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101.
Hydrogen cyanide (HCN) poisoning due to amygdalin (AMY) in apricot seeds is one of the public health issues in Turkey. The aim of this study was to investigate the AMY content of 13 different apricot seeds including bitter and sweet ones, and which are either sulfurized or roasted. The AMY content was determined by a high-performance liquid chromatography. Release of HCN was predicted and total amount of seeds which can cause poisoning was calculated. The mean AMY content of bitter seeds was 26 ± 14 mg g?1 and that of sweet seeds was 0.16 ± 0.09 mg g?1. The consumption of small amounts of bitter seeds may cause cyanide poisoning.  相似文献   
102.
The condensation of substituted cinnamaldehydes and arylacetonitriles using sodium ethoxide in ethanol at room temperature afforded 2,5‐diaryl‐2,4‐pentadienenitriles in good yield. The structure of the reaction products was established on the basis of their infrared, nuclear magnetic resonance and elemental analysis data. Two representative compounds were studied for their mutagenic activity. One of them showed a weak mutagenicity while the second showed a high mutagenic activity in TA97a Salmonella strain. Both were negative in TA100. Some of these pentadienenitriles showed fluorescence in solutions.  相似文献   
103.
A highly sensitive enzyme immunoassay was standardized for aflatoxin B1 determination in poultry feed and its components using Riedel-de-Haen, ELISA Systems. A microtitration plate method was optimized using anti-aflatoxin B1 antibodies and peroxidase – aflatoxin B1 conjugate, based on competitive enzyme immunoassay principle. Standards of concentrations of 5, 10, 20, 50, 100, 500?ng/L aflatoxin B1, prepared in phosphate-buffered saline, were used. Standard curves showed that as the concentration of antigen decreased, absorbance values increased. Fifty percent inhibition was observed at 37?ng/L. Regression analysis showed that log concentration was inversely related to %B/B0, with a highly significant negative correlation (?0.980). The lowest detection limit for aflatoxin B1 was 5?ng/L. Using this standardized ELISA, aflatoxin B1 was detected in most of the commercially available poultry feed samples and their components.

The data suggest that this test is suitable for the accurate determination of aflatoxin B1 concentrations in poultry feed and its components.  相似文献   
104.
Zero tillage is recognized as a potential measure to sequester carbon dioxide in soils and to reduce CO2 emissions from arable lands. An up-scaling approach of the output of the Environmental Policy Integrated Climate (EPIC) model with the information system SLISYS-BW has been used to estimate the CO2-mitigation potential in the state of Baden-Württemberg (SW-Germany). The state territory of 35,742 km2 is subdivided into eight agro-ecological zones (AEZ), which have been further subdivided into a total of 3976 spatial response units. Annual CO2-mitigation rates where estimated from the changes in soil organic carbon content comparing 30 years simulations under conventional and zero tillage. Special attention was given to the influence of tillage practices on the losses of organic carbon through soil erosion, and consequently on the calculation of CO2-mitigation rates. Under conventional tillage, mean carbon losses through erosion in the AEZ were estimated to be up to 0.45 Mg C ha−1 a−1. The apparent CO2-mitigation rate for the conversion from conventional to zero tillage ranges from 0.08 to 1.82 Mg C ha−1 a−1 in the eight AEZ, if the carbon losses through soil erosion are included in the calculations. However, the higher carbon losses under conventional tillage compared to zero tillage are composed of both, losses through enhanced CO2 emissions, and losses through intensified soil erosion. The adjusted net CO2-mitigation rates of zero tillage, subtracting the reduced carbon losses through soil erosion, are between 0.07 and 1.27 Mg C ha−1 a−1 and the estimated net mitigation rate for the entire state amounts to 285 Gg C a−1. This equals to 1045 Gg CO2-equivalents per year with the cropping patterns in the reference year 2000. The results call attention to the necessity to revise those estimation methods for CO2-mitigation which are exclusively or predominantly based on the measurements of differential changes in total soil organic carbon without taking into account the tillage effects on carbon losses through soil erosion.  相似文献   
105.
A rapid method for the extraction and monitoring of nanogram level of Pb2+ and Cu2+ ions using uniform silanized mesopor (SBA-15) functionalized with aminobenzenesulfonamide groups and flame atomic absorption spectrometry (FAAS) is presented. Aminobenzenesulfonamide functionalized SBA-15 was synthesized according to procedure in the literature and the presence of organic groups in the silica framework was demonstrated by FT-IR spectra. The functionalized product showed the BET surface area 110 m2/g and pore diameter 5.1 nm, based on adsorption-desorption of N2 at 77 K. The effect of several variables such as (amount of adsorbent, stirring time, pH and presence of other ions in the medium) has been studied. Lead and copper were completely extracted at pH greater than 3 after stirring for 10 min. The maximum capacity of the adsorbent was found to be 191.3 ± 1.4 and 155.0 ± 1.0 μg of lead and copper ions/mg functionalized SBA-15, respectively. The preconcentration factor of the method was found to be 200. The detection limit of the technique was 3.4 and 0.4 ng/mL for Pb2+ and Cu2+, respectively. The applications of this methodology for real samples were examined by various water type, black tea and pepper samples.  相似文献   
106.
极端嗜热菌海栖热袍菌木聚糖酶B的克隆和表达   总被引:3,自引:0,他引:3  
极端嗜热菌海栖热袍菌MSB8(ThermotogamaritimaMSB8)能够利用木聚糖代谢 ,并具有两个产木聚糖酶的基因 .本研究首次克隆和在大肠杆菌中表达海栖热袍菌MSB8的第 2个木聚糖酶基因即xynB基因 .以基因组DNA为模板 ,根据xynB基因的全序列设计了两对引物 ,在合适的PCR反应条件下有效地扩增出了xynB基因片段 .选用pET2 8a(+)表达载体 ,NcoI-HindⅢ酶切位点并编码了羧基端 6×His标签的阳性克隆表达成可溶且具有生物活性的蛋白质 .xynB结构基因由 10 4 4对碱基组成 ,编码 347个氨基酸 .根据已知木聚糖酶蛋白质氨基酸的同源性分析 ,XynB与T .sp.strainFjSS3-B .1的XynA的同源性最大 ,为 85 % ,与T .neapolitana的XynB同源性次之 ,为 82 % ,与其它木聚糖酶的同源性小于 4 3% .另外 ,XynB属于F/ 10族木聚糖酶 ,且含有单一功能区 .表 3图 3参 12  相似文献   
107.
Environmental Science and Pollution Research - In this study, the air pollution–related quality of life (AP-QOL) questionnaire was carried out in two geographically and economically different...  相似文献   
108.
Environmental Science and Pollution Research - This study aims to analyze the correlation between the daily confirmed COVID-19 cases in Jordan and metrological parameters including the average...  相似文献   
109.
Environmental Science and Pollution Research - Heat shock proteins (HSPs) are a family of proteins that are expressed by cells in reply to stressors. The changes in concentration of HSPs could be...  相似文献   
110.
Environmental Science and Pollution Research - Wind energy is considered one of the most efficient and cost-effective ways to generate electricity, since it has a low environmental impact. So, it...  相似文献   
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