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1.
A new alcohol oxidase-peroxidase method of determination of ethanol content in fermented musts and wine products is described and compared to conventional methods routinely used in winemaking. The sensitivity, accuracy, and reliability of this method were determined. The results of ethanol determination in fermented musts and wines correlated well with the data obtained by refractometry (correlation coefficient R = 0.9595, p < 0.0001) and densitometry (correlation coefficient R = 0.9384, p < 0.0001). This method is less time- and labor-consuming and allows simultaneous testing a series of wine samples.  相似文献   

2.
The effect of percent relative humidity (16–84% RH), moisture content (4.2–6.5% w/w MC), and compression force (4.9–44.1 kN CF) on the light-induced fluorescence (LIF) response of 10% w/w active pharmaceutical ingredient (API) compacts is reported. The fluorescent response was evaluated using two separate central composite designs of experiments. The effect of % RH and CF on the LIF signal was highly significant with an adjusted R 2 ?=?0.9436 and p?<?0.0001. Percent relative humidity (p?=?0.0022), CF (p?<?0.0001), and % RH2 (p?=?0.0237) were statistically significant factors affecting the LIF response. The effects of MC and CF on LIF response were also statistically significant with a p value <0.0001 and adjusted R 2 value of 0.9874. The LIF response was highly impacted by MC (p?<?0.0001), CF (p?<?0.0001), and MC2 (p?=?0022). At 10% w/w API, increased % RH, MC, and CF led to a nonlinear decrease in LIF response. The derived quadratic model equations explained more than 94% of the data. Awareness of these effects on LIF response is critical when implementing LIF as a process analytical tool.  相似文献   

3.
Ethyl carbamate (EC), a pluripotent carcinogen, is mainly formed by a spontaneous chemical reaction of ethanol with urea in wine. The arginine, one of the major amino acids in grape musts, is metabolized by arginase (encoded by CAR1) to ornithine and urea. To reduce the production of urea and EC, an arginase-deficient recombinant strain YZ22 (Δcarl/Δcarl) was constructed from a diploid wine yeast, WY1, by successive deletion of two CAR1 alleles to block the pathway of urea production. The RT-qPCR results indicated that the YZ22 almost did not express CAR1 gene and the specific arginase activity of strain YZ22 was 12.64 times lower than that of parent strain WY1. The fermentation results showed that the content of urea and EC in wine decreased by 77.89 and 73.78 %, respectively. Furthermore, EC was forming in a much lower speed with the lower urea during wine storage. Moreover, the two CAR1 allele deletion strain YZ22 was substantially equivalent to parental strain in terms of growth and fermentation characteristics. Our research also suggested that EC in wine originates mainly from urea that is produced by the arginine.  相似文献   

4.
Saccharomyces cerevisiae (SC) is the main driver of alcoholic fermentation, however for aroma and flavor formation in wine, non-Saccharomyces species can have a powerful effect. This study aimed to compare untargeted volatile compound profiles from SPME–GCxGC-TOF-MS and sensory analysis data of Sauvignon blanc wine inoculated with six different non-Saccharomyces yeasts followed by SC. Torulaspora delbrueckii (TD), Lachancea thermotolerans (LT), Pichia kluyveri (PK) and Metschnikowia pulcherrima (MP) where commercial starter strains, while Candida zemplinina (CZ) and Kazachstania aerobia (KA), were isolated from wine grape environments. Each wine showed a distinct profile both sensorially and chemically. SC and CZ wines were the most distinct in both of these cases. SC wine had guava, grapefruit, banana, and pineapple aromas while CZ wine was driven by fermented apple, dried peach/apricot, and stewed fruit as well as sour flavor. Chemically over 300 unique features were identified as significantly different across the fermentations. SC wine had the highest number of esters in the highest relative concentration but all the yeasts had distinct ester profiles. CZ wine displayed the highest number of terpenes in high concentration but also produced a large amount of acetic acid. KA wine was high in ethyl acetate. TD wine had fewer esters but three distinctly higher thiol compounds. LT wine showed a relatively high number of increased acetate esters and certain terpenes. PK wine had some off odor compounds while the MP wine had high levels of methyl butyl-, methyl propyl-, and phenethyl esters. Overall, this study gives a more detailed profile of these yeasts contribution to Sauvignon blanc wine than previously reported.  相似文献   

