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Antimicrobial aktivity of cannabis extract in pathogens causing skin disease
Pařízek, Štěpán ; Fraňková, Adéla (advisor) ; Klouček, Pavel (referee)
Diseases caused by microbes are worldwide cause of morbidity and public health risks. Despite undisputed global benefits of antibiotics, the occurrence of infections caused by antibiotics-resistant bacteria becomes more frequent. This can be attributed to increased consumption of antibiotics in the long term, but also to their inappropriate use. Appart from that, progress in the field of synthetic antibacterial drugs research is dramatically stagnating in recent decades, plus the the antibiotics have bad effects to many bacteria types beneficial to human body. This generates a strong need to seek for natural remedies with similar or better antimicrobial effects. It is known that many plants produce a wide range of secondary metabolites with antimicrobial effects. Such metabilites inhibit growth and reproduction of pathogenic microorganisms by various mechanisms. From explored herbal medicines hemp, traditionally used to cure many diseases, appears to be a suitable alternative to antibiotics.
This thesis focuses on the antimicrobial activity of extracts of six different cannabis genotypes. Extracts with different ratios of cannabinoids have been tested using in vitro microdilution method on selected pathogens, causing skin disease (Staphylococcus spp., Streptococcus spp.).
Results confirmed the antimicrobial activity of all tested extracts. Very good minimum inhibitory concentration was assessed mainly for Streptococcus spp. with a concentration of 4 ug/ml. Extracts NHS4, JB3 and CK3 showed best results against all pathogens, with minimal inhibitory concentrations in the range from 4 to 16 ug/ml. Only extracts of CK2, N3 and JC1 have proven ineffective (MIC 512 ug/ml), because they could not be evaluated by the inhibitory concentration.
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Evaluation of physical properties of rice cultivars grown in Kyrgyzstan
Nádvorníková, Martina ; Banout, Jan (advisor) ; Fraňková, Adéla (referee)
The purpose of this study was to evaluate physical properties of eight staple rice
cultivars grown and consumed in Kyrgyzstan. The objective was to record and discuss
values of several analysis in sub-sections of basic physical characteristics, textural
characteristics, mechanical characteristics and cooking properties. The physical
properties investigated seed dimensions, equivalent diameter, surface area of the grain,
sphericity, aspect ratio, volume of the grain, bulk and solid density, porosity, thousand
kernel weight, hardness of the grain, colour characteristic, optimum cooking time and
water uptake ratio. Those analysis were performed in the laboratory of Czech University
of Life Sciences and given methodology was strictly followed.
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The Application of Essential oils Encapsulated into Nanoclay for Shelf-life Improvement of Fresh Chicken Meat
Vojtíšková, Zuzana ; Klouček, Pavel (advisor) ; Fraňková, Adéla (referee)
This dissertation aims to introduce essential oils as effective antimicrobial substances suitable for food preservation, focusing on the shelf life of meat. Meat is food which is - due to its high nutrient content - susceptible to microbial spoilage. Decaying of meat can be delayed by the selection of appropriate preservation methods. Nowadays there are increasingly used preservative modern methods which differ from classical preservatives procedures mainly in the consideration to the food. As very promising method can be considered preservation by essential oils. In the experimental part of this thesis the effect of encapsulated essential oils into the clay nanoparticles for the shelf life of fresh chicken meat is assessed. For the purpose of the experiment thyme essential oil and oil of savory in two different concentrations (oil:nanoclay - 1:5, 1:10 w/w) were used. Pieces of chicken meat (5 g) were inoculated with Salmonella enteritidis (ATCC 13076) and Escherichia coli (ATCC 25922) and then coated with the clay nanoparticles with the encapsulated essential oils. That treated meat was stored at 4 °C and assessed at 1st, 7th and 14th day of storage, together with three controls. Samples of the chicken meat were explored in terms of microbiological parameters and their inhibitive effect against pathogenic bacteria was examined. Samples were also subjected to sensory analysis, which should provide potential impact of essential oils on the organoleptic characteristics of meat. The results confirmed the antimicrobial activity of both essential oils against pathogenic bacteria. Thyme essential oil, however, showed greater inhibitory activity compared with oil of savory. Thyme essential oil has reduced in both tested bacteria their number in more than 3.5 log CFU.g-1 compared to the controls. Less favorable results were observed in the case of sensory analysis, because in terms of organoleptic characteristics the concentrations of oils were not accepted positively by the assessors. The samples treated with essential oils had undesirable bitter and pungent taste.
This work confirmed the antimicrobial activity of thyme and savory essential oils, which can be used for preservation of fresh meat. But the real application of the essential oils in food may be significantly limited by their impact on the organoleptic characteristics of the product.
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Selection of cannabis chemotypes suitable for therapeutic use with predominant active substance THC
Michnová, Lenka ; Fraňková, Adéla (advisor) ; Klouček, Pavel (referee)
During recent years the possible medical application of cannabis has been discussed more and more. It turns out, that the active substances (cannabinoids cannabidiol and tetrahydrocannabinol) have a significant potential in medicine and do not have to be only misused as a recreational drug. The Department of Crop Production (Faculty of Agrobiology, Food and Natural Resources) is the first institution with granted permission to legally cultivate cannabis, with higher THC content than 0,3 %, for research purposes.
