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81.
为探究不同的提取条件对合欢磁牡口服液质量的影响,以确定最佳的提取工艺。通过不同的提取工艺、浓缩工艺及提取工艺验证试验处理后,检测合欢磁牡口服液中(-)-丁香树脂酚-4-O-β-D-呋喃芹糖基-(1→2)-β-D-吡喃葡萄糖苷(C_(33)H_(44)O_(17))的含量。结果显示,煎煮次数C对提取工艺有显著影响(P0.01);煎煮时间B和加水量A对提取工艺无显著影响(P0.05);不同的浓缩温度对合欢磁牡口服液含量无显著影响(P0.05),采用本试验确定的最佳工艺提取的合欢磁牡口服液中C_(33)H_(44)O_(17)的转移率平均值为72.37%,RSD为0.83%。因此,确定的最佳提取生产工艺为8倍量水,提取3次,每次煮沸1 h。  相似文献   
82.
何美悦 《农业工程》2019,9(9):108-112
在食品发酵行业中压缩空气脱水不足会造成发酵染菌,同时发酵罐的发酵液随尾气排出罐体时,会造成生产产量降低及造成空气二次污染,加大发酵染菌机率,导致停产。针对行业需求,本文介绍了一种新型气液分离器,该设备与同类产品相比有较高的分离效率。   相似文献   
83.
As laid down by the Codex Alimentarius, products bearing a gluten-free label must not contain gluten levels above 20 mg/kg to be safe for consumption by celiac disease patients. Analytical methods to detect gluten from wheat, rye and barley need to be sufficiently sensitive, specific, suitable for routine analyses and validated by collaborative studies. With continuous progress in the field of gluten analysis, the aim of this paper is to provide an up-to-date overview of legislation regarding gluten-free products worldwide, as well as immunochemical, proteomics-based, genomics-based and other methods designed to analyse gluten traces. While ELISA test kits and PCR are still most widely used in quality control, liquid chromatography tandem mass spectrometry (LC-MS/MS) is gaining more and more importance by providing unprecedented insights into gluten. Several other methods such as immunosensors, other sensors and microarrays are being developed. The pro's and con's of the different methods are discussed as well as the remaining challenges, including the need for improved extraction procedures, comprehensive reference materials and independent reference methods.  相似文献   
84.
家蚕蛾油对蛹虫草液体发酵培养的影响   总被引:1,自引:0,他引:1  
通过对蛹虫草菌丝体干产量以及胞外高分子聚合物和胞内多糖含量的测量分析,研究了添加家蚕蛾油对蛹虫草(Cordyceps militarisL.)液体发酵培养效果的影响。添加4%雄蚕蛾油或2%雌蚕蛾油,蛹虫草菌丝体的产量分别增加76.1%和45.9%,胞外高分子聚合物含量分别增加64.2%和43.0%,均达到最大值;添加3%雄蚕蛾油或雌蚕蛾油使胞内多糖含量分别增加46.8%和47.1%,菌丝体产量分别增加145%和102%,均达到最大值。结果表明,添加一定量的家蚕蛾油对蛹虫草液体发酵培养具有促进作用,而在作用效果上,家蚕雄蛾油要优于家蚕雌蛾油。  相似文献   
85.
(目的和方法)为研究添加胰岛素对IUGR新生仔猪胰腺重量、酶活性的影响,试验选择初生IUGR仔猪15头,分为新生对照组(N)、牛乳组(M)和试验组即牛乳添加胰岛素(60 IU/L)组(I),人工饲喂3 d后宰杀取样。(结果)结果显示,与N组相比,饲喂3 d后,M组和I组仔猪胰腺重量、胰腺重/体重、蛋白质含量、DNA含量、RNA含量、胰淀粉酶活性、胰脂肪酶总活性、胰高血糖素总含量均不同程度提高,而胰总蛋白水解酶活性、胰蛋白酶活性、胰糜蛋白酶总活性、胰腺胰岛素总含量均不同程度降低,变化较明显。与M组相比,I组胰腺蛋白质含量、蛋白质/DNA比值分别提高了61.43%、60.54%(P0.01);I组胰总蛋白水解酶活性、胰淀粉酶活性、胰脂肪酶总活性、胰腺胰岛素总含量、胰高血糖素含量分别提高了10.59%、10.40%、9.37%、14.30%、12.30%(P0.05);胰腺重、胰腺重/体重、胰腺DNA含量、RNA含量、RNA/DNA比值也不同程度提高(P0.05);而I组与M组间胰蛋白酶活性、胰糜蛋白酶活性差异不显著。(结论)表明IUGR仔猪生后胰腺生长发育较迅速,添加胰岛素能在一定程度上刺激IUGR仔猪胰腺细胞增殖和增大,能显著促进IUGR仔猪胰腺蛋白质合成和沉积,有刺激胰腺内外分泌部发育、提高胰腺酶活性提高、刺激组织激素分泌的趋势,对IUGR仔猪出生后胰腺的生长具有一定的补偿作用。  相似文献   
86.
