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Study of Chemical Constituents of Taxons from Order Laurales and Ranunculales with Potential Neuroprotective Activity
Hošťálková, Anna ; Opletal, Lubomír (advisor) ; Kokoška, Ladislav (referee) ; Drašar, Pavel (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Mgr. Anna Hošťálková Supervisor: Prof. RNDr. Lubomír Opletal, CSc. Title of Doctoral Thesis: Study of chemical constituents of taxons from order Laurales and Ranunculales with potential neuroprotective activity. Key words: Berberis vulgaris, Peumus boldus, Hydrastis canadensis, isoquinoline alkaloids, acetylcholinesterase, butyrylcholinesterase, prolyl oligopeptidase. Commercial goldenseal extrakt, boldo leaves and barberry root bark were selected as sources of isoquinoline alkaloids for study of their biological activity. Mixtures of summary tertiary alkaloids were prepared by standard extraction and subsequently fractionated in aluminium oxide chromatography column using the step gradient elution with petrol, chloroform and ethanol. Repeated column chromatographies, preparative TLC and crystallizations led to the isolation of 28 isoquinoline alkaloids, 6 of them were identificated as new structures (some of them were propably artifacts). The chemical structures of isolated compounds were determined on the basis of spectrometric techniques (NMR, MS) and by comparison with literature. Isolated alkaloids in sufficient amount were tested on ability to inhibit human...
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Alkaloids from Selected Species of Amaryllidaceaefamily, their Toxicity and Biological Activity (in vitro study) I.
Krejčí, Andrea ; Cahlíková, Lucie (advisor) ; Grančai, Daniel (referee) ; Kokoška, Ladislav (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate Mgr. Andrea Krejčí, née Kulhánková Supervisor Ing. Lucie Cahlíková, Ph.D. Title of Doctoral Thesis Alkaloids from selected species of Amaryllidaceae family, their toxicity and biological activity (in vitro study) I. Zephyranthes robusta and Chlidanthus fragrans bulbs were chosen for phytochemical study as biologically active Amaryllidaceae alkaloids source, based on bio-guided study using spectrophotometric Ellman's method and GC-MS analysis of alkaloid extracts. Bulbs were extracted with ethanol and the summary extract was fractionated by column chromatography with the use of Al2O3 as a stationary phase and gradient elution chloroform - ethanol. Column chromatography, preparative TLC and crystallisation led to isolation of pure compounds the chemical structure of which was elucidated by MS and D1- and D2-NMR analyses. From fresh bulbs of Chlidanthus fragrans 11 alkaloids were isolated of which deoxypretazzetine, belladine, 3-epimakronine, ismine, undulatine, buphanisine and ambelline were reported for the first time from the genus Chlidanthus. Compounds were evaluated for their human AChE, BuChE and POP inhibitory activity. From Zephyranthes robusta bulbs 14 alkaloids of...
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Biological Activity of Selected Taxons of Mushrooms from Divisions Ascomycota and Basidiomycota
Macáková, Kateřina ; Opletal, Lubomír (advisor) ; Kokoška, Ladislav (referee) ; Blunden, Gerald (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate Ing. Kateřina Macáková Supervisor Doc. RNDr. Lubomír Opletal, CSc. Title of Doctoral Thesis Biological activity of selected taxons of mushrooms from divisions Ascomycota and Basidiomycota. Though they are relatively insufficiently explored, mushroom are considered to be important source of bioactive substances, which is evident especially in Asian countries where some species of mushrooms, eventually their extracts or substances isolated from them, are used for healing of some diseases. This study, which covers 357 tested species of mushrooms growing in Czech Republic, focuses especially on antioxidant activity of mushroom extracts (2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and hydroxyl radical scavenging activity). Inhibitory activity towards human acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was also observed. For determination of antiradical activity, DPPH radical scavenging assay with the use of sequential injection analysis and chemiluminescence method for hydroxyl radical scavenging with the use of luminol were utilized. Total amount of phenolic substances was determined in the most active species. The correlation analysis showed that...
