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Study of the antimicrobial effects of selected spices
Kalábová, Jana ; RNDr.Eva Dvořáčková (referee) ; Voběrková, Stanislava (advisor)
The antimicrobial effects of cinnamon, clove and ginger (grand and fresh) extracts against Bacillus subtilis, Aspergillus niger and Pichia fermentans were studied in this thesis. Selected spices were extracted in three solvents (ethanol, water and ethyl acetate) and inhibition effect on tested microorganisms was studied using two methods disc diffusion and broth dilution methods. The antioxidant activity and total polyphenolic compounds from spices were also determined. The results showed that cinnamon and clove extracts in ethyl acetate and ethanol were a promising antimicrobial substances for all tested microorganisms. Combination of cinnamon and clove especially ethyl acetate extracts showed an aditive effect. However, in the case of broth dilution method, fresh ginger inhibited bacterial growth under optimal growth conditions of Bacillus subtilis (35 °C, pH 7, 250 rpm). Minimum inhibitory concentration (MIC) values for all susceptible microorganisms was determined 8,3 mg/ml. The highest amounts of polyphenolic substances were found in cinnamon and clove ethanol extract and this result was in correlation with antioxidant activity.
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Preparation of edible antimicrobial packaging
Kozubová, Petra ; Dzurická, Lucia (referee) ; Skoumalová, Petra (advisor)
This bachelor’s thesis is focused on preparation and characterization of eatable packaging. Eatable packaging consists of two components, antimicrobial component and base of packaging. The task of eatable packaging is to protect product against antimicrobial attack and to extend durability of the product. As antimicrobial components were used water and oil extracts of several herbs (mint, nettle, lavender, cinnamon, cloves, vanilla, ginger and rhinoceros). Oil extracts were also encapsulated into liposomes for better application. Firstly, concentrations of polyphenoles and antioxidants of extracts were determined. Oil extract of clove contained the highest concentration of both determined substances. Encapsulation efficiency, stability and size of liposomes were tested too. All prepared liposomes were stable and relatively of the same size. Also high encapsulation efficiency was observed. Next, antimicrobial activity of prepared extracts and liposome particles against yeast Candida glabrata and two bacteria strains Escherichia coli and Staphycococcus epidermidis was tested and the high antimicrobial activity reported mainly all tested liposomes. Then alginate, chitosan and carboxymethylcellulose and their combinations respectively were used as bases of packaging. Created film had to meet several parameters, especially suitable sensory properties such as pleasant taste and smell, as well as invisibility, gloss, affordability and suitable manipulability. Combination of 2% carboxymethylcellulose and 1% alginate in a ration of 2:1 with liposomes of mint as antimicrobial component achieved the best results.
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Koření z čeledi miříkovitých a jejich využití v potravinářském průmyslu
Halodová, Tereza
The diploma thesis "Spices of the Apiaceae Family and Their Use in the Food Processing Industry" focuses on the characteristics of medicinal, aromatic, and spice herbs. The the-sis examines the legislation related to spices, plant substances, and their use in the food processing industry, particularly in the production of essential oils. The thesis also describes the methods of essential oil extraction and the norms for determining their con-tent. The thesis provides a detailed description of the Apiaceae family, which includes significant plant species used as spices. The practical part of the thesis includes a compa-rison and analysis of specific spices from the Apiaceae family, such as Anise, Fennel, Caraway, Dill, and Coriander. The content of essential oils in these spices was determined using the steam distillation method (based on Český lékopis 2017). Samples of the spices were obtained from four different manufacturers. The discovered content of essential oils ranged from 0.66 ml/100 g to 5.26 ml/100 g.
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Chromatografická analýza rostlin a produktů spojených s výrobou absinthu a testování odpadů z výroby jako možného zdroje biopesticidů
BEDNÁŘ, Jan
This thesis deals with the analysis of herbs traditionally used for the absinth production: Pimpinella anisum, Foeniculum vulgare and Artemisia absinthium. The suitable GC-MS methods were developed and validated and they were used for the determination of the volatile substances content in essential oils and dried herbs which are available at the Czech market. Another aim of this study was to determine the content of t anethole and -thujone during the distillation of absinth in both laboratory and industrial scale. Finally, distillation residues were tested on Spodoptera litoralis larvae for potential pesticidal effects at VÚRV.
