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1.
Compounds from wild edible mushrooms has been reported to exert biological activities and contribute to the different flavors of mushrooms in our diet. Wild edible Boletus mushrooms are popular in Southwest China. In this study, we performed ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) based on widely targeted metabolomics analysis to identify key components. A total of 194 metabolites (113 upregulated, 81 downregulated) divided into 11 groups (49 metabolites in group lipids, 34 in amino acids and derivatives, 30 in organic acids, 18 in phenolic acids, 16 in nucleotides and derivatives, 13 in alkaloids, 6 in flavonoids, 3 in lignans and coumarins, 3 in tannins, 2 in terpenoids, and 20 in others) were found among Boletus bainiugan compared with B. subsplendidus. Through clustering analysis, principal component analysis (PCA), and orthogonal signal correction and partial least squares-discriminant analysis (OPLS-DA), different metabolites from fruiting bodies were clearly identified. Significant differences were observed in the metabolites between Boletus bainiugan and B. subsplendidus. These metabolites are involved in important biological functions. Our results provide new insights into important metabolites and theoretical basis for the taste difference of two wild edible Boletus mushrooms. 相似文献
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Although a total ban on the use of TBT coatings is not expected in the short term, there is a growing need for environmentally safe antifouling systems. To assist in the rapid screening of a large number of potential antifouling substances, a method that is simple, efficient and inexpensive is required. The production of byssus threads by the blue mussel, Mytilus edulis, has often been studied for testing the antifouling efficacy of various compounds. The present study reports a new antifouling assay based on the inhibition of purified M. edulis phenoloxidase activity. The method has the advantage of being specific, reliable, sensitive and rapid. 相似文献
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《Bioscience, biotechnology, and biochemistry》2013,77(5):1068-1074
We searched in this study for novel agonists of transient receptor potential cation channel, subfamily V, member 1 (TRPV1) and transient receptor potential cation channel, subfamily A, member 1 (TRPA1) in pepper, focusing attention on 19 compounds contained in black pepper. Almost all the compounds in HEK cells heterogeneously expressed TRPV1 or TRPA1, increased the intracellular Ca2+ concentration ([Ca2+]i) in a concentration-dependent manner. Among these, piperine, isopiperine, isochavicine, piperanine, pipernonaline, dehydropipernonaline, retrofractamide C, piperolein A, and piperolein B relatively strongly activated TRPV1. The EC50 values of these compounds for TRPV1 were 0.6–128 μM. Piperine, isopiperine, isochavicine, piperanine, piperolein A, piperolein B, and N-isobutyl-(2E,4E)-tetradeca-2,4-diamide also relatively strongly activated TRPA1, the EC50 values of these compounds for TRPA1 were 7.8–148 μM. The Ca2+ responses of these compounds for TRPV1 and TRPA1 were significantly suppressed by co-applying each antagonist. We identified in this study new transient receptor potential (TRP) agonists present in black pepper and found that piperine, isopiperine, isochavicine, piperanine, piperolein A, and piperolein B activated both TRPV1 and TRPA1. 相似文献
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2010年12月至2011年11月,利用涡度相关技术研究了我国亚热带(浙江)毛竹林生态系统的CO2通量,分析了毛竹林净生态系统交换量(NEE)、生态系统呼吸量(RE)和生态系统总交换量(GEE)的变化.结果表明: 研究期间,毛竹林各月的NEE均为负值,7月最大,为-99.33 g C·m-2,11月最小,仅-23.49 g C·m-2,其变化曲线呈双峰型.各月CO2通量平均日变化差异明显,9月最大,为-0.60 g CO2·m-2·s-1,1月最小,为-0.30 g CO2·m-2·s-1,且在NEE正负转换的时间点上呈明显的季节变化特征;全年RE呈单峰型变化,夏季最高、冬季最低,夜间RE与土壤温度呈极显著正相关.全年NEE、RE和GEE分别为-668.40、932.55和-1600.95 g C·m-2·a-1,NEE占GEE的41.8%.与其他生态系统相比,毛竹林的固碳能力极强. 相似文献
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Seed dispersal often limits tropical forest regeneration and animals disperse most rainforest tree seeds. This presents two important questions for restoration ecologists: (1) which animals are common seed dispersers? and (2) which restoration techniques attract them? Fourteen restoration sites were planted with four tree species in three designs, (1) controls (no planting, natural regeneration) (2) islands (trees planted in small patches), and (3) plantations (trees planted continuously over a large patch). We sampled birds in November, February, and April 2007–2008 with mist nets, in February and July 2009 with observations, and in July 2008 with both techniques. We documented 30 seed species from fecal samples of captured birds. All identified seed species were early‐successional forms. Four tanager species, three thrushes, two saltators, two flycatchers, and one finch were categorized as common seed dispersers, based on their high likelihood of dispersing seeds. Common dispersers were generalist species with small gape widths (<15 mm). Common dispersers were captured significantly more often in plantations than controls in most seasons and more often in plantations than islands during one season. Common disperser observations were significantly greater in plantations than controls during two periods and in plantations compared with islands in one period. Results indicate that plantation‐style planting is the conservative strategy to maximize attractiveness to common dispersers in tropical restoration sites. Island planting is an alternative when resources are limited although disperser activity may be lower in some seasons than in plantations. Additional research should investigate how to attract large, forest‐associated dispersers. 相似文献
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利用ITS 的通用引物(ITS5-ITS4) 对云南的美味牛肝菌( Boletus edulis) 子实体的DNA 进行PCR 扩增, 扩增产物回收后直接测序。序列的聚类分析表明, 在ITS1-5 . 8S rDNA-ITS2 区域, 云南的美味牛肝菌与欧洲的夏牛肝菌( B. aestivalis) 和铜色牛肝菌( B . aereus) 同源性较高, 但在ITS2 区域夏牛肝菌和铜色牛肝菌分别有一段美味牛肝菌没有的大小分别为73 bp 和26 bp 的特征序列。 相似文献
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