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Determination of the effect of dog rose (Rosa canina L.) on the oxidative stability in fresh juices
Borová, Šárka ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis aimed to determine the content of bioactive substances and antioxidant activity in ethanolic extracts of rose hips fruits (Rosa Canina L.). This work verified the possibility of using the rosehip ethanolic extract as an antioxidant to inhibit the oxidation of fresh pear juice. The ethanolic extracts were prepared by extracting rose hips fruits in various ratios of fruits to the volume of 40% ethanol for 7-28 days. After determining the total content of carbohydrates, polyphenols, flavonoids and vitamin C, it was found that, in principle, the range of the defined substances increases with the ratio of rosehip fruit to the volume of ethanol solution as well as with the extraction time. Ethanol rosehip extracts have also been shown to possess significant-high antioxidant activity. The stabilizing effect of rosehip fruit extract against the oxidation of fresh pear juice was determined spectrophotometrically. It was found that rosehip fruit extracts could inhibit the oxidation of fresh pear juice and have the potential as a natural stabilizer of fresh fruit juices.
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Study of the presence of phenolic substances and their antioxidant activity in food products containing rosehip (Rosa canina L.)
Hronová, Vendula ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor's thesis monitored the content of bioactive substances and antioxidant activity in the jams made of the fruit of rose hips (Rosa canina L.). The jams were sweetened with various sweeteners such as cane sugar, beet sugar, erythritol and stevia. Moreover, the rheological properties of jams were determined. The properties of home-made jams prepared from rosehip fruit were compared with the commercial jam. Another aim was to determine whether the by-products received after the production of jams could serve as beneficial sources of bioactive substances after the preparation of water extracts. The content of carbohydrates, polyphenols, flavonoids, and antioxidant activity were determined in jams and extracts spectrophotometrically. Next, the spectrophotometric detection of pectin, the chemical characterization of jams by infrared spectrometry, and the spectrophotometric determination of the jam colour were performed. The concentration of bioactive substances in jams was influenced by the geographical location and the time and weather conditions of harvest. The rheological properties and pectin content of the jams depended on the type of the used sweetener. The assessment of the water extracts prepared from the by-products after jam production and from the dried fruits of rosehip showed the high content of bioactive substances and high antioxidant activity in all tested extracts. The presented work points out that it is possible to prepare jams with superfood properties from the fruit of rose hips and extracts with high antioxidant activity.
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Less conventional botanical sources of cosmetic raw materials
Novotná, Petra ; Vespalcová, Milena (referee) ; Zemanová, Jana (advisor)
The aim of this bachelor’s thesis is an investigation of use of less traditional plant sources in cosmetic industry. This review is focused on black elder (Sambucus nigra), sea buckthorn (Hippophae rhamnoides), quince (Cydonia oblonga), dog rose (Rosa canina), and stinging nettle (Urtica dioica). The substances Isolated from these plants can be used in various cosmetic products. The first section of this search deals with history and botanical characterization of these plants. The next section deals with significant substances contained in these plants and their use not only in cosmetic industry.
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Antimicrobial effect of plant extracts
Konderla, Patrik ; Vespalcová, Milena (referee) ; Veselá, Mária (advisor)
The purpose of this bachelor thesis was to research the possible antimicrobial activity of various extracts of rosehip tea and also determine the antioxidant activity and the concentration of biologically active compounds (polyphenols and flavonoids) in these tea. Teoretical part describes basic information about plant Rosa canina and chemical composition of rosehips, summary of the natural biologically active compounds and general classification of tea. The practical part is focused on detection of antimicrobial activity of tea extracts against bacterial strains Serratia marcescens and Bacillus subtilis as well as spectrophotometrical determination of concentration polyphenols, flavonoids and overall antioxidant activity of these extracts. From the results flow the testing aqueous extracts rosehips tea analysed antimicrobial effects. Also was found, that these extracts has high content of polyphenols and flavonoids.