5.
Industrial ethanol fermentation is subject to bacterial contamination that causes significant economic losses in ethanol fuel plants. Chronic contamination has been associated with biofilms that are normally more resistant to antimicrobials and cleaning efforts than planktonic cells. In this study, contaminant species of Lactobacillus isolated from biofilms (source of sessile cells) and wine (source of planktonic cells) from industrial and pilot-scale fermentations were compared regarding their ability to form biofilms and their sensitivity to different antimicrobials. Fifty lactobacilli were isolated and the most abundant species were Lactobacillus casei, Lactobacillus fermentum and Lactobacillus plantarum. The majority of the isolates (87.8%) were able to produce biofilms in pure culture. The capability to form biofilms and sensitivity to virginiamycin, monensin and beta-acids from hops, showed inter- and intra-specific variability. In the pilot-scale fermentation, Lactobacillus brevis, L. casei and the majority of L. plantarum isolates were less sensitive to beta-acids than their counterparts from wine; L. brevis isolates from biofilms were also less sensitive to monensin when compared to the wine isolates. Biofilm formation and sensitivity to beta-acids showed a positive and negative correlation for L. casei and L. plantarum, respectively.  相似文献   

6.
Larvae of Galleria mellonella are widely used for evaluating the virulence of microbial pathogens and for measuring the efficacy of anti-microbial agents and produce results comparable to those that can be obtained using mammals. In this work, the suitability of using G. mellonella larvae to measure the relative toxicity of a variety of food preservatives was evaluated. The response of larvae to eight commonly used food preservatives (potassium nitrate, potassium nitrite, potassium sorbate, sodium benzoate, sodium nitrate, sodium chloride, sodium nitrite and sodium acetate) administered by feeding or by intra-haemocoel injection was measured. A significant correlation between the LD50 (R 2?=?0.8766, p?=?0.0006) and LD80 (R 2?=?0.7629, p?=?0.0046) values obtained due to oral or intra-haemocoel administration of compounds was established. The response of HEp-2 cells to the food preservatives was determined, and a significant correlation (R 2?=?0.7217, p?=?0.0076) between the LD50 values of the compounds administered by feeding in larvae with the IC50 values of the compounds in HEp-2 cells was established. A strong correlation between the LD50 values of the eight food preservatives in G. mellonella larvae and rats (R 2?=?0.6506, p?=?0.0156) was demonstrated. The results presented here indicate that G. mellonella larvae may be used as a model to evaluate the relative toxicity of food preservatives, and the results show a strong positive correlation to those obtained using established cell culture and mammalian models.  相似文献   

7.

Background

Pancreatic cancer (PC) has poorer prognosis and higher surgical invasiveness than many other cancers, with associated psychiatric symptoms including depression and anxiety. Perioperative depression has not been investigated in PC patients regarding surgical stress and relevant interventions.

Methods

We evaluated chronological depressive changes and subjective physical symptoms in surgically treated PC patients preoperatively and at 3 and 6 months postoperatively.Enrolled patients undergoing pancreatic tumor surgery completed questionnaires based on the Self-Rating Depression Scale (SDS) and Functional Assessment of Cancer Therapy for Patients with Hepatobiliary Cancer (FACT-Hep) preoperatively, and at 3 and 6 months postoperatively. Responses were analyzed with JMP® Pro using one-way and two-way ANOVA, Spearman’s rank correlation coefficient, and multiple regression analysis.

