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有机肥对蕨麻生长及块根产量的影响   总被引:1,自引:0,他引:1  
以蕨麻为研究对象,观测了不同有机肥水平对其生长和块根产量的影响.试验结果表明:施入有机肥对蕨麻基株的复叶数、复叶长度,匍匐茎数量无显著影响,但可以显著提高匍匐茎的长度、粗度和分株数.有机肥能明显提高蕨麻块根的产量,其中c处理的产量最高,比对照增产55.61%;B、D、E处理分别比对照增产14.09%、21.56%和27.10%.  相似文献   
2.
利用红外图谱法建立了蕨麻的红外指纹图谱.采用小波分析对红外光谱图进行去噪后,再把去噪后的光谱原始数据长度由1 868压缩到241,通过压缩后的数据对11批蕨麻进行了相似度计算和灰色关联度分析.结果表明,所建立的蕨麻的指纹图谱可用于蕨麻的质量评价.  相似文献   
3.
建立了一种同时测定动物源提取物中肌肽(Carnosine)和鹅肌肽(Anserine)含量的超高效液相色谱-电喷雾串联三重四极杆质谱(UHPLC-ESI-MS/MS)分析方法。采用超高效液相分离系统,借助Inertsil Amide HP色谱柱(2. 1 mm×100 mm,3μm)以0. 1%乙酸水溶液-乙腈为流动相,梯度洗脱分离,利用峰面积外标法定量。经过优化,肌肽和鹅肌肽在1. 95~500μg/L质量浓度范围内与峰面积呈良好的线性关系,相关系数(r)均大于0. 998。肌肽和鹅肌肽的检出限分别为0. 12、0. 47μg/L。以低浓度低聚肽原料为基质,在低、中、高3个加标浓度下,肌肽的回收率为99. 3%~109%,相对标准偏差(RSD,n=6)为0. 98%~1. 1%;鹅肌肽的回收率为100%~113%,RSD为1. 0%~1. 1%。该法前处理简单、快速,重现性好,准确度高,适用于动物源食物提取物中肌肽和鹅肌肽的同时快速检测。  相似文献   
4.
将不同地区的蕨麻在西宁驯化栽培,通过对其生育期的观察以及对蕨麻种植地耕层土壤N、P、K、有机质养分变化情况的测定,得出:不同地区的蕨麻其各生育期的持续时问不同,造成了不同的吸肥要求.蕨麻对土壤有机质的需求在整个生长季节不大,且不同生态地区的蕨麻间无显著差异;蕨麻对土壤速效氮的吸收主要在匍匐期和花果期,大通蕨麻对速效氮的消耗量最大,其次是门源、刚察;土壤速效磷主要在基株生长期和块根膨大期被吸收,土壤速效磷消耗量从大到小依次为门源、大通、刚察;土壤速效钾也主要在基株生长期和块根膨大期被吸收,消耗量从大到小依次为刚察、门源、大通.  相似文献   
5.
The nuclear magnetic resonance (NMR) technique was used as analytical tool to determine the complete metabolic profiling of sea bass extracts: water-soluble metabolites belonging to different classes such as sugars, amino acids, dipeptides and organic acids as well as metabolites soluble in organic solvent such as lipids, sterols and fatty acids were identified. The metabolite profiling together with a suitable statistical analysis were used to discriminate between wild and cultured sea bass samples. Preliminary results show that discrimination between wild and cultured sea bass was obtained not only using fatty acid composition but also cholesterol and phosphatidylethanolamine and some water-soluble metabolites such as choline, trimethylamine oxide, glutamine, fumaric and malic acids.  相似文献   
6.
朱作艺  张玉  王君虹  李雪  王伟  杨华  朱岩 《色谱》2018,36(12):1297-1302
建立了一种离子色谱-积分脉冲安培(IC-IPAD)同时测定肉类样品中鹅肌肽、高肌肽及肌肽的分析方法。方法采用高效阴离子交换色谱柱AminoPac PA10(250 mm×2 mm)分离,以100 mmol/L NaOH为淋洗液,流速为0.2 mL/min,柱温为30℃。结果表明,3种目标化合物在15 min内可实现完全分离,且17种氨基酸对3种目标化合物不存在干扰。在最佳色谱条件下,鹅肌肽、高肌肽及肌肽在0.05~5.0 mg/L范围内呈良好的线性关系,线性相关系数(r)>0.99。3种目标化合物的检出限和定量限分别为8.9~22.1 μg/L和29.6~73.6 μg/L。对鸭胸及鹅胸样品进行分析,加标回收率为92.4%~104.5%。该方法简单方便,无需衍生化,灵敏度高,可用于肉类产品中相关营养成分的测定。  相似文献   
7.
