Sergei Piskov

Dr. Sergei Piskov

orcid

Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
7 February 2020 in Foods
Verified
Journal Article
Open access
PDF file
SPSergei Piskov
Sergei Piskov
LTLyudmila Timchenko
Lyudmila Timchenko
Wolf-Dieter Univ.-Prof. Dr. Dr. GrimmWolf-Dieter Univ.-Prof. Dr. Dr. Grimm
Wolf-Dieter Univ.-Prof. Dr. Dr. Grimm
IRIgor Rzhepakovsky
Igor Rzhepakovsky
SASvetlana Avanesyan
Svetlana Avanesyan
VKVladimir Kurchenko
Vladimir Kurchenko
In food biotechnology, Pleurotus ostreatus is of great interest as a source of natural antioxidants and angiotensin-converting enzyme (ACE) inhibitors. However, research in this area has not yet been completed. The effect of various drying methods on the structural properties and the rehydration capacity of mushrooms was investigated in this paper. The content of secondary metabolites, the peptide profile, and the antioxidative effect and ACE inhibitory activity of dry mushrooms were investigated in vitro, simulating the process of gastrointestinal digestion. X-ray microtomography has confirmed that structure of lyophilic and sun-dried mushrooms is dominated by open pores, and in mushrooms dried with hot air and microwave, closed pores. Experiments have shown that the conditions of freeze drying and sun drying of Pleurotus ostreatus provide a higher rehydration capacity of dried mushrooms. The maximum activity of radical absorption of the oyster mushroom after microwave drying was observed. The iron restoring capacity of the mushrooms is maximally maintained with microwave drying and hot-air drying. The properties of the antioxidant product with an emphasis on the high activity of inhibiting lipid oxidation of the mushroom maximized after drying in the sun. Mushrooms dried lyophilically and in the sun showed the highest ACE inhibitory activity.

24 January 2022 in Molecules
Verified
Journal Article
Open access
PDF file
IRIgor Rzhepakovsky
Igor Rzhepakovsky
DADavid A Areshidze
David A Areshidze
SASvetlana S. Avanesyan
Svetlana S. Avanesyan
WGWolf D. Grimm
Wolf D. Grimm
NFNatalya V. Filatova
Natalya V. Filatova
SPSergei Piskov
Sergei Piskov
Chlorophytum genus has been extensively studied due to its diverse biological activities. We evaluated the methanolic extract of leaves of Chlorophytum comosum (Green type) (Thunb.) Jacques, the species that is less studied compared to C. borivilianum. The aim was to identify phytoconstituents of the methanolic extract of leaves of C. comosum and biological properties of its different fractions. Water fraction was analyzed with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Nineteen compounds belonging to different chemical classes were identified in the methanolic extract of leaves of C. comosum (Green type) (Thunb.) Jacques. In addition to several fatty acids, isoprenoid and steroid compounds were found among the most abundant constituents. One of the identified compounds, 4′-methylphenyl-1C-sulfonyl-β-d-galactoside, was not detected earlier in Chlorophytum extracts. The water fraction was toxic to HeLa cells but not to Vero cells. Our data demonstrate that methanolic extract of leaves of C. comosum can be a valuable source of bioactive constituents. The water fraction of the extract exhibited promising antitumor potential based on a high ratio of HeLa vs. Vero cytotoxicity.

