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EN
The utilization of two side streams from the Cyklopol process was studied. The first one is the monohydric alcohols fraction and the second one is the fraction of mono-carboxylic acids. We propose to utilize these fractions and their esters as a component of gel formulation painting remover. Our composites have a gel formulation suitable for easy application on a vertical surface. D-DBS (1,3:2,4-Di-O-benzylidene-Dsorbitol) or MHPC (methylhydroxypropylcellulose) were used as gelling agents for organic liquids. The D-DBS compound is characterized by transparency and reduced yellowing of composition. The properties of the obtained preparations were compared to the properties of commercially available gel formulations SCANSOL and STRIPER. Our initial investigations indicate that side streams from the Cyklopol process are good and cheap resources of raw materials for the preparation of paint stripping formulations.
EN
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.
EN
In this work the La2O3/CeO2 (33 mol % of La) and CaO/CeO2 (33 mol % of Ca) catalysts were prepared by the impregnation method and characterized by XRD and CO2-TPD. The catalytic properties of the catalysts were tested in the OCM process at 1073 K using the methane/oxygen mixture of the mole ratio 3.7 or 2.5 additionally containing CO2 and helium balance. It was found that in the presence of both catalysts an addition of CO2 enhances the selectivity to the ethylene and ethane and it does not have any negative influence on methane conversion. In the case of the CaO/CeO2 catalyst the promoting effect of CO2 was the highest. When the partial pressure of CO2 equals to 39 kPa the increase in selectivity from 36 to 41% was noted while the conversion of methane equal to 19.4-19.7 %.
EN
The aim of this work was preparation and characterization of o/w nano and microemulsions containing Crodamol PC® as the oil phase. An influence of surfactants system applied in formulations on the properties of the obtained emulsions has been studied. The emulsions were prepared by phase inversion composition method. The measurement of the internal phase droplet size and the study of rheological properties were done. The obtained results showed that the prepared transparent emulsion systems are nano and microemulsion formulation. Moreover, it was concluded that the microemulsions stability and the size of the internal phase droplets depended on the type and the concentration of emulsifier and on the ratio of water phase to oil. Rheological studies have confirmed that the obtained microemulsions showed pseudoplastic behaviour.
5
100%
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2013
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vol. 60
|
issue 4
731-735
EN
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.
EN
The formulations of washing cosmetics i.e. shower gels, containing extracts obtained during supercritical CO2 extraction process as active ingredient, were developed. The subject of the study was the analysis of the physicochemical and user properties of the obtained products. In the work supercritical CO2 extracts of black currant seeds, strawberry seeds, hop cones and mint leafs were used. The formulation contains a mixture of surfactants (disodium cocoamphodiacetate, disodium laureth sulfosuccinate, cocoamide DEA, cocoamidepropyl betaine, Sodium Laureth Sulfate). Various thickener agents were applied to the obtained desired rheological properties of the cosmetics. Among others, sorbitol acetal derivatives, methylhydroxypropylcellulose and C10-30 alkyl acrylate crosspolymer were used. For stable products, the effect of extracts addition (black currants seeds, strawberries seeds, mint and hops, obtained from supercritical CO2 extraction process) on the cosmetics properties, such as pH, viscosity, detergency and foam ability, were determined. The obtained results showed that the extracts could be used as components of shower gels.
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2013
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vol. 60
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issue 4
779-782
EN
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.
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2015
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vol. 62
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issue 2
229-233
EN
Nano- and microemulsions containing as the oil phase caprylic/capric propylene glycol diesters (Crodamol PC) were investigated as potential vehicle for controlled release of geranic acid. The influence of emulsifiers and co-surfactants on stability of the emulsions was investigated. Different kind of polysorbates (ethoxylated esters of sorbitan and fatty acids) were applied as the emulsifiers. The short-chain alcohols (ethanol, 1-propanol, 1-butanol) were used as co-surfactants. The emulsions were prepared at ambient temperature (25°C), by the phase inversion composition method (PIC). The stable O/W high dispersed emulsion systems based on Crodamol PC, of mean droplets size less than 200 nm, were prepared. Microemulsions stabilized by the mixture of Polisorbat 80 and 1-butanol were characterized by the largest degree of dispersion (137 nm) and the lowest PDI value (0.094), at surfactant/co-surfactant: oil weight ratio 90:10. The stable nano-emulsion (mean droplet size of 33 nm) was obtained for surfactant: oil (S:O) weight ratio 90:10, without co-surfactant addition. This nano-emulsion was chosen to release studies. The obtained results showed that the prepared stable nano-emulsion can be used as a carrier for controlled release of geranic acid. The active substance release from the nano-emulsion and the oil solution, after 24 hours was 22%.
EN
Dehydrogenation of propane in the presence of CO2 was considered as an alternative to commercial dehydrogenation pathway of obtaining propene and the new sources of synthesis gas. Based on thermodynamic calculations and a catalytic tests it was shown that by controlling CO2 concentration in the feed the molar ratio of H2/CO (synthesis gas) in the products mixture can be regulated. Several different pathways of DHP-CO2 process integration with commercialized chemical processes utilized synthesis gas were proposed
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2013
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vol. 60
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issue 4
773-777
EN
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.
EN
In this paper, the extracts of three-part beggarticks (Bidens tripartita) were prepared using ultrasonic assisted micelle-mediated extraction method (UAMME). Different kind of surfactants and WPC (whey protein concentrate) were applied. In the B. tripartita extracts twenty polyphenols were identified by UPLC-DAD-MS. Both aqueous and UAMME extracts mainly contained chlorogenic acid, caftaric acid and its derivatives as well as luteolin 7-O-glucoside. The luteolin was extracted with Rokanol B2 and Triton X-100. Furthermore, antioxidative properties of the extracts were analyzed with two methods: reactions with di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (DPPH) reagent and Follin's method. The DPPH radical scavenging by micellar extracts was in general comparable with the antioxidant activity of conventional extracts. The most active was sample with Tego Care CG90, reducing about 73% of the radical. Obtained results confirmed that the UAMME might be an alternative method, to the liquid-liquid or solid-liquid extraction, of obtaining specified extracts rich in active compounds. Selecting a suitable surfactant may thus provide the expected composition of the extract.
EN
Nanostructured lipid carriers (NLC) composed of the substances generally recognized as safe (GRAS) were obtained by using a hot high-pressure homogenization technique (HPH). The influence of the number of homogenization cycles and concentration of a decyl glucoside surfactant on the NLC properties were studied. The system's stability was assessed by macroscopic observation, light backscattering and zeta potential measurements. NLC particle size was measured using dynamic light scattering (DLS). The kinetically stable formulations were loaded with forskolin and selected for in vitro drug permeation study using the Franz cell method. Concentration of forskolin in the receptor solution (i.e. ethanol/PBS mixture) was analyzed with high performance liquid chromatography (HPLC) with UV detection. The obtained results have shown that NLC formulations could be used as effective carriers for forskolin permeation through the skin.
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