Gas-liquid Chromatographic Method Research Articles

THE PROBLEM OF REGULATING FUNGICIDES ON THE SKIN SURFACE FOR OCCUPATIONAL SKIN DISEASE IN AGRICULTURAL WORKERS’ RISK PREDICTION

The aim. To establish the norms of fungicides on the skin surface and predicting the risk of occupational skin pathology in agricultural workers to develop measures to prevent diseases caused by dermal exposure to pesticides. Materials and methods. The natural experiment was performed in accordance with modern requirements (European Food Safety Authority (2022), and the risk assessment was carried out according to the Recommendations (Approved by the Ministry of Health of Ukraine No. 324 issued on 13.05.2009) with different methods of spraying techniques: rod, air blast fan spraying, pre-sowing, aviation, knapsack treatment. 17 series of natural experiments were performed, and the air of the working zone area (n =56) and dermal exposure (n =56) were analyzed for each worker with different pesticide application methods. Quantitative determination of pesticide content was carried out by gas-liquid and high-performance liquid chromatography methods. The results were statistically processed using a package of licensed statistical programs MedStat v.5.2 (Copyright © 2003-2019) and Microsoft® Excel® for Microsoft 365 MSO. Results. It was established that there is pesticide contamination, mainly of the gloves of tank filling operators when preparing working solutions. No contamination of the skin surface was detected; only pesticide residues were present on the surface of the workers’ overalls. A comparison of the exposure dose in case of percutaneous exposure during the performance of technological operations with different methods of processing, dermal equivalents of Acceptable Operator Exposure Level of pesticide to workers’ skin (DE AOEL) and the allowable dermal dose for professional contingents (ADderm) and the hazard coefficients by dermal exposure (HCderm) showed that that dermal exposure during individual technological operations with different processing methods had a reliable difference between processing methods, but there is no difference within one application method. Conclusions. During the comparison of the hazard coefficients for dermal exposure, calculated according to different models, no significant difference was found between the risks calculated according to DE AOEL and ADderm for individual technological operations in various treatment methods, except for the operator who performed knapsack treatment and the risk calculated according to ADderm is significantly lower compared to the DE AOEL risk.

Fatty acid composition of two small fish in the Gyda River (Kara Sea Basin, Northwestern Siberia, Russia)

The fatty acid composition of the flesh of rainbow smelt (RS, Osmerus mordax) and ruffe (RF, Gymnocephalus cernuus), two small fish species inhabiting the Gyda River (Siberia, Russia), was assayed using a gas-liquid chromatographic method with an ionization detection system and high efficiency capillary columns. RS was found to be richer in the total fatty acid content than RF (21.5 vs. 7.07 mg g–1). The proportion of saturated fatty acids (SFA) was similar in the fish studied (29.2 % in RS and 29.6 % in RF) whereas the flesh of RS contained a higher proportion of monounsaturated fatty acids, MUFA (42.2 vs. 13.9 %), and a lower proportion of polyunsaturated fatty acids, PUFA (28.6 vs. 56.5 %) than RF. RS is rich in essential n-3 PUFAs (2610 and 2390 μg g–1 for docosahexaenoic and eicosapentaenoic acids, respectively). In RF, the atherogenic index (0.39) and thrombogenic (0.20) index were lower than in RS (0.59 and 0.27, respectively). The fatty acid profile of RS in the study area differed from that reported for the flesh of this species from a Canadian estuary probably due to substantial differences in the diet of RS in these habitats. A comparison among fish species from the Gyda River indicated that in terms of nutrition indices, RS has the highest similarity with the muksun Coregonus muksun while RF is closely related to the northern pike Esox lucius. Based on the results from this study, both RF and RS can be recommended for human consumption. In particular, RS may be used as a replacement for muksun, an overfished species, in the traditional diet of indigenous peoples in northwestern Siberia.