The histidine-containing dipeptides carnosine (CAR) and structurally related anserine (ANS) and homocarnosine (HCAR), widely distributed in vertebrate organisms, have recently been proposed as endogenous quenchers for highly cytotoxic alpha,beta-unsaturated aldehydes generated by peroxidation. A sensitive, selective, specific and rapid liquid chromatographic/electrospray ionization tandem mass spectrometric assay was developed and validated for the simultaneous determination of these peptides in biological matrices in order to establish their plasma/tissue distribution. Samples (plasma or tissue homogenates from male rats) were prepared by protein precipitation with HClO(4) (1 : 1, v/v) containing H-Tyr-His-OH as internal standard. The supernatant was separated on a Phenomenex Sinergy polar-RP column with a mobile phase of water-acetonitrile-heptafluorobutyric acid (9 : 1 : 0.01, v/v/v) at a flow-rate of 0.2 ml min(-1), with a run time of 10 min. Detection was effected on an ion trap mass spectrometer equipped with an electrospray ionization interface operating in positive ionization mode. The acquisitions were in the multiple reaction monitoring mode using the following precursor --> product ion combinations: H-Tyr-His-OH (internal standard) m/z 319 --> 301; CAR m/z 227 --> 210 + 209; ANS m/z 241 --> 224 + 197 + 170; HCAR m/z 241 --> 156. The method was validated over the concentration range 15-1000 nmol g(-1) and the limit of quantification (LOQ) and limit of detection (LOD) were 12.5 and 4.2 pmol injected, respectively. The intra- and inter-day precisions were <10% (< or =17.47% at the LOQ) and the intra- and inter-assay accuracies were within +/-10% for all concentrations. The mapping profile in rat tissue gave the following results: the highest concentrations of CAR and ANS were found in skeletal muscles (soleus, gastrocnemius, tibialis), followed by the heart, cerebellum and brain (ANS below the LOQ). HCAR was found only in the brain and cerebellum. No histidine-containing dipeptides were detectable in plasma, liver, kidney and lung.  相似文献   
8.
蕨麻水溶性多糖的提取及其单糖组分的分析   总被引:3,自引:0,他引:3  
本文采用热水提取、乙醇沉淀、a-淀粉酶法脱淀粉、链酶蛋白酶和Sevag法联合除蛋白,得到蕨麻多糖.对提取的蕨麻多糖进行了总糖含量及糖醛酸含量的测定.粗多糖(P1)总糖含量为41.8%,糖醛酸含量为11.1%.脱淀粉脱蛋白多糖(P2)总糖含量为39.4%,糖醛酸含量为35.9%.经纸层析和高效液相色谱分析,表明该多糖主要由阿拉伯糖、鼠李糖、葡萄糖、半乳糖、半乳糖醛酸组成,说明蕨麻多糖为酸性杂多糖.  相似文献   
9.
A field amplified sample injection (FASI) capillary electrophoresis method with UV detection was developed for the separation and detection of carnosine-related peptides carnosine (Car), anserine (Ans) and homocarnosine (Hcar). The imidazole dipeptides were baseline-separated within 10 min by using 50 mmol/L Tris phosphate pH 2.2 as running buffer. The samples were diluted in water and directly injected on the capillary without complex cleanup and/or sample derivatization procedures. Using the electrokinetic injection, a sensitivity improvement of about 500-fold was achieved without any loss of separation efficiency if compared to the conventional sample injection. The detection limits for carnosine, anserine, and homocarnosine were between 0.4 and 0.5 nmol/L, thus improving of 10-100-fold the LOD of previous described methods based on laser induced fluorescence or chemiluminescence detection. This method has been applied to the analysis of homogenized rat tissue (heart, muscle and brain) and human cerebrospinal fluid (CSF).  相似文献   
10.
Cheese ripening involves a number of biochemical processes, mainly of a proteolytic nature, which are initially triggered principally by milk-coagulating enzymes and, afterward, by microorganisms or enzymes of microbial origin. The proteolytic reactions affect, primarily, the synthesis of macro- and medium-molecular peptides from casein. In turn, the advanced proteolysis ends in the formation of short peptides and free amino acids. Further reactions may lead to the formation of nutritionally unfavorable biogenic amines. The present study aimed to determine changes in the contents of bioactive peptides (anserine and L-carnosine), free amino acids, and biogenic amines throughout the ripening of cheese models produced with the addition of Lactobacillus genus bacteria. The contents of amino acids varied considerably in the cheese models, depending on the bacterial strain added and ripening time. After five weeks of ripening, the total content of free amino acids in the cheese models ranged from 611.02 (a cheese model with Lactobacillus casei 2639) to 1596.64 mg kg−1 (a cheese model with Lb. acidophilus 2499). After the same time, the contents of the total biogenic amines in the cheese models with the addition of lactobacilli were lower than in the control cheese model (except for the model with Lb. rhamnosus 489). Anserine was detected in all cheese models (79.29–119.02 mg kg−1), whereas no L-carnosine was found over a five-week ripening period in the cheese models with Lb. delbrueckii 490 and Lb. casei 2639. After a five-week ripening, the highest total content of bioactive peptides was determined in the cheese models containing Lb. acidophilus 2499 (136.11 mg kg−1).  相似文献   
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