Search

Background: Extracts obtained from different Betonica species have been shown to possess important biological properties. The present study aimed to investigate the cytotoxicity, antitumor and immunomodulatory potential of the endemic plant Betonica bulgarica (Lamiaceae) and thus, reveal new aspects of its biological activity. Methods: Methanolic extract obtained from inflorescences was analyzed for cytotoxicity against mammalian cell lines. The antitumor potential of the sample was determined using human cervical and lung adenocarcinoma cells (HeLa and A549). Programmed cell death-inducing effects against HeLa cells and peripheral blood lymphocytes, as well as immunomodulatory properties of the extract were determined by flow cytometry analysis. Results: The research results demonstrated that the extract has significant inhibitory potential against HeLa cells (mean IC50 value 119.2 μg/mL). The sample selectively induced apoptotic death in tumor cells. Cytotoxic effects towards mouse cell lines were detected following treatment with high concentrations of Betonica bulgarica extract (200 and 250 μg/mL). Twenty-four-hour ex vivo incubation of peripheral blood leucocytes in growth medium containing plant extract induced prominent effects in distinct immune cell populations. They included elevated levels of CD25+ and CD56+ T cells' lymphocytes, particularly CD4+CD25+ and CD8+CD56+ cells. Conclusions: The present study demonstrates that Betonica bulgarica inflorescence extract possesses potential beneficial antitumor and immunomodulatory activity and could serve as a source of bioactive compounds with biomedical application. [ABSTRACT FROM AUTHOR]

The present study presents data on the anatomical characteristics of the leaf and stem in Marrubium friwaldskyanum and Marrubium peregrinum. The leaves in both species are amphistomatic with diacytic and anomocytic stomata. The leaf lamina shows differentiation of palisade and spongy tissue, and collateral vascular bundles. Non-glandular and glandular trichomes have been found on the epidermis of the leaves and stem. The non-glandular trichomes are unicellular linear and multicellular branched. Glandular trichomes are peltate, with a single-celled or two-celled structure. There is a difference between the two species in terms of the width of the epidermal cells of the stem, the thickness of the cortex, the thickness of the xylem and the phloem in the stem. The established differences in the anatomical features can be useful in future taxonomic studies within the genus Marrubium. [ABSTRACT FROM AUTHOR]

Betonica bulgarica Degen et Neič. (syn. Stachys bulgarica Hayek) is a Bulgarian endemic plant included in Red Data Book of Bulgaria under the category "endangered". The aim of the present study is to provide data about the antimicrobial activity of B. bulgarica leaf, flower, seed, stem and root methanolic extracts against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Bacillus cereus, Aspergillus ochraceus 2002 IM-BAS, Fusarium moniliforme 394 FN-9, Fusarium graminearum 2294 IMI 155426 and Penicillium verrucosum 2003 NRRL F-143. Antimicrobial activity of the extracts was evaluated by agar well diffusion method. Root extracts of B. bulgarica exhibited the highest antibacterial activity against S. aureus and B. cereus with large zones of inhibition. All extracts demonstrated either low and statistically insignificant activity against E. coli or a lack thereof. As a whole, extracts of Ablanovo area (in Sinite kamani National Park) exerted the highest activity against S. aureus, B. cereus and E. coli. Leaf, flower, stem and root extracts of B. bulgarica showed either a lack of antifungal activity or low and statistically insignificant one. [ABSTRACT FROM AUTHOR]

The present work presents a comparative anatomical study of the leaf epidermis of the Bulgarian endemic Micromeria frivaldszkyana (Degen) Velen. and Clinopodium vulgare L., belonging to the family Lamiaceae. In both species they occur diacytic and anomocytic stomatal type, while the indumentum is presented by multicellular, linear covering trichomes and multicellular, stacked glandular trichomes. The results obtained from the statistical data processing contribute to the distinction between the two species with respect to the peculiarities of the leaf epidermis. Taxonomically significant anatomical features for their determination are: number, width and length of stomata on the abaxial epidermis; width of on the adaxial epidermis; number, width and length of basic epidermal cells along both epidermis and thickness of upper and lower cuticle. [ABSTRACT FROM AUTHOR]

The current study investigates the content of sugars, organic acids, phenolic acids and flavonoids, as well as antioxidant and antimicrobial activity of Balkan-endemic Micromeria frivaldszkyana. Glucose was the most abundant sugar in the plant (2.77%), followed by fructose (1.18%) and galactose (0.82%). Eight organic acids were detected with quinic acid being in the highest content—556.3 mg/100 g DW. From the individual phenolic acids, rosmarinic acid was found in the most significant amounts (2040.1 ± 1.97 mg/100 g) and hesperidin was the major representative of flavonoids with content 131.2 ± 5.6 mg/100 g DW. The antioxidant activity of the plant was studied by six methods: 2,2′-diphenylpicrylhydrazyl (DPPH)—286.4 ± 10.43 mM TE/g, 2,2′azinobis (3)-ethylbenzthiazoline-6-sulfonic acid (ABTS)—358.4 ± 10.4 mM TE/g, ferric reducing antioxidant power (FRAP)—388.0 ± 32.4 mM TE/g, cupric reducing antioxidant capacity (CUPRAC)—905.6 ± 19.2 mM TE/g, Oxygen Radical Absorbance Capacity (ORAC)—3250.5 ± 208.1 µmol TE/g and Hydroxyl Radical Averting Capacity (HORAC)—306.1 ± 23.5 µmol GAE/g. In vitro antimicrobial activity against nine microorganism was evaluated but the extract displayed antimicrobial activity only against Listeria monocytogenes ATCC 19111 with inhibition zone diameter 9 mm and minimal inhibitory concentration (MIC) 10 mg/mL. [ABSTRACT FROM AUTHOR]