EVALUATION OF GREENNESS PROFILES OF VARIOUS DEVELOPED METHODS FOR THE DETERMINATION OF COMMONLY USED NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDs) IN ENVIRONMENTAL WATERS

Objective: In our study, it was aimed to make a comparative analysis of the environmental impact profiles of two approaches including Gas Chromatography (GC) and Liquid Chromatography (LC) methods, which are frequently used techniques for the determination of non-steroidal anti-inflammatory drugs (NSAIDs) and their metabolites in environmental water samples. Material and Method: The evaluation of the methods' environmental impact was performed using National Environmental Methods Index Label (NEMI), Analytical Eco-scale, Analytical GREEnness Metric (AGREE), and Green Analytical Procedure Index (GAPI). Result and Discussion: The routine analysis of NSAIDs in environmental waters is carried out, resulting in a significant volume of chemical waste. In recent times, there has been a growing significance attributed to environmentally conscious analytical methodologies and the evaluation of methodologies through a green lens to confront this challenge. There is no statistically significant difference in terms of environmental impact profile was observed between the two methods compared.

Variation of the rate of pesticides decomposition used together in the process of agricultural production.

The use of tank mixtures of pesticides makes it possible to increase the efficiency of chemical treatment. The aim of the study was to establish the relationship between the joint use of pesticides and the rate of decomposition of active substances. The study was carried out on the crops of spring wheat, spring barley, peas, spring rapeseed, seed potato. Chemical treatments were carried out with insecticides and fungicides - the insecticide (imidacloprid and λ-cyhalothrin), suspension concentrate; the fungicide (propiconazole), emulsifiable concentrate; the insecticide (imidacloprid), soluble concentrate; the fungicide (copper sulfate tribasic), suspension concentrate. Determination of residual amounts of active substances of pesticides was carried out using methods of gas-liquid chromatography and high-performance liquid chromatography. The acceleration of decomposition of the active substance - imidacloprid on pea crops and spring rapeseed was caused by the combined use of the insecticide (imidacloprid) and the fungicide (propiconazole). The use of the fungicide (copper sulfate tribasic) in a tank mixture with the insecticide (imidacloprid and λ-cyhalothrin) on potatoes caused a slowdown in the decomposition of the active substances imidacloprid and λ-cyhalothrin. Also, there was a change in the level of intake by plant of active substances in the first three hours after spraying, when using tank mixtures, in comparison with the separate use of compounds. The data obtained on the change in the rate of decomposition of active substances of pesticides, when they are used together in mixtures, indicate the need to continue research in this area. In this regard, it is important to study the dynamics of the decomposition of individual active substances of pesticides in plant tissues when they are used in tank mixtures, it is also necessary to conduct research using compounds most commonly used in agricultural production.

Determination of methoxypyrazines in dry wines

The quality of wine depends not only on the balance of volatile and non-volatile macro-components, but also on the content of micro-components contained in ng, such as methoxypyrazines. They form shades of green vegetables – peas, asparagus, which are undesirable in excess for grape wines. Due to extremely low concentrations and serious interference from the complex wine matrix, their direct quantitative analysis is difficult. The general opinion of the researchers indicates that the direct determination of methoxypyrazines by available chromatography methods is practically impossible. Therefore, as a sample preparation, various types of extraction concentration are mainly offered, providing for subsequent concentrate purification. The possibilities of different variants of the QuEChERS technology are evaluated. The information analysis suggests that QuEChERS preparation will be the most accessible and effective, which can then be easily combined with analysis by gas-liquid chromatography methods. Due to the volatility of methoxypyrazines, capillary GLC with a highly sensitive detector is proposed as the main method of analysis. Some advantage is given to multidimensional analysis: the use of a mass spectrometer in combination with a flame ionization detector shows higher reliability of the results. The use of a fairly simple but reliable flame ionization detector, which is able to ensure the reliability of measurements, is evaluated. In general, the approaches proposed by the researchers make it possible to ensure the necessary accuracy and quality of the quantitative determination of methoxypyrazines in wine samples.

NA

NA

Component composition and biological activity of essential oil of plant Zinnia elegans

By the method of steam distillation, samples of essential oil were obtained from a plant cultivated in the East Kazakhstan region. The essential oil was obtained with a yield in terms of air-dry raw materials. The method of gas-liquid chromatography carried out a quantitative analysis of the components of the essential oil. The quantitative content of essential oil components was calculated from the areas of gas chromatographic peaks without using correction factors. The main components of Zinnia elegans essential oil are α-terpineol, β-myrcene, myrtenal and camphene. Terpineol has a pleasant, lilac-like odor and is a common ingredient in perfumes, cosmetics, and fragrances. Pleasant smelling oily liquid. Myrcene has a large number of beneficial properties for the body, whether pure or in aromatherapy through the essential oils that contain it: Sedative and muscle relaxant, anti-inflammatory, interferon inhibition, gastric and duodenal ulcers, antalgic and antinociceptive, reduces sensitivity to pain by self-healing endogenous derivatives of morphine. Myrtenal - has an anti-inflammatory, resolving effect on acne, infiltrates. Increases the protective barrier of the epidermis. Antioxidant, rejuvenating. Camphene components are effective in the treatment of fungal, viral and bacterial infections that affect the respiratory system.

