Varvara Stepochkina

Varvara Stepochkina


Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

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19 July 2022 in Separations
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Mayya RazgonovaMayya Razgonova
Mayya Razgonova
LTLyudmila Tekutyeva
Lyudmila Tekutyeva
АПАнна Подволоцкая
Анна Подволоцкая
VSVarvara Stepochkina
Varvara Stepochkina
AZAlexander Zakharenko
Alexander Zakharenko
Kirill Sergeevich GolokhvastKirill Sergeevich Golokhvast
Kirill Sergeevich Golokhvast
Three types of Zostera marina L. collection were extracted using the supercritical CO2-extraction method. For the purposes of supercritical CO2-extraction, old seagrass ejection on the surf edge, fresh seagrass ejection on the surf edge and seagrass collected in water were used. Several experimental conditions were investigated in the pressure range 50–350 bar, with the used volume of co-solvent ethanol in the amount of 1% in the liquid phase at a temperature in the range of 31–70 °C. The most effective extraction conditions are: pressure 250 Bar and temperature 60 °C for Z. marina collected in sea water. Z. marina contain various phenolic compounds and sulfated polyphenols with valuable biological activity. Tandem mass-spectrometry (HPLC-ESI–ion trap) was applied to detect target analytes. 77 different biologically active components have been identified in Z. marina supercritical CO2-extracts. 38 polyphenols were identified for the first time in Z. marina.

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EVElena Vasyutkina
Elena Vasyutkina
YYYulia Yugay
Yulia Yugay
VGValeria P. Grigorchuk
Valeria P. Grigorchuk
OGOlga V. Grishchenko
Olga V. Grishchenko
MSMaria Sorokina
Maria Sorokina
SYShkryl Yury
Shkryl Yury
Ipomoea batatas is a vital root crop and a source of caffeoylquinic acid derivatives (CQAs) with potential health-promoting benefits. As a naturally transgenic plant, I. batatas contains cellular T-DNA (cT-DNA) sequence homologs of the Agrobacterium rhizogenes open reading frame (ORF)14, ORF17n, rooting locus (Rol)B/RolC, ORF13, and ORF18/ORF17n of unknown function. This study aimed to evaluate the effect of abiotic stresses (temperature, ultraviolet, and light) and chemical elicitors (methyl jasmonate, salicylic acid, and sodium nitroprusside) on the biosynthesis of CQAs and cT-DNA gene expression in I. batatas cell culture as a model system. Among all the applied treatments, ultraviolet irradiation, methyl jasmonate, and salicylic acid caused the maximal accumulation of secondary compounds. We also discovered that I. batatas cT-DNA genes were not expressed in cell culture, and the studied conditions weakly affected their transcriptional levels. However, the Ib-rolB/C gene expressed under the strong 35S CaMV promoter increased the CQAs content by 1.5–1.9-fold. Overall, our results show that cT-DNA-encoded transgenes are not involved in stress- and chemical elicitor-induced CQAs accumulation in cell cultures of I. batatas. Nevertheless, overaccumulation of RolB/RolC transcripts potentiates the secondary metabolism of sweet potatoes through a currently unknown mechanism. Our study provides new insights into the molecular mechanisms linked with CQAs biosynthesis in cell culture of naturally transgenic food crops, i.e., sweet potato.

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LBLarissa Balabanova
Larissa Balabanova
ONOlga Nedashkovskaya
Olga Nedashkovskaya
N(Nadezhda Otstavnykh (Chernysheva)
Nadezhda Otstavnykh (Chernysheva)
MIMarina Isaeva
Marina Isaeva
OKOxana Kolpakova
Oxana Kolpakova
LTLiudmila Tekutyeva
Liudmila Tekutyeva
Advances in the computational annotation of genomes and the predictive potential of current metabolic models, based on more than thousands of experimental phenotypes, allow them to be applied to identify the diversity of metabolic pathways at the level of ecophysiology differentiation within taxa and to predict phenotypes, secondary metabolites, host-associated interactions, survivability, and biochemical productivity under proposed environmental conditions. The significantly distinctive phenotypes of members of the marine bacterial species Pseudoalteromonas distincta and an inability to use common molecular markers make their identification within the genus Pseudoalteromonas and prediction of their biotechnology potential impossible without genome-scale analysis and metabolic reconstruction. A new strain, KMM 6257, of a carotenoid-like phenotype, isolated from a deep-habituating starfish, emended the description of P. distincta, particularly in the temperature growth range from 4 to 37 °C. The taxonomic status of all available closely related species was elucidated by phylogenomics. P. distincta possesses putative methylerythritol phosphate pathway II and 4,4′-diapolycopenedioate biosynthesis, related to C30 carotenoids, and their functional analogues, aryl polyene biosynthetic gene clusters (BGC). However, the yellow-orange pigmentation phenotypes in some strains coincide with the presence of a hybrid BGC encoding for aryl polyene esterified with resorcinol. The alginate degradation and glycosylated immunosuppressant production, similar to brasilicardin, streptorubin, and nucleocidines, are the common predicted features. Starch, agar, carrageenan, xylose, lignin-derived compound degradation, polysaccharide, folate, and cobalamin biosynthesis are all strain-specific.

