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Ochratoxin A (OTA) is known to be nephrotoxic and hepatotoxic in rodents when exposed orally. To understand the systematic responses to OTA exposure, GC-MS- and 1H-NMR-based metabolomic techniques together with histopathological assessments were applied to analyse the urine and plasma of OTA-exposed rats. It was found that OTA exposure caused significant elevation of amino acids (alanine, glycine, leucine etc.), pentose (ribose, glucitol, xylitol etc.) and nucleic acid metabolites (pseudouridine, adenosine, uridine). Moreover, myo-inositol, trimethylamine-oxide (TMAO), pseudouridine and leucine were identified as potential biomarkers for OTA toxicity. The primary pathways included the pentose phosphate pathway (PPP), the Krebs cycle (TCA), the creatine pathway and gluconeogenesis. The activated PPP was attributed to the high requirements for nicotinamide adenine dinucleotide phosphate (NADPH), which is involved in OTA metabolism through cytochrome P450. The elevated gluconeogenesis and TCA suggest that energy metabolism was involved. The up-regulated synthesis of creatinine reveals the elevated catabolism of proteins. These findings provide an overview of systematic responses to OTA exposure and metabolomic insight into the toxicological mechanism of OTA.  相似文献   

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ABSTRACT

There is a poor relationship between nutrient intake and existing nutritional biomarkers due to variety of factors affecting their sensitivity and specificity. To explore the impact of nutrients at molecular level and devising a sensitive biomarker, proteomics is a central technology with sirtuins as one of the most promising nutritional biomarker. Sirtuins (seven mammalian sirtuins reported so far) have been reported to perform protein deacetylases and ADP-ribosyltransferases activity. It is distributed in different cellular compartments thereby controlling several metabolic processes. Sirtuins are oxidized nicotinamide adenine dinucleotide dependent, which implicates a direct effect of the metabolic state of the cell on its activity. Calorie restriction upregulates the mammalian sirtuin protein levels in variety of tissues and organs where it acts upon both histone and nonhistone substrates. Sirtuin senses nutrient availability and impacts gluconeogenesis, glycolysis, and insulin sensitivity. It deacetylates and inhibits the nuclear receptor that activates fat synthesis and adipogenesis in the body, leading to fat loss and bringing favorable cellular and health changes. Sirtuins mediates intracellular response that promotes cell survival, DNA damage repair thereby increasing the cell longitivity. The activation of sirtuins brings a wide spectrum of other health benefits and its activity levels are indicative of nutritional status as well as disease progression in cancer, inflammation, obesity, cardiovascular diseases, and viral infections. There are several foods that activate sirtuin activity and offer significant health benefits by their consumption.  相似文献   

5.
Despite the development of silicone hydrogel lenses, Pseudomonas aeruginosa (PA) continues to be the leading cause of contact lens related microbial keratitis. Understanding the pathogenesis of PA-mediated corneal infection is critical to the development of new prevention and treatment strategies. Recently intracellular invasion of surface corneal epithelial cells by PA has been revisited as an important element in the infection process. This review identifies the mechanisms involved, and examines the roles of the lens, hypoxia alone, PA stain, cystic fibrosis transmembrane receptor protein (CFTR), and membrane lipid rafts in mediating intracellular invasion in both in vitro and in vivo conditions. Non-toxic blockade of raft formation in vitro or in vivo effectively abrogates PA internalization and may represent a unique, new strategy to prevent or ameliorate lens-related PA microbial keratitis.  相似文献   

6.
综述了辣椒碱的性质、提取方法及用途。列举了溶剂萃取法、微波法和超临界CO2流体萃取等典型的提取精制方法,并简要介绍了辣椒碱的应用前景。  相似文献   

7.
辣椒碱的提取和应用现状   总被引:1,自引:0,他引:1  
综述了辣椒碱的性质、提取方法及用途。列举了溶剂萃取法、微波法和超临界CO2流体萃取等典型的提取精制方法,并简要介绍了辣椒碱的应用前景。  相似文献   

8.
Recent research on the texture of fruits and vegetables is evaluated with regard to the relationship between the various facets of perceived texture such as cohesiveness, etc. and the geometrical, physical, and chemical properties of food. The role of polymeric materials such as pectin and cellulose, and their interaction with other components, receives special attention. Coming under consideration are the size of the cells, turgor and factors affecting it, the mechanical properties of cell walls and intercellular adhesion. The influences of storage, heat, chemicals, and enzymes on these characteristics provide insight into their fundamental contributions to texture. Further, the chemical composition and structural components of comminuted foods are related to their texture and rheology.  相似文献   

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Food Science and Biotechnology - Both spore and vegetative forms of Bacillus species have been used as probiotics, and they have high stability to the surrounding atmospheric conditions such as...  相似文献   

10.
Food Science and Biotechnology - The gut microbiome is the complex microbial ecosystem found in the gastrointestinal tract of humans and animals. It plays a vital role in host development,...  相似文献   