Separation potential of 1,5-pentanediol-based deep eutectic solvent: Infinite dilution activity coefficients and excess thermodynamic data

In the present study, the new data of the infinite dilution activity coefficient for 32 different solutes in {1-ethyl-1-methylpyrrolidinium bromide +1,5-pentanediol}, [[EMPYR] Br + 1,5-PDO] DES, were measured using the gas liquid chromatography (GLC) method with pre-saturation of the helium gas. The list of selected solutes included alkanes, alkenes, alkynes, cycloalkanes, cycloalkenes, aromatics, ketones, alcohols, and water. Because the solvents were volatile at the temperatures used for measurements, pre-saturation was deemed necessary. The measurements were taken at temperatures T = (313.15–343.15) K and atmospheric pressure. Values of partial molar properties, i.e., enthalpy, entropy, and Gibbs free energy, were computed at a reference temperature of Tref = 333.15 K. Moreover, the values of capacity and selectivity relating to [[EMPYR] Br + 1,5-PDO] DES for different sets of binary systems that are normally problematic in the separation through solvent extraction or distillation were also computed. These include cyclohexane/benzene; acetone/methanol; and hexane/benzene. The obtained data in the present work was then compared to the literature data, at similar temperatures. Thus, the thermodynamical data is important for pre-selecting solvents for industrial purposes.

Captan: Problems Associated with its Identification in Environmental Materials and Food Products. Potential Solutions

The study is devoted to identifying the ways in which captan can affect humans, including through the atmosphere and through food. The objects of the research were the following: the active substance (captan), air and a vegetable, namely sweet pepper. The equipment used included a chromato-mass-spectrometer «Agilent 5977А» with a gas chromatograph «Agilent Technologies-7890В», a liquid chromatograph «Agilent 1260» with a diode array detector and a liquid chromato-mass-spectrometer ExionLCAD/Qtrap 6500+. The method of gasliquid chromatography did not provide reproducible results, due to an unstable connection. Using techniques developed for the identification of captan in air, captan was determined using real samples collected during agricultural work. Captan content was reliably measured using samples taken from the air of the working environment (0,2 – 0,75 mg·m-3) and from the skin of operational staff (0,2 – 0,4 mg, using·wipes-1). In determining captan content in fruit and vegetable products, new and detailed methodological approaches were developed in order to minimise the matrix effect: a calibration curve was created based on the control matrix sample. The detection limit for captan was established at 0,01 mg·kg-1. In the analysis of actual sweet pepper samples, captan content was found to be below the detection limit.

ORGANOCHLORINE PESTICIDES POLLUTION OF THE BOTTOM SEDIMENTS OF NAKHODKA BAY AND PARTIZANSKAYA RIVER

Link for citation: Mazlova E.A., Blinovskaya Ya.Yu., Sokolova L.I., Tursunova G.Sh. Organochlorine pesticides pollution of the bottom sediments of Nakhodka bay and Partizanskaya river. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 9, рр. 25-35. In Rus. Relevance. The new data on the organochlorine pesticides pollution of the bottom sediments of Nakhodka bay and Partizanskaya river were obtained in 2020–2021. The objective of the article is to report the organochlorine pesticides pollution level of the bottom sediments and to define the possible sources of organochlorine pesticides in the marine environment. Techniques: sample collection of bottom sediments, Gas Chromatography Mass Spectrometry analysis of samples, Gas-liquid Chromatography method with electronic capture detector, statistical processing, assessment of the organochlorine pesticides contamination of sediments. Results. The new data were obtained on the organochlorine pesticides concentrations in Nakhodka bay in 2020–2021. The previous data on the studied area are described. The concentration of HCH pesticides (α- , β- and γ-HCH), DDT and its metabolites was analyzed. It was found that the concentration of α- , β- HCCH and DDT in bottom sediments increased in 2021.To determine the quality of bottom sediments, the average annual values of organochlorine pesticides concentrations in the bottom sediments gathered during the field works were compared with the quality guidelines. There are no approved quality guidelines for maximum permissible concentrations of pollutants in bottom sediments in the Russian Federation. For this reason, we used the quality guidelines applied in foreign countries («Dutch sheets» (Neue Niederlandische Liste. NNL) and Canadian quality standards for marine and estuarine bottom sediments (Canadian Sediment Quality Guidelines, CSQGs). Possible sources of organochlorine pesticides in the marine environment were analyzed. The results of this work showed that despite the ban on the use of these substances, these pesticides are included in the multiple compounds used in different industries and continue to enter and accumulate in the marine environment.