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Aspects of the use of herbal preparations adult population in the Czech Republic
Knotek, Karel ; Kokoška, Ladislav (advisor) ; Zelený, Václav (referee) ; Jahodář, Luděk (referee)
The subject of this thesis is to map the approach and behaviour of the adult population in the Czech Republic as regards the use of plant products (PP), both medicinal plants and herbal dietary supplements. For the public, the high prevalence of PP is a good opportunity to use such plants for self-medication or to prevent illness. The general part of this thesis describes the characteristics and importance of both groups of plant products, as well as the topical issue of the choice, use and role of these plants in the world and in the Czech Republic on the basis of research. The practical part then presents the results of a questionnaire survey of people who use plant products - customers of pharmacies in selected regions of the Czech Republic: the capital, Prague, the Region of North Bohemia, and the Region of South Bohemia. Based on classification attributes the work monitors the public's approach and behaviour as regards the choice and means of acquiring and using PP and activity in relation to self-medication, such as consulting the suitable selection of PP or people informing their doctor that they are using PP. The work ascertains to what extent users know about and are aware of medicinal plants, how they are collected and used, and their properties on which the respondents base their choice...
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Antimicrobial activity of extract from GRAS plant species agains oral pathogenic microorganisms
Pilná, Jindřiška ; Kokoška, Ladislav (advisor) ; Jaroslav, Jaroslav (referee)
Microbial oral diseases such as caries and periodontitis are among the most frequent human infections. Conventional chemical antiseptics used for their treatment and prevention often produce adverse side-effects, which restrict their long-term use. Although plants are considered as perspective sources of novel antimicrobial compounds, little is still known about their inhibitory properties against oral pathogens and about their safety while used on a daily basis. The objective of this study was to investigate in vitro growth-inhibitory effects of ethanol Generally Recognised as Safe (GRAS) plant and supercritical CO2 hop extracts on planktonic cultures of cariogenic, periodontal and candidal human pathogens, namely Aggregatibacter actinomycetemcomitans, Bifidobacterium dentium, B. longum, Candida albicans, Eikenella corrodens, Fusobacterium nucleatum subsp. vincentii, Lactobacillus salivarius subsp. salivarius, Porphyromonas gingivalis, Streptococcus mutans, S. salivarius subsp. salivarius and S. sobrinus using the broth microdilution method. The findings showed that ethanol extracts of all 109 GRAS plant species inhibited the growth of at least one microorganism under study with minimum inhibitory concentration (MIC) equal or lower than 4096 ug/mL. However, only six of them possessed very interesting antiseptic potential against the oral pathogens with MIC < 100 ug/mL. Additionally, three GRAS plant species showed good inhibitory activity with MIC = 128 ug/mL. As far as the particular results are concerned, the best antiseptic effect was observed for both Humulus lupulus CO2 supercritical and ethanol extracts that inhibited the growth of all microorganisms at MICs higher or equal to 8 ug/mL and MICs higher or equal to 16 ug/mL, respectively. Hence, the CO2 supercritical extraction proved to be superior for extraction of active constituents of H. lupulus. Further, the ethanol extracts of Capsicum annuum and C. frutescens showed significant antiseptic potential against S. sobrinus and S. salivarius (MICs from 64 to 128 ug/mL). The oral streptococci were also inhibited by Zanthoxylum clava-herculis (MIC higher or equal to 64 ug/mL), Helichrysum angustifolium and Myristica fragrans (MIC higher or equal to 128 ug/mL) which further showed the antimicrobial activity against F. nucleatum (MIC = 64 ug/mL). Interesting inhibitory effects exhibited an extract of Punica granatum against C. albicans (MIC = 128 ug/mL) and F. nucleatum (MIC = 64 ug/mL). Moreover, the growth of F. nucleatum was inhibited by extracts of Pimenta officinalis and Thea sinensis (MIC = 128 ug/mL). The chemical analysis of the CO2 supercritical H. lupulus extracts revealed that alpha and beta bitter acids represented the two major groups of constituents. Cohumulone was the predominant compound of the alpha acids, whereas colupulone was the prevalent constituent of the beta acids. Our results suggest that the six GRAS plant species, namely C. annuum, C. frutescens, H. lupulus, M. fragrans, P. granatum and Z. clava-herculis have good potential to become new safe antiseptic agents that might be used for incorporation into oral care products such as toothpastes and mouthrinses.
