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Polystyrene is considered stable to biological degradation. Lantinus tigrinus isolated from wood sample produced esterase in growth medium under normal conditions. However, acidic medium, 37°C temperature, presence of tween 80; and urea and yeast extract in mineral salt medium enhance the production of esterase and specific activity. Purified esterase was active at broad pH range and 45°C. FTIR analysis confirmed that esterase produced by Lantinus tigrinus effectively degraded polystyrene film and broke macromolecules down to non-toxic molecules. This study concludes that the presence of Lantinus tigrinus at dumping sites can be exploited for waste management containing high molecular weight synthetic polymers.
Proteins recognizing DNA damaged by the chemical carcinogen N- acetoxy-acetylaminofluorene (AAAF) were analyzed in nuclear extracts from rat tissues, using a 36 bp oligonucleotide as the substrate and an electrophoretic mobility shift assay. Two major proteins that form complexes with DNA damaged by AAAF were detected; one of them also bound DNA damaged by cis-diammine-dichloroplatinum. The complex specific for AAAF-damaged DNA contained protein loosely attached to nuclear components. It was extracted with 0.1 M NaCl. The amount of this protein was estimated at about 105 copies per liver cell nucleus, and its probable size was about 42 kDa as detected by the Southwestern blotting assay. Its affinity for DNA damaged by AAAF was ~10-fold higher than that for undamaged DNA. Analogous AAAF- DDB (damaged-DNA-binding) proteins were also detected in extracts from rat brain, testis and kidney tissue. The levels of such proteins were not affected in rats treated with the carcinogen 2-acetylaminofluorene.
Amaranth seeds and their main product amaranth oil are a rich source of bioactive substances. The non-saponifi able substances which accompany lipids include: squalene, tocopherols, sterols and others. The aim of the study was to compare the content of squalene, tocopherols and phytosterols in amaranth oils obtained by various techniques. The oil was extracted from seeds (Amaranthus cruentus) with the use of supercritical fl uid extraction (SFE), extraction with a chloroform/methanol mixture and expeller pressing. Contents of squalene and tocopherols were determined with high performance liquid chromatography (HPLC) method. The content of sterols in oils was determined by gas chromatography coupled with mass spectrometry (GC-MS). The highest squalene content was found for the oil obtained as a result of supercritical CO2 extraction (6.95 g/100 g of oil). A lower content of squalene was noted in the oil extracted with organic solvents and in cold-pressed oil – 6.00 and 5.74 g/100 g of oil, respectively. The amaranth oils were characterised by a signifi cant content of tocopherols. The oil obtained as a result of fl uid extraction was characterised by the highest content of tocopherols (131.7 mg/100 g of oil). A dominating homologue (40%) was β-tocopherol. Also the same sample was characterised by the highest content of sterols (2.49 g/100 g of oil). In all samples the predominating sterol was sum of α-spinasterol and sitosterol, which accounted for 45%, 56% and 53% of total analysed sterols for the oil obtained from SFE, from extraction with solvents and from cold pressing, respectively.
This review article demonstrates fundamentals regarding the manufacturing of multilayer oil-in-water (M-O/W) emulsions and factors affecting stability of these systems. Moreover, characteristics of major bioactive lipophilic components and ingredients mostly applied to form multilayered membranes as well analytical methods used to examine properties of M-O/W emulsions are specified. It has been shown that production of M-O/W systems is based on the layer-by-layer (LbL) electrostatic deposition technique which makes use of the electrostatic attraction of oppositely charged surfactants and biopolymers to form multicomposite protective layers around emulsion droplets. Finally, limitations regarding studies of M-O/W systems which should be developed are specified
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The paper presents the results of studies on the production and quality assessment of mycelia of three varieties of King Bolete: Boletus edulisvar. pinicolusVitt. Boletus edulisvar. piceicolusVasilkov and Boletus edulisvar. reticulatus (Schaeff. ex Boud.) Bat. In the biomass of mycelium for food the following physicochemical parameters were determined: contents of dry matter, soluble protein – albumins, globulins and prolamins, the rehydratation rate, sensory and microbial quality was assessed.
Lactobacillus plantarum SKT109 was isolated and identified from Tibet Kefir, and the exopolysaccharride (EPS)-producing properties of the strain were evaluated. Growth of strain SKT109 in a semi-defined medium at 37°C increased the viscosity of the medium, corresponding to production of an EPS (58.66 mg/L). The EPS was isolated and purified, and it was shown to consist of fructose and glucose in an approximate molar ratio of 3:1, with an average molecular weight of 2.1x106 Da. The aqueous solution of EPS at 1% (w/v) exhibited shear thinning behavior. Microstructural studies of the EPS demonstrated a highly compact structure with a smooth surface, facilitating formation of film by the polymer; the EPS was composed of many different sizes of spherical lumps with tendency to form molecular aggregates. Studies on the milk fermentation characteristics of L. plantarum SKT109 showed that the strain survived well in fermented milk with counts about 8.0 log cfu/g during 21 days of storage at 4°C. The use of the EPS-producing strain improved the rheology of the fermented milk without causing post-acidification during storage. Particularly, L. plantarum SKT109 improved the fermented milk flavor by increasing the concentration of characteristic flavor compounds and eliminating those with disgusting flavors. The results of the present study indicated that EPS-producing L. plantarum SKT109 could serve as a promising candidate for further exploitation in fermented foods.
