Emil Švajdlenka

Comparison of Essential Oils from Marrubium vulgare L. and M. peregrinum L.

Abstract The chemical composition of the essential oils obtained from the flowering aerial parts of Marrubium vulgare L.. and Marrubium peregrinum L. were determined by GC/MS. Twelve components were identified in M. vulgare oil with β-caryophyllene (45.8%) and germacrene D (14.4%) being the major constituents. In M. peregrinum oil, sixteen compounds were identified with β-caryophyllene (31.3%), germacrene D (28.1%) and bicyclogermacrene (15.3%) predominating.

Composition of the Oil from the Flowerheads of Anthemis tinctoria L. Cultivated in Slovak Republic

Abstract The chemical composition of the essential oil obtained from the flowerheads of Anthemis tinctoria L(Asteraceae) was analyzed by capillary GC/MS. 86 components of the oil were separated, 48 of which were identified. The major constituents were 1,8-cineole (7.9%), β-pinene (7,3%), decanoic acid (5.4%) and α-pinene (4.4%).

Spherical dodecyltrimethylammonium bromide micelles in the limit region of transition to rod-like micelles. A light scattering study

Abstract Dynamic and static light scattering measurements were performed on dodecyltrimethylammonium bromide aqueous solutions in the presence of sodium bromide at different concentrations. The power law dependence was applied to the diffusion coefficient D vs. c b ( c , surfactant concentration) and the decrease of the parameter b with increasing salt concentration was observed. The dependencies of D and b on the salt concentration are decreasing and show a plateau at intermediate salt concentrations. The Debye plot from the static light scattering measurements shows the presence of stable spherical micelles in the solution at low salt concentration with molecular weight about 23 000 and aggregation number 65–80. The logarithmic plot of the molecular weight vs. the ionic strength shows two linear regions with an intercept at the salt concentration 1.9 M. However, the values of the molecular weight and the aggregation number are too small to allow the assumption of a rod structure.

Composition of the essential oil from Melissa officinalis L. cultivated in Slovak Republic

Abstract The leaf oil obtained by hydrodistillation from Melissa officinalis L. c. v. citra cultivated at Nitra locality (Slovak Republic) was analyzed by GC and GC/MS. M. officinalis oil was found to contain geranial (33.60%), neral (22.18%), citronellal (11.30%), caryophyllene oxide (8.35%), geranyl acetate (5.89%), and β-caryophyllene (4.20%) as the major components. More than 50 components were identified in the oil.

Comparison of perturbation effect of propranolol, verapamil, chlorpromazine and carbisocaine on lecithin liposomes and brain total lipid liposomes. an EPR spectroscopy study

Effect of verapamil, propranolol, chlorpromazine and carbisocaine on dynamics and/or order of liposomes (perturbation effect), prepared from different molar ratios of lecithin (PC) and rat brain total lipids (TL) was studied by EPR spectroscopy using spin probes 16-doxyl stearic acid and 14-doxyl phosphatidylcholine. The PC liposomes had higher dynamics and/or lower order than the TL liposomes. The perturbation effect of the drugs depended largely on the lipid composition of the liposomes. The drugs at the drug/lipid molar ratios from 0.1 to 1 increased membrane dynamics and/or decreased membrane order. The drugs had the most pronounced perturbation effect in the liposomes prepared from brain total lipids. The effect of the drugs decreased with decreasing the TL/PC ratio in the liposomes and was lowest, almost diminished, in the PC liposomes. Increasing concentration of the drugs decreased the difference between the dynamics and/or order of the PC and TL liposomes and so eliminated the influence of lipid composition on these membrane parameters. The results emphasize the role of lipid composition in studies concerning drug-lipid interactions in model and biological membranes.

Determination of uracil herbicide residues and components in essential oil of Melissa officinalis L. in its main development phases

Abstract Uracil herbicide residues were studied in the medicinal plant lemon balm (Melissa officinalis L. c.v. citra) grown under standard agrochemical conditions. The residues from the uracil herbicides bromacil, lenacil, and terbacil were determined at selected phases of flower development. In addition the main components of the M. officinalis oil were determined by GC/MS at the same stages of development such as bud set, at the beginning of bloom, and at full bloom. TLC on silica gel with selective biochemical detection was used for the determination of herbicide residues in the plant material. It was found that the sample of plant material harvested in full bloom state contained 0.007 mg/kg of bromacil residue, and 0.005 mg/kg of lenacil and terbacil residues. The application of the herbicide at a rate of 2 kg/ha did not affect the quality of the treated plant.

