present a droplet-based simple differential microcalorimetric system for determining the real-time energy balance of the ciliate protist, Paramecium caudatum. We utilized the platform to dynamically monitor its defensive behavior and measured the temperature change. Then we used heat balance equation and calculated corresponding dissipated power and energy with an ultimate resolution of ≈14 nW. The results showed that the defensive behavior by the ejection of the trichocysts’ content consumed energy of ≈0.75 mJ per cell, and the dissipated power was ≈303.8 μW. This differential microcalorimetric platform can be used to study the metabolic heat of protist metabolism as well as other individual cells, helping us to understand this widespread, yet little-known, biological phenomenon from a new perspective.

In situ remediation efficacy of hybrid aerogel adsorbent in model aquatic culture of Paramecium caudatum exposed to Hg(II)

Silica-gelatin hybrid aerogel of 24 wt% gelatin content is an advanced functional material suitable for the high performance selective adsorption of aqueous Hg(II). The remediation efficacy of this adsorbent was tested under realistic aquatic conditions by exposing cultures of Paramecium caudatum to Hg(II) and monitoring the model cultures by time-lapse video microscopy. The viability of Paramecium was quantified by analyzing the pixel differences of the sequential images caused by the persistent movement (motility) of the cells. The viability of Paramecium displays a clear exposure-response relationship with Hg(II) concentration. Viability decreases with increasing Hg(II) concentration when the latter is higher than 125 μg L−1. In the presence of 0.1 mg mL−1 aerogel adsorbent, the viability of the cells decreases only at Hg(II) concentrations higher than 500 μg L−1, and 220 min survival time was measured even at 1000 μg L−1 Hg(II). The effective toxicity of Hg(II) is lower in the presence of the aerogel, because the equilibrium concentration of aqueous Hg(II) is low due to adsorption, thus Paramecium cells do not uptake as much Hg(II) as in the un-remediated cultures. Video imaging of Paramecium cultures offers a simple, robust and flexible method for providing quantitative information on the effectiveness of advanced materials used in adsorption processes for water treatment.