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Bacterial interactions and secondary metabolites in plant and soil environment
Rapoport, Daria ; Marečková, Markéta (advisor) ; Lovecká, Petra (referee) ; Brabcová, Vendula (referee)
Phylum Actinobacteriota represents one of the major phyla in plant and soil environments. Known for the ability to produce numerous secondary metabolites, Actinobacteriota may affect other bacteria and plants in various ways. The thesis aimed at assessing the connection between the production of secondary metabolites and interactions of actinobacteria in plant and soil environments. In the first part, we assessed how rare actinobacteria from acid soil affect cultivable soil bacteria. We isolated a collection of actinobacteria from acid soil dominated by previously uncultivable lineage and isolated a representative described as a new family Treboniaceae and multiple other potentially novel species of known genera. The genome and metabolome analysis of Trebonia kvetii, sp.nov. gen.nov., demonstrated its ability to produce unusual and potentially novel bioactive metabolites. We designed an experiment where a single strain was co-cultivated with the total soil bacterial community of the same soil in a set up, where a free exchange of diffusible metabolites was allowed between them. Three actinobacteria strains coming from distinct lineages were selected for this interaction. Each strain significantly and specifically affected cultivable bacteria as well as the metabolite pool, part of which was induced...
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Secondary metabolites in fungal pathogenesis
Veselý, Martin ; Čmoková, Adéla (advisor) ; Machová, Lenka (referee)
The ability of fungal pathogens to induce infection and later survive in its host is dependent on virulence factors. Often these factors are based on primary metabolites (hydrophobins, proteases, phospholipases, catalases etc.). Nonetheless many pathogen produced secondary metabolites are also involved in the infection process. Their true role during infection used to be rather undervalued. First part of this bachelor degree thesis aims to describe host-pathogen relation and afterwards introduce reader with some basic, commonly accepted virulence factors of fungi. In the second part of this thesis known roles of secondary metabolites are described in each stages of progressing infection. In the first stage a pathogen needs to create a suitable habitat on host tissues to ensure growth. This is in part done by antimicrobial substances (...). In later stages pathogen prevents phagocytosis of its spores by host (melanins). Successful infection is often accompanied with host tissue damage that is induced by production of cytotoxic substances (xanthomegnin, riboflavin) and immunoregulation of host immune system (gliotoxin, pseurotin). Last but not least there are virulence factors that ensure prolonged survival in host (siderophores). Fungal pathogens of poikiloterm animals are mostly not primary...
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Natural compounds potentially influencing neurodegenerative diseases
Mňuková, Daniela ; Opletal, Lubomír (advisor) ; Suchánková, Daniela (referee)
Mňuková D.: Natural compounds potentially influencing neurodegenerative diseases. Diploma thesis, Charles University in Prag, Faculty of Pharmacy in Hradec Králové, Department os Pharmacognosy and Pharmaceutical botany, Hradec Králové 2022, 88 s. This research diploma thesis draws mainly from foreign professional literature. It provides an overview of important natural substances that potentially influence neurodegenerative diseases. The first part describes the moct common neurodegenerative diseases, their characteristics, epidemiology, pathogenesis and clinical picture. These diseases include Alzheimer's disease, Parkinson's disease, Lewy body dementia, multisystem atrophy, Pick's disease and other tauopathies, Huntington's disease, spinocerebellar ataxia and amyotrophic latelar sclerosis. The second part of diploma thesis presents natural substances that have been studied in preclinical and clinical studies in the last two decades for their potential to positively affect neurodegenerative diseases. The last part discusses the contribution of these natural substances fot therapy and prevention of neurodegenerative diseases. Keywords: neurodegenerative diseases, natural compounds, Alzheimer's disease, bioactive compounds
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Secondary metabolites of familly Apocynaceae as a souce of cytotoxic substances
Měšťanová, Kristýna ; Šafratová, Marcela (advisor) ; Hradiská Breiterová, Kateřina (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy and Pharmaceutical Botany Student: Kristýna Měšťanová Thesis supervisor: PharmDr. Marcela Šafratová, Ph.D. Thesis title: Secondary metabolites of the Apocynaceae family as a source of cytotoxically active substances The diploma thesis is focused on elaborating a comprehensive overview of secondary metabolites of the Apocynaceae family with a focus on their application in practice and the importance of Vinca alkaloids in the treatment of Hodgkin's and non- Hodgkin's disease. First, the major representatives of the Apocynaceae family, their constituents and mechanisms of action are mentioned. The uses and the desired and side effects are described and the effects of cardenolides are also stated. The work also deals with Hodgkin's and non-Hodgkin's disease, their incidence, symptomatology and classification of these diseases. Risk factors, including biological and genetic characteristics, are listed. Furthermore, the topic of staging and the treatment of these diseases according to the individual stages of the disease and differences in therapy of specific groups of patients are elaborated. The individual types of lymphomas, their diagnosis and subsequent treatment, including side effects, are described in detail. The...
