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71.
The influence of fatty acids (free and bound as ethyl esters) on wine foaming was studied in different white wines and the corresponding sparkling wines. Moreover, from three of these wines the foam formed by CO(2) injection was separated, and two fractions were then obtained: foam wine (FW) and remainder wine (RW). In these fractions and the sparkling wines produced from them, foam properties and fatty acids were also determined. The free fatty acids C8, C10, and C12 were negatively correlated with foamability (HM), whereas the ethyl esters of hexanoic, octanoic, and decanoic acids were positively related to HM. The value of HM was directly proportional to the ratio of esterified to unesterified fatty acids. This was confirmed by the changes that occur in the esterification ratio during the second fermentation and aging. No influence was observed on either the Bikerman coefficient or the stability time of foam.  相似文献   
72.
The capability of environmental microorganisms to biodegrade simazine—an active substance of 2-chloro-s-triazine herbicides (pesticide waste since 2007)—was assessed. An enormous metabolic potential of microorganisms impels to explore the possibilities of using them as an alternative way for thermal and chemical methods of utilization. First, the biotope rich in microorganisms resistant to simazine was examined. Only the higher dose of simazine (100 mg/l) had an actual influence on quantity of bacteria and environmental fungi incubated on substrate with simazine. Most simazine-resistant bacteria populated activated sludge and biohumus (vermicompost); the biggest strain of resistant fungi was found in floral soil and risosphere soil of maize. Compost and biohumus were the sources of microorganisms which biodegraded simazine, though either of them was the dominant considering the quantity of simazine-resistant microorganisms. In both cases of periodic culture (microorganisms from biohumus and compost), nearly 100% of simazine (50 mg/l) was degraded (within 8 days). After the repeated enrichment culture with simazine, the rate of its degradation highly accelerated, and just after 24 h, the significant decrease of simazine (20% in compost and 80% in biohumus) was noted. Although a dozen attempts of isolating various strains responsible for biodegradation of simazine from compost and biohumus were performed, only the strain identified as Arthrobacter urefaciens (NC) was obtained, and it biodegraded simazine with almost 100% efficiency (within 4 days).  相似文献   
73.
Xanthohumol (XN) is the major prenylated chalcone of hops and hence an ingredient of beer. Despite many advances in understanding of the pharmacology of XN, one largely unresolved issue is its low bioavailability in the human organism. Also, not much is known about its actual concentrations and pharmacokinetics in liver and intestinal cells. Therefore, the uptake, intracellular distribution, and kinetics of XN were studied in various cell types, namely, hepatocellular carcinoma cells (HuH-7), hepatic stellate cells (HSC), primary cultured hepatocytes, and colorectal adenocarcinoma cells (Caco-2). Fluorescent microscopy allowed for the first time visualization and tracing of the uptake and intracellular distribution of XN. A rapid accumulation of XN concentrations that were up to >60-fold higher than the concentration present in the ambient culture medium was observed. Fluorescence recovery after photobleaching experiments revealed that most XN molecules are bound to cellular proteins, which may alter properties of cellular factors.  相似文献   
74.
This study investigates 11 agricultural management practices (AMPs) and their effects on seven visual soil quality indicators and soil aggregate stability. The survey carried out across eight pedoclimatic zones in Europe and China was based on visual soil assessments (New Zealand VSA method) performed on soils subject to different soil management practices and nearby similar soils, under similar farming features, without the distinctive soil management practice (control). Fisher's exact test was used to test if the management treatment was independent of the score of each visual soil quality indicator and to test if the management treatment produced a higher frequency of the score ‘good’. The results showed a statistically significant (α < .05) higher frequency of the score ‘good’ for ‘soil structure and consistency’ and/or ‘soil porosity’ for six AMPs. For no-till AMP, the null hypothesis can also be rejected for ‘susceptibility to erosion’ and ‘soil stability’ and for ‘mulching + permanent soil cover’ AMP, for the ‘presence of tillage pan’ and ‘soil colour’. The hypothesis that the management treatment was independent of the score of each indicator was rejected for ‘soil structure and consistency’ of three AMPs, for ‘soil porosity’ of three AMPs, for ‘soil colour’ of one AMP and for the ‘presence of tillage pan’ of one AMP. This study demonstrates that farming systems sharing a common influential soil management practice at different locations and with different soil types significantly affect the score of some visual soil quality indicators.  相似文献   
75.
An isolate of lead-ferritin obtained from soybean seeds sprouted in 25 mM of PbNO3 was introduced into the diet of both iron-deficient and iron non-deficient male rats. After a 21-day administration period, statistical differences in the lead accumulation in the femurs of the rats were noted. Iron-deficient rats accumulated more than four times the amount of lead in their bones than rats without iron-deficiency. No further decrease was observed in haemoglobin concentrations in the groups of animals fed with lead isolates, either iron-deficient or iron non-deficient. Also, no differences in the mean corpuscular haemoglobin (MCH) and mean corpuscular volume (MCV) were observed at the end of the experiment in the group of iron non-deficient rats fed with lead-ferritin isolate compared to the control group of iron non-deficient rats. In the iron-deficient group fed with lead-ferritin isolate, a small increase in haemoglobin concentrations, MCH, MCV and mean corpuscular haemoglobin concentrations (MCHC) was recorded. The results presented in this paper confirm that lead from the tested preparation—lead ferritin isolate—was better absorbed by those rats with induced iron deficiency anaemia. Additionally, we may also suspect based on the obtained results that absorption of ferritin-iron depends on iron status in the body.  相似文献   
76.
