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41.
42.
Doongar R. Chaudhary Richard P. Dick 《Communications in Soil Science and Plant Analysis》2016,47(9):1193-1206
Photosynthetically derived rhizodeposits are an important source of carbon (C) for microbes in root vicinity and can influence the microbial community dynamics. Pulse labeling of carbon dioxide (13CO2) coupled with stable isotope probing techniques have potential to track recently fixed photosynthate into rhizosphere microbial taxa. Therefore, the present investigation assessed the microbial community change associated with the rhizosphere and bulk soil in Jatropha curcas L. (a biofuel crop) by combining phospholipid fatty acid (13C-PLFA) profiling using a stable isotope 13CO2 labeling approach. The labeling (13C) took place after 45 days of germination, PLFAs were extracted from both soils (rhizosphere and bulk) after 1 and 20 days pulse labeling and analyzed by gas chromatography-isotope ratio mass spectrometry. There was no significant temporal effect on the PLFA profiles in the bulk soil, but significantly increased abundance of Gram positive (i15:0) and Gram negative (16:1ω7c and 16:1ω5c) biomarkers was observed in the rhizosphere soil from day 1 to day 20 after labeling. The Gram negative (16:1ω7c) decreased and fungal (18:2ω6,9c) increased significantly in rhizospheric soil compared to bulk soil after day 1 of labeling. Whereas, after 20 days of labeling, the Gram negative biomarker (16:1ω7c and 18:1ω7c) decreased and Gram positive (a15:0) increased significantly in rhizospheric soil compared to bulk soil. One day following labeling, i15:0, a15:0, i16:0, 16:1ω5c, 16:0, i17:0, a17:0, 18:2ω6,9c, 18:1ω9c, and 18:0 PLFAs were significantly more enriched in δ13C in the rhizosphere than in the bulk soil. Twenty days after labeling, 16:1ω5c (Gram negative) and 18:2ω6,9c (fungal) were significantly more enriched in δ13C in the rhizosphere than in the bulk soil. These results shows the effectives of PLFA coupled using the pulse chase labeling technique to examine the microbial community changes in response to recently fixed photosynthetic C flow in rhizodeposits. 相似文献
43.
为丰富羊乳产品,开阔羊乳市场,给消费者带来更多的消费选择,实验以山羊乳、麦芽、红枣、酒花为主要原料,分别通过乳酸菌的乳酸发酵和酵母菌的酒精发酵后,将得到的红枣羊乳酸液和啤酒原浆按一定体积比配比,制备出兼具酸乳、啤酒、碳酸饮料风味和保健功能的新型红枣羊乳啤饮料,并通过测定沉淀率和稳定系数对其稳定性进行分析。结果表明:当红枣羊乳酸液与啤酒原浆的体积比为1∶1,红枣羊乳酸液中红枣汁添加量12%、羧甲基纤维素钠添加量0.2%、果胶添加量0.15%、蔗糖酯添加量0.1%、白砂糖添加量4%时生产的红枣羊乳啤口感最佳,稳定性最好。 相似文献
44.
We investigated the behavior of biochars in arable and forest soil in a greenhouse experiment in order to prove that these amendments can increase carbon storage in soils. Two qualities of biochar were produced by hydrothermal pyrolysis from 13C labeled glucose (0% N) and yeast (5% N), respectively. We quantified respiratory losses of soil and biochar carbon and calculated mean residence times of the biochars using the isotopic label. Extraction of phospholipid fatty acids from soil at the beginning and after 4 months of incubation was used to quantify changes in microbial biomass and to identify microbial groups utilizing the biochars. Mean residence times varied between 4 and 29 years, depending on soil type and quality of biochar. Yeast-derived biochar promoted fungi in the soil, while glucose-derived biochar was utilized by Gram-negative bacteria. Our results suggest that residence times of biochar in soils can be manipulated with the aim to “design” the best possible biochar for a given soil type. 相似文献
45.
SHENDe-chao 《东北农业大学学报(英文版)》2004,11(1):72-76
The properties of saccharified and boiled worts between extruded and traditional non-extruded beer adjuncts were studied at the laboratory and a small beer brewing equipment(100L) in this paper. Test results indicate that the main saccharification indices and filtration speeds of worts between extruded and traditional non-extruded beer adjuncts are similar basically. The collected rate of extracted material of worts of extruded beer adjuncts is 8% more than that of traditional non-extruded beer adjuncts. Fermentation time of worts of extruded beer adjuncts is 10% less than that of traditional non-extruded beer adjuncts. The energy consumption of extruded beer adjuncts in saccharification process is 13% less than that of traditional non-extruded beer adjuncts. 相似文献
46.
