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101.
Hypercholesterolemia initiates the atherogenic process; however, chronic inflammation promotes atherogenesis. Monascus spp. fermented products are recognized for their anti-hypercholesterolemic effect, but their anti-inflammatory activity is not as significant as that of many plant-derived foods. To enhance the anti-inflammatory function of Monascus pilosus fermented products, ginger was added to the PDB medium at a ratio of 20% (v/v). The mycelia and broth were collected, freeze-dried, and extracted by ethanol for assays. Macrophage RAW264.7 was challenged with lipopolysaccharide (LPS) and coincubated with the extracts of fermented product cultured in ginger-supplemented medium (MPG) or extracts of fermented product cultured in regular PDB medium (MP) for 18 h. Human umbilical vein endothelial cell HUVEC was challenged with tumor necrosis factor (TNF)-α and coincubated with the extracts of either MPG or MP for 6 h. The results showed that MPG significantly (p<0.05) lowered the production of macrophage pro-inflammatory cytokines TNF-α, nitric oxide (NO), interleukin (IL)-1, IL-6, and prostaglandin E2 (PGE2) by 68.53%, 84.29%, 32.55%, 84.49%, and 69.49%, respectively; however, MP had no inhibitory effect. MPG significantly downregulated the expression of p-IκB, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) in macrophage by 42.16%, 50.87%, and 51.35%, respectively, while MP had no inhibition on COX-2 expression and only 16.64% and 19.22% downregulatory effect on iNOS and phosphorylated-IκB (p-IκB), respectively. Moreover, MPG significantly suppressed the expression of vessel cell adhesion molecule-1 (VCAM-1) and p-IκB in endothelial cell by 63.48% and 63.41%, respectively. LC/MS/MS analysis indicated that 6-gingerdiol was formed in the ginger-modified medium during fermentation. The results of this study will facilitate the development of Monascus spp. fermented products as antiatherosclerotic nutraceuticals.  相似文献   
102.

Purpose

Knowledge of archaeal communities is essential for understanding of the mechanism of carbon and nitrogen cycle in the mangrove sediment ecosystem. Presently, little is known about archaeal communities in the Dongzhaigang mangrove sediments. This study aimed to characterize the archaeal communities in sediments of different mangrove stands and to find out the correlations between archaeal communities and the environmental factors of sediments.

Materials and methods

Sediment samples were collected from the Dongzhaigang mangrove forest for analysis of soil properties and archaeal communities, by national standard methods and Illumina Miseq archaeal 16S ribosomal RNA (rRNA) gene sequencing, respectively.

Results and discussion

The archaeal community in the Dongzhaigang mangrove forest was constituted by some phyla from “TACK” and “DPANN” supergroups, and dominated by Euryarchaeota. Among sediments of the four mangroves in Dongzhaigang, principal coordinates analysis (PCoA) scatter plot showed a trend of difference in the archaeal community structure in the Bruguiera gymnoihiza and Kandelia candel stands from that in the Laguncularia racemosa and Sonneratia apetala stands. The abundance of the order Methanosarcinales was the highest in the sediments of K. candel mangroves, whereas the order of Methanobacteriales dominated in B. gymnoihiza sediments. The highest richness and diversity values of Archaea occurred in K. candel sediments, while the lowest in B. gymnoihiza. Pearson correlation showed the significant relationships between sediment properties and some dominant genera, with a positive and significant correlation between sediment properties and genus Methanobacterium, coinciding with the maximum values of sediment properties and abundance of Methanobacterium in the sediment of B. gymnoihiza. Such results indicated that the difference of archaeal community structure among mangrove sediments may be caused by the different sediment characteristics. Methanogenic communities in the Dongzhaigang mangrove forest sediments were, at the order level, constituted by Methanobacteriales, Methanomicrobiales, Methanosarcinales, and Methanomassiliicoccales.