Particle size distribution (PSD) is a major soil characteristic, which is essential and commonly used for the development of pedotransfer functions (PTFs) to estimate the water retention of soils. The laser diffraction method (LDM) became a popular alternative to the standard sieve‐hydrometer method (SHM) of PSD measurement. Unfortunately, PSDs determined with LDM and SHM methods differ sometimes substantially. Moreover, it is claimed that the laser diffraction method underestimates finer fractions in favor of coarser fractions. Several authors have tried to elaborate on methods to recalculate LDM PSD into its SHM counterparts, but no universal methodology has been developed to this date. In this paper, we use PSD determined by LDM directly for PTF development and compare it with the classical PTF approach based on PSD measured by SHM. Four different PTF models based on LDM particle size distribution data were developed, with different PSD characteristics taken as the models' input variables. The possibility of using alternative PSD characteristics, such as deciles, area moment mean and volume moment mean, for PTF development was examined. The accuracy of PTF models constructed on the basis of LDM‐measured PSD was comparable with that of the developed models using texture data obtained from SHM, giving approximately the same RMSE and R2 values. Our study shows that LDM‐measured particle size distribution may be directly used for PTF developments without any recalculations to their sieve‐hydrometer counterparts.  相似文献   
77.
Based on data from the National Lynx Census, carried out in Poland in 2000-2001, and using Geographic Information System, we analysed nine habitat characteristics in 56 circular sample plots (113 km2 each), where lynx (Lynx lynx) have been recorded, and 118 plots with no signs of their presence. In plots with lynx the forest cover (on average 68%) was two times higher and the forest fragmentation lower than in plots with no lynx records. The plots with and without lynx differed significantly also in the number of villages and towns, length of main motorways and railways. Lynx occurrence was negatively associated to human settlements and transportation infrastructure. Logistic regression analysis showed that sufficient forest cover (>40%) and the short straight-line distance to the eastern or southern border of Poland (as a proxy of the distance to a more contiguous range of lynx in Europe) are the two most important variables explaining lynx distribution. We conclude that, in Poland, increase of forest fragmentation and transportation infrastructure may become important threats to lynx populations.  相似文献   
78.
Several oat brans (crunchy oat bran, oat bran alone, and oat breakfast cereal) and wheat brans (wheat bran alone, wheat bran powder, wheat bran with malt flavor, bran breakfast cereal, tablet of bran, and tablet of bran with cellulose) used as dietary fiber supplements by consumers were evaluated as alternative antioxidant sources (i) in the normal human consumer, preventing disease and promoting health, and (ii) in food processing, preserving oxidative alterations. Products containing wheat bran exhibited higher peroxyl radical scavenging effectiveness than those with oat bran. Wheat bran powder was the best hydroxyl radical (OH*) scavenger. In terms of hydrogen peroxide (H2O2) scavenging, wheat bran alone was the most effective, while crunchy oat bran, oat bran alone, and oat breakfast cereal did not scavenge H2O2. The shelf life of fats (obtained by the Rancimat method for butter) increased most in the presence of crunchy oat bran. When the antioxidant activity during 28 days of storage was measured by the linoleic acid assay, all of the oat and wheat bran samples analyzed showed very good antioxidant activities. The Trolox equivalent antioxidant capacity (TEAC) assay was used to provide a ranking order of antioxidant activity. The wheat bran results for TEAC (6 min), in decreasing order, were wheat bran powder > wheat bran with malt flavor > or = wheat bran alone > or = bran breakfast cereal > tablet of bran > tablet of bran with cellulose. The products made with oat bran showed lower TEAC values. In general, avenanthramide showed a higher antioxidant level than each of the following typical cereal components: ferulic acid, gentisic acid, p-hydroxybenzoic acid, protocatechuic acid, syringic acid, vanillic acid, vanillin, and phytic acid.  相似文献   
79.
80.
Diabetes is a disease characterized by a hyperglycemic stage that leads to a chronic inflammatory state. We evaluated the in vivo effect of a diet supplemented with 25 % cooked black bean cultivar Negro 8025 (N8025) flour in streptozotocin-induced diabetic rats. The effect was assessed before (preventive-treatment) and after (treatment) the onset of diabetes. There is a significant decrease of total phenolic, tannins and anthocyanins content after cooking, and the concentration of most of the single phenols analyzed are only slightly decreased. The treatment group showed a significant reduction of glucose (22.8 %), triglycerides (21.9 %), total cholesterol (29.9 %) and LDL (56.1 %) that correlates with a protection of pancreatic ß-cells. The diet with N8025 flour before the induction of diabetes did not exert a protective effect (glucose levels are similar to the diabetic control) but they have low levels of total cholesterol (47.5 %) and LDL (56.1 %). The preventive-treatment group did not inhibit the increase of TNF-α and IL-1β, whereas the treatment group did, compared to the diabetic control. Therefore, N8025 bean supplementation can be recommended to control diabetes.  相似文献   
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