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41.
Shoujiao Li Ana Barreiro Erik Steen Jensen Yingjun Zhang 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(2):165-175
ABSTRACTThe global interest in growing perennial grain crops such as intermediate wheatgrass (Thinopyrum intermedium) (Kernza) for production of food and feed is increasing. Intercropping Kernza with legumes may be a sustainable way of supplying nitrogen to soil and associated intercrop. We determined the competitive interactions between intercropped Kernza (K) and alfalfa (Medicago sativa L.) (A) under three inorganic nitrogen (N) rates N0, N1, N2 (0, 200, 400 kg ha?1) and five species relative frequencies (SRF) (100%K:0%A, 75%K:25%A, 50%K:50%A, 25%K:75%A and 0% K:100%A) in mixed intercrops (MI) in a greenhouse pot experiment. After 11 weeks of growth. Kernza dry matter yield (DM) and N accumulated (NACC) were low, but alfalfa DM and NACC high at 0 kg N ha?1. 200 and 400 kg N ha?1 fertiliser application increased the competitive ability (CA) of Kernza and reduced the CA of alfalfa. SRF had large impacts on alfalfa DM, NACC and NFIX only at 0 kg N ha?1 fertiliser, and insignificant impacts on Kernza at all N fertiliser levels, indicating that adjustment of SRF may not be an effective way to modulate the interspecific competition of Kernza. Further research on the other factors that influence the interspecific competition are warranted. 相似文献
42.
基于UPLC-QTOF/MS的小麦发芽代谢组学分析方法 总被引:1,自引:0,他引:1
为探究不同提取方法对发芽小麦代谢物提取效果的影响,本研究建立了基于超高效液相色谱-四级杆飞行时间质谱(UPLC-QTOF/MS)的发芽小麦非靶向代谢组学样品前处理方法和分析方法,以发芽2 d周麦26籽粒为材料,设计提取溶剂、提取方式、提取时间3个因素在3个水平上L9(34)正交试验,并通过主成分分析和聚类分析确定提取效果最佳的组合。以80%乙腈(0.1%甲酸)震摇提取30 min可检测出1609个代谢峰,说明提取溶剂对代谢物提取效果起主要作用。共鉴定出92种小麦代谢物。 相似文献
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This experiment was conducted to investigate the liver-protective effect of Chinese herbal compound probiotics (CHCP) on acute liver injury layers.One hundred and eight 1 day old hens were divided into 4 groups with 3 replicates in each group and 9 layers per replicate in trial 1.The layers in model groups Ⅰ to Ⅲ were gavaged with 10% (V/V) soybean oil solution of carbon tetrachloride (SCCl4) according to 1,2 and 4 mL/(kg·BW) at 14,28 and 35 d,respectively.The layers in control group were gavaged with 2 mL/(kg·BW) soybean oil.In trial 2,sixty 1 d layers were divided into 5 groups:Control group (soybean oil),model control group(SCCl4)and low-dose,middle-dose and high-dose CHCP group (SCCl4+1‰ CHCP,SCCl4+2‰ CHCP and SCCl4+4‰ CHCP respectively).CHCP were used by drinking water since 7 days.SCCl4 were gavaged according to 2 mL/(kg·BW) at 14 and 28 d.The results showed as follows:The model of layers liver damage could be built by intragastric administration of 2 mL/(kg·BW) 10%(V/V) SCCl4 at 14,28 d respectively,with the signs of hepatic steatosis,severe vacuolar degeneration,nuclear condensation and necrosis.Compared to the model control group,the serum AST levels in low,medium and high dose CHCP groups were decreased by 4.35% (P > 0.05),7.57% (P > 0.05) and 9.79% (P < 0.05),the serum ALT levels in medium and high dose CHCP groups were decreased by 34.92% (P < 0.01),36.51% (P < 0.01),the serum total bilirubin content in medium and high dose CHCP groups were decreased by 25.49% (P < 0.01),27.45% (P < 0.01).The liver cell congestion was reduced to varying degrees in different dose CHCP groups,and the liver cell had no vacuoles,arranged in neat rows,abundant cytoplasm and uniform in different dose CHCP groups.In conclusion,2‰,4‰ CHCP could reduce hepatocyte necrosis,decrease the serum activities of ALT,AST and total bilirubin levels,and had protective effect on hepatic injury induced by SCCl4. 相似文献
45.