The first part of literate review recapitulates the basic knowledge about the cannabis, its biologically active substances and current legislation. The second part describes the endocannabinoid system and utilization of cannabis in the field of medicine. This thesis aims to evaluate the THC and CBD content in seven different cannabis cultivar strains (Nurse Jackie, Conspiracy Kush, Jillybean, Jack Cleaner 2, Jack Skellington, Nordle and National Health Service). The cannabis plants were cultivated in three cultivation cycles. The content of active substances in dried and homogenised inflorescence was analysed by gas chromatography with flame ionization detection (GC-FID) according to UN methodology. Based on the analysis, the appropriate genotypes were chosen, which are in accordance of Regulation 236/2015 Sb. and needs of the patients.
According to results it was found, that all seven analysed cultivars are suitable for medical utilization regarding the content of THC and CBD. The highest average content of THC was measured by cultivar Jack Cleaner 2. On the other hand, the lowest THC content was established by cultivar Nordle. It was demonstrated, that the differences in THC content are connected rather to genotype variation than cultivation factors. The main goal of the thesis was to discover which of the seven cultivars will be stable regarding not only THC and CBD content, but also the crop yield. In those regards the research shows the cultivar Jack Cleaner 2 and Nurse Jackie as the most suitable. Preliminary results indicate that these two cultivar strains would be the most suitable for the therapeutic purposes.
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Quality of potato chips made of potatoes treated with carvone
Gildainová, Dana ; Klouček, Pavel (advisor) ; Fraňková, Adéla (referee)
This diploma thesis evaluates the ability of a monoterpene S-carvone (main component of caraway oil) to inhibit the sprouting of stored potatoes intended for further processing into a food products. Then it evaluates the influence of carvone's special treatment on selected qualitative parameters of potato chips.
For this experiment, two concentrations of carvone were selected (8 and 32 microliters per liter), applied altogether 4-times on stored potatoes within 3-week intervals. For this application a modified chromatograph was used to ensure a uniform dispersion of the compound. Special treatment was being done for a period of 10 minutes, while each variant of this treatment had 3 repetitions. After each treatment the inhibition effect of carvone on the growth of sprouts was evaluated. Also, there was an evaluation of the content of reducing sugars using the Luff-Schoorl method. Potato chips were repeatedly produced from the treated potatoes. Instrumental measuring of the texture of these potato chips was done on a testing device Instron. Potato chips were also a subject to a sensory evaluation to find out the degree of influence on organoleptic properties.
On the basis of the results, the inhibition effect had been confirmed only in the treatment by carvone with a concentration 32 microliters per liter. The variant of treatment by 8 microliters per liter provided the same results as the control variant. Content of reducing sugars in a tuber had not been influenced by a treatment by S-carvone. During the instrumental measuring of textural properties, a significant difference between control and variants treatment by carvone had been confirmed only after the second and fourth treatment. These chips had shown higher maximal strength needed for crunching of potato chip in comparison with the control. On the basis of the sensory profile of potato chips, no organoleptic properties had been influenced even after the fourth treatment with carvone of stored potatoes. Essential oils and its active substances represent a suitable substitution for used synthetic substances, because there had been recognized no negative effect of carvone on the qualitative parameters.
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The application of plant-derived biologically active substances for shelf-life improvement of elderflower syrup
Grosmanová, Anna ; Klouček, Pavel (advisor) ; Fraňková, Adéla (referee)
The aim of this thesis was to find biologically active substances that would be
suitable as natural conservatives for herbal sirups, in our case elderflower sirup.
Because esential oils are among biologically active substances well known for
their antimicrobial aktivity we chose thyme, lemongrass and clove bud essencial oils to
be tested on the eldeerflower sirup.
Potencial use in a private small scale production was one of the reasons for this
particular topic and therefore its technological inovation.
The emulgated essential oil was mixed with the sirup and observed for 14 days
for the colonies forming units (CFU) which was determined by the drop plate technique.
Cultivation was done at a room temperature 22° C as its expected by the consumer that
sirups may be stored this way. After the cultivation the numbers of colony forming units
were counted and turned into a logaritmic value.
Clove essential oil proved a significant difference between control specimen and
the essential oil preserved specimen. Statistically remarkable corelation was found also
between different concentrations. As well as clove, lemongrass essencial oils proved
certain antimicrobiologial activity also with statistical significance. Thyme essential oil
proved antimicrobiological activity as well only with no significant difference between
concentrations.
Essential oils are suitable as natural conservatives for not only their proven
antimicrobiological activity but also low price and easy application.
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Metody hodnocení environmentálních dat‚ informací a indikátorů: Průzkum efektivity informačních služeb MŽP
BEZK, o.s. Praha ; Univerzita Karlova v Praze, Filozofická fakulta, Ústav informačních studií a knihovnictví, Praha ; Fraňková, Adéla ; Levá, Petra ; Mihalíček, Matouš ; Bilinová, Markéta ; Činčera, Pavel ; Sluková, Petra ; Souček, Martin ; Činčera, Jan ; Papík, Richard
Tato část zprávy pojednává o provedeném průzkumu efektivity informačních služeb Ministerstva životního prostředí. Je členěna do dvou hlavních celků: indikativní části, popisující metodiku projektu, ověřované hypotézy a závěry, a prezentační části. Ta sestává z kapitol: průzkum využití informačních služeb MŽP/CENIA pro výzkum a vývoj, analýza návštěvnosti www stránek, průzkum mezi celostátně působícími nevládními organizacemi, průzkum mezi komerčně působícími subjekty, průzkum mezi učiteli různých stupňů škol a průzkum mezi veřejnými a odbornými knihovnami.
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