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Preparation and testing of application forms for natural antimicrobial substances
Vajglová, Klára ; Bokrová, Jitka (referee) ; Márová, Ivana (advisor)
The goal of this bachelor thesis was the study of antimicrobial and antioxidant effects of some herbal extracts: cloves, nettle, sage, chamomile, rosemary, elderberry, lavender and also lysozyme. Further, herbal extracts effect on Gram positive and Gram negative bacteria were compared. In the theoretical part were briefly characterized lysozyme, polyphenols, flavonoids and selected strains of microorganisms. In the experimental section characterization of herbs with antimicrobial and antioxidant effect was proved. Particles containing herbal extracts were prepared and encapsulation efficiency was determined. In some of tested herbs encapsulation efficiency of up to 80% was reached. Stability of the prepared liposomes was tested in the model digestive conditions and after 1 week and 1 month incubation period in model foods. Antimicrobial activity was tested on selected representatives of Gram negative and Gram positive bacteria. Gram positive bacteria were more sensitive to herbal extracts and liposomes containing encapsulated herbs, while lysozyme exhibited higher effect to Gram negative bacteria. Prepared particles with encapsulated antimicrobial extracts are especially suitable for use in the food industry.
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Use of cell cultures to test cytotoxicity of natural substances
Blažková, Veronika ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
This thesis is aimed on study of cell cultures, primarily on introduction of techniques for cultivation of human cells and optimization of their usage in cytotoxicity tests. The thesis is aimed preferably on natural substances and liposomes that are suitable to be used in cosmetics. Theoretical part contains literature review focused on overview of cell cultures, appropriate cultivation conditions for in vitro testing and summary of cytotoxicity tests. Experimental part contains characteristics of natural extracts with antimicrobial effect in terms of content of polyphenols, flavonoids and antioxidant activity. Further, these extracts were encapsulated into the liposomes. Encapsulation effectivity was determined. Distribution of particles size by dynamic light scattering and finally also stability of prepared particles were also determined. Long-term stability in water and gel environment was tested too. This thesis also contains study of optimization of cell culture of human skin keratinocytes cultivation and use of those cells for testing cytotoxicity of selected natural substances by MTT method.
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Preparation of some application formula of antimicrobial substances
Krempaský, Kamil ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The main aim of this study is to determine antimicrobial activity of herbal extracts and also encapsulate these extracts and lysozyme to liposomes. The extracts were prepared from above ground part of wormwood (Artemisia absinthium), aerial part of breckland thyme (Thymus serpyllum), the root of purple coneflower (Echinacea purpurea), liquorice (Glycyrrhiza glabra), corolla of pot marigold (Calendula officinalis) and berries of sea buckthorn (Hippophae rhamnoides). In all extracts antioxidant activity and the amount of total polyphenols and flavonoids was determined. All of these extracts and also lysozyme were used for encapsulation to liposomes. Prepared liposomes were then tested for their stability. Further, encapsulated as well as free extracts were tested for their antimicrobial activity on Escherichia coli, Serratia marcescens, Micrococcus luteus and Bacillus subtilis. Extract from Echinacea purpurea showed the highest antimicrobial activity.
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Bioactive substances of rose hip
Ďubašáková, Mária ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The aim of this master´s thesis was to determine the concentration of bioactive substances such as total polyphenols and flavonoids as well as the total antioxidant capacity in tea extracts from Rosa canina. In the second part, an experiment was found to detect antimicrobial activity and an effective concentration of ethanol against selected bacteria. The theoretical part is focused on description of natural antioxidants and their effect on free radicals, description of tea, description of rose hazel and possibilities of spectrophotometric determination of natural substances and eventually basic distribution of bacteria. In the experimental part, ethanol and aqueous extracts were prepared in which the total number of polyphenols, flavonoids and antioxidant effects. The results of the determination of polyphenols and flavonoids show that the solvent with ethanol is more suitable for flower fermentation and water is more suitable for dropping the rose. Comparison of the antioxidant activity of macerates showed no significant differences; slightly higher antioxidant activity showed macerates from pink flowers. The extracts showed antimicrobial activity against Micrococcus luteus and slightly against Bacillus cereus. The highest antimicrobial activity was determined for the micrococcus luteus
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Optimization of echinacea drops production technology
Boberová, Jana ; Vespalcová, Milena (referee) ; Zemanová, Jana (advisor)
This diploma thesis deals with the production of herbal drops from Echinacea and the determination of the content of selected active substances. In the theoretical part, the taxonomic classification of echinacea, its botanical characteristics and growing conditions are mentioned. The history of cultivation and uses of this plant are also mentioned. An important chapter of the theoretical part is the chemical composition of the plant and differences in composition between individual cultivars of Echinacea. Methods for obtaining active substances and their determination are also mentioned. The last chapter is devoted to the technology of production of echinacea drops. In the experimental part, the extraction was optimized for dried flowers and roots of E. purpurea. The following extraction system was determined for the flowers: 40% ethanol, time 6 hours, weight to solvent ratio 1:10 and room temperature. For the roots, 20% ethanol and a time of 24 hours, a ratio of 1:10 and room temperature were evaluated as the best conditions. Furthermore, the best extracts were prepared, in which the content of total phenolic substances was set at 0.799-0.839 mg/ml, then the antioxidant activity was determined in the range from 116 to 242 µg T/ml, and finally the analysis of aromatic substances was performed by HS-SPME-GC-MS. Two commercial samples were also tested to compare the prepared extracts.
