beta-Fructofuranosidase

β - 果糖呋喃糖苷酶
  • 文章类型: Journal Article
    咖啡的采后发酵过程在过去的几年中迅速发展,由于对感官特性的质量和多样性的研究。一种新型的发酵,命名为自诱导厌氧发酵(SIAF),是一个被越来越多地使用的有前途的过程。本研究旨在评估SIAF期间咖啡饮料的感官改善以及微生物群落和酶活性的影响。SIAF过程在巴西农场进行长达8天。通过Q-graders评估咖啡的感官质量;通过16SrRNA和ITS区域的高通量测序鉴定微生物群落;以及酶活性(转化酶,多聚半乳糖醛酸酶,和内切-β-甘露聚糖酶)也进行了研究。SIAF在感官评估总分中增加了3.8分(与未发酵样品相比),除了呈现更多的风味多样性(特别是在果味和甜味描述符内)。高通量测序在三个过程中鉴定出655种细菌和296种真菌。细菌肠杆菌。,乳酸杆菌。,泛菌sp.,和真菌枝孢霉。和念珠菌sp。是主要的属。在整个过程中都发现了真菌毒素的潜在生产者,这表明存在污染的风险,因为其中一些在焙烧过程中没有降解。首次在咖啡发酵中描述了31种微生物。微生物群落受到进行该过程的地点的影响,主要与真菌的多样性有关。发酵前洗涤咖啡果实会导致pH值快速降低;乳酸菌的快速发展。和念珠菌的快速优势。;减少获得最佳感官评分所必需的发酵时间;种子中转化酶活性的增加;果壳中转化酶活性的表达性更高;咖啡果壳中聚半乳糖醛酸酶活性的下降趋势。内切-β-甘露聚糖酶活性的增加表明咖啡在该过程中开始发芽。SIAF具有提高咖啡质量和增加价值的巨大潜力,但是必须进行进一步的研究以获得其安全性。该研究可以更好地了解发酵过程中存在的自发微生物群落和酶。
    The postharvest fermentation process of coffee has rapidly advanced in the last few years due to the search for quality and diversity of sensorial profiles. A new type of fermentation, named self-induced-anaerobic fermentation (SIAF), is a promising process that has been increasingly used. This study aims to evaluate the sensorial improvement of coffee beverages during SIAF and the influence of microorganism\'s community and enzymatic activity. The SIAF process was conducted in Brazilian farms for up to 8 days. The sensorial quality of coffee was evaluated by Q-graders; the microbial community was identified by the high-throughput sequencing of 16S rRNA and ITS regions; and the enzymatic activity (invertase, polygalacturonase, and endo-β-mannanase) was also investigated. SIAF increased up to 3.8 points in the total score of sensorial evaluation (compared to the non-fermented sample), in addition to presenting more flavor diversity (especially within the fruity and sweetness descriptors). The high-throughput sequencing identified 655 bacterial and 296 fungal species during the three processes. The bacteria Enterobacter sp., Lactobacillus sp., Pantoea sp., and the fungi Cladosporium sp. and Candida sp. were the predominant genera. Fungi that are potential producers of mycotoxin were identified throughout the process, which indicates a risk of contamination since some of them are not degraded in the roasting process. Thirty-one species of microorganisms were described for the first time in coffee fermentation. The microbial community was influenced by the place where the process was carried out, mainly in relation to the diversity of fungi. Washing the coffee fruits before fermenting led to a fast reduction of pH; a fast development of Lactobacillus sp. and a fast dominance of Candida sp.; a reduction of the fermentation time necessary to achieve the best sensorial score; an increase in the invertase activity in the seed; a more expressive invertase activity in the husk; and a decreasing trend in polygalacturonase activity in the coffee husk. The increase in endo-β-mannanase activity suggests that coffee starts germinating during the process. SIAF has a huge potential to increase the quality and add value to coffee, but further studies must be conducted to access its safety. The study allowed a better knowledge of the spontaneous microbial community and the enzymes that were present in the fermentation process.