Conclusions

The investigation indicated that the Dongzhaigang mangrove sediment ecosystems support diverse archaeal communities and methanogenic communities, and that there was a general trend of difference in the archaeal community structure in the B. gymnoihiza and K. candel mangrove sediments from that in the L. racemosa and S. apetala sediments. Such difference may be caused by the difference in sediment characteristics.
  相似文献   
103.
A simple electrochemical approach, which does not require any expensive and complex instruments, is established for the selective and quantitative recognition of melamine in diary products and pet foods. During a preconcentration step (at 1.8 V versus Ag/AgCl), the formation of a polymer film from melamine on a preanodized screen-printed carbon electrode was identified by SEM and XPS. The as-formed polymer was found to be electroactive with a reversible redox peak, and hence square-wave voltammetry was applied to further increase the detection sensitivity to meet the detection limit for application in real sample analysis. Simply with a medium exchange procedure, melamine was selectively detected with a detection limit (S/N=3) of 0.8 μM (i.e., 98.3 ppb) by square-wave voltammetry. Lower than 1 ppm of melamine in real samples can be easily detected with good recoveries of 98.7-100.9% by the proposed approach. The recovery tests established for external calibration and standard addition techniques verified that the analysis can be done in a single-run measurement.  相似文献   
104.
Naturally high total dissolved solids and upstream agricultural runoff often mask the influence of urban land cover on stream chemistry and biology. We examined the influence of headwater urbanization on the water chemistry, microbiology, and fish communities of the Big Brushy Creek watershed, a 96 km2 drainage basin in the piedmont of South Carolina, USA. Concentrations of most major anions and cations (especially nitrate, sulfate, chloride, sodium, potassium, and calcium) were highest in the urban headwaters and decreased downstream. Generally, the highest concentrations of suspended coliform bacteria occurred in the urban headwaters. In contrast, stream habitat quality and the abundance, species richness, and species diversity of fishes did not differ significantly between urban and rural sites. Discharge of wastewater treatment plant effluent at one rural location caused an increase in concentrations of many solutes and possibly the abundance of benthic algae. We hypothesize that atmospheric dry deposition and domestic animal wastes are important sources of stream solutes and of coliform bacteria, respectively, in the urban headwaters. The lack of significant differences in fish abundance and diversity between urban and rural sites may indicate that urban development in the Big Brushy Creek watershed has not yet degraded habitat conditions greatly for stream fishes. Alternatively, agriculture or other land uses may have degraded stream habitat quality throughout the watershed prior to urbanization.  相似文献   
105.
猪粪堆肥臭气产生与调控的研究   总被引:30,自引:4,他引:30  
通过两次室外中型堆肥试验,研究在相同水分条件(68.8%),不同调理剂、不同碳氮比(C/N)、不同通气方式以及不同添加剂对猪粪堆肥过程中臭气产生与控制的影响。研究表明:猪粪堆肥中,臭气的主要形式是氨气,主要产生在堆肥的升温及高温期。降低堆肥的pH值、增加微生物对NH+4-N的固定等是控制臭气的有效措施;过磷酸钙添加量为1.5%时,可以降低堆肥的pH值,使NH3浓度减小,促进NH+4-N向其它形式的氮转变,且不影响堆肥的腐熟;除臭剂试验组堆肥过程中臭味小,堆肥结束后的物理性状最好,不影响猪粪堆肥进程,可在生产中推广。  相似文献   
106.
魔芋是世界上迄今为止发现的唯一能大量提供葡甘聚糖的经济植物资源,其胶溶性、凝胶性、成膜性及与其他植物胶的优良复配性等优点在食品、医疗、化工、石油、造纸等工业生产中具有广泛的作用,加上魔芋种植条件极其苛刻、产地局限,且繁殖系数极低,病害难以控制,使魔芋产品市场无论是国内还是国际始终处于供不应求状态。  相似文献   
107.
我国甘蔗机械化成本分析及机收效益评价模型的建立   总被引:2,自引:0,他引:2  
张华  罗俊  廖平伟  郭伟 《热带作物学报》2010,31(10):1669-1673
对耕整地、种植、中耕培土及收获环节的机械化生产方式与常规生产方式的成本进行比较分析。结果显示,人工支出在常规生产方式的成本构成中所占比重最大,以机械替代人、畜力节约生产成本14.19%,其中以种植机械化的节约幅度最大,收获在机械化各环节成本构成中所占比重最大,凸显其重要性。并研究建立了"公顷纯收入"的多元线性回归模型,各自变量的贡献由大到小依次为:甘蔗单产、甘蔗收购价、肥料成本、委托机收费用。  相似文献   
108.
探讨了和谐社会建设中高校信息社会化服务的意义。从高校如何利用自身的技术、资源、人员等优势实现信息社会化服务进行了分析,指出信息社会化服务是和谐社会建设及高校自身发展的必要条件。  相似文献   
109.
大型烟囱一般是工业厂区的高耸建筑,经过几十年的使用,需要重新鉴定其结构可靠性,烟囱的垂直度,是一个很重要的安全指标。由于烟囱为圆形截面,不能直接测量,而且工业厂区内建筑较多,通视条件较差,给测量带来很多困难。通过测量烟囱上下两个标高处的外轮廓水平角度,换算出上下标高处的相对水平偏移角,再用角度交汇方法求出最终偏移值,经过精度分析,完全满足工程精度要求。本文以上海某大型烟囱为例,提出了对已有烟囱垂直度偏差的检测方法,以用于大型服役烟囱的监测。  相似文献   
110.
浅谈我国木薯种收机械化技术   总被引:3,自引:0,他引:3  
阐述了我国木薯种植、收获机械化技术发展的必要性以及发展现状,同时对我国木薯种收机械化技术发展面临的诸多问题做了详细分析,针对性地提出了解决影响木薯种收机械化技术的对策和几点建议。  相似文献   
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