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Secondary metabolites and antimicrobial effects of neotropical members of the genus Hermatomyces
Ježková, Tereza ; Koukol, Ondřej (advisor) ; Žabka, Martin (referee)
Species of the genus Hermatomyces (Pleosporales) saprotrophs on wood and litter in the tropics. Since the secondary metabolites of this genus have not been investigated so far, this thesis focuses on them. In this thesis, the antifungal properties of the genus Hermatomyces were verified by pairing experiments on agar plates and by testing the minimum inhibitory concentrations of extracts obtained from fungal biomass. The extract of one selected strain, H. reticulatus CCF 5893, was separated by preparative HPLC. The selected biologically active fractions were purified and the chemical structure of the separated compounds was determined by nuclear magnetic resonance analysis and X-ray crystallography. Two compounds were found in this species: palmarumycins C2 and C12, which have antifungal properties. Furthermore, a total of 25 Hermatomyces strains were compared in terms of secondary metabolite production (by testing their minimum inhibitory concentrations and comparing HRMS data). Unique compounds were produced by H. megasporus, which also showed the highest antimicrobial activity of all species and is therefore the most suitable species for further study of antimicrobial compounds of this genus.
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Epiphytic species of Lecanora subfusca group in the Czech Republic
Malíček, Jiří ; Palice, Zdeněk (advisor) ; Vondrák, Jan (referee)
The main aim of this bachelor work is to summarize knowledges on species of the Lecanora subfusca group growing in the Czech Republic, eventually taxa their occurence may be expected in our area. Only epiphytic and/or epixylic species are included in this study because of a large diversity of the group. Ten taxa have been published from the country. This group is poorly explored in Central Europe because of difficult determination of single species. A comprehensive treatment is lacking in this area. For most taxa of this group only limited information on ecology, distribution, chemistry and taxonomic concepts exists. The present work is reviewing up-to-date knowledge of this group. Historical sources were based mainly on morphological and anatomical data. These were evaluated and excerpted. The bachelor work should serve as a basement for the following diploma thesis.