Content of fatty acids in lipids of adipose derived mesenchymal stem cells

The content of fatty acids in the lipids of mesenchymal stem cells of dog adipose tissue culture was studied. Mesenchymal stem cells of dog adipose tissue culture were obtained by culturing the primary material in a CO2 incubator with a content of 5 % CO2, at a temperature of 37 °C in DMEM medium with the addition of 10–15 % fetal bovine serum and 1 % antibiotic-antimycotic. When the confluency of the monolayer reached 70–80 %, the cells were transferred to a suspension and subcultivated in order to reduce the heterogeneity of the culture and obtain a sufficient amount of biological material. The lipids of the obtained stem cells were analyzed for the content of fatty acids by the method of thin-layer gas-liquid chromatography. Determination of the content of lipids of fatty acids in FSK of a cat was carried out by the Folch method. A mixture of fatty acid methyl esters was analyzed on a Trace GC Ultra gas chromatograph with a flame ionization detector on a capillary column SPTM –2560, 100 m x 0.25 mm ID, 0.20 μm film (Supelco). Identification of fatty acids was carried out using a standard sample of Supelco 37 Сomponent FAME Mix. Quantitative assessment of the LC spectrum was carried out by the method of normalization of the peak planes of methylated LC derivatives and their content was determined as a percentage of the total content of all LC. The conducted study of the content of fatty acids in lipids made it possible to reveal certain features of the lipid metabolism of mesenchymal stem cells cultured in dog adipose tissue. A high content of oleic acid, characteristic of cells resistant to apoptosis and with high proliferative potential, was determined; a high ratio of unsaturated linoleic to saturated stearic acid (С18:1/С18.0), which reflects the high activity of the stearoyl-coenzyme-desaturase enzyme and, indirectly, the active state of the Wnt/β-catenin signaling pathway; inability to lengthen the chain of saturated fatty acids; lack or low activity of de novo synthesis of omega-6 polyunsaturated fatty acids. 18 fatty acids were found in the composition of lipids of fetal stem cells of a cat, of the saturated ones - the most palmitic acid (33.70 ± 0.02 %), of the monounsaturated ones – oleic acid (21.63 ± 0.03 %), of the polyunsaturated ones – linoleic acid (6.45 ± 0.07 %). The least amount of cis-,11,14-eicosadienoic acid (0.04 ± 0.01 %) was found in the composition of cell lipids. The total amount of saturated fatty acids in dog mesenchymal stem cell lipids was 65.65 ± 0.02 %), unsaturated fatty acids – 34.35 ± 0.02 %. Monoene fatty acids were determined in the amount of 24.46 ± 0.02 %, and polyene – 9.89 ± 0.02 %. The ratio index of polyunsaturated fatty acids ω 3 to ω 6 is 0.40. Lipids of mesenchymal stem cells of adipose tissue culture were characterized by a lower content of monoene unsaturated fatty acids 24.46 ± 0.02; (P < 0.05), with a higher content of ω3 fatty acids 3.04 ± 0.02 %; (P < 0.05), with a lower content of ω6 fatty acids 6.86 ± 0.02 %; (P < 0.05) in contrast to lipids of red bone marrow stem cells.