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Plant-derived products as effective inhibitors of diarrhea causing microorganisms
Šmíd, František ; Kokoška, Ladislav (advisor)
Since certain species are used in form of dietary supplements in developed world as antidiarrheal agents and because of presence of reports describing antidiarrheal properties of
medicinal plants used in traditional African medicine, we can expect, that systematic microbiological and phytochemical research of plant derived products (extracts, essential oils and their constituents) can lead to the discovery of effective antidiarrheal low-cost agents applicable for elimination of diarrhea in certain African regains.
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Assessment of in vitro antioxidant properties of medicinal and edible plant extracts
Tauchen, Jan ; Kokoška, Ladislav (advisor) ; Jaromír , Jaromír (referee)
Identification and characterization of plant-based products with antioxidant and anti-proliferative effects has received much interest over the past few years as possible therapeutic mean for treatment of diseases likely to be associated to oxidative stress (such as atherosclerosis, diabetes, and cancer). This study provides characterization of in vitro antioxidant and/or anti-proliferative potential and phytochemical profile of (i) 39 wine samples of underutilized Georgian grapevine cultivars, (ii) extracts of 22 samples of medicinal plants from Ethiopia and (iii) 23 samples of edible and medicinal plants from Peruvian Amazon. For this purpose, 2,2-diphenyl-1-picrylhydrazyl radical assay (DPPH), oxygen radical absorbance capacity (ORAC) assay, total phenolic content (TPC), and cell viability assay based on metabolization of tetrazolium bromide (MTT) to formazan, together with methods based on high performance liquid chromatography (HPLC-ultra violet/visible spectrometry and HPLC-tandem mass spectrometry) were used. Georgian red wines (particularly Saperavi cultivars) exhibited higher antioxidant capacity (average DPPH and ORAC values at 5.1 and = 10.6 g TE/L wine, respectively) in comparison to Central and West European cultivars [Pinot Noir (DPPH = 3.1 and ORAC = 9.4 g TE/L wine), Cabernet Sauvignon (DPPH = 3.0 and ORAC = 7.3 g TE/L wine) and Cabernet Moravia (DPPH = 2.0 and ORAC = 8.5 g TE/L wine)]. Georgian wines contained significantly greater concentrations of quercetin (between 14.44 and 1.07 ug/mL), kaempferol (between 1.68 and 0.03 ug/mL) and syringic acid (between 12.59 and 4.72 ug/mL), whereas possessed lower quantities of resveratrol (between 5.11 and 0.32 ug/mL) in comparison to Central and West European wines. Amongst edible and medicinal plants from Ethiopia and Peruvian Amazon, only Dodonaea angustifolia (IC50 for DPPH = 22.2 ug/mL, ORAC = 767.6 ug TE/mg extract; IC50 for Hep-G2 = 120.0 ug/mL), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract; IC50 for Hep-G2 = 50.5 ug/mL), Inga edulis (DPPH and ORAC = 337.0 and 795.7 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 36.3 and 57.9 ug/mL) and Oenocarpus bataua (DPPH and ORAC = 903.8 and 1024.4 ug TE/mg extract; IC50 for Hep-G2 and HT-29 = 102.6 and 38.8 ug/mL) have demonstrated combinatory antioxidant/anti-proliferative efficacy. Selective anti-proliferative activity was observed for Verbascum sinaiticum (IC50 for Hep-G2 = 80.6 ug/mL) and Annona montana (IC50 for Hep-G2 and HT-29 = 2.7 and 9.0 ug/mL, respectively). Above-mentioned plant material showed only weak or non-toxic effects towards normal cell line. Despite the fact that extracts of Jasminum abyssinicum (IC50 for DPPH = 26.3 ug/mL, ORAC = 1023.7 ug