Bacillus thuringiensis is a Gram-positive, aerobic, facultative anaerobic and endosporeforming bacterium. Different strains of this species have the ability to produce parasporal crystalline inclusions which are toxic to larvae of different insect orders and other invertebrates and cause rapid death of the host. To determine the importance of this species in microbial control, we collected native strains and studied their virulence on the diamondback moth, Plutella xylostella. More than 148 samples were collected from Alborz, Guilan and Mazandaran Provinces. Experimental samples, including soil samples from forests, fruit gardens, agricultural fields, diseased and dead larvae, were transferred to a laboratory in sterile plastic containers. For evaluating B. thuringiensis isolates virulence, a cabbage leaf dip method with 106 cell ⋅ ml–1 concentration of various Bt isolates was applied to diamondback moths. Larval mortality was recorded 72 h after treatment. Based on bioassay results, all isolates were classified into three high, medium and low virulence groups. Protein level characterization based on the SDS-PAGE gel analysis showed that two isolates from a high virulence group have proteins of high molecular masses of 121 and 109 kDa. Results revealed that there is a positive correlation between protein masses and virulence of isolates. In addition, this research introduced nine strains that are highly toxic to P. xylostella and would be valuable as insecticidal agents for controlling lepidopteran pests.
Рассматриваются результаты исследований химического состава и yстойчивости к плеснению сырья применяемого в производстве плетеной мебели. Полученные результаты показывают, что специфические термопластические свойства ротанга связаны с высоким содержанием лингина и пентозанов. Его же высокая устойчивость к плеснению связана с выcокими количествами минеральных веществ во внешних и внутренних слоях стеблей. Небольшая устойчивость ивы к плеснению связана с нарушением биоструктуры древесины в ходе гидротермической обработки.
This study investigated the solid waste characterization of the city of Kocaeli. With this aim solid waste groups were analyzed for sub-municipalities of the city. Representative sampling points were determined in municipalities with populations over 5,000. Four different socio-economic groups (the downtown district plus low, intermediate, and high income levels) were investigated in the study. Characterization studies were performed for a 2-year period. In this context, 16 and 13 different solid waste species were categorized for winter and summer seasons, respectively. The results of the study showed that kitchen wastes constitute the highest proportion for all socio-economic groups despite dissimilarities in waste distribution of municipalities. It was followed by combustible wastes and plastic wastes. Reducing waste components into five groups as organic wastes, recycled wastes, hazardous wastes, combustible wastes and others, an increase was seen in amounts of recycled, hazardous, and combustible wastes in winter season, whereas the amount of organic wastes decreased. Investigating general waste distribution for different income levels without any seasonal distinction, it was observed that highest values of organic and recycled wastes were seen in the downtown district and high-income groups, whereas combustible, hazardous, and other wastes were higher in low-income groups. In general, as a result of the characterization study without any seasonal and/or economical distinctions, proportions of organic, recycled, combustible, hazardous wastes, and others were determined as 41.53%, 30.51%, 20.64%, 2.12%, and 5.20%, respectively.
A β-mannosidase was purified from Phlebia radiata grown in a medium containing wheat bran or galactomannan as a carbon source. Maximal activity was observed at pH 5.5 and at 50°C. Highly purified isoforms of β-mannosidase (GM-1, GM-2) isolated from media containing galactomanan and (OT-1) media with wheat bran were obtained by means of column chromatography on Q-Sepharose, SP-Sepharose and chromatofocusing on Polybuffer Exchanger PBE-94.
W pracy przedstawiono charakterystykę mokradeł mezoregionu Równiny Sępopolskiej, opracowaną na podstawie 46 dokumentacji złóż torfowych i gytiowisk oraz prac własnych. Na badanym obszarze stwierdzono 465 torfowisk i 10 gytiowisk o łącznej powierzchni 6008 ha. Torfowiska tworzyły się w obniżeniach wytopiskowych przy spływowym typie zasilania hydrologicznego. Wskaźnik zatorfienia mezoregionu wynosi 5.1% i jest zbliżony do przeciętnego w kraju, a niższy w stosunku do Poj. Mazurskiego. Dominują głębokie torfowiska niskie, o małej powierzchni z przewagą silnie rozłożonych torfów olesowych. Podano zasady użytkowania i ochrony mokradeł z uwzględnieniem uwarunkowań siedliskowych Równiny Sępopolskiej.
W pracy przedstawiono charakterystykę obszarów mokradłowych Pojezierza Ełckiego na podstawie 122 dokumentacji geologicznych oraz prac własnych. Opracowano mapę ich rozmieszczenia. Stwierdzono 1999 torfowisk i 20 gytiowisk o łącznej powierzchni 21 324.9 ha. Przeważają obiekty małe do 5 ha. Dominują torfowiska niskie, głębokie o przewadze torfów olesowych. Ponad 87% ich areału znajduje się w fazie decesji. Przedstawione w pracy syntetyczne informacje mogą służyć do ustalania zasad gospodarowania i ochrony mokradeł.
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