Results

Malignancy was diagnosed in 73 of 101 patients postoperatively; SDS score was significantly higher in these patients than in those with benign tumors at all timepoints: malignant/benign, 41.8/37.9 preoperatively (p?=?0.004); 43.5/37.8 3 months postoperatively (p?=?0.006); and 42.9/37.7 6 months postoperatively (p?=?0.020). SDS scores were significantly higher in patients <?65 years old with malignancy at 3 months than at 6 months postoperatively (44.6/42.5, p?=?0.046) and in patients with malignancy who underwent pancreaticoduodenectomy at 3 months postoperatively than preoperatively (43.4/41.1; p?=?0.028). SDS scores moderately correlated with 8 physical symptom-related FACT-Hep items 3 months postoperatively (p?<?0.05), showing low-to-moderate correlation with 16 physical symptom-related FACT-Hep items at 6 months postoperatively (p?<?0.05). Multiple regression analysis of FACT-Hep symptoms significantly correlated with SDS scores revealed the following significant variables: “lack of energy” (p?<?0.000) and “pain” (p?=?0.018) preoperatively (R2?=?0.43); “able to perform usual activities” (p?=?0.031) and “lack of energy” (p?<?0.000) at 3 months postoperatively (R2?=?0.51); and “stomach swelling or cramps” (p?=?0.034) and “bowel control” (p?=?0.049) at 6 months postoperatively (R2?=?0.52).

Conclusions

PC patients experience persistently high levels of depression preoperatively through 6 months postoperatively, with associated subjective symptoms including pain and gastrointestinal symptoms.

Trial registration

UMIN Clinical Trials Registry 000009592, Registered 20 December 2012.
  相似文献   

8.
Spray-dried ipratropium bromide (IPB) microspheres for oral inhalation were engineered using Quality by Design. The interrogation of material properties, process parameters, and critical product quality attributes interplay enabled rational product design. A 27–3 screening design exhibited the Maillard reaction between L-leucine (LL) and lactose at studied outlet temperatures (OT) >130°C. A response surface custom design was used in conjunction with multicriteria optimization to determine the operating design space to achieve inhalable microparticles. Statistically significant predictive models were developed for volume median diameter (p?=?0.0001, adjusted R 2? =?0.9938), span (p?=?0.0278, adjusted R 2? =?0.7912), yield (p?=?0.0020, adjusted R 2? =?0.9320), and OT (p?=?0.0082, adjusted R 2? =?0.8768). An independent verification batch confirmed the model’s predictive capability. The prediction and actual values were in good agreement. Particle size and span were 3.32?±?0.09 μm and 1.71?±?0.18, which were 4.7 and 5.3% higher than the predicted values. The process yield was 50.3%, compared to the predicted value of 65.3%. The OT was 100°C versus the predicted value of 105°C. The label strength of IPB microparticles was 99.0 to 105.9% w/w suggesting that enrichment occurred during the spray-drying process. The present study can be utilized to initiate the design of the first commercial IPB dry powder inhaler.  相似文献   

9.
10.
A comparative estimation was conducted to assess the prevalence of genotypes and alleles of the R>Q(353) polymorphism of the coagulation factor FVII gene between a group of the Russian adolescents with essential arterial hypertension and a group of Russian adolescents without such health problems. The RR genotype was diagnosed in 55 adolescents (75.34%) of the control group and in 99 adolescents (84.61%) of the adolescents suffering from essential arterial hypertension (χ2 = 1.949, p = 0.163). The R allele frequency was, respectively, 85.62 and 91.88% (χ2 = 3.110, p = 0.078). The role of the FVII gene in the determination of the F7 plasma activity was defined in adolescents with essential arterial hypertension and holders of different alleles. Holders of the R allele had significantly higher activity of coagulation factor F7 (97.66 ± 15.48 against 83.37 ± 15.16, p = 0.002), factor F2 (107.45 ± 6.03 against 103.75 ± 6.81, p = 0.023), and antithrombin III (104.47 ± 15.54% against 95.87 ± 11.30%, p = 0.024). than holders of the Q allele. This relationship was not found in adolescents of the control group.  相似文献   