不同的样本特性和提取方法对获得微生物总DNA的质量有重要影响。文章基于高含固率木质纤维素厌氧发酵物腐殖酸、酚类物质含量高、质地均一性差、微生物浓度低的特点,研究了4种方法提取不同高含固率粪秸厌氧发酵物中微生物总DNA的效果。结果表明,常规的十二烷基磺酸钠法(sodium dodecyl sulfate,SDS)、十二烷基磺酸钠和溴化十六烷基三甲铵结合法(sodium dodecyl sulfate and cetyltrimethyl ammonium bromide,SDS-CTAB)和商业的粪便试剂盒法提取的DNA质量均较差,SDS法和试剂盒法未能获得聚合酶链式反应(polymerase chain reaction,PCR)扩增目的条带,SDS-CTAB法得到的条带较模糊;改进SDS-CTAB法获得的DNA杂质少、纯度高,具有较好的稳定性,A260/A280和A260/A230值分别为1.74~1.86和1.65~1.86,每克样品的DNA浓度在50 ng·μL^-1以上,电泳条带单一齐整、清晰明亮,PCR扩增的目的条带清晰度高,适宜后续分子生物学技术的分析。林格氏液洗脱、聚乙烯吡咯烷酮-40(Polyvinyl Pyrrolidone-40,PVP-40)洗涤液除杂以及裂解液和多种酶联合破壁是改进SDS-CTAB法获得该类专一性样本高质量微生物总DNA的关键步骤。 相似文献
46.
本研究以三七(Panax notoginseng)植株及其产品和近缘种为研究对象,采用L9(3 4)正交试验对三七素的提取工艺进行了优化,然后利用HPLC法检测三七素含量,并对各样品中的三七素含量进行了比较分析。结果表明:优化后的三七素提取条件为超纯水、料液比1∶20(g/mL),提取1次(10 min);三七素在三七花蕾中的含量最高,其次是根状茎和主根,但是三七茎叶中也有较高含量的三七素,说明三七花蕾和茎叶均可作为三七素的提取原料;在三七产品中三七花的三七素含量最高,达到3.33%,其次是剪口(根状茎)、筋条(侧根)和须根;但三七素的含量与三七个头大小(头数)并无明显的相关性;在三七近缘种姜状三七(P. zingiberensis)和野三七(P. vienamensis var. fuscidiscus)主根、珠子参(P. japonicus var. major)根状茎中的三七素含量显著低于三七主根三七素含量,也显著低于三七其他部位的三七素含量,说明三七是最佳的三七素来源植物。三七素的含量主要受到物种和部位的影响,与产品规格无关。本文所建立的三七素提取方法和HPLC检测方法,能够快速简便、稳定可靠测定样品中三七素含量;并可为三七素相关标准的建立奠定基础,为三七的综合利用开发提供依据。 相似文献
47.
为降低油菜种子中的亚油酸和亚麻酸含量并使之在异交条件下保持基本稳定,以高油品种CY2作为受体亲本,采用RNA干涉技术沉默油菜内源Bn FAD2基因的表达,抑制油酸脱饱和反应。育成的3个独立转基因株系的亚油酸和亚麻酸含量下降到6%以下,其中亚油酸含量较受体亲本降低78.2%~86.5%,亚麻酸含量降低53.4%~65.8%。将3个转基因株系与2个亚油酸和亚麻酸含量较高的常规品种正反交,F1种子中这2种脂肪酸的含量依然保持在与转基因亲本相仿的低水平。由此可知,通过RNA干涉技术沉默Bn FAD2基因的表达可赋予油菜低亚油酸和亚麻酸含量的异交稳定特性。这一特性的获得对于今后培育异交稳定的高油酸油菜新品种具有重要意义。 相似文献
48.
建立了使用Waters UPLC Xevo TQ超高效液相色谱串联质谱仪检测水产品中4种硝基呋喃代谢物的分析方法。匀浆后的样品在酸性环境下水解,并用2-硝基苯甲醛衍生16h,经磷酸氢二钾提取,LMS固相萃取小柱净化后,在三重四极杆多反应监测模式下进行测定。方法采用同位素内标法定量,四种代谢物的检出限(LOD)均低于0.25μg·kg-1,线性范围在0.5μg·L~(-1)到10μg·L~(-1)间,相关系数大于0.99。在0.5、1.0和5μg·kg-1浓度下分别进行添加回收试验(n=5),回收率在75.2%~123.3%之间,相对标准偏差(RSD)小于9.4%。 相似文献
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50.
A method for fractionating sorghum proteins using extraction solvents and techniques designed to obtain polymeric protein structures (especially disulfide linked) was developed. Extraction and separation conditions were optimized in terms of completeness of protein extraction, sample stability, and analytical resolution. After pre-extraction of albumins and globulins, a 3-step sequential procedure involving no reducing agents was applied to ground whole sorghum flour. The three fractions obtained represented proportionally different protein polymer contents and molecular weight distribution as evidenced by comparative size exclusion chromatography. Protein composition also varied among the extracts with differences in kafirin composition and non-kafirin proteins detected in the fractions by RP-HPLC and SDS-PAGE analysis. The ability to quantify and further characterize sorghum polymeric protein complexes will be useful for additional studies linking protein structures with functionality and digestibility and variations for these properties within diverse sorghum germplasm. 相似文献