1 October 2022 in Agriculture
Verified
Journal Article
Open access
PDF file
SPSergei Piskov
Sergei Piskov
LTLyudmila Timchenko
Lyudmila Timchenko
SASvetlana Avanesyan
Svetlana Avanesyan
SSShahida Anusha Siddiqui
Shahida Anusha Siddiqui
MSMarina Sizonenko
Marina Sizonenko
Salam IbrahimSalam Ibrahim
Salam Ibrahim
Mushroom powders, as functional food ingredients, have attracted much attention in recent years. In the present study, four drying methods, i.e., freeze drying (FD), hot air drying (HAD), microwave drying (MWD), and sun drying (SD), were investigated to determine the effects on the structure and lipid profile of mushroom powder. The morphology of the mushroom powder was studied by using X-ray microtomography. The surface of the particles was studied by using scanning electron microscopy. The identification of lipophilic components was carried out by using gas chromatography in a powder extract obtained under in vitro conditions simulating digestion. The FD powder extract, with the widest range of particle size distribution (17.7–2270.3 µm), represented flake shapes with a porous structure. In addition, particles with minimal sizes (17.7–35.4 µm) were recorded only in the FD powder extract. Among the samples, the representation of large granules (1135.5–2270.3 µm) was ranked in the order: MWD < SD < FD < HAD, where the MWD sample was characterized by a narrow particle size composition (35.4–1135.1 µm), whereas the HAD granules were characerizedd by a lamellar structure with multiple deformations. The MWD particles were fused microaglomerates, whereas the SD powder consisted of amorphous particles with a strongly wrinkled surface. Sixty compounds were identified in the lipophilic powder extracts. Regarding the number of compounds identified, the powder extracts were ranked in the order MWD > FD > HAD > SD. Based on the content of linoleic acid, the samples were ranked in the order HAD < MWD < FD < SD, and, based on the stearic acid concentration, they were ranked in the order FD < HAD < MWD < SD. Oleic acid was identified in the HAD and MWD powder extracts, and palmitic acid was only identified in the SD powder extract. According to the number of fatty acid esters, the extracts were ranked in the order SD < FD < MWD < HAD. As per the concentration, alkanes were obtained from HAD and MWD samples and fatty alcohols were obtained from the FD samples. Lipophilic substances with a possible undesirable effect were identified only in the FD and HAD powder extracts. The results of this study expand the currently limited knowledge about the effect of various drying methods on the structural properties of mushroom (Pleurotus ostreatus) powder and its lipophilic component. The new information obtained will contribute to better management of mushroom raw materials in terms of optimization, taking into consideration the manufacturer’s interest in the technological and functional properties of mushroom powders as a food ingredient or biologically active substance for the production of nutraceuticals.

26 December 2022 in Sovremennye tehnologii v medicine
Verified
Journal Article
Open access
ISI.N. Schendrigin
I.N. Schendrigin
LTL.D. Timchenko
L.D. Timchenko
IRI.V. Rzhepakovsky
I.V. Rzhepakovsky
SAS.S. Avanesyan
S.S. Avanesyan
MSM.N. Sizonenko
M.N. Sizonenko
SPSergei Piskov
Sergei Piskov
Samples of synovial fluid from 95 patients with various joint pathologies at the stage of the disease progression characterized by copious effusion into articular cavities have been examined. Synovial fluid samples obtained by knee arthrocentesis served as a material for the investigation. Conventional methods were used to determine the concentration of uric acid, inorganic phosphorus, total protein, and amylolytic activity level in the selected samples while X-ray density was identified by computed microtomography. All samples of pathological joint fluid have shown a high level of amylolytic activity as compared to the synovial fluid from healthy joints. The relationship between the level of amylolytic activity in synovia and specific joint pathology has been identified. It has also been found that uric acid values, inorganic phosphorus concentrations, and total protein in various types of joint damage may influence X-ray density of the synovial fluid. Correlations between the studied indices have been established. New data on the level of synovia amylolytic activity has been obtained in one non-inflammatory and six different inflammatory diseases. Pathogenically determined correlation between the microtomographic index of synovial fluid density and concentrations of uric acid, inorganic phosphorus, total protein has been confirmed. Specific indicators of X-ray density of synovia in various joint pathologies as well as unidirectional and multidirectional data in comparison with the norm allow us to consider X-ray microtomography as a method that reveals additional details during investigation of synovial fluid density and brings new surrogate markers for the study of pathogenetic mechanisms of the development, differentiation, and treatment of various joint pathologies.