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  • 文章类型: Journal Article
    β-fructofuranosidase (FFase) from Aspergillus tamarii URM4634 was immobilized covalently in chitosan beads. It was characterized biochemically, studied in terms of kinetic and thermodynamic parameters, and applied on conversion of sucrose for invert sugar production in a packed bed reactor (PBR). The optimum reactional conditions were determined and obtained at pH 5.0 and 60 °C. FFase was thermostable at 50-55°C. At 50°C, the enzyme shows longer half-life (t1/2) (594.13 min) and a higher D-value (1,973.64 min). This indicates that immobilized FFase was stable at temperature commonly used in invert sugar production. The following thermodynamic parameters were obtained: activation energy (E*d = 301.57 kJ mol-1), enthalpy (298.76 ≤ ΔH*d ≤ 298.89 kJ mol-1), entropy (579.88 ≤ ΔS*d ≤ 589.27 J K-1 mol-1) and Gibbs free energy (100.29 ≤ ΔG*d ≤ 108.47 kJ mol-1). The high E*d, ΔH*d and ΔG*d values confirmed FFase thermostability. The high and positive values for ΔS*d indicate an increase in disorder due opening of the enzyme structure. The sucrose hydrolysis in PBR showed a maximum invert sugar yield (96.0%) at 15 min of operation. The hydrolysis process remained efficient up to 100 min (70.22%). The results obtained in the present study provide a good indication that immobilized FFase on chitosan beads in PBR is efficient to invert sugar production for food industry.
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  • 文章类型: Journal Article
    This study reports on the biochemical characterization as well as the kinetic and thermodynamic study of Aspergillus tamarii URM4634 β-fructofuranosidase (FFase) with transfructosylating activity. Conditions for FFase activity were optimized by means of a central composite rotational design using pH and temperature as the independent variables, while residual activity tests carried out in the temperature range of 45-65°C enabled us to investigate FFase thermostability and estimate the kinetic and thermodynamic parameters of enzyme denaturation. Optimal conditions for sucrose hydrolysis and fructosyl transfer catalyzed by crude FFase were 50°C, and pH 6.0 and 7.4, respectively. The thermodynamic properties of irreversible enzyme inactivation were found to be activation energy of 293.1 kJ mol-1 , and activation enthalpy, entropy, and Gibbs free energy in the ranges 290.3-290.4 kJ mol-1 , 568.7-571.0 J mol-1 K-1 , and 97.9-108.8 kJ mol-1 , respectively. The results obtained in this study point out satisfactory enzyme activity and thermostability at temperatures commonly used for industrial fructo-oligosaccharide (FOS) synthesis; therefore, this novel FFase appears to be a promising biocatalyst with great potential for long-term FOS synthesis and invert sugar production. To the best of our knowledge, this is the first report on kinetic and thermodynamic parameters of an A. tamarii FFase.
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  • 文章类型: Journal Article
    Study on 5 effective components and 6 soil enzyme activities of 2 different growth patterns, analyse the dates with the canonical correlation analysis, In order to reveal the relations between the effective components and soil enzyme activities. The result showed that they had a great relation between the effective components and soil enzyme activities, the activity of the same enzyme in humus soil was higher than that in farmland soil. Growth pattern of farmland soil, if the invertase and phosphatase activity were too high, which would inhibit the accumulation of total ginsenoside, water-miscible total proteins and total amino acid; Growth pattern of humus soil, if the invertase, urease and phosphatase activity were too high, which would inhibit the accumulation of total ginsenoside and the total essential oils. Integral soil enzyme activity can be used as a index of soil quality, which, together with other growth factors. The appropriate enzyme activity can accelerate the circulation and transformation of all kinds of material in the soil, improve effectively components accumulation.