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Functions of secondary metabolites of lichens
Zvěřinová, Gabriela ; Svoboda, David (advisor) ; Bouda, František (referee)
This bachelor thesis is a review of available literature about lichen secondary metabolites and their functions. Lichens produce a great variety of these compounds; most of them are unique to the lichen symbiosis and are not found in higher plants. Besides the role of these compounds in chemotaxonomy and systematics, lichen secondary metabolites exhibit various biological functions and can affect biotic and abiotic interactions of lichens with their environment. Well-known and often described functions of lichen substances include especially antimicrobial, antiherbivory and antioxidant activity, allelopathy, metal homeostasis and photoprotection. This thesis is focused on these functions and summarizes current knowledge in this area. Key words: lichen, secondary metabolites, allelopathy, antimicrobial activity, herbivory, antioxidant activity, photoprotection, metal homeostasis, pollution tolerance, literary review
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Isolation of alkaloids of the species Magnolia soulangeana Soul.-Bod. and study of their biological activity
Baková, Izabela ; Hošťálková, Anna (advisor) ; Opletal, Lubomír (referee)
Baková I.: Isolation of alkaloids of the species Magnolia soulangeana Soul.-Bod. and study of their biological activity. Diploma thesis, Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové, 2017. Key words: Magnolia solulangeana, secondary metabolites, alkaloids, biological activity. Secondary metabolites of plants are responsible for various biological activities. Alkaloids were described as a potentially suitable for Alzheimer's disease therapy (AD) through their inhibition activities against cholinesterases. Nowadays, these substances are important medicine for AD, therefore a screening of herbal drugs is still a current topic. An alkaloid extract of Magnolia × soulangeana flowers was tested in a preliminary testing on anticholinesterase activity. Because of the promising results, it was chosen for an isolation and identification possible effective alkaloids. The extract was separated by a column chromatography using aluminium oxide and a step gradient elution. Alkaloids were isolated by a repeated preparative thin-layer chromatography. Individual alkaloids were identified by a structural analysis (NMR, MS) and then their optical activity was measured. Substances were tested for an inhibition activity against human...
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Study of secondary metabolites in explantat culture of Trifolium pratense L.
Jindřišková, Zuzana ; Kašparová, Marie (advisor) ; Siatka, Tomáš (referee)
Zuzana Jindřišková The Study of Secondary Metabolites in Explant Culture of Trifolium pratense L. The basic prerequisite for a successful elicitation that is used to increase the production of secondary metabolites is, among others, finding a suitable elicitor, its concentration and optimal duration of effect of the elicitor on the plant in vitro culture, which was the main subject of this diploma thesis. The focus of our observations was the influence of 6-, 24- , 48- and 168-hour effect of nickel chloride solution (in the concentrations of 0.1 mmol, 1 mmol, 10 mmol and 100 mmol) and zinc sulphate (in the concentrations of 0.1 µmol, 1 µmol, 10 µmol a 100 µmol) on the production of flavonoids and isoflavonoids in the suspension culture of Trifolium pratense L. variety Tempus. The culture was cultivated on the Gamborg nutrien medium with the addition of 2 mg.l-1 2,4- dichlorophenoxyacetic acid and 2 mg.l-1 6- benzylaminopurine at 25řC and the light period of 16 hours light/ 8 hours dark. The maximum content of flavonoids, which was found out by the photometric determination of the Czech Pharmacopoeia 2009, was proved in the suspension culture of Trifolium pratense L. variety Tempus (0.406%) after 48-hour elicitation of nickel chloride solution in the concentration of 0.1 mmol, when there was a...
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Possibilities of affecting secondary metabolites production in "in vitro" cultures of medicinal plants
Sojková, Kristýna ; Tůmová, Lenka (advisor) ; Martin, Jan (referee)
1 ABSTRACT Possibilities of affecting secondary metabolites production in in vitro cultures of medicinal plants Elicitation is one of the methods used for increasing the production of secondary metabolites.The aim of this work was to affect the flavonoid production in callus and suspension cultures of St. John's Wort (Hypericum perforatum L.). Abiotic elicitor selendioxide in various concentrations (9.012.10-3 mol/l; 9.012.10-4 mol/l; 9.012.10-5 mol/l) was added in in vitro culture. The content of flavonoids was determinated by high performance liquid chromatography (HPLC). The samples were taken after 6, 12, 24, 48, 72, 168 hours after elicitor treatment. Selendioxide raised the production of hyperoside and quercitrin. The highest content of hyperoside (0.2 %) was detected after selendioxide (in concentration of 9.012.10-3 mol/l) treatment and 168 hours sampling in suspension culture. The highest production of quercitrin (0.37 %) was reached after selendioxide treatment (in concentration of 9.012.10-3 mol/l) and 6 hours sampling also in suspension culture. Production of flavonoids in callus cultures wasn't so much affected in comparison with suspension cultures after elicitor treatment. Flavonoid releasing into nutrient medium was also studied. The highest content of hyperosid (1.02 mg/100ml) was found in...
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