QUALITY CONTROL OF TRANSFORMER OIL BY GAS-LIQUID CHROMATOGRAPHY

In oil-filled high-voltage equipment (power transformers, reactors, current and voltage transformers, switches and bushings), transformer oil performs a number of important functions (heat-removing, insulating, arcing, protective, information and diagnostic). With prolonged use in equipment, the oil undergoes oxidation, which leads to a deterioration in its dielectric properties. In order to slow down the process of oil oxidation and extend the life of liquid insulation, an antioxidant additive ionol (2,6-di-tert-butyl-4-methylphenol) is added to it. Using the method of chromato-mass spectrometry, it was found that ionol decomposes during its consumption with the formation of other phenolic-type compounds, which also exhibit antioxidant activity. In addition, the identified degradation products of ionol can serve as indicators of the state of the liquid insulation as a whole. However, the method of chromatomass spectrometry, for certain reasons, is not used in power grid laboratories. Therefore, in this paper, we propose a method for determining the decomposition products of ionol in their joint presence in operating oil, based on the method of gasliquid chromatography with a flame ionization detector. The implementation of this technique does not require significant investments. In addition, new boundary values of ionol have been established, which should be taken into account when planning the addition of ionol to operating oil in order to prevent a sharp deterioration in its insulating properties.

Research progress on preparation technology and detection methods of vanillin

Vanillin is an important spice, widely used in food, beverage, daily necessities, medicine and other fields. In this paper, the research progress of preparation techniques chemical synthesis, plant extraction and biotransformation of vanillin was reviewed. The detection methods of vanillin such as gas chromatography, liquid chromatography and electrochemical method were summarized, which provide reference for the development and research of vanillin in the future.

Measurement of Activity Coefficients at Infinite Dilution for Various Organic Solutes in Deep Eutectic Solvent (1-Butyl-2,3-dimethylimidazolium Chloride + Ethylene Glycol) at Different Temperatures

Activity coefficients at infinite dilution (γ13∞) for organic solutes in deep eutectic solvent (DES) prepared by {1-butyl-2,3-dimethylimidazolium chloride (BDMIM Cl) + ethylene glycol (EG)} at a molar ratio of 1:3 have been measured using the gas–liquid chromatographic method (GLC). The thermal stability of the entrainer was determined by the thermogravimetric analyzer. The measurements were carried out in the temperature range of T = (313.15 to 343.15) K and at atmospheric pressure. The values of the partial molar excess enthalpies at infinite dilution (H1E,∞) were derived from the temperature dependence of the γ13∞∞ values. The entropies (Tref ΔS1E,∞) and Gibbs energies (ΔG1E,∞) of organic solutes at a reference temperature Tref = 323.15 K were also calculated from the γ13∞ values. These excess thermodynamic functions were calculated to further explain the intermolecular interactions occurring between the volatile organic solvents and the prepared deep eutectic solvent. Important separation parameters such as selectivities (Sij∞) and capacities (Kj∞) at infinite dilution were computed from the activity coefficients at infinite dilution data at T = 313.15 K. Selectivity and capacity data were calculated for the industrial mixtures such as cyclohexane/benzene, hexane/thiophene, cyclohexane/ethanol. There results were compared to the literature data comprising deep eutectic solvents and ILs with the cation of 1-butyl-3-methylimidazolium. The investigated solvent was found suitable to separate azeotropes formed by alkanes/alcohols.

Hydrogermylation of allylsilanes and -germanes

The reactions of hydrogermylation of allylsilanes and -germanes R3MAll (M = Si, Ge; R = Cl, EtO, Me) by hydridgermanes R3GeH (R = Cl, Me) and trichlorogermane ether 2Et2O·HGeCl3 were studied. It has been established that small amounts of mono- (β- and γ-adducts) and double germylation products and, mainly, polymers are formed in reactions with ether. During hydrogermylation of Me3SiAll with trichlorogermane, insignificant amounts of β-adduct were recorded, but mainly in the entire series of experiments with Cl3GeH, γ-adducts are formed. In the catalytic reactions of allylsilanes and -germanes with trimethylgermane, exclusively γ-adducts are formed regardless of the framing of silicon and germanium atoms. A scheme of the possible course of the studied reactions is proposed. The identification of synthesized compounds was carried out using the methods of gas-liquid chromatography, 1Н, 13С NMR spectroscopy and chromatography-mass spectrometry

Development and approbation of an analytical method for the quantitative determination of carbon tetrachloride in freons used in the composition of medicines in the form of an aerosol

