Krum Ventsislavov Badarov

Dr. Krum Ventsislavov Badarov


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

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

Representative Publications

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1 December 2019 in Food and Chemical Toxicology
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Journal Article
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Dimitrina Zheleva-DimitrovaDimitrina Zheleva-Dimitrova
Dimitrina Zheleva-Dimitrova
Rumyana SimeonovaRumyana Simeonova
Rumyana Simeonova
RGReneta Gevrenova
Reneta Gevrenova
YSYonko Savov
Yonko Savov
VBVessela Balabanova
Vessela Balabanova
NDNikolay Danchev
Nikolay Danchev

1 September 2018 in Journal of Pharmaceutical and Biomedical Analysis
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Journal Article
Open access
RGReneta Gevrenova
Reneta Gevrenova
KBKrum Ventsislavov Badarov
Krum Ventsislavov Badarov
SBSabine Bouguet-Bonnet
Sabine Bouguet-Bonnet
YVYulian Voynikov
Yulian Voynikov
VBVessela Balabanova
Vessela Balabanova
MHMax Henry
Max Henry
Glucuronide Oleanane-type Triterpenoid Carboxylic Acid 3, 28-Bidesmosides (GOTCAB) saponins are bioactive natural compounds spread in Caryophyllidae. The high complexity of GOTCAB occurring as closely related isobaric and positional isomers is a challenge in their separation and identification. A new liquid chromatography - high resolution Orbitrap mass spectrometry acquisition strategy would be important for the structural elucidation of GOTCAB in plant extracts. In this study, the fragmentation behaviors of GOTCAB from methanol-aqueous root extract of Gypsophila glomerata Pall ex M. B. (Caryophyllaceae) were investigated using ultra high-performance liquid chromatography (UHPLC) coupled with hybrid quadrupole-Orbitrap high resolution mass spectrometry (HRMS). A new saponin was isolated and its structure was established by 1D and 2D-NMR spectroscopic experiments as 3-O-β-D-galactopyranosyl-(1→2)-[α-L-arabinopyranosyl-(1→3)]-β-D-glucuronopyranosyl gypsogenin 28-O-α-L-arabinopyranosyl-(1→3)-[β-D-xylopyranosyl-(1→4)]-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl ester. On the basis of the accurate mass measurements, fragmentation patterns in MS/MS analyses and comparison with previously isolated authentic references, a total of 41 GOTCAB saponins were identified or tentatively elucidated in G. glomerata roots, including 14 pairs of isobars. Possible fragmentation pathways for three groups of GOTCAB are suggested. The group I appeared to be GOTCAB of gypsogenin with two carbohydrate chains: a branched trisaccharide at C-3 and tri- to hexa-saccharide attached to C-28 of the aglycone through a deoxyhexose residue. Saponins with monoacetylated (group II) or sulphated (group III) C-28 chain were evidenced, as well as quillaic and oleanolic acid GOTCAB. Sixteen GOTCAB were previously not described. The content of Gypsophila prosaponins, gypsogenin 3-O-glucuronide (7.4079 ± 0.0723 mg/g dry weight, dw) and quillaic acid 3-O-glucuronide (4.4593 ± 0.1207 mg/g dw), was determined by solid phase extraction - high-performance liquid chromatography (SPE-HPLC). In this study is presented the first systematic investigation on the fragmentation patterns and diagnostic fingerprints of the fragment ions in the MS/MS spectra of the gypsogenin -, quillaic acid - and oleanolic acid - bidesmosides. A LC-HRMS Orbitrap acquisition strategy could give an insight in the GOTCAB containing taxa.

1 October 2021 in Journal of Ethnopharmacology
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Journal Article
Closed access
MDMartin Dimitrov
Martin Dimitrov
IIIvan Angelov Iliev
Ivan Angelov Iliev
KBKrum Ventsislavov Badarov
Krum Ventsislavov Badarov
DGDimitrina Georgieva
Dimitrina Georgieva
TTTeodora Todorova
Teodora Todorova

10 March 2022 in Applied Sciences
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Journal Article
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Ivanka TenevaIvanka Teneva
Ivanka Teneva
Tsvetelina Georgieva BatsalovaTsvetelina Georgieva Batsalova
Tsvetelina Georgieva Batsalova
KBKrum Ventsislavov Badarov
Krum Ventsislavov Badarov
Dzhemal MotenDzhemal Moten
Dzhemal Moten
Balik DzhambazovBalik Dzhambazov
Balik Dzhambazov
The filamentous cyanobacteria from genus Phormidium are rich natural sources of bioactive compounds that could be exploited as pharmaceuticals or nutraceuticals. In this study, we suggest a novel approach for assessing the immunomodulatory properties of the products derived from cyanobacteria. The influence of Phormidium papyraceum extract on the human leukocyte immunophenotype was evaluated by attempting to link this activity to certain putative compounds identified in the extract. By using three staining panels and flow cytometry, we found that the cyanobacterial extract affected mainly CD4+ T cells upregulating activated CD4+CD152+ T cells (15.75 ± 1.93% treated vs. 4.65 ± 1.41% control) and regulatory CD4+CD25+ T cells (5.36 ± 0.64% treated vs. 1.03 ± 0.08% control). Furthermore, P. papyraceum extract can modulate T cell subpopulations with a CD4+ effector/memory phenotype. Extract-treated cells showed increased production of IL-2 (55 ± 12 pg/mL) and IL-6 (493 ± 64 pg/mL) compared to the untreated, 21 ± 7 pg/mL and 250 ± 39 pg/mL, respectively. No significant changes were observed in the secretion of TNF-α. In addition, P. papyraceum extract displayed antibacterial activity against both Gram-negative (inhibition zone from 18.25 ± 0.50 mm to 20.28 ± 1.50 mm) and Gram-positive (inhibition zone from 10.86 ± 0.85 mm to 17.00 ± 0.82 mm) bacteria. The chemical profile of the cyanobacterial extract was determined using LC–ESI–MS/MS analysis, where at least 112 putative compounds were detected. Many of these compounds have proven different biological activities. We speculated that compounds such as betulin and the macrolide azithromycin (or their analogues) could be responsible for the immunomodulatory potential of the investigated extract. More studies are needed to determine and validate the biological activities of the determined putative compounds.