TE/mg extract), Rumex nepalensis (IC50 for DPPH = 5.7 ug/mL, ORAC = 1061.4 ug TE/mg extract), Mauritia flexuosa (DPPH and ORAC = 1062.9 and 645.9 ug TE/mg extract), Myrciaria dubia (DPPH and ORAC = 641.9 and 642.6 ug TE/mg extract) and Theobroma grandiflorum (DPPH and ORAC = 714.8 and 821.9 ug TE/mg extract) have exhibited considerable antioxidant effect, these species were found to possess moderate to low anti-proliferative potential or have shown to be toxic to normal cells line. In all cases it was detected that phenolic compounds content correlated strongly with antioxidant activity, however weakly with anti-proliferative effect. Results suggest above-mentioned species as prospective materials for further development of novel plant-based agents effective against oxidative stress related diseases. However, it is necessary to perform further research which would be focused on detailed characterization of their chemical composition, pharmacological effects and toxicological safety, in order to verify their possible practical use.
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In vitro antioxidative effect of medicinal plants from Ghana
Addai, Benjamin Berkoh ; Kokoška, Ladislav (advisor) ; Tauchen, Jan (referee)
The in vitro antioxidative activity of crude extracts derived from sixteen Ghanaian plant species (Allophylus spicatus, Cnestis ferruginea, Ficus thonningii, Indigofera hirsuta, Indigofera pulchra, Launaea taraxacifolia, Leea guineense, Mikaniopsis tedliei, Millettia thonningii, Philenoptera cyanescens, Salacia senegalensis, Senna occidentalis, Stachytarpheta indica, Tiliacora warneckei, Triumfetta rhomboidea, Vernonia colorata) were tested in frame of this study using 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity assay. The extract from the bark of Indigofera hirsuta has been found as the most active sample (IC50 = 12.84 more or less 0.82 microgram per millitres), because its activity is very close to the positive control Trolox and ascorbic acid. We expect that this finding may be used by pharmaceutical industry for development of new herbal-based nutraceuticals and pharmaceutical preparations.
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In vitro determination of antimicrobial, antioxidative and antiphlogistic aktivity of quinones from seeds of Nigella sativa
Kokoška, L. ; Maršík, Petr ; Landa, Přemysl ; Tesařová, H. ; Svobodová, B. ; Halamová, K. ; Flesar, J. ; Přibylová, Marie
The in vitro anti-yeast, antioxidant, and anti-inf1ammatory activities ofblack cumin (Nigella sativa) seed quinones, namely dithymoquinone (DTQ), thymohydroquinone (THQ), and thymoquinone (TQ), were evaluated in frame of this work. The results showed that THQ and TQ possessed significant anti-yeast activity and affected the growth of aH strains tested at two pH levels with minimum inhibitory concentrations ranging from 8 to 128 !lg/ml. The best scavenging activity was produced by THQ, which showed a remarkable activity of 2.60 Trolox equivalents (TE) in a concentration range between 1.6 and 6.4 !lg/mL and lCso value of 2.4 !lg/mL in ORAC and DPPH assays, respectively. Contrastingly, TQ possessed only weak DPPH scavenging efficacy (ICso = 170 !lg/mL) but significant antioxidative action of 1.91 TE in ORAC assay. In anti-inf1ammatory assay, THQ and TQ possessed significant inhibitory activity against COX-l and -2 at the concentrations comparable with indomethacin. The data presented in this work suggest that THQ and TQ are biologically effective agents with potential for application in food or phalmaceutical industries.
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