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Secondary Metabolits of Bryophytes
Štěpán, Michal ; Soldán, Zdeněk (advisor) ; Skýbová, Jana (referee)
The bryophytes are a very old group of plants that are credited with being the first to make the transition to land. To make this land transition possible, plants needed to develop strategies to combat various external environmental factors. And these means, to effectively combat the struggle on land, are various secondary metabolites. It goes without saying that the development of various protective mechanisms did not end there. In the conditions in which mosses live, they need to fight against various fungi and bacteria. In the fight against these organisms, they also use various secondary metabolites, of course. Moss secondary metabolites are a very interesting and understudied field. In this work, information regarding secondary metabolites of bryophytes and their analysis as well as the possible uses of isolated secondary metabolites are included. The beginnings of secondary metabolite research are covered, from one of the first terpenes isolated, which was marchantin in Marchantia polymorpha, to present-day studies focusing on the discovery of new secondary metabolites directly in selected representatives of bryophytes and, of course, their applicability in human activities. It has been confirmed from various international publications that bryophytes produce specific secondary metabolites...
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Terpene discovery combining in silico and molecular biology approaches
Smrčková, Helena ; Pluskal, Tomáš (advisor) ; Hodek, Petr (referee)
Terpenoids are the largest class of natural products with remarkable chemical and structural diversity, making them a significant source of compounds for drug discovery. Terpenoids are used as food flavours, therapeutics, cosmetics, hormones or fuel. The starting scaffolds for terpenoid biosynthesis are condensed and, in some cases, cyclic carbohydrates synthesized from linear isoprenyl pyrophosphate precursors by terpene synthases. The enzyme family of terpene synthases is extensive and possesses well-characterized motifs and function-determining domains that can be used to search for homologous proteins with unknown catalytical function that might produce new compounds. Thanks to a bioinformatic pipeline developed in the Pluskal Lab in the Institute of Organic Chemistry and Biochemistry CAS, candidate terpene synthases with the potential to produce new terpene scaffolds were mined in silico from large protein sequence repositories. I expressed nine selected proteins originating from plants, bacteria, and fungi in the engineered budding yeast strains JWY501 and ZX178-08 that overproduce isoprenyl pyrophosphates. I then analysed the resulting yeast cell culture extracts using gas chromatography- and liquid chromatography-mass spectrometry. Five out of nine proteins exhibited terpene synthase...
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Antiproliferative, antioxidant and anti-inflammatory activity of quinones, terpenoids and their derivatives
Přibylová, Marie ; Vaněk, Tomáš (advisor) ; Smrček, Stanislav (referee) ; Hájek, Miroslav (referee)
Plant compounds play an important role in human medicine. They are a source of new drugs or serve as an inspiration for drugs' development. This thesis presents a study about syntheses of derivatives and biological activities of two groups of natural products, quinones and terpenoids. Terpenoids are plant secondary metabolites which are known for their antimicrobial, anti-inflammatory and anti-tumoral activities. We have focused on two representatives, paclitaxel and carvacrol. GnRH-paclitaxel anti-tumor conjugates potentially suitable for targeted delivery to cancer cells were prepared. Their antiproliferative activities in vitro were evaluated on MCF-7 cancer cell line and cytotoxicity in rat hepatocytes. Carvacrol and its derivative were tested for its possible anti- inflammatory effect, which was assessed in vitro as their potential to inhibit prostaglandin E2 biosynthesis via cyclooxygenase pathway. Quinones, other targets of the thesis, are well-known for biological activities similar to terpenoids. Thymoquinone, juglone and their derivatives were tested in vitro as inhibitors of cyclooxygenases and 5-lipoxygenase. Derivatives of juglone were prepared to help us to suggest structure-activity relationship of this compound. Thymoquinone and its derivatives were evaluated for their antioxidant capacity...