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Preparation of edible antimicrobial packaging
Kozubová, Petra ; Dzurická, Lucia (referee) ; Skoumalová, Petra (advisor)
This bachelor’s thesis is focused on preparation and characterization of eatable packaging. Eatable packaging consists of two components, antimicrobial component and base of packaging. The task of eatable packaging is to protect product against antimicrobial attack and to extend durability of the product. As antimicrobial components were used water and oil extracts of several herbs (mint, nettle, lavender, cinnamon, cloves, vanilla, ginger and rhinoceros). Oil extracts were also encapsulated into liposomes for better application. Firstly, concentrations of polyphenoles and antioxidants of extracts were determined. Oil extract of clove contained the highest concentration of both determined substances. Encapsulation efficiency, stability and size of liposomes were tested too. All prepared liposomes were stable and relatively of the same size. Also high encapsulation efficiency was observed. Next, antimicrobial activity of prepared extracts and liposome particles against yeast Candida glabrata and two bacteria strains Escherichia coli and Staphycococcus epidermidis was tested and the high antimicrobial activity reported mainly all tested liposomes. Then alginate, chitosan and carboxymethylcellulose and their combinations respectively were used as bases of packaging. Created film had to meet several parameters, especially suitable sensory properties such as pleasant taste and smell, as well as invisibility, gloss, affordability and suitable manipulability. Combination of 2% carboxymethylcellulose and 1% alginate in a ration of 2:1 with liposomes of mint as antimicrobial component achieved the best results.
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Výskyt a eliminace čmelíka kuřího v chovech kura nosného typu v ČR
Rádsetoulalová, Iva
In a practical part of my thesis I monitored mortality of poultry red mite (Dermanyssus gallinae), caused by selected essential oils. There were used six essential oils: clove bud, lavender, cinnamon, rosemary, skin of Brazilian oranges, peppermint. The acaricidal activity of six plant essential oils against poultry house-collected red mites was examined using direct contact method by glass vial bioassay, at six different concentrations: 0.5; 0.25; 0.12; 0.06; 0.03; 0.015 microlitre/cm2. Always eleven glass vials per each concentration and oil and controls (without essential oils) were used. Oils were dissolved in metanol or distilled water or Tween 85 with water. Twenty movable poultry red mites all their stages of development were placed on the filter paper impregnated by essential oil at the bottom of the glass vials. The mortality of the poultry red mites in the glass vials was measured after 24 h. All used essential oils caused mortality of poultry red mite. The average mortality in the controls were 2 %. The highest mortality was observed with clove buds essential oil and cinnamon essential oil at concentrations of 0.5 and 0.25 microlitre/cm2.
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Variabilita obsahu a složení silic levandule lékařské z různých proveniencí
Fojtíková, Lucie
The aim of this work was the determination of variability of the essential oil content in lavender obtained from different sources. The results indicate that significant differences were found both in the essential oil content and in its composition. Only the samples of the Lavandula angustifolia P. MILL (L. officinalis CHAIX) were used to obtain the essential oils. According to the Czech Pharmacopoeia 2014, the drug (lavender flowers) should contain at least 1.3 ml of essential oil in 100 g of anhydrous drug and lavender essential oil should contain following ingredients: limonene < 1.0%, cineol < 2.5% (eucalyptol), 3-octanone < 2.5%, camphor < 1.2%, linalol 20.0% to 45.0%, linalylacetate 25.0% to 46.0%, terpinene-4-ol 1.2% to 6.0%, lavandulylacetate > 1.0%, lavandulol > 0.1%, α-terpineol < 2.0%. In addition, five microbial lavender samples of different provenances were determined by microbiological purity of the drug, whereby the amount of colonies per 1 ml was determined for the total number of microorganisms, spore microorganisms, enterobacteria, yeasts and fungi.
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Study of the antimicrobial effects of selected spices
Kalábová, Jana ; RNDr.Eva Dvořáčková (referee) ; Voběrková, Stanislava (advisor)
The antimicrobial effects of cinnamon, clove and ginger (grand and fresh) extracts against Bacillus subtilis, Aspergillus niger and Pichia fermentans were studied in this thesis. Selected spices were extracted in three solvents (ethanol, water and ethyl acetate) and inhibition effect on tested microorganisms was studied using two methods disc diffusion and broth dilution methods. The antioxidant activity and total polyphenolic compounds from spices were also determined. The results showed that cinnamon and clove extracts in ethyl acetate and ethanol were a promising antimicrobial substances for all tested microorganisms. Combination of cinnamon and clove especially ethyl acetate extracts showed an aditive effect. However, in the case of broth dilution method, fresh ginger inhibited bacterial growth under optimal growth conditions of Bacillus subtilis (35 °C, pH 7, 250 rpm). Minimum inhibitory concentration (MIC) values for all susceptible microorganisms was determined 8,3 mg/ml. The highest amounts of polyphenolic substances were found in cinnamon and clove ethanol extract and this result was in correlation with antioxidant activity.
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Bioaktivní látky používané k prodloužení údržnosti mléka a mléčných výrobků
Řezníčková, Kateřina
The aim of my work was to investigate bioactive substances, which are able to extend the shelf life of milk and dairy products. The work deals with the description of the spe-cies of lactic acid bacteria and their products, which can considered acid, hydrogen pe-roxide, and especially bacteriocins that are in the thesis divided into classes and described. In the second part of the thesis deals with bioactive substances, which are of plant origin. Finally, the are described dairy products that naturally contain these bio-active substances.
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