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In an effort to characterize colostrum microbial diversity and its potential associations with early-lactation clinical mastitis, we used high-throughput sequencing of the 16S rRNA gene to investigate the bovine colostrum microbiome. A prospective observational study was conducted that included 70 Holstein cows; colostrum samples were collected from all 4 mammary gland quarters. Colostrum samples were categorized according to whether the quarter was diagnosed (CMC) or not diagnosed (NCMC) with clinical mastitis during the first 30 d postpartum. Colostrum samples were dominated by Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Fusobacteria, and Tenericutes phyla, with the 6 most common taxa [order (o), family (f), and genus (g)] being g_Staphylococcus, g_Prevotella, f_Ruminococcaceae, o_Bacteroidales, o_Clostridiales, and g_Pseudomonas. The colostrum microbiota of primiparous cows was significantly richer (higher number of bacterial species) than that of multiparous cows, and differences in colostrum taxonomic structure between parities were also observed. The microbial community of NCMC samples of primiparous cows was significantly more diverse than that of CMC samples, and the relative abundances of the Tenericutes and Fusobacteria phyla as well as the Mycoplasma and Fusobacterium genera were significantly higher in NCMC than in CMC samples of primiparous cows. The colostrum core microbiome, defined as the bacterial taxa common to all colostrum samples examined, was composed of 20 taxa and included bacterial genera already known to be associated with mastitis (e.g., Staphylococcus, Mycoplasma, and Streptococcus spp.). Our results indicate that the colostrum microbiome of primiparous cows differs from that of multiparous cows, and it harbors some diversity and taxonomic markers of mammary gland health specific to primiparous cows only.  相似文献   

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The deposition and reentrainment of particles in porous media have been examined theoretically and experimentally. A Brownian Dynamics/Monte Carlo (MC/BD) model has been developed that simulates the movement of Brownian particles near a collector under "unfavorable" chemical conditions and allows deposition in primary and secondary minima. A simple Maxwell approach has been used to estimate particle attachment efficiency by assuming deposition in the secondary minimum and calculating the probability of reentrainment. The MC/BD simulations and the Maxwell calculations support an alternative view of the deposition and reentrainment of Brownian particles under unfavorable chemical conditions. These calculations indicate that deposition into and subsequent release from secondary minima can explain reported discrepancies between classic model predictions that assume irreversible deposition in a primary well and experimentally determined deposition efficiencies that are orders of magnitude larger than Interaction Force Boundary Layer (IFBL) predictions. The commonly used IFBL model, for example, is based on the notion of transport over an energy barrier into the primary well and does not address contributions of secondary minimum deposition. A simple Maxwell model based on deposition into and reentrainment from secondary minima is much more accurate in predicting deposition rates for column experiments at low ionic strengths. It also greatly reduces the substantial particle size effects inherent in IFBL models, wherein particle attachment rates are predicted to decrease significantly with increasing particle size. This view is consistent with recent work by others addressing the composition and structure of the first few nanometers at solid-water interfaces including research on modeling water at solid-liquid interfaces, surface speciation, interfacial force measurements, and the rheological properties of concentrated suspensions. It follows that deposition under these conditions will depend on the depth of the secondary minimum and that some transition between secondary and primary depositions should occur when the height of the energy barrier is on the order of several kT. When deposition in secondary minima predominates, observed deposition should increase with increasing ionic strength, particle size, and Hamaker constant. Since an equilibrium can develop between bound and bulk particles, the collision efficiency [alpha] can no longer be considered a constant for a given physical and chemical system. Rather, in many cases it can decrease over time until it eventually reaches zero as equilibrium is established.  相似文献   

13.
Plant metabolomics: potential for practical operation   总被引:1,自引:0,他引:1  
In the postgenomic era, metabolomics is expected to be the newest useful omics science for functional genomics. However, in plant science, the present metabolomics technology cannot be considered a universal tool to perfectly elucidate perturbations imposed on sample plants although this is desired by plant physiologists. Despite it being an immature technology, metabolomics has already been used as a powerful tool for precise phenotyping, particularly for industrial application. Metabolomics is the best technology for the analysis of large mutant or transgenic libraries of model experimental plants, such as Arabidopsis, rice, etc. Here, we review the applications and technical problems of metabolomics. We also suggest the potential of metabolomics for plant post-genomic science.  相似文献   

14.
中国酱油的现状及发展前景   总被引:3,自引:2,他引:3  
酱油起源于中国。我们的祖先通过长期生产实践的积累,巧妙的利用了自然条件,从各个方面不断总结和改进,创造了独特的酱油酿造工艺。近代,由于种种原因使得我国酱油酿造技术远远落后于其他发达国家。随着改革开放进程的加快,随着国家对科研投入力度的加大,在中国酱油人不断的努力下,相信在不久的将来,中国会让传统产品在世界舞台上焕发出现代科技的崭新活力。  相似文献   