MOHAMED H. ABUSHHIWA NOURIA S. SALEHI ROBERT C. WHITTON JENNIFER A. CHARLES PETER J. FINNIN PETER M. LORDING BRUCE W. PARRY 《Veterinary radiology & ultrasound》2009,50(5):545-549
Technetium-99m stannous colloid (99m TcSnC) has been used to radiolabel human leukocytes to investigate various inflammatory disorders. We investigated the in vitro behavior of feline leukocytes labeled in whole blood with 99m TcSnC. Heparinized blood samples were collected from healthy cats and divided into control and test aliquots. The latter were labeled with 99m TcSnC using a standard procedure. Leukocyte viability was determined for each sample using a trypan blue exclusion test. Labeling efficiency was determined for test aliquots. Test aliquots were layered onto Histopaque-1077® and centrifuged before measurement of radioactivity of the blood components. Leukocytes from radiolabeled and control samples were washed and incubated with opsonized zymosan particles to allow assessment of phagocytic function. Aliquots were taken from radiolabeled feline leukocyte samples at 1, 3, 4, and 7 h postlabelling. After centrifugation of each aliquot, radioactivity of the supernatant and pellet was measured and the labeling retention determined. Leukocyte viability in both radiolabeled and control samples was >98%. The labeling efficiency was 95.2±0.14%. The distribution of radioactivity in feline blood was found to be 3.4±0.18% in plasma, 39.0±0.37% in erythrocytes, and 57.6±0.38% in leukocytes. Labeled feline leukocytes had phagocytic activity of 90.9±0.18% (control 91.3±0.15%). The radiolabeled leukocytes retained 93.4±0.19% of the radioactivity up to 7 h postlabeling. 99m TcSnC efficiently labeled feline leukocytes with no effect on viability and minimal effect on phagocytic function. The percentage retention of radioactivity by the leukocytes was still high at 7 h postlabeling. 相似文献
47.
[目的]利用5条引物目的片段进行扩增,完成PRINS检测中引物及其退火温度的测定.[方法]采用确认带有ASPV的库尔勒香梨叶片,以叶片为试验材料,并采用经RT - PCR检测技术健康香梨的叶片作为阴性对照.引物采用NCBI提供的BLAST工具中的ASPV病毒的全基因组序列的外壳蛋白的保守区域进行设计.并根据PRINS特有的性质及ASPV病毒有片断相互重叠现象来设计相应的引物.[结果]这5条引物之间没有太多的干扰,且都在目的区域出现了比较清晰的条带.[结论]证明所设计引物可以在进一步的PRINS检测ASPV病毒时直接使用,为PRINS在梨树病毒检测方面发挥更大的作用奠定了基础. 相似文献
48.
啤酒营养与保健作用的研究进展 总被引:2,自引:0,他引:2
啤酒是以大麦芽、啤酒花、酵母等原料酿造而成的一种低酒度(3%)饮品。啤酒营养丰富,含多种人体必需氨基酸、维生素和微量元素,以及生物活性物质,如多酚和黄酮类化合物等,饮用后对人体的多种生理功能具有调节作用。其药理和保健作用有:防止动脉硬化和心脏病、抑制癌症、促进血液循环、改善免疫机能、抗氧化与抗衰老、促进雌激素分泌、减轻放射线损害、预防白内障、解除肾结石、镇静、活化胃、促进食欲等。 相似文献
49.
饲喂鲜啤酒糟对奶牛产奶性能的影响 总被引:1,自引:0,他引:1
为了探索鲜啤酒糟对奶牛产奶性能的影响,以贵阳三联孔业有限公司第二奶牛场的87头泌乳牛为试验材料,根据市场饲料价格的变化及各种饲料的供应情况,逐步降低精料的喂量,增加鲜啤酒糟的喂量,并适当调整青贮玉米及青绿饲料的喂量,以保证奶牛正常的营养需要及适宜的精粗比,重点对奶牛的生产性能及所产生的经济效益进行了分析.试验结果表明,当精料喂量为7.20kg,鲜啤酒糟喂量达到10.30kg时,奶牛平均泌乳单产最高(14.45 kg),毛利润为13.68元/(头·日);当精料喂量6.10kg,鲜啤酒糟喂量达到11.70 kg时,毛利润达最高,为15.02元/(头·日). 相似文献
50.
利用正交试验对猪细小病毒(PPV)N株在IBRS-2细胞转瓶培养中的培养条件进行优化,为PPV N株弱毒疫苗的大量培养工艺提供参考.设细胞培养液pH值(7.0、7.2和7.4)、接毒时间(0、24和48 h)、接毒剂量(0.10%、1.00%和10.00%)、收毒时间(48、72和96 h)等因子和水平.结果表明,PPV N株转瓶培养的最佳培养条件组合为细胞培养液pH值7.2,采用同步接毒,接毒剂量为0.10%,收毒时间为接毒后96 h.其中收毒时间是影响PPV N株毒价的最主要因素. 相似文献