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 Triterpenes are group of biologically active compounds which can be found in higher plants. Their main source are plants bark, leaves, twigs, fruits, resins or oils. The biological activity of triterpens is very diversified and many studies have already confirmed the following therapeutic effects: anti-inflammatory, antimicrobial, antiviral, antifungial, immunomodulatory, and hepatoprotective. Synthesis of triterpenes derivates can be performed by chemical or enzymatic reactions, however biotransformation is more specific and eliminates the side products and the molecule alterations. These processes use isolated enzymes or microorganisms. Cell culture in vitro eliminates problems like extract variability as well as instability of the compounds being obtained during the extraction process. What is more, it ensures high reproducibility and optimal regio- and enantioselectivity. The most widely used technique is a classical screening of a series of microbial strains. Studies on triterpene biotransformation give a lot of information about new biologically active compounds and let predict the metabolism of biological compounds. This review presents most important advancements in the metabolic engineering of microorganisms for the production of triterpenoids. Moreover, the review highlights general strategies to obtain rich biochemical diversity of plants by employing the biocatalysts produced by microorganisms or tissue cultures.
Nanostructured lipid carriers (NLC) are stable colloidal formulations with notable advantages for drug delivery systems. Thanks to their physicochemical stability, biocompatibility, biodegradability and controlled drug release, they have received increasing attention for the last several years. The aim of the study was to prepare and characterize nanostructured lipid carriers (NLC). Both, the effect of the process parameters and the effect of the preemulsion composition on the NLC properties were investigated. In the work, different type of surfactants (i.e. decyl glucoside, Poloxamer188, Tween 80, sodium cholate) and their combinations were used to stabilize NLC dispersions. Moreover, several kinds of solid lipids (modified beeswax, gliceryl behenate, cetyl palmitate and berry wax) and liquid lipids (caprilic/capric triglyceride and decyl oleate) were applied. An ultrasonication method using a probe type sonicator was used to obtain NLC, and the time and energy of the process were modified throuhout. The physicochemical properties of the formulations, such as particle size, size distribution, polidispersity index were studied using the dynamic light scattering (DLS) method. The electrophoretic mobility of obtained particles was also measured, using the Zetasizer Nano ZS Malvern Instrument based on the Laser Doppler Velocimetry (LDV) technique. Knowing the value of electrophoretic mobility of particles for given conditions, the zeta potential was determined. The obtained results showed that the process parameters and the composition of the preemulsion had significant impact on the nanoparticles structure. The optimal formulations size ranged between 60 and 80 nm, and the value of their zeta potential was up to -30mV. The stability of these systems was further confirmed by macroscopic observation.
Celem pracy było opracowanie kompozycji do mycia zawierających jako składnik przeciwbakteryjny i sebostatyczny, ekstrakt z kory dębu pozyskany w warunkach nadkrytycznych CO2 (SC-CO2). Na podstawie opracowanych receptur otrzymano serię produktów zawierających w swoim składzie od 0,1% do 0,5% ekstraktu. Jako główne składniki myjące zastosowano łagodne związki powierzchniowo czynne (ZPCz): alkilopoliglukozydy, glutaminiany, glicyniany i sarkozyniany. Dla stabilnych produktów przeprowadzono badania właściwości fizykochemicznych i użytkowych, badano pH, napięcie powierzchniowe, lepkość, właściwości myjące i pianotwórcze. Dla wybranych produktów, za pomocą analizatora skóry AramoTS, przeprowadzono badania aparaturowe oceniające wpływ produktów na stan skóry. Analiza otrzymanych wyników wykazała, że ekstrakt SC-CO2 z kory dębu może znaleźć zastosowanie jako składnik aktywny w kompozycjach myjących przeznaczonych do pielęgnacji cery tłustej i trądzikowej. Otrzymano stabilne produkty do mycia, które dzięki zawartości ekstraktu z kory dębu wykazywały działanie zmniejszające tłustość skóry.
 The formation of oil/water (O/W) nano-emulsions suitable for cosmeceutical application was studied. Nano-emulsions were prepared by using phase inversion composition (PIC) method, one of the low-energy emulsification methods. The process consist of stepwise water addition to oil/surfactant mixture, at T = 25°C. Caprylic/capric triglycerides (GTCC), propylene glycol dicaprylate/dicaprate (PC) and oleic acid (OA) were applied as an oil phase. Polysorbate 80 was used as the surfactant. Kinetic stability of the nano-emulsions was analyzed by measuring droplet size as a function of time for different oil/surfactant ratio. The particles size distribution was analyzed by means DLS measurement technique (Dynamic Light Scattering), using Zetasizer Nano ZS (Malvern Instruments, UK). One of triterpenoic acid, practically non-water soluble substance was selected as an active and incorporated into the stable formulation. The obtained results proved that the nanoemulsion NE-T80-GTCC-20:80 based on caprylic/capric triglycerides with the oil/surfactant ratio O/S = 2 0:80 and the droplet size r = 25 nm was the most stable one and additionally showed the highest solubilisation capacity for the triterpene.
Classical methods of the extraction of active ingredients from the plant material are expensive, complicated and often environmentally unfriendly. The micelle-mediated extraction method (MME) seems to be a good alternative. In this work, extractions of elderberry blossoms (Flos Sambuci) were performed using MME methods. Several popular surfactants and whey protein concentrate (WPC) was applied in the process. The obtained results were compared with those obtained in extraction by means of water. Antioxidant properties of the extracts were analyzed by using two different methods: reaction with di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) reagent and Follin's method. Furthermore, the flavonoid content in the extracts was determined. The results confirmed that the MME method with using whey protein might be an alternative method for obtaining, rich in natural antioxidants, plant extracts.
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