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  • 文章类型: Comparative Study
    Yeast Saccharomyces cerevisiae is the most significant source of enzyme invertase. It is mainly used in the food industry as a soluble or immobilized enzyme. The greatest amount of invertase is located in the periplasmic space in yeast. In this work, it was isolated into two forms of enzyme from yeast S. cerevisiae cell, soluble and cell wall invertase (CWI). Both forms of enzyme showed same temperature optimum (60°C), similar pH optimum, and kinetic parameters. The significant difference between these biocatalysts was observed in their thermal stability, stability in urea and methanol solution. At 60°C, CWI had 1.7 times longer half-life than soluble enzyme, while at 70°C CWI showed 8.7 times longer half-life than soluble enzyme. After 2-hr of incubation in 8 M urea solution, soluble invertase and CWI retained 10 and 60% of its initial activity, respectively. During 22 hr of incubation of both enzymes in 30 and 40% methanol, soluble invertase was completely inactivated, while CWI changed its activity within the experimental error. Therefore, soluble invertase and CWI have not shown any substantial difference, but CWI showed better thermal stability and stability in some of the typical protein-denaturing agents.
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    文章类型: English Abstract
    OBJECTIVE: To study the activity of carbohydrase in model experimented on dogs.
    METHODS: The research was carried out on 20 adult mongrel dogs of both sexes weighing from 12 before 22 kg and consisted of two series of experiments. The first one was 12 animals with 50% wrap-retirement stenosis of the celiac trunk. In the second series of experiments consisted of 8 animals with 50% compression stenosis of the cranial brizee Noi artery. The activity of amidalas and sucrase were determined to wrap-retirement narrowing of the arteries and through 114-173 after stenosis.
    RESULTS: In conditions of chronic ischemia of the small intestine revealed as an increase in the activity of one, and unchanged levels of other Carbo-hydras: in biopsies of the mucosa of the proximal small intestine experienced dogs activity of pancreatic alpha-amylase stress-Valas is on average 13 times the original values, the activity of one membrane enzymes--gamma-amylase was increased by 4 times, the activity of another membrane enzyme sucrase remained without changes.
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  • 文章类型: Comparative Study
    Arabidopsis thaliana cell wall invertase 1 (AtcwINV1) and Thermotoga maritima β-fructosidase (BfrA) are among the best structurally studied members of the glycoside hydrolase family 32. Both enzymes hydrolyze sucrose as the main substrate but differ strongly in their thermal stability. Mesophilic AtcwINV1 and thermophilic BfrA have divergent sequence similarities in the N-terminal five bladed β-propeller catalytic domain (31 %) and the C-terminal β-sandwich domain (15 %) of unknown function. The two enzymes were subjected to 200 ns molecular dynamics simulations at 300 K (27 °C) and 353 K (80 °C). Regular secondary structure regions, but not loops, in AtcwINV1 and BfrA showed no significant fluctuation differences at both temperatures. BfrA was more rigid than AtcwINV1 at 300 K. The simulation at 353 K did not alter the structural stability of BfrA, but did increase the overall flexibility of AtcwINV1 exhibiting the most fluctuating regions in the β-propeller domain. The simulated heat treatment also increased the gyration radius and hydrophobic solvent accessible surface area of the plant enzyme, consistent with the initial steps of an unfolding process. The preservation of the conformational rigidity of BfrA at 353 K is linked to the shorter size of the protein loops. Shortening of BfrA loops appears to be a key mechanism for thermostability.
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  • 文章类型: Comparative Study
    Sucrose metabolism in roots of metallophytes is very important for root growth and maintenance of heavy metal tolerance. However, rare researches have been carried out on this topic so far. We tested here a hypothesis that roots of copper-tolerant plants should manifest higher activities of sucrose-cleaving enzymes than non-tolerant plants for maintaining root growth under Cu stress. Plants of two contrasting populations of metallophyte Rumex dentatus, one from an ancient Cu mine (MP) and the other from a non-mine site (NMP), were treated with Cu in controlled experiments. Cu treatment resulted in a higher root biomass and root/shoot biomass ratio in MP compared to NMP. More complicated root system architecture was showed in MP under Cu stress. Activities and transcript levels of acid invertase as well as contents of sucrose and reducing sugar in MP were elevated under Cu treatment, while activities of neutral/alkaline invertase and sucrose synthase showed no significant differences between two populations. The results indicate important roles of acid invertase in governing root growth under Cu stress.