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Study of rose hip bioactive compounds
Konderla, Patrik ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
Purpose of this thesis was research the content of biologically active substances in herbal rosehip extracts and also determination of antimicrobial and antioxidant activity of these extracts. Teoretical part describes informations about Rosa canina L., detailed specification of biologically active substances, specification of antioxidation and overview of methods determine antioxidant compound and antimicrobial activity. In the practical part was by combination of different solvents, procedures and herbal materials, made 21 extracts of Rosa canina L.. From measuring of these extracts, was made extraction curves and also was determined antimicrobial efficiency against bacterial strains Serratia marcescesns, Bacillus subtilis, Bacillus cereus and Micrococcus luteus. Results shows, that also all extracts has some antimicrobial activity, but only against microorganisms Micrococcus luteus and Bacillus cereus. Also was found that bud extracts contains more bioactive compounds soluble in ethanol, meanwhile rose hip extracts contains more bioactive compounds soluble in water.
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Možnosti inovace náplní u čokoládových cukrovinek
Franková, Michaela
The focus of the master's thesis entitled Possibilities of filling innovation in chocolate confectionery is on the production of chocolate and pralines using herbal extracts as part of the fillings. The literary review delves into the processes of chocolate and praline production, types of fillings, and potential defects that may occur in pralines or chocolate. The second part of the theory deals with the extraction methods used to obtain herbal extracts and the properties and applications of herbal extracts, particularly peppermint in the food and confectionery industry. The practical part of the thesis is concerned with the production of pralines with six different types of fillings. A variant with a dark chocolate shell containing white chocolate ganache and cream was used as a control. The other variants, besides the same ganache, contained an addition of one of the following aromatic ingredients: peppermint essential oil, peppermint tincture, dried peppermint, fresh peppermint, or peppermint-flavoured paste. During the sensory analysis, the sensory profile of each praline variant was created, and the relevant descriptors were compared. Variant 2 with peppermint essential oil was evaluated as the best in descriptor overall impression (p<0.05). The worst impression among evaluators was left by variant 5 containing fresh peppermint (p<0.05). The presence of foreign taste in the product strongly influenced the evaluation of this variant, as identified by 64% of the evaluators. Total microbial counts, counts of coliform bacteria and E. coli bacteria, and colonies of mould and yeast were determined during the microbiological analysis. Microbiological analysis was performed on input raw materials, and microorganisms were further monitored in six praline variants over four samplings during six weeks of storage at 16°C. During storage, the strength of chocolate pralines was analyzed using the Tiratest 27 025. The measured results ranged from 1.90–11.82 N. The highest hardness was observed in all variants, except variant 5, after four weeks of storage. The last analysis performed was the measurement of the water activity of pralines, which ranged from values of 0.788–0.859.
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Optimization of echinacea drops production technology
Boberová, Jana ; Vespalcová, Milena (referee) ; Zemanová, Jana (advisor)
This diploma thesis deals with the production of herbal drops from Echinacea and the determination of the content of selected active substances. In the theoretical part, the taxonomic classification of echinacea, its botanical characteristics and growing conditions are mentioned. The history of cultivation and uses of this plant are also mentioned. An important chapter of the theoretical part is the chemical composition of the plant and differences in composition between individual cultivars of Echinacea. Methods for obtaining active substances and their determination are also mentioned. The last chapter is devoted to the technology of production of echinacea drops. In the experimental part, the extraction was optimized for dried flowers and roots of E. purpurea. The following extraction system was determined for the flowers: 40% ethanol, time 6 hours, weight to solvent ratio 1:10 and room temperature. For the roots, 20% ethanol and a time of 24 hours, a ratio of 1:10 and room temperature were evaluated as the best conditions. Furthermore, the best extracts were prepared, in which the content of total phenolic substances was set at 0.799-0.839 mg/ml, then the antioxidant activity was determined in the range from 116 to 242 µg T/ml, and finally the analysis of aromatic substances was performed by HS-SPME-GC-MS. Two commercial samples were also tested to compare the prepared extracts.
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Impact of post-harvest processing, geographical locality and production year on quality of selected medicinal plants
Burdějová, Lenka ; Polovka, M. ; Pořízka, J.
This study deals with the assessment of the impact of post-harvest treatment, geographical location and production years on 32 selected characteristics of medicinal plants grown in the Czech Republic. Dimethyl sulfoxide herbal extracts characteristics were evaluated by spectroscopic and chromatographic techniques. The results were processed by analysis of variance and multivariate statistical tools. Obtained results clearly proved the successful differentiation of herbal samples by means of canonical discrimination analysis according to post-harvest treatment (100%), geographical origin (82.9%) and production year (96.1%) confirming that studied factors may have significant effect on quality of medicinal plants.
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Bioactive substances of rose hip
Ďubašáková, Mária ; Skoumalová, Petra (referee) ; Veselá, Mária (advisor)
The aim of this master´s thesis was to determine the concentration of bioactive substances such as total polyphenols and flavonoids as well as the total antioxidant capacity in tea extracts from Rosa canina. In the second part, an experiment was found to detect antimicrobial activity and an effective concentration of ethanol against selected bacteria. The theoretical part is focused on description of natural antioxidants and their effect on free radicals, description of tea, description of rose hazel and possibilities of spectrophotometric determination of natural substances and eventually basic distribution of bacteria. In the experimental part, ethanol and aqueous extracts were prepared in which the total number of polyphenols, flavonoids and antioxidant effects. The results of the determination of polyphenols and flavonoids show that the solvent with ethanol is more suitable for flower fermentation and water is more suitable for dropping the rose. Comparison of the antioxidant activity of macerates showed no significant differences; slightly higher antioxidant activity showed macerates from pink flowers. The extracts showed antimicrobial activity against Micrococcus luteus and slightly against Bacillus cereus. The highest antimicrobial activity was determined for the micrococcus luteus
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