Aim to develop and test an analytical method for the quantitative determination of carbon tetrachloride in freons used in the composition of medicines in the form of an aerosol.
 Material and methods. Carbon tetrachloride (tetrachloromethane, Freon-10) - CCl4, M.m. = 153.81, heavy, colorless, volatile liquid with a sweet smell reminiscent of chloroform. Melting point - 22.96 С, boiling point - 76.75 C, relative density at 20 - [d]420 1.595. Poorly soluble in water (0.5 g/l), unrestrictedly miscible with alcohol, ether, acetone, benzene (chemically pure grade).
 To determine the tests for the presence and quantitative determination of carbon tetrachloride in propellant gases used in medicinal preparations, we chose the drug "Salbutamol-Pharmstandard". To identify and quantify carbon tetrachloride in propellants used in medicinal products, the gas-liquid chromatography method with electron capture detection with a capillary column was applied.
 Results. The developed method was used to determine carbon tetrachloride in the test preparation "Salbutamol". The results were statistically processed and showed that the content of carbon tetrachloride in the test preparation was 0.01580.0007 mg/l. The error of a single experiment with a confidence probability P = 95% was 4.42%
 Conclusion. We proposed a method for estimating the content of carbon tetrachloride impurities in aerosol dosage forms by gas-liquid chromatography with an electron capture detector. The technique involved the gas chromatographic separation of a sample, taken from an aerosol can, on a capillary chromatographic column. The most appropriate detector in this case turned out to be an electron capture detector.

N-Acetylcysteine Decreases Myocardial Content of Inflammatory Mediators Preventing the Development of Inflammation State and Oxidative Stress in Rats Subjected to a High-Fat Diet.

Arachidonic acid (AA) is a key precursor for proinflammatory and anti-inflammatory derivatives that regulate the inflammatory response. The modulation of AA metabolism is a target for searching a therapeutic agent with potent anti-inflammatory action in cardiovascular disorders. Therefore, our study aims to determine the potential preventive impact of N-acetylcysteine (NAC) supplementation on myocardial inflammation and the occurrence of oxidative stress in obesity induced by high-fat feeding. The experiment was conducted for eight weeks on male Wistar rats fed a standard chow or a high-fat diet (HFD) with intragastric NAC supplementation. The Gas-Liquid Chromatography (GLC) method was used to quantify the plasma and myocardial AA levels in the selected lipid fraction. The expression of proteins included in the inflammation pathway was measured by the Western blot technique. The concentrations of arachidonic acid derivatives, cytokines and chemokines, and oxidative stress parameters were determined by the ELISA, colorimetric, and multiplex immunoassay kits. We established that in the left ventricle tissue NAC reduced AA concentration, especially in the phospholipid fraction. NAC administration ameliorated the COX-2 and 5-LOX expression, leading to a decrease in the PGE2 and LTC4 contents, respectively, and augmented the 12/15-LOX expression, increasing the LXA4 content. In obese rats, NAC ameliorated NF-κB expression, inhibiting the secretion of proinflammatory cytokines. NAC also affected the antioxidant levels in HFD rats through an increase in GSH and CAT contents with a simultaneous decrease in the levels of 4-HNE and MDA. We concluded that NAC treatment weakens the NF-κB signaling pathway, limiting the development of myocardial low-grade inflammation, and increasing the antioxidant content that may protect against the development of oxidative stress in rats with obesity induced by an HFD.

DETECTION OF FALSIFICATION OF BUTTER BY COLORIMETRIC METHOD USING SMARTPHONE AND CHEMOMETRIC ANALYSIS

The paper proposes a simple and affordable way to identify and authenticate butter by a colorimetric method using a smartphone and chemometric analysis. Identification and authentication of dairy products was carried out by an analytical signal in the RGB colorimetric system when registering the intrinsic fluorescence of samples due to exposure to monochromatic ultraviolet light (365 nm). A test device based on a smartphone and a method for measuring colorimetric parameters in an additive RGB system for identifying and authenticating declared products of dairy origin are proposed. When studying colorimetric characteristics, iPhone X and iPhone XIII smartphones (Apple, USA) equipped with specialized RGBer software were used as a color recording device. The processing of the data array (for three variables R, G, and B) was carried out using the XLSTAT software product. The method of principal components and hierarchical cluster analysis were used to separate the samples by species (source of raw materials). Approbation of the presented approach was carried out on samples of commercially produced butter (32 samples) purchased in retail stores. The use of chemometric analysis methods made it possible to confirm the authenticity of the butter and reveal the facts of falsification. The results obtained correlated with the data of the arbitration method of gas-liquid chromatography in assessing the fatty acid composition of the fatty phase of the product. The proposed approach and its technical solution are characterized by the availability of component materials and digital equipment used in the operation of the test device. In addition, the mobility of the system and the ease of recording the colorimetric characteristics of the fluorescence of the analyzed object, combined with the clarity of the presented final information obtained using chemometric algorithms, makes this direction promising in monitoring laboratory and personal studies. For citation: Amelin V.G., Shogah Z.А.C., Bol’shakov D.S., Tretyakov A.V. Detection of falsification of butter by colorimetric method using smartphone and chemometric analysis. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 2. P. 53-61. DOI: 10.6060/ivkkt.20236602.6717.