11.
12.
Yeast cryotolerance may be advantageous for cider making, where low temperatures are usually employed. Here, we crossed the cryotolerant S. eubayanus with a S. cerevisiae wine strain and assessed the suitability of the hybrids for low-temperature cider fermentation. All strains fermented the juice to 5% ABV, but at different rates; hybrid strains outperformed S. cerevisiae, which was sensitive to low temperatures. The best hybrid fermented similarly to S. eubayanus. S. eubayanus produced sulphurous off flavours which masked a high concentration of fruity ester notes. This phenotype was absent in the hybrid strains, resulting in distinctly fruitier ciders. Aroma was assessed by an independent consumer panel, which rated the hybrid ciders as identical to the wine strain cider. Both were significantly more pleasant than the S. eubayanus cider. Interspecific hybridization can apparently be used effectively to improve low-temperature fermentation performance without compromising product quality.  相似文献   

13.
Numbers, dynamics of distribution for ten years, and relations between density and the rate of urbanization in nine species of Turdidae are calculated. During the last ten years the area of spatial distribution of most species increased by 2–15 times. A positive relationship between the numbers of birds and the rate of urbanization is revealed in the Redstart (RN 142 = 0.16; p = 0.049) and the Black Redstart (RN 134 = 0.25; p = 0.03), a negative relationship was observed in the Nightingale (RN 134 = ?0.23; p = 0.006) and the Robin (RN 43 = ?0.28; p = 0.06). The numbers of Whinchat, Wheatear, and thrushes does not depend on the rate of urbanization.  相似文献   

14.

Objectives

To prepare (R)-phenyl-1,2-ethanediol ((R)-PED) with high enantiomeric excess (ee p) and yield from racemic styrene oxide (rac-SO) at high concentration by bi-enzymatic catalysis.

Results

The bi-enzymatic catalysis was designed for enantioconvergent hydrolysis of rac-SO by a pair of novel epoxide hydrolases (EHs), a Vigna radiata EH3 (VrEH3) and a variant (AuEH2A250I) of Aspergillus usamii EH2. The simultaneous addition mode of VrEH3 and AuEH2A250I, exhibiting the highest average turnover frequency (aTOF) of 0.12 g h?1 g?1, was selected, by which rac-SO (10 mM) was converted into (R)-PED with 92.6% ee p and 96.3% yield. Under the optimized reaction conditions: dry weight ratio 14:1 of VrEH3-expressing E. coli/vreh3 to AuEH2A250I-expressing E. coli/Aueh2 A250I and reaction at 20 °C, rac-SO (10 mM) was completely hydrolyzed in 2.3 h, affording (R)-PED with 98% ee p. At the weight ratio 0.8:1 of rac-SO to two mixed dry cells, (R)-PED with 97.4% ee p and 98.7% yield was produced from 200 mM (24 mg/ml) rac-SO in 10.5 h.

Conclusions

Enantioconvergent hydrolysis of rac-SO at high concentration catalyzed by both VrEH3 and AuEH2A250I is an effective method for preparing (R)-PED with high ee p and yield.
  相似文献   

15.

Background

The present study aimed to develop an automated computed tomography (CT) score based on the CT quantification of high-attenuating lung structures, in order to provide a quantitative assessment of lung structural abnormalities in patients with Primary Ciliary Dyskinesia (PCD).

Methods

Adult (≥18?years) PCD patients who underwent both chest CT and spirometry within a 6-month period were retrospectively included. Commercially available lung segmentation software was used to isolate the lungs from the mediastinum and chest wall and obtain histograms of lung density. CT-density scores were calculated using fixed and adapted thresholds based on various combinations of histogram characteristics, such as mean lung density (MLD), skewness, and standard deviation (SD). Additionally, visual scoring using the Bhalla score was performed by 2 independent radiologists. Correlations between CT scores, forced expiratory volume in 1?s (FEV1) and forced vital capacity (FVC) were evaluated.