13 March 2023 in Proceedings of the Voronezh State University of Engineering Technologies
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IBI. V. Boyarineva
I. V. Boyarineva
АПАнна Подволоцкая
Анна Подволоцкая
VSVarvara Stepochkina
Varvara Stepochkina
ERE. O. Rochin
E. O. Rochin
Currently, there is a need to develop an assortment of low-lactose or lactose-free dairy products and plant-based products due to an increase in the number of consumers with lactase deficiency, allergic to cow's milk components, cholesterol problems, etc. For the development of plant and lactose-free bioproducts, it is possible to use various starter cultures enriched with probiotics. Various starter cultures were used in the work, propionic acid bacteria were used as a probiotic. The objects were lactose-free milk and vegetable bases: rice milk, oat milk and coconut milk; the control was selected milk. A comparative analysis of the fermentation process of various compositions of starter cultures enriched with propionic acid bacteria on various raw materials was carried out. The duration of fermentation of vegetable raw materials is 8-10 hours, the acid-forming activity of combined starter cultures is quite high. The number of viable cells of lactic acid and propionic acid bacteria in the obtained bioproducts has a high value and amounts to 107-108 K.O.E. /cm3. This confirms that the nutrient medium for the cultivation of selected starter compositions is favorable, the microflora of the starter composition develops harmoniously. Lactic acid microorganisms and propionic acid bacteria make it possible to obtain fermented biological products with a variety of taste characteristics inherent in a certain type of raw material. According to the results of the research, the developed starter compositions meet the requirements for starter cultures, have valuable technological properties that allow expanding the range of plant and lactose-free biological products.

8 December 2022 in Ecological genetics
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ADAnton I. Degtyarenko
Anton I. Degtyarenko
VSVarvara Stepochkina
Varvara Stepochkina
SYShkryl Yury
Shkryl Yury
Plant genetic modification in order to increase their tolerance to various abiotic stresses has been of exceptional importance in recent years. Heterologous expression of glycine betaine (GB) biosynthetic genes leads to increased salt and drought tolerance in various plant species by maintaining the osmotic balance with the environment and stabilizing the quaternary structure of complex proteins. However, GB biosynthesis in transgenic plants is limited by choline availability. Members of the Plumbaginaceae family accumulate -alanine betaine (AB) instead [1]. The synthesis of AB is not limited by the availability of choline, as it follows the methylation pathway of the aproteinogenic amino acid -alanine. For the first time, we have generated Nicotiana tabacum plants expressing the -alanine N-methyltransferase (LlBANMT) gene of Limonium latifolium. Transgenic plants were much less affected by such abiotic stresses as increased salinity, excessive illumination, and low temperature. The experimental Nicotiana tabacum lines had lower rates of chlorophyll degradation under stress conditions compared to the control plants. LlBANMT expression also resulted in less biomass loss under stress conditions, which was associated with higher activities of reactive oxygen species detoxification systems and healthier cell membranes. The presented data demonstrate for the first time the protective properties of LlBANMT heterologous expression and shed light on the mechanisms of its action.

8 December 2022 in Ecological genetics
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EVElena Vasyutkina
Elena Vasyutkina
YYYulia Yugay
Yulia Yugay
VGValeria P. Grigorchuk
Valeria P. Grigorchuk
OGOlga V. Grishchenko
Olga V. Grishchenko
VSVarvara Stepochkina
Varvara Stepochkina
SYShkryl Yury
Shkryl Yury
Ipomoea batatas is a root crop widely cultivated in South America, Africa, and Asia. This is also a source of caffeoylquinic acid derivatives (CQAs) with potential health-promoting benefits. Sweet potato genome carries two separate cellular T-DNA (cT-DNA) regions (IbT-DNA1 and IbT-DNA2). Especially, IbT-DNA2 contains five ORFs homologous to the Agrobacterium rhizogenes T-DNA, namely ORF13, ORF14, ORF17n, ORF18/ORF17n, and RolB/RolC proteins [1]. Unfortunately, presently there is insufficient information on IbT-DNA2 genes function in the physiological processes of sweet potatoes. In this study, expressional levels of the IbT-DNA2 genes and the effect of Ib-rolB/C overexpression were examined using I. batatas cell culture. We discovered that I. batatas cT-DNA genes were not expressed in callus, and abiotic stresses and chemical elicitors affected their transcriptional levels weakly. Additionally, two Ib-rolBC-transgenic cell lines have been established though Agrobacterium-mediated transformation of I. batatas callus cells. Overexpression of Ib-rolB/C gene reduced biomass accumulation of transgenic cell lines by 1.21.6 times and increased the CQAs content by 1.51.9-fold. To justify the metabolic fluctuations, the study also looked into the expression patterns of the major biosynthetic genes, namely bPAL, IbC4H, Ib4CL, IbHCT, and IbHQT. The obtained data demonstrated that the overexpression of the Ib-rolB/C reduced the IbPAL transcript but considerable increase in the transcript levels of the IbHQT. We propose that this result was obtained through as-yet-uncharacterized signaling pathways activated by RolB/RolC.