Verified
Journal Article
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Ivanka TenevaIvanka Teneva
Ivanka Teneva
KBKrum Ventsislavov Badarov
Krum Ventsislavov Badarov
Tsvetelina Georgieva BatsalovaTsvetelina Georgieva Batsalova
Tsvetelina Georgieva Batsalova
Dzhemal MotenDzhemal Moten
Dzhemal Moten
Balik DzhambazovBalik Dzhambazov
Balik Dzhambazov
Cyanobacteria of the genus Phormidesmis are recognized as a promising source of biologically active secondary metabolites with anticancer and immunomodulatory properties. In the present study, we investigated both the cytotoxic and immunological effects of an extract obtained from Phormidesmis molle PACC (Plovdiv Algal Culture Collection) 8140 as well as its chemical composition. The extract was profiled by LC-ESI-MS/MS (Liquid chromatography—electrospray ionization—tandem mass spectrometry), and selected compounds were evaluated with in silico ADMET (Absorption, distribution, metabolism, excretion and toxicity) modeling. The cytotoxic potential of the extract was evaluated in vitro using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay on human colorectal adenocarcinoma cell lines (Caco-2, HT-29, and LS-180). The immunological impact of the extract was assessed on human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. PBMCs were treated with 100 µg/mL extract for 48 h, followed by flow cytometric immunophenotyping and ELISA (Enzyme-linked immunosorbent assay)-based cytokine quantification. The extract induced a concentration- and time-dependent decrease in cancer cell viability after 24, 48, and 72 h of exposure. At 72 h, treatment with the highest concentration (200 µg/mL) reduced cell viability to 74% in Caco-2 cells, 69–70% in HT-29 cells, and 59–61% in LS-180 cells. Morphological changes observed after treatment with Phormidesmis extract showed pronounced cytotoxic and apoptosis-related effects in the colorectal cancer cell lines tested. Immunophenotyping revealed a pronounced expansion of natural killer (NK) cells (CD56+ and/or CD16+). CD3−CD56−CD16+ NK population was markedly increased (from 67.7 ± 0.95% in non-treated PBMCs to 94.66 ± 0.90% in extract-treated PBMCs, p < 0.001). In contrast, the proportions of CD8+ T cells, CD19+ B cells, and CD11b+ monocytes were significantly reduced (from 21.5 ± 4.50% to 7.22 ± 0.41%, from 11.9 ± 1.70% to 6.06 ± 0.42%, and from 66.4 ± 0.60% to 34.4 ± 0.87%, respectively). Cytokine analysis demonstrated strong suppression of Th1-associated cytokines, with significantly reduced interferon gamma (IFN-γ, 461 ng/mL in controls vs. 84 ng/mL in extract-treated cultures) and tumor necrosis factor alpha (TNF-α) levels (169 ng/mL in controls vs. 32 ng/mL in extract-treated cultures), whereas nterleukin-6 (IL-6) was moderately elevated (from 158 ng/mL in controls to 234 ng/mL in extract-treated cultures) and IL-10 remained low. These findings demonstrate that P. molle extract combines cytotoxic activity against cancer cells with potent immunomodulatory effects, highlighting its potential as a source of bioactive compounds for immune-based therapeutic strategies.

19 November 2024 in Preprints.org
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KBKrum Ventsislavov Badarov
Krum Ventsislavov Badarov
EDEvelina Daskalova
Evelina Daskalova
EAElena Apostolova
Elena Apostolova
GYGalina T. Yahubyan
Galina T. Yahubyan
Gergana ZahmanovaGergana Zahmanova
Gergana Zahmanova
IMIvan Minkov
Ivan Minkov
Resurrection plants are incredibly tolerant to drought. When dried out, they temporarily halt photosynthesis and respiration while protecting cellular structures. Upon rehydration, they rapidly resume normal function, allowing their cells and tissues to become re-energized. Nucle-otides play a crucial role as energy and information carriers in all living organisms. However, the dynamics and functioning of these vital compounds in resurrection plants have not been exten-sively studied. Nucleotide, nucleoside, and nucleobase extraction and analysis are technically challenging, so improved methods are of continued interest, especially techniques that can dis-tinguish the nucleotides’ degree of phosphorylation. Here, we describe an accurate mass, high-resolution hydrophilic interaction chromatography (HILIC-LC-hrMS/MS)- based method for quantitative profiling of nucleotides and their phosphate forms in the resurrection plant Haberlea rhodopensis Friv. The proposed ion-pair free method, exploiting a gradient of both organic com-ponent and buffer salt concentrations, was applied on tissue samples from leaves and roots of H. rhodopensis exposed to dehydration and subsequent rehydration. In the proposed method, 20 analyses (nucleosides and nucleotides) were separated by HILIC. This preliminary study identified remarkable features in nucleotide phosphate content and dynamics during desiccation and sub-sequent rehydration suggesting alternative energy metabolism pathways in drought tolerance of resurrection plants.