Results

Sixty-two adult patients with PCD were included. Of all histogram characteristics, those showing good positive or negative correlations to both FEV1 and FVC were SD (R?=???0.63 and???0.67; p?<?0.001) and Skewness (R?=?0.67 and 0.67; p?<?0.001). Among all evaluated thresholds, the CT-density score based on MLD?+?1SD provided the best negative correlation with both FEV1 (R?=???0.68; p?<?0.001) and FVC (R?=???0.71; p?<?0.001), close to the correlations of the visual score (R?=???0.60; p?<?0.001 for FEV1 and R?=???0.62; p?<?0.001, for FVC).

Conclusions

Automated CT scoring of lung structural abnormalities lung in primary ciliary dyskinesia is feasible and may prove useful for evaluation of disease severity in the clinic and in clinical trials.
  相似文献   

16.
Endotoxins are components of Gram-negative bacteria with inherently high pro-inflammatory potential. In an urban environment, airborne endotoxins may associate with pollutants such as particulate matter, increasing the severity of the immune response by acting as a natural adjuvant to augment inflammatory respiratory disease development. Here, we present a closer look at outdoor urban endotoxins by applying a microbial-targeted collection strategy. Results from 87 samples distributed throughout the city of Antwerp ranged from 0.45 to 93.71 EU/m3, with a geometric mean of 4.49 EU/m3 and 95% confidence interval of 3.53–5.71 EU/m3. Sample collection was also coupled with the use of a Coulter counter, for which the particle count (2.5–10 μm/m3) showed a significant correlation with endotoxin concentration (R2?=?0.24; p?<?0.0001; n?=?64). In addition, the analysis of the cultivable bacterial colony-forming units on Reasoner’s 2A agar (expressed CFU/m3) showed to be a good indicator for airborne endotoxins (R2?=?0.57; p?<?0.0001; n?=?58). Moreover, identification of dominant bacterial colonies on these culture plates gave some indications on potential sources of these urban outdoor bacteria and endotoxins.  相似文献   

17.
Length-weight and length-length relationships are presented for two fish species collected during May 2015 to August 2016 from Narora site of the river Ganga. The parameters a and b of the length-weight relationships were estimated after the logarithmic transformation of the equation: W = aL b . The lengthlength relationships were also estimated using linear regressions. The coefficients of determination (R 2) values were >0.9 for both target fish species and linear regressions were highly significant (p < 0.001). Length-weight relationship indicated positive allometric growth pattern for Cirrhinus mrigala and negative allometric growth pattern for Xenentodon cancila. Length-length relationships for the selected fish species were also highly significant (R 2 > 0.9, p < 0.001).  相似文献   

18.
The genetic structure of susceptibility to type 1 diabetes (T1D) in the population of Tomsk was studied. We had a group of T1D patients (N = 285) and a population sample (N = 300) and we studied 58 SNPs localized in the 47 genes which products are involved in various metabolic pathways and processes as fibrogenesis, endothelial dysfunction, and inflammation. Genotyping was performed by mass spectrometry using the Sequenom MassARRAY system (United States). We compared the group of T1D patients and the population sample and found an association with the predisposition to disease for seven markers: rs3765124 of the ADAMDEC1 gene, genotype AA (p = 0.004), allele A (p = 0.033); rs1007856 of the ITGB5 gene, genotype TT (p = 0.015), allele T (p = 0.036); rs20579 of the LIG1 gene, genotype CC (p = 0.004), allele C (p = 0.002); rs12980602 of the IFNL2 gene, allele C (p = 0.029); rs4986819 of the PARP4 gene, allele C (p = 0.044); rs1143674 of the ITGA4 gene genotype GG (p = 0.002); rs679620 of the MMP3 gene, genotype AA (p = 0.008). Thus, the products of genes associated with T1D belong to different molecular classes: metalloproteases (ADAMDEC1, MMP3), cytokines (IL28A), cell surface receptors (ITGA4), adhesion molecules (ITGB5), DNA ligases (LIG1), and ribosyltransferase enzymes (PARP4). The ADAMDEC1, ITGA4, and ITGB5 genes belong to two biological processes: cell communication and signal transduction. The LIG1 and PARP4 genes regulate the metabolism of nucleic acids, MMP3 is involved in the regulation of protein metabolism, and the IFNL2 is involved in the immune response.  相似文献   

19.