15.
折璐  卜俊 《纺织报告》2020,(2):71-74
随着生活水平提高,人们对居住空间的舒适度和美观性要求也越来越高。从软装设计的概念、发展背景及应用现状出发,分析了软装设计的功能价值,并从品牌化、商业化、现代化、个性化、生态化5个方面对软装设计的未来发展趋势进行探讨。  相似文献   

16.
Abstract

Microbial exopolysaccharides (EPS) are an abundant and important group of compounds that can be secreted by bacteria, fungi and algae. The biotechnological production of these substances represents a faster alternative when compared to chemical and plant-derived production with the possibility of using industrial wastes as substrates, a feasible strategy after a comprehensive study of factors that may affect the synthesis by the chosen microorganism and desirable final product. Another possible difficulty could be the extraction and purification methods, a crucial part of the production of microbial polysaccharides, since different methods should be adopted. In this sense, this review aims to present the biotechnological production of microbial exopolysaccharides, exploring the production steps, optimization processes and current applications of these relevant bioproducts.  相似文献   

17.
Numerous studies have evaluated associations between bacterial groups and milk quality parameters. However, to our knowledge, no research has been published that has analyzed associations between the microbiome and quality parameters of bulk tank milk (BTM). Thus, the aims of this study were to identify the core microbiome of BTM and to examine associations between the microbiome and milk quality parameters. Four hundred seventy-two BTM samples from 19 different dairy farms located in New York State were analyzed by next-generation sequencing and quantitative PCR of the 16S rRNA gene to assess the milk microbiome and measure total bacterial load, respectively. Flow cytometry was used to determine bacterial and somatic cell counts. Heatmaps were constructed and simple linear regressions and response screening analysis were performed. To facilitate data analysis and interpretation of the results, we dichotomized the BTM samples into high (HSCC, >200,000) and low somatic cell count (LSCC, ≤200,000) and into high (HSPC, >3.6) and low log10 SPC (LSPC, ≤3.6). Spoilage-causing, spore-forming, and pathogenic bacteria of importance to the dairy industry were identified in the core microbiome. In addition, the taxa Thermoanaerobacterium and 5–7N15 were identified in the core microbiome; to our knowledge, these genera have not been previously identified in milk samples. Several bacterial genera were encountered in significantly higher relative abundances in the HSCC group when compared with the LSCC group, including Corynebacterium, Streptococcus, Lactobacillus, Coxiella, Arthrobacter, and Lactococcus. Additionally, several bacterial taxa were found in significantly higher relative abundances in the HSPC groups versus the LSPC groups: Acinetobacter, Enterobacteriaceae, Corynebacterium, and Streptococcus. In addition, Streptococcus was highly correlated with HSPC, and this genus was the second most abundant bacterial taxon detected in samples classified as HSCC. Bacterial diversity (Shannon index) was negatively correlated with bacterial load, suggesting that the microbiomes of high-bacterial load BTM samples are dominated by smaller groups of bacterial taxa. In conclusion, the associations described corroborated current knowledge about pathogens and spoilage bacteria in relationship to milk quality, and also indicated that other bacterial taxa should be a focus of further investigations.  相似文献   

18.
Most fermented products are generated by a mixture of microbes. These microbial consortia perform various biological activities responsible for the nutritional, hygienic, and aromatic qualities of the product. Wine is no exception. Substantial yeast and bacterial biodiversity is observed on grapes, and in both must and wine. The diverse microorganisms present interact throughout the winemaking process. The interactions modulate the hygienic and sensorial properties of the wine. Many studies have been conducted to elucidate the nature of these interactions, with the aim of establishing better control of the two fermentations occurring during wine processing. However, wine is a very complex medium making such studies difficult. In this review, we present the current state of research on microbial interactions in wines. We consider the different kinds of interactions between different microorganisms together with the consequences of these interactions. We underline the major challenges to obtaining a better understanding of how microbes interact. Finally, strategies and methodologies that may help unravel microbe interactions in wine are suggested.  相似文献   

19.
海藻糖的研究现状及其应用前景   总被引:28,自引:4,他引:28  
综述海藻糖的理化特性、生物活性、生产制备及应用前景。海藻糖对生物物质具有保护作用。制备方法包括微生物提取法、微生物发酵法、酶合成法和基因工程法等。海藻糖广泛应用于生物药物、食品及化妆品等行业。  相似文献   

20.
《食品与发酵工业》2014,(11):182-187
乳蛋白是生命最初阶段中最重要的营养物质,利用蛋白质组学技术能够直观、整体地研究乳蛋白质的组成与调控生命的活动规律,可以更全面、深入地阐明乳蛋白质的表达信息。通过阐述蛋白质组学在人乳与牛乳蛋白研究中的应用进展,以及乳酪蛋白质组学、乳清蛋白质组学、乳脂肪球膜蛋白质组学、乳铁蛋白质组学的研究,为寻找疾病的临床诊断和治疗、乳品加工保存条件、开发新型婴幼儿食品提供重要的理论依据。  相似文献   

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