Differences in essential oil production and leaf structure in pheno-types of damiana(turnera diffusa willd.

Plants of damiana(Turnera diffusa Willd.) are important to industry and traditional medicine in semi-arid climates. Although all populations are wild, no reports have been made previously of their different phenotypes. Here, we investigated various micromorphological characteristics and the levels of essential oils in two phenotypes. Oils were extracted from fresh leaves via hydrodistillation and analyzed by gas chromatography-mass spectrometry. Morphological analyses were conducted under a stereoscopic microscope and with a scanning electron microscope. In all, 56 compounds were identified, enabling us to distinguish separate phenotypes. DL1 plants mainly contained 1,8-cineole, 10-epi y eudesmol, and guaiol; whereas those of DL2 primarily constituted ß-pinene, ß-caryophyllene oxide, cadinene, and α-cadinol. These two phenotypes also differed in their morphologies, with DL1 leaves showing elevated essential oil concentrations, but lacking trichomes. In contrast, the DL2 plants had lower contents of essential oils but did possess trichomes on their abaxial and adaxial leaf surfaces. This documentation of individual damiana phenotypes is the initial process toward validating the quality of essential oils from this species as well as inherent structural variations.

Plantago lanceolata L. water extract induces transition of fibroblasts into myofibroblasts and increases tensile strength of healing skin wounds.

Although the exact underlying mechanisms are still unknown, Plantago lanceolata L. (PL) water extracts are frequently used to stimulate wound healing and to drain abscesses. Therefore, in this experimental study the effect of PL water extract on skin wound healing was studied in Sprague‐Dawley rats.

Inhibition of lipid peroxidation of lecithin liposomes kept in a pH-stat system near neutral pH

During 5 days of autoxidation of egg lecithin liposomes in nonbuffered saline pH dropped from an initial value of 7.4 to 4.5. A linear relationship between oxidation index and pH was obtained. Lipid peroxidation, monitored as conjugated diene and TBA-reactive products, was inhibited significantly by keeping the samples under pH-controlled conditions (7.4 +/- 0.5), compared to controls. Obtained results indicate that the buffering capacity of Tris and Hepes buffers may play a role in their recently reported (D. Fiorentini et al. (1989) Free Radical Res. Commun., 6, 243) inhibitory action against lipid peroxidation of lecithin liposomes.

Hibiscus sabdariffa L. and Its Bioactive Constituents Exhibit Antiviral Activity against HSV-2 and Anti-enzymatic Properties against Urease by an ESI-MS Based Assay

For decades, Hibiscus sabdariffa L. and its phytochemicals have been shown to possess a wide range of pharmacologic properties. In this study, aqueous extract of Hibiscus sabdariffa (AEHS) and its bioactive constituent protocatechuic acid (PCA), have been evaluated in vitro for their antiviral activity against HSV-2 clinical isolates and anti-enzymatic activity against urease. Antiherpetic activity was evaluated by the titer reduction assay in infected Vero cells, and cytotoxicity was evaluated by the neutral red dye-uptake method. Anti-urease activity was determined by a developed Electrospray Ionization-Mass Spectrometry (ESI-MS)-based assay. PCA showed potent anti-HSV-2 activity compared with that of acyclovir, with EC50 values of 0.92 and 1.43 µg∙mL−1, respectively, and selectivity indices > 217 and > 140, respectively. For the first time, AEHS was shown to exert anti-urease inhibition activity, with an IC50 value of 82.4 µg∙mL−1. This, combined with its safety, could facilitate its use in practical applications as a natural urease inhibitor. Our results present Hibiscus sabdariffa L. and its bioactive compound PCA as potential therapeutic agents in the treatment of HSV-2 infection and the treatment of diseases caused by urease-producing bacteria.