Chemical characterization, anti-nociceptive and anti-inflammatory activities of Plukenetia conophora seed oil in experimental rodent models

Ethnopharmacological relevanceThe seed of the African walnut, Plukenetia conophora Mull.-Arg is well-known for its nutritional and medicinal values. The seed oil is widely used in massages to relieve pain, as nerve tonic and to enhance sexual performance. ObjectiveThe study aimed at investigating the chemical profile, antinociceptive and anti-inflammatory activities of P. conophora oil (PCO). MethodsSeed oil of P. conophora was characterized using Gas-Liquid Chromatographic method (GC-MS) and oral acute toxicity evaluated at 2000 mg/kg. Antinociceptive effects were evaluated in hot plate, acetic acid and formalin-induced paw licking tests. The anti-inflammatory effects were investigated in egg albumin and carrageenan-, formalin and complete Freund adjuvant (CFA)-induced paw oedema models. The levels of pro-inflammatory cytokines in the fluid exudates were also evaluated in carrageenan air pouch model. ResultsPCO exhibited high content of alpha linolenic acid (ALA). No toxicity was observed at 2000 mg/kg of PCO. PCO (50–200 mg/kg) demonstrated significant anti-nociceptive activity in pain models. PCO exhibited anti-inflammatory activity against oedema formation by phlogistic agents. The increased inflammatory oedema and oxidative stress in CFA-treated rats were also attenuated by PCO. The PCO (100 and 200 mg/kg) significantly reduced the levels of TNF-α (59.3% and 85.2%) and IL-6 (27.5% and 72.5%) in carrageenan-induced air pouch model. ConclusionThe results of this study suggest that ALA-rich seed oil of Plukenetia conophora demonstrated anti-nociceptive and anti-inflammatory activities via inhibition of pro-inflammatory cytokines and oxidative stress, lending supportive evidences for its use in painful inflammatory conditions.

Robust statistical analysis to predict and estimate the concentration of the cannabidiolic acid in Cannabis sativa L.: A comparative study

Growing awareness of the medicinal and therapeutic benefits of cannabis has resulted in extensive research, increasing numbers of commercial growers, and the provision of commercial testing. For commercial production, the importance of monitoring for consistent cannabinoid composition is essential. Gas chromatography and/or liquid chromatography methods are effective methods. Unfortunately, they are not easily scaled up for frequent or large-scale testing. Precision cultivation for medicinal cannabis requires the industry to test large volumes of plants frequently during different stages of the growth cycle. This cannot be achieved with destructive testing alone. A statistical method with 1H nuclear magnetic resonance (NMR) is proposed and investigated to explore its potential for a cost-effective mass-screening method of plant material samples. In addition, hyperspectral imaging (HSI) is employed for frequent non-destructive measurements. This allows increasing the frequency of observations during the growth of the plant. The cannabidiolic acid (CBDA) concentration is determined by the application of both HSI and NMR spectroscopy and validated against liquid chromatography-mass spectrometry (LCMS). The paper proposes a multivariate statistical regression algorithm that automatically determines the CBDA concentration directly from bucket integration of the NMR spectrum. The algorithm successfully predicted the CBDA concentration of 7 unknown samples from data selected from 4 known samples, with an average R2 value of 0.98. The proposed statistical method was applied to the data collected for HSI. It showed that while the hyperspectral dataset can be correlated with CBDA concentration, it was subject to high variance. However, HSI retains the spatial information of the actual plant structure, allowing the CBDA prediction to be mapped back to the original spatial location in the plant while providing visual information on CBDA concentration within a flower or leaf without requiring the plant component to be destroyed in the process.