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Studies concerned the effect of different fractions obtained from white scales of Hippestrum after drying and from scales after red colouration as a result of wounding of fresh white scales, on the growth and development of formae speciales of Fusarium oxysporum, non-pathogenic fungi for Hippeastrum. Fraction B, at the concentration of 250 and 500 μg・cm⁻³ obtained from red wounded scales of Hippeastmm and containing two red compounds (Hpp-1 and Hpp-2) showed a strong inhibitory effect on the linear growth of mycelium, germination of spores and germ tube growth of Fusarium oxysporum Schlecht, isolated from Fritillaria, F. oxysporum f. sp. callistephi and F. oxysporum f. sp. tulipae. Fractions A, C and D from red wounded scales at the same concentrations did not inhibit or had a slight antifungal activity on mycelium growth of tested pathogens in vitro. Fractions A, B and D obtained in the same way from white scales of Hip- peastrum did not inhibit mycelial growth of F. oxysporiim SCHLECHT, from Fritillaria and F. oxysporum f. sp. tulipae. Fraction C at a concentration of 500 μg・cm⁻³ showed a slight inhibition of the F. oxysporiim from Fritillaria. All fractions (A, B, C and D) at a concentration of 500 μg・cm⁻³ obtained from white scales of Hippeastrum showed a slight inhibition of the F. oxysporum f. sp. callistephi in vitro. Subfractions B₂ and B₃, free from red compounds, and subfraction B₅ (containing mostly red compound Hpp-1), greatly limited the growth of tested pathogens in comparison to the control. Subfraction B₈, containing mostly red compound Hpp-2 and a small amount of red compound Hpp-1, applied at the same concentration did not inhibit or had little antifungal activity against tested formae speciales of F. oxysporum.
Chloroform, butanolic and water fractions from the methanolic extracts of Lamium album L. and L. purpureum L. flowers and different organs of mistletoe (Viscum album L.), namely leaves, stalks and fruits were investigated for the free radical scavenging properties by using colour free radical DPPH • as a stain reagent for dot-blot assay on a T LC plate and two-dimensional thin-layer chromatography (2D-TLC) analysis (2D-TLC-DPPH test) as well as a dye reagent for the spectrophotometric assay. For each plant material, butanolic fractions showed the strongest activity, of which those of the Lamium species were nearly equal to that of the known antioxidant - BHA. According to 2D-TLC chromatography, the phenolic compounds present were responsible for the antiradical activity of the fractions.
Eryngium planum L. cell and organ cultures were maintained on Murashige and Skoog media (MS), supplemented with exogenous hormones of different types and various concentrations for high biomass growth. The callus and cell suspension cultures were treated with increased sucrose concentration and/or elicited by methyl jasmonate for the enhancement of selected phenolic acids accumulation. Three phenolic acids, rosmarinic acid (RA), chlorogenic acid (CGA) and caffeic acid (CA), were detected by HPLC-DAD in those cultures. The sum of their content in the dry material was found to be higher in the shoot culture (3.95 mg g⁻¹), root culture (7.05 mg g⁻¹), callus (6.20 mg g⁻¹) and cell suspension (2.04 mg g⁻¹) than in the leaves (1.87 mg g⁻¹) and roots (0.76 mg g⁻¹) of intact plants. The major compound of in vitro cultures was always rosmarinic acid. The content of RA could be increased approximately threefold (16.24 mg g⁻¹) in the callus culture and approximately twofold (3.91 mg g⁻¹) in the cell suspension culture by elicitation with 100 µM methyl jasmonate (MeJA). The higher concentration of sucrose (S) in the medium (5, 6 %) led to over a twofold increase of CGA content in the callus culture (2.54 mg g⁻¹). The three mentioned phenolic acids have been found in E. planum undifferentiated and differentiated in vitro cultures for the first time.
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The antimicrobial activity of ethanolic extracts from leaves and roots of three Eryngium L. genera (E. planum, E. campestre, E. maritimum) native to Poland was tested by the method of series dilutions against different Gram-positive bacteria (two strains) and fungi (five species). The extracts were analyzed by TLC method to confirm phenolic acids, triterpenoid saponins, flavonoids and acetylenes presence. The antimicrobial activity of extracts compared with the reference substance were expressed by Minimal Inhibitory Concentration (MI C). The results have shown that the ethanolic extracts inhibit the growth of Staphylococcus aureus and all tested fungi.
From plantlets of Byblis liniflora Salisb. (Byblidaceae), propagated by in vitro culture, four phenylethanoid glycosides - acteoside, isoacteoside, desrhamnosylacteoside and desrhamnosylisoacteoside were isolated. The presence of acteoside substantially supports a placement of the family Byblidaceae in order Scrophulariales and subclass Asteridae. Moreover, the genera containing acteoside are listed; almost all of them appear to belong to the order Scrophulariales.
Two natural flavonoids, quercetin and isorhamnetin 3-O-acylglucosides, were examined for their inhibitory influence on the in vitro production and release of reactive oxygen spe­cies in polymorphonuclear neutrophils (PMNs). The generation of superoxide radical, hy­drogen peroxide and hypochlorous acid were measured by, respectively, cytochrome c re­duction, dichlorofluorescin oxidation and taurine chlorination. Membrane lipid oxidation was studied by the thiobarbituric acid method in mouse spleen microsomes. The addition of flavonoids at the concentration range 1-100 uM inhibited PMNs oxidative metabolism and lipid peroxidation in a dose-dependent manner. The results suggest that these flavonoids suppress the oxidative burst of PMNs and protect membranes against lipid peroxidation.
A short review on phytochemical analysis of in vitro cultures of selected Polish rare and endangered plants is presented. Analysed secondary metabolites, present in investigated species, are responsible for raw materials medical activity. Phenolic compounds (flavonoids and phenolic acids), secoiridoids, saponins and fatty acids were investigated in micropropagated plants, shoot cultures or callus tissue of eleven plant species from the genera: Gentiana L., Oenothera L., Rubus L., Solidago L., Pinguicula L., Primula L., Eryngium L. The studied species represented medicinal plants or plants used in folk medicine in which the secondary metabolites are usually responsible for their therapeutic properties. The investigations showed that those plants contain pharmaceutically promising compounds. Therefore, plant biotechnology can be used for rapid propagation of rare or endangered plants and the regenerated plants may be used as a source of those rare medicinal plants.
Introduction: Due to increasing resistance against antibiotics and antifungal agents, crude plant extracts, fractions, and isolated pure compounds became a new interest as antimicrobial agents. Objectives: The antimicrobial activity of methanolic extracts and fractions of Eryngium planum L., E. campestre L., and E. maritimum L. was evaluated against selected bacteria, yeast and mould, and compared in tested Eryngium species and in their organs. Methods: The antimicrobial activity was studied with use of broth microdilution method. The antibacterial (Staphylococcus aureus, Pseudomonas aeruginosa) and antifungal (Candida albicans, Aspergillus niger) activity of selected extracts and fractions compared with the reference substance was expressed by Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal/Fungicidal Concentration (MBC/MFC).The extract and fraction compounds were identified on the basis of TLC examination. Results: The saponin-phenolic acid fractions of E. maritimum and E. planum and a saponin fraction of E. planum showed the highest activity against S. aureus (MIC = 1–2.5 mg·ml-1). The growth of C. albicans was inhibited by methanolic extract of E. planum cell suspension culture (MIC = 7.8 mg·ml-1). Conclusion: The antimicrobial activity depends on the Eryngium species, tested biomass, and microorganism.
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