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Biochemical aspects of study and restoration of aged paintings
Hradilová, Iveta ; Hudeček, Jiří (advisor) ; Smrček, Stanislav (referee)
Every part of a work of art is changing in the course of time. Even simultaneously in its creation, when tempera or oil paint used dry up. Already this process can be considered as a biochemical change in the material. The main goal of a submitted bachelor's thesis is to compile recent knowledge about resins and protein media used in works of art, to describe their composition and, in particular to evaluate the changes they undergo in time after their application on canvas, wooden or metal surfaces and paper to their irrecoverable destruction. In addition, biological degradation of these substances by several species of bacteria, yeasts and fungi is discussed in the last part of this work. Key words: resins, terpenoids, protein media, degradation, oxidation, hydrolysis (In Czech)
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Antiproliferative, antioxidant and anti-inflammatory activity of quinones, terpenoids and their derivatives
Přibylová, Marie ; Vaněk, Tomáš (advisor) ; Smrček, Stanislav (referee) ; Hájek, Miroslav (referee)
Plant compounds play an important role in human medicine. They are a source of new drugs or serve as an inspiration for drugs' development. This thesis presents a study about syntheses of derivatives and biological activities of two groups of natural products, quinones and terpenoids. Terpenoids are plant secondary metabolites which are known for their antimicrobial, anti-inflammatory and anti-tumoral activities. We have focused on two representatives, paclitaxel and carvacrol. GnRH-paclitaxel anti-tumor conjugates potentially suitable for targeted delivery to cancer cells were prepared. Their antiproliferative activities in vitro were evaluated on MCF-7 cancer cell line and cytotoxicity in rat hepatocytes. Carvacrol and its derivative were tested for its possible anti- inflammatory effect, which was assessed in vitro as their potential to inhibit prostaglandin E2 biosynthesis via cyclooxygenase pathway. Quinones, other targets of the thesis, are well-known for biological activities similar to terpenoids. Thymoquinone, juglone and their derivatives were tested in vitro as inhibitors of cyclooxygenases and 5-lipoxygenase. Derivatives of juglone were prepared to help us to suggest structure-activity relationship of this compound. Thymoquinone and its derivatives were evaluated for their antioxidant capacity...
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Biochemical aspects of study and restoration of aged paintings
Hradilová, Iveta ; Hudeček, Jiří (advisor) ; Smrček, Stanislav (referee)
Every part of a work of art is changing in the course of time. Even simultaneously in its creation, when tempera or oil paint used dry up. Already this process can be considered as a biochemical change in the material. The main goal of a submitted bachelor's thesis is to compile recent knowledge about resins and protein media used in works of art, to describe their composition and, in particular to evaluate the changes they undergo in time after their application on canvas, wooden or metal surfaces and paper to their irrecoverable destruction. In addition, biological degradation of these substances by several species of bacteria, yeasts and fungi is discussed in the last part of this work. Key words: resins, terpenoids, protein media, degradation, oxidation, hydrolysis (In Czech)
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Epiphytic species of the Lecanora subfusca group in the Czech Republic
Malíček, Jiří ; Palice, Zdeněk (advisor) ; Guttová, Anna (referee)
- 4 - ABSTRACT During the revision of epiphytic species of the Lecanora subfusca group in the Czech Republic, nine taxa have been recorded. L. cinereofusca and L. exspersa are reported for the first time from the country. L. circumborealis has been excluded from the list of Czech lichens. L. cinereofusca and L. horiza could be considered as extinct. L. rugosella and L. subrugosa are regarded as extreme morpholocial forms from L. chlarotera and L. argentata. These morphotypes corelate with ecological conditions: substrate (nutrient enriched bark) and habitat (eutrophisation effect). In case of L. subrugosa, this speculation was confirmed by molecular data (ITS rDNA sequences). Several new secondary metabolites have been discovered during the detailed research of chemical lichen compounds. These substances belonging to terpenoids are taxonomically important and very helpful for distinguishing single species. The abundance of L. allophana and L. chlarotera has decreased during last decades. Contrarily, L. pulicaris expanded slightly. The main reasons of changes in distribution are air pollution and acidification of substrates as the impact of acid rains. The rate of substrate acidification has been shown on example of L. pulicaris. In the past, this lichen predominated on acid-barked porophytes. Nowadays, it...
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