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  • 文章类型: Journal Article
    我们使用基于DNA的焦磷酸测序技术来表征不同粪肥比例的苹果园沙质土壤的细菌群落结构。五个粪肥百分比(5%,10%,15%,20%和25%)进行了检查。对于每个重复获得超过10,000个有效读段。群落由五个优势群组成(变形杆菌,放线菌,氯氟菌,酸杆菌和拟杆菌),其中随着粪肥比例从0%增加到25%,变形杆菌含量从41.38%逐渐下降到37.29%,分别。冗余分析表明,37个类别与粪肥比例高度相关,其中18个呈正相关。聚类表明,根际样品分为三个部分:低肥料(对照,5%)处理,中等粪肥(10%,15%)处理和高肥(20%,25%)处理。维恩对这三组物种类型的分析表明,细菌群落差异主要反映在数量比而不是物种多样性上。尽管粪便含量增加导致土壤有机质含量增加,中肥改良土壤表现出最高的脲酶活性和糖酶活性,而5%至20%的粪肥比率提高也导致细菌多样性高于对照和25%的粪肥比率处理。我们的实验结果表明,使用适当的粪肥比例导致显著更高的土壤酶活性和不同的细菌群落模式,而使用过量的粪肥对土壤质量有负面影响。
    We used DNA-based pyrosequencing to characterize the bacterial community structure of the sandy soil of an apple orchard with different manure ratios. Five manure percentages (5%, 10%, 15%, 20% and 25%) were examined. More than 10,000 valid reads were obtained for each replicate. The communities were composed of five dominant groups (Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria and Bacteroidetes), of which Proteobacteria content gradually decreased from 41.38% to 37.29% as manure ratio increased from 0% to 25%, respectively. Redundancy analysis showed that 37 classes were highly correlated with manure ratio, 18 of which were positively correlated. Clustering revealed that the rhizosphere samples were grouped into three components: low manure (control, 5%) treatment, medium manure (10%, 15%) treatment and high manure (20%, 25%) treatment. Venn analysis of species types of these three groups revealed that the bacteria community difference was primarily reflected by quantity ratio rather than species variety. Although greater manure content led to higher soil organic matter content, the medium manure improved soil showed the highest urease activity and saccharase activity, while 5% to 20% manure ratio improvement also resulted in higher bacteria diversity than control and 25% manure ratio treatment. Our experimental results suggest that the use of a proper manure ratio results in significantly higher soil enzyme activity and different bacteria community patterns, whereas the use of excessive manure amounts has negative effect on soil quality.
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  • DOI:
    文章类型: Journal Article
    The physicochemical properties of soils might be changed under the long-term reclaimed water irrigation. Its effects on soil biological activities have received great attentions. We collected surface soil samples from urban green spaces and suburban farmlands of Beijing. Soil microbial biomass carbon (SMBC), five types of soil enzyme activities (urease, alkaline phosphatase, invertase, dehydrogenase and catalase) and physicochemical indicators in soils were measured subsequently. SMBC and enzyme activities from green land soils irrigated with reclaimed water were higher than that of control treatments using drinking water, but the difference is not significant in farmland. The SMBC increased by 60.1% and 14.2% than those control treatments in 0-20 cm soil layer of green land and farmland, respectively. Compared with their respective controls, the activities of enzymes in 0-20 cm soil layer of green land and farmland were enhanced by an average of 36.7% and 7.4%, respectively. Investigation of SMBC and enzyme activities decreased with increasing of soil depth. Significantly difference was found between 0-10 cm and 10-20 cm soil layer in green land. Soil biological activities were improved with long-term reclaimed water irrigation in Beijing.
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