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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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Bacterial cellulose based facial mask with antioxidant property
Borová, Šárka ; Hoová, Julie (referee) ; Kovalčík, Adriána (advisor)
This final thesis deals with the preparation of a cosmetic facial mask based on bacterial cellulose. The motivation of this work was to prepare a cosmetic mask with antioxidant properties. To obtain bioactive substances with antioxidant activity, extracts from the rosehip fruits (Rosa Canina L.) with different weight dosages of rosehips and different preservatives were prepared. These rosehip extracts were subjected to spectrophotometric methods, thanks to which the total contents of polyphenols, flavonoids and total antioxidant activity were determined. It was proven that the content of the determined substances increases with the proportion of weighted rose hips and the highest contents of antioxidant substances were measured in extracts with a weight of 25 g of rose hips. Subsequently, these selected extracts were modified into several samples of bacterial cellulose. After the modification of the substances, it was demonstrated that bacterial cellulose is a suitable material for absorbing bioactive substances into the structure of individual analyzed samples. It was found that bacterial celluloses in the form of hydrogel and lyophilized bacterial cellulose were able to absorb the largest amount, of bioactive substances with antioxidant properties. On the other hand, the samples of dry bacterial cellulose and bacterial cellulose with an alginate component absorbed active substances the least. Furthermore, analysis using a Visioscope device revealed that the facial cosmetic mask based on bacterial cellulose in the form of hydrogel could potentially have not only antioxidant but also hydrating effects on the skin.
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Study of the presence of phenolic substances and their antioxidant activity in food products containing rosehip (Rosa canina L.)
Hronová, Vendula ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor's thesis monitored the content of bioactive substances and antioxidant activity in the jams made of the fruit of rose hips (Rosa canina L.). The jams were sweetened with various sweeteners such as cane sugar, beet sugar, erythritol and stevia. Moreover, the rheological properties of jams were determined. The properties of home-made jams prepared from rosehip fruit were compared with the commercial jam. Another aim was to determine whether the by-products received after the production of jams could serve as beneficial sources of bioactive substances after the preparation of water extracts. The content of carbohydrates, polyphenols, flavonoids, and antioxidant activity were determined in jams and extracts spectrophotometrically. Next, the spectrophotometric detection of pectin, the chemical characterization of jams by infrared spectrometry, and the spectrophotometric determination of the jam colour were performed. The concentration of bioactive substances in jams was influenced by the geographical location and the time and weather conditions of harvest. The rheological properties and pectin content of the jams depended on the type of the used sweetener. The assessment of the water extracts prepared from the by-products after jam production and from the dried fruits of rosehip showed the high content of bioactive substances and high antioxidant activity in all tested extracts. The presented work points out that it is possible to prepare jams with superfood properties from the fruit of rose hips and extracts with high antioxidant activity.
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Determination of the effect of dog rose (Rosa canina L.) on the oxidative stability in fresh juices
Borová, Šárka ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis aimed to determine the content of bioactive substances and antioxidant activity in ethanolic extracts of rose hips fruits (Rosa Canina L.). This work verified the possibility of using the rosehip ethanolic extract as an antioxidant to inhibit the oxidation of fresh pear juice. The ethanolic extracts were prepared by extracting rose hips fruits in various ratios of fruits to the volume of 40% ethanol for 7-28 days. After determining the total content of carbohydrates, polyphenols, flavonoids and vitamin C, it was found that, in principle, the range of the defined substances increases with the ratio of rosehip fruit to the volume of ethanol solution as well as with the extraction time. Ethanol rosehip extracts have also been shown to possess significant-high antioxidant activity. The stabilizing effect of rosehip fruit extract against the oxidation of fresh pear juice was determined spectrophotometrically. It was found that rosehip fruit extracts could inhibit the oxidation of fresh pear juice and have the potential as a natural stabilizer of fresh fruit juices.
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Využití plodů růže šípkové při výrobě ovocných vín
Barnáková, Zuzana
The aim of the bachelor thesis was to study the available literature dealing with fruit wines and to emphasize the technology of fruit wines making and rosa canina wine making, to describing composition of dog rose wines, to study of the legislative conditions for production and sale of fruit wines on the Slovak and Czech Republic markets with the emphasis and next to describe and evaluate current assortment of dog rose wines. Rose canina is a fruit with a high content of ascorbic acid and polyphenolic substances, which is then transferred to the character of wines. Wines are full of dominance of berry and dried fruits. Main differences between analyzed wines were based on own style of each winemaker. Low of the Slovak and Czech Republic deals with fruit wines just in general. Due to the specificity of dog rose wines and especially the different processing methods based on low water content in fruits and water adding, the legislative treatment of the production of these wines is insufficient. As a complementary aim of the bachelor thesis, we have determined the preparation and evaluation of our own samples of dog rose wines that fermented in two different types of yeast and the finding if there is a significant difference between them and their comparison with the wines available on the market. In the overall impression of sensory analysis, there was no detectable difference between our two wines.
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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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