Background

The muscle Ras (MRAS) gene resides on chromosome 3q22.3 and encodes a member of the membrane-associated Ras small GTPase proteins, which function as signal transducers in multiple processes including cell growth and differentiation. Its role in cardiovascular disease is not fully understood yet. In a preliminary study in heterozygous familial hypercholesterolaemia, we identified a locus linking the early onset of coronary artery disease (CAD) to chromosome 3q.22 and elected to sequence the MRAS gene using the MegaBACE DNA analysis system. In the present study, we investigated the association of seven single-nucleotide polymorphisms (SNPs) at this locus with CAD and its dyslipidaemia-related risk traits in 4,650 Saudi angiographed individuals using TaqMan assays by the Applied Biosystems real-time Prism 7900HT Sequence Detection System.

Results

Among the studied SNPs, rs6782181 (p = 0.017) and rs9818870T (p = 0.009) were associated with CAD following adjustment for sex, age and other confounding risk factors. The rs6782181_GG also conferred risk for obesity (1,764 cases vs. 2,586 controls) [1.16(1.03–1.30); p = 0.017], hypercholesterolaemia (1,686 vs. 2,744) [1.23(1.02–1.47); p = 0.019], hypertriglyceridaemia (1,155 vs. 3,496) [1.29(1.01–1.45); p = 0.043] and low high-density lipoprotein-cholesterol (lHDL-chol) levels (1,935 vs. 2,401) [1.15(1.02–1.30); p = 0.023] after adjustment. Additionally, rs253662_(CT+TT) [1.16(1.01–1.32); p = 0.030] was associated with lHDL-chol levels. Interestingly, rs253662 (p = 0.014) and rs6782181 (p = 0.019) were protective against acquiring high low-density lipoprotein-cholesterol (hLDL-chol) levels (p = 0.014), while rs1720819 showed similar effects against CAD (p < 0.0001). More importantly, a 7-mer haplotype, ACCTGAC (χ2 = 7.66; p = 0.0056), constructed from the studied SNPs, its 6-mer derivative CCTGAC (χ2 = 6.90; p = 0.0086) and several other shorter derivatives conferred risk for obesity. hLDL-chol was weakly linked to CTAA (χ2 = 3.79; p = 0.052) and CCT (χ2 = 4.32; p = 0.038), while several other haplotypes were protective against both obesity and hLDL-chol level.

Conclusion

Our results demonstrate that the genomic locus for the MRAS gene confers risk for CAD, obesity and dyslipidaemia and point to the possible involvement of other genes or regulatory elements at this locus, rather than changes in the M-Ras protein function, in these events.
  相似文献   

20.

Objectives

To develop a xylose-nonutilizing Escherichia coli strain for ethanol production and xylose recovery.

Results

Xylose-nonutilizing E. coli CICIM B0013-2012 was successfully constructed from E. coli B0013-1030 (pta-ack, ldhA, pflB, xylH) by deletion of frdA, xylA and xylE. It exhibited robust growth on plates containing glucose, arabinose or galactose, but failed to grow on xylose. The ethanol synthesis pathway was then introduced into B0013-2012 to create an ethanologenic strain B0013-2012PA. In shaking flask fermentation, B0013-2012PA fermented glucose to ethanol with the yield of 48.4 g/100 g sugar while xylose remained in the broth. In a 7-l bioreactor, B0013-2012PA fermented glucose, galactose and arabinose in the simulated corncob hydrolysate to 53.4 g/l ethanol with the yield of 48.9 g/100 g sugars and left 69.6 g/l xylose in the broth, representing 98.6% of the total xylose in the simulated corncob hydrolysate.

Conclusions

By using newly constructed strain B0013-2012PA, we successfully developed an efficient bioprocess for ethanol production and xylose recovery from the simulated corncob hydrolysate.
  相似文献   

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