Pit fractures of refractory coniferous heartwoods caused by precompression in the radial direction were investigated and are discussed in terms of improved liquid penetration. Small cracks appeared at the boundary between the torus and margo, along the outer margin of the margo, and on the torus when specimens were compressed and deformation was fixed by drying. The remarkable cracks were generally observed for Cryptomeria japonica D. Don. Pseudotsuga menziesii Franco showed peculiar detachment of the torus from the pit border, and Larix leptolepis Gordon exhibited only small cracks on the torus. These fractures patterns were clearer when the precompressed specimens were recovered by water impregnation and then redried.This report was presented at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, April 1996  相似文献   
87.
本文对杉木新造林地进行了水土保持观测,取得了研究数据和科学结论,以指导杉木造林。1径流场地点基本情况径流场地位于湖南省浏阳县张访林场,地处幕阜山系大围山南麓。多年平均降水量15523mm,历年日最大降水量为2761mm(19650706),年...  相似文献   
88.
Passive immunisation of fish was conducted to determine whether anti-Vibrio anguillarum whole sera (AVA) and affinity-purified AVA raised in sheep, rabbits and rainbow trout (Oncorhynchus mykiss) were persistent when injected and orally administered into rainbow trout. These responses were compared with active immunisation by immersion in, and intraperitoneal (i.p.) injection with, formalin-killed V. anguillarum cells. Sheep and rabbit AVA were detected in rainbow trout sera for up to 70 days (half-life 21 days) after i.p. injection as determined by an enzyme-linked immunosorbent assay (ELISA). The relative percentage survival (RPS) of passively immunised rainbow trout challenged with virulent V. anguillarum after an injection was comparable to that of active immunisation by immersion after 1 month post-immunisation (p.i). Affinity-purified sheep and rabbit AVA exhibited the same protective potential as whole serum in rainbow trout. Rabbit and sheep immune sera diluted 1:8 and 1:50, respectively, provided equivalent protection as undiluted fish immune serum. An active immune response against passively acquired heterologous immunoglobulins was demonstrated by ELISA, with responses against sheep AVA being less than those against rabbit AVA. Rainbow trout given purified sheep AVA conjugated to LTB (the GM-1-binding subunit of Escherichia coli heat-labile toxin) and administered orally had an RPS of 37.5% at 15 days and 27% at 1 month p.i. In contrast, fish given sheep AVA conjugated to TraT (an internal membrane of E. coli) or in micellar form with Quil-A had RPSs of only 18.7 and 6.2%, respectively, after 15 days, and 13.3 and 0% after 1 month, respectively. The protection conferred by immune sera was shown to be due to the immunoglobulin component alone. Heat inactivation of the complement in sera had no effect on the potency of immune sera.  相似文献   
89.
用HPLC法测定动物肌肉中的磺胺类药物   总被引:6,自引:0,他引:6  
七种动物肌肉组织中残留的磺胺间甲氧嘧啶(SMM)、磺胺地索辛(SDM)、磺胺二甲氧嘧啶(SM2)、磺胺甲恶唑(SMZ)、磺胺喹恶啉(SQ)经乙腈提取,正己烷分配,再经碱性氧化铝SPE柱净化后,用高效液相色谱-紫外检测法测定。该方法的最低检测限为2μg/kg,最低检出限为10μg/kg,回收率为60%-110%,批内变异系数小于15%,批间变异系数小于20%。  相似文献   
90.
以杏鲍菇(Pleurotus eryngii)的4个品种为试材,采用液体发酵培养的方法,测量液体发酵过程中菌丝球密度、干重、直径以及发酵液pH值、还原糖等指标,研究液体发酵过程中菌丝球的生长情况及发酵液的变化;并通过感官检测、显微镜观察和菌丝球回接试验探索优良的液态杏鲍菇菌丝体的感官指标、生化指标和微生物学指标.结果表明:优质杏鲍菇液体菌种质量标准具体为菌液为淡黄色澄清状,含浓郁的苦杏仁味,无杂菌污染;菌丝球肉眼可见,洁白、均匀、表面有毛刺、直径<2.5 mm且浓度达到80%~ 100%;显微镜下菌丝体粗壮,每个视野有3~4个锁状联合;一般发酵时间为120-144 h.  相似文献   
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