23 October 2024 in Agrarian science
Verified
Journal Article
Open access
PDF file
LTL. D. Timchenko
L. D. Timchenko
SPSergei Piskov
Sergei Piskov
MSM. Sh. Shakhbanov
M. Sh. Shakhbanov
IRIgor Rzhepakovsky
Igor Rzhepakovsky
MSM. N. Sizonenko
M. N. Sizonenko
MRMaksim B Rebezov
Maksim B Rebezov
Relevance. The positive aspects of disinfecting ozonation of hatching eggs allow us to expect successful application of the method not only in large but also in small-scale farms, as well as for experimental and industrial purposes in laboratories and bio-enterprises related to the technological process based on the incubation of a small number of eggs. This determines the importance of expanding the range of ozonizers due to numerous portable devices. There are no clear recommendations for these devices and this causes the need to search for the most effective and harmless modes for the embryo, and schemes of disinfecting ozonation.Methods. The study used fertilized chicken eggs “Hysex Brown” and a portable ozonizer “OZON-OviV”. Ozone concentration 2.0 mg / l. Eggs were treated in a specially made chamber. Technology-1: twice for 30 minutes before incubation and on the 3rd day of incubation. Technology-2: three times for 30 minutes before incubation, on days 3 and 5. The range of studies included: assessment of total microbial contamination (densitometry); identification of microorganisms (MALDI-TOF-spectrometry); biological control of incubation (fertility, hatchability, mortality, developmental abnormalities); assessment of the adequacy of the internal organs (MicroCT); embryo morphometry (weight, length, chest circumference) and calculation of development proportionality indices; histological assessment of the liver.Results. The total ozone concentration during treatment by two methods was 240 mg/l and 360 mg/l, respectively. The disinfecting efficiency of ozonation has been proven, providing a decrease in the level of total microbial contamination by 30% and 40% with double and triple treatment. A tendency to maintain a low total microbial contamination, compared to intact eggs, up to 14 days of incubation has been revealed. The dynamics of the microbial landscape indicate the bacteriostatic effect of ozone in the concentrations used on a wide range of microorganisms. Microtomographic and histological methods confirmed the harmlessness of the technologies used. Along with the more pronounced antibacterial effect of technology-2, the presence of a stimulating effect on the body of the developing embryo was revealed, which determines the preference for its choice.

21 March 2022 in RUDN Journal of Medicine
Verified
Journal Article
Open access
PDF file
NBNickolai G. Belyaev
Nickolai G. Belyaev
ELElvira D. Levochkina
Elvira D. Levochkina
VBVladimir A. Baturin
Vladimir A. Baturin
IRIgor Rzhepakovsky
Igor Rzhepakovsky
TATatyana V. Abasova
Tatyana V. Abasova
БГБеляев Н. Г.
Беляев Н. Г.
Relevance. Early diagnosis of chronic overstress among athletes remains an important problem for coaches and specialists in the field of sports physiology and medicine. The goal is to study in an animal model the dynamics of autoimmune response to physical activity of different duration and intensity and to establish the prospects of the method of determining autoantibodies to cardiomyocyte proteins as an indicator of the morphofunctional state of the heart in the conditions of adaptation to muscle loads. Materials and Methods. The study was conducted in male white rats. Animals were subjected to 9 weeks of training simulated with treadban. The intensity of the load changed the angle of inclination and the speed of the tape. The amount of cardiospecific autoantibodies (auto-AB) to troponin I, to alpha-actin 1, to the human cardiac beta-myosin heavy chain MYH7 was determined in the blood by enzyme immunoassay. The relative heart mass was measured. Histomorphological assessment of cardiomyocyte condition was carried out. Statistical processing was carried out using the Student and Mann-Whitney criteria. Results and Discussion. Animal training was accompanied by moderate cardiac hypertrophy of pathological changes in cardiomyocytes. Heart weight increased by 6.9 %; 10.6 %; 12.9 % in the dynamics of 6-8-9 weeks of training. Concentrations of auto-AB to troponin I and to alpha-actin 1 were characterized by cyclicity, manifested by an increase in week 2 and a decrease by the 8th and 9th weeks of training. In the dynamics of 0-2-8-9 weeks of the experiment, the amount of auto-AB to troponin I was: 3.10.3; 4.20.9; 2.10.2; 2.00.04 ng/ml. For auto-AB to actin: 26.71.2; 31.31.4; 13.71.8; 12.11.6 ng/ml, respectively. The level of auto-AB to beta-myosin was manifested by a decrease in the dynamics of 0-6-9 weeks of training and amounted to: 16.30.9; 10.91.5; 8.20.8; 9.6 0.9 ng/ml. Conclusion. The results of determining cardiospecific auto-AB demonstrate a clear response of the immune system to the processes taking place in cardiomyocytes, which makes it possible to recommend further study of the method of determining auto-AB to cardiomyocyte proteins as a diagnostic test of the functional state of the heart muscle during the period of adaptation to physical activity.