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Study of preservative systems for cosmetics
Šmétková, Zuzana ; Vítová, Eva (referee) ; Zemanová, Jana (advisor)
The aim of this diploma thesis was to prove the antimicrobial actvivity of the selected syntetic preservatives used in cosmetics, such as methylparaben, butylparaben, phenoxyethanol, bronopol, imidazolidinyl urea and methylisothaizolinone, in different concentrations (up to the highest permitted concentration and in increased concentrations), and of some essential oils, which are possible to use in cosmetics (essential oil from Eucalyptus globulus, Pimpinella anisum, Lavandula officinalis, Rosmarinus officinalis, Foeniculum vulgare, Mentha piperita, Juniperus communis and Pinus sylvestris). The effect was investigated in every preservative system alone, in order to evaluate the spectrum and the rate of each one. As indicator microorganism was chosen Bacillus subtilis and Penicillium chrysogenum. The used methods was disk difusion method and modify difusion method. From synthetic preservatives had the best effects bronopol, imidazolidinyl urea and methylisothiazolinone. From chosen natural antimicrobails had the effect against both indicator microorganisms the Mentha piperita, Foeniculum vulgare and Juniperus communis extracts.
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Potential microbial hazards in actual cosmetology trends - bio, vegan, raw
Jančíková, Simona ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
Bio-, vegan- and raw-cosmetics are continually more popular type of cosmetic products caused by an absence of synthetic and preservative substances but at the same time there is an increased probability of microbial contamination. The main aim of this thesis is a practical findings of potential microbiological contamination using a challenge test and a determination of any active ingredients in the cosmetic preparations. The legislation of cosmetic preparations as well as the information about certificates, which are awarded for bio-, vegan- and raw-cosmetics has been processed in the theory. This section also discusses a composition of vegetable and essential oils, which are used as raw materials in cosmetics production to a great extent and have a positive effect on skin. This thesis also deals with a possible microbiological contamination, listing the most frequently occurred pathogenic microorganisms, which can have a negative influence on consumer health. Operating life of selected samples using the Schülke Koko test by inoculating selected representatives of bacteria, yeasts and molds (Candida glabrata, Escherichia coli, Pseudomonas aeruginosa and Aspergillus niger) are being tested in the practical part. In addition a possible antimicrobial activity which may partially replace an effect of synthetic preservatives in the presence of essential oils is also being tested. Finally any biological active substances were analysed by the gas chromatography, in particular fatty acids contained in the creams.
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Konzervační látky prodlužující uchovatelnost potravin
Koudelná, Radka
This bachelor thesis deals with preservatives, which are necessary part of nowadays, brouse foodstuffs preservation is one of the basic principles how to safe foodstuffs. In my literky part of my bachelor are decribed historical aspects of foodstuff preservation. In the next section there are basic principles preservation and there are thoroughly described preservation that are allowed, but also the ones that are forbidden in the Czech republic. With preservaton using closely related thein maximal allowed limits in foodstuff where there may be health risks. That´s the mason why there i salso a charter delas with legislativ in literaty summary with the attendant this part and methods of preservation assessment in foodstuff. The aim of the practical part thesis was the detection of sodium benzoate and pottasium sorbate kontent in non-alcoholic and alcoholic drinks. These beverages were used for this experiment: Dobrá voda s příchutí bezinka, Hanácká kyselka s příchutí pomeranč, Kofola, Pepsi Twist, Poděbradka Citron, Top Topic Pomeranč, Carling British Cider Cherry, Fanta Shokata, Fizz Cider Strawberry, Kopparberg Limetka a bezinka. In beverages there were detected preservatives contents by the high performance method liquid chromatography. No sample didn´t cross maximal limits allowed as provided by Regulation European Parliament and Council no. 1333/2008. The overall counclusion is that , although producers who couly legislative require limits of preservatives, so from the point of view of the health i tis just chemical substance and consumers should be focused on beverages that don´t include these chemical substances.
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Chemická konzervace potravin a její vliv na lidský organismus
Kučerová, Kateřina
This thesis deals with the problems of chemical preservation, while the first section provides an overview of all conservation methods. The second section summarizes the findings of the general conditions of use and approval of preservatives. Below are the reports permitted or prohibited chemicals that are added to foods during their production. Reports include the characteristics, uses and effects of these substances on the human body. At the same time focus on Czech and European legislation, which gives the values of maximum allowable amount that may be added to food.
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Potential microbial hazards in actual cosmetology trends - bio, vegan, raw
Jančíková, Simona ; Skoumalová, Petra (referee) ; Němcová, Andrea (advisor)
Bio-, vegan- and raw-cosmetics are continually more popular type of cosmetic products caused by an absence of synthetic and preservative substances but at the same time there is an increased probability of microbial contamination. The main aim of this thesis is a practical findings of potential microbiological contamination using a challenge test and a determination of any active ingredients in the cosmetic preparations. The legislation of cosmetic preparations as well as the information about certificates, which are awarded for bio-, vegan- and raw-cosmetics has been processed in the theory. This section also discusses a composition of vegetable and essential oils, which are used as raw materials in cosmetics production to a great extent and have a positive effect on skin. This thesis also deals with a possible microbiological contamination, listing the most frequently occurred pathogenic microorganisms, which can have a negative influence on consumer health. Operating life of selected samples using the Schülke Koko test by inoculating selected representatives of bacteria, yeasts and molds (Candida glabrata, Escherichia coli, Pseudomonas aeruginosa and Aspergillus niger) are being tested in the practical part. In addition a possible antimicrobial activity which may partially replace an effect of synthetic preservatives in the presence of essential oils is also being tested. Finally any biological active substances were analysed by the gas chromatography, in particular fatty acids contained in the creams.
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Study of preservative systems for cosmetics
Šmétková, Zuzana ; Vítová, Eva (referee) ; Zemanová, Jana (advisor)
The aim of this diploma thesis was to prove the antimicrobial actvivity of the selected syntetic preservatives used in cosmetics, such as methylparaben, butylparaben, phenoxyethanol, bronopol, imidazolidinyl urea and methylisothaizolinone, in different concentrations (up to the highest permitted concentration and in increased concentrations), and of some essential oils, which are possible to use in cosmetics (essential oil from Eucalyptus globulus, Pimpinella anisum, Lavandula officinalis, Rosmarinus officinalis, Foeniculum vulgare, Mentha piperita, Juniperus communis and Pinus sylvestris). The effect was investigated in every preservative system alone, in order to evaluate the spectrum and the rate of each one. As indicator microorganism was chosen Bacillus subtilis and Penicillium chrysogenum. The used methods was disk difusion method and modify difusion method. From synthetic preservatives had the best effects bronopol, imidazolidinyl urea and methylisothiazolinone. From chosen natural antimicrobails had the effect against both indicator microorganisms the Mentha piperita, Foeniculum vulgare and Juniperus communis extracts.
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Způsoby prodloužení údržnosti mléčných výrobků
Piskačová, Martina
This thesis discusses the way to extend the shelf-life of dairy products. The first part focuses on mold spoilage of dairy products, types of microorganisms threatening dairy products and the factors that influence the growth of undesirable microorganisms. The second part focuses on the basic heat treatment during technological processing of dairy products that affect their durability. The final part of the work is focused on the effects of antimicrobial substances in milk and dairy products. Above all, the preservatives, antioxidants and bioactive substances.
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