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Isolation of active substances with antioxidative properties from lignocellulosic waste
Jurová, Karolína ; Vítová, Eva (referee) ; Kovalčík, Adriána (advisor)
This thesis focuses on isolating active substances with antioxidant properties from lignocellulosic wastes. This work aimed to modify bacterial cellulose (BC) with extracts from grape pomace, which show high antioxidant activity. Grape pomace belongs to the group of lignocellulosic wastes with high content of bioactive compounds such as polyphenols, which contribute significantly to antioxidant efficacy. This work tested the hypothesis that grape extracts can provide antioxidative efficiency to BC. Grape pomace extracts were prepared from grape pomace frozen and lyophilized using a 70% acetone, a 70% ethanol or a 50% ethanol solvent. The highest values of antioxidant activity were determined for the lyophilized extract prepared by extracting grape pomace with 70% acetone. The extracts were further used to modify bacterial cellulose in the form of films (dry BC) and hydrogels (wet BC). It was shown that both forms of BC could be effectively modified using grape pomace extracts, but BC hydrogel achieved higher antioxidant activity compared to BC film. Furthermore, BC with antioxidant activity can be used in various food, cosmetics, and medicine applications.
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Biological activity of plant metabolites XXIII. Alkaloids of Corydalis cava (L.) SCHWEIGG. & KÖRTE and their effect on acetylcholinesterase and butyrylcholinesterase.
Kaluzsná, Blanka ; Opletal, Lubomír (advisor) ; Cahlíková, Lucie (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Bc. Blanka Kaluzsná Supervisor: Prof. RNDr. Lubomír Opletal, CSc. Title of Diploma Thesis: Biological activity of plant metabolites XXIII. alkaloids of Corydalis cava (l.) Schweigg. & Körte and their effect on acetylcholinesterase and butyrylcholinesterase An ether extract which contained tertiary basic alkaloids was prepared from the dry bulb of Corydalis cava (L.) SCHWEIGG. & KÖRTE. A subfaction labeled 2/B was obtained by column chromatography and crystallization. Three alkaloids were isolated by preparative TLC and they were identified by GC/MS and 1 H a 13 C NMR analyzes as (+)-canadine, (+)-tetrahydropalmatine and domestine. Isolated alkaloids were tested by spectrophotometric Ellman method for inhibitory activity against human erythrocyte acetylcholinesterase (HuAChE) and plasma butyrylcholinesterase (HuBuChE). In comparison with the refernce substances, from these isolated alkaloids only (+)-canadine showed an relatively high inhibitory activity against HuAChE (12,4 µM). (+)-Tetrahydropalmatine and (+)-domestine had no significant inhibitory activity in this direction, against both HuAChE and HuBuChE. Key words: Corydalis cava, (+)-canadine, (+)-tetrahydropalmatine,...
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