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51.
A non-specific lipid-transfer peptide (nsLTP) with fungicidal activity was isolated from Daucus carota sativa carrot seeds. Peptides were purified by a method including aqueous extraction, anion-exchange chromatography over CM-TSK-650M, and HPLC over a column of 250/8/4 Protein@Peptide C18 using an acetonitrile gradient. The molecular weight of the peptide was determined as 9624 Da by mass spectrometry. The peptide was found to have fungicidal activity against the pathogenic fungus Verticillium dahliae. The partial N-terminal sequence, which was highly homologous to the N-terminal sequences of lipid-transfer peptides from seeds of rice, tobacco, and maize, was determined using Edman automated sequencing. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 371–373, July–August, 2007.  相似文献   
52.
The aim of the present study was to magnetize Plantago ovata Forssk. hydrogel and produce a nanosphere system to carrier mefenamic acid as the drug model. For this propose, P. ovata seeds hydrogel (POSH) was extracted and magnetized by Fe3O4 being functionalized using tetraethyl orthosilicate and trimethoxyvinysilane. Thereafter, mefenamic acid (MFA) was loaded on the carrier system. The final product, as the magnetic drug loaded nanosphere (Fe/POSH/MFA), was fully characterized through different techniques involving X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating-sample magnetometer (VSM), thermal gravimetric analysis (TGA), dynamic light scattering (DLS), and FT-IR spectroscopy. The results confirmed the successful production of the drug loaded nanosphere system with particles magnetization of 25 emu/g over a range size of 40–50 nm. However, the size distribution less than 100 nm was measured through DLS analysis. The hydrogel showed a pH sensitivity swelling behavior representing the best efficacy at pH 7.4. The efficiency of the drug encapsulation was found to be 64.35%. The drug releasing was studied using a dialysis bag at pH = 7.4. The highest in vitro drug releasing was found to be 57.3 ± 0.6% after 72 h, as well. The findings of the current report account for the potential use of P. ovata hydrogel as an effective delivery system for encapsulation of water insoluble basic drugs, e.g., MFA in a magnetized carrier system.  相似文献   
53.
钛硅沸石合成中各组分作用研究   总被引:6,自引:2,他引:4  
李钢  赵琦 《燃料化学学报》1999,27(6):565-567
1983年Taramasso等[1]报导了钛硅沸石TS-1的合成。由于在用稀H2O2为氧化剂的低温氧化反应中TS-1的突出催化性能,所以近年来钛硅沸石的合成、表征及催化应用研究一直是热点课题。经典的钛硅沸石合成需要采用昂贵的模板剂-不含碱金属离子的四丙基氢氧化铵(T...  相似文献   
54.
Tomato producing and processing industries present undoubted potential for industrial discarded products valorization whether due to the overproduction of fresh tomatoes or to the loss during processing. Although tomato by-products are not yet considered a raw material, several studies have suggested innovative and profitable applications. It is often referred to as “tomato pomace” and is quite rich in a variety of bioactive compounds. Lycopene, vitamin C, β-carotene, phenolic compounds, and tocopherol are some of the bioactives herein discussed. Tomato by-products are also rich in minerals. Many of these compounds are powerful antioxidants with anti-inflammatory properties besides modulating the immune system. Several researchers have focused on the possible application of natural ingredients, especially those extracted from foods, and their physiological and pharmacological effects. Herein, the effects of processing and further applications of the bioactive compounds present in tomato by-products were carefully reviewed, especially regarding the anti-inflammatory and anti-cancer effects. The aim of this review was thus to highlight the existing opportunities to create profitable and innovative applications for tomato by-products in health context.  相似文献   
55.
阴阳离子交换色谱串联分离纯化苦瓜籽核糖体失活蛋白   总被引:11,自引:0,他引:11  
将阴阳离子交换色谱柱在灌注色谱工作站上串联,使苦瓜籽粗提液中未被阴离子色谱柱吸附的蛋白质直接在阳离子色谱柱上吸附,用盐线性梯度洗脱从阳离子色谱柱上分离出两个具有抗真菌活性的蛋白。两个抗真菌蛋白经鉴定都达到了电泳纯,相对分子质量均为30000左右,N-端氨基酸序列分别为DVSFRLSGADPRSYGMFI与DVNFDLSTATAK,表明所得到的两种蛋白为苦瓜籽中的2个Ⅰ型核糖体失活蛋白α-苦瓜素(α-MMC) 和β-苦瓜素(β-MMC)。抗菌实验表明,α-MMC对香蕉枯萎菌和果腐霉菌均具有较强的抑制作用,β  相似文献   
56.
From the seeds of medicianl plant koelreuteria paniculata,a new pseudo sesquiter-penoid with novel skeleton namely paniculoid 1 was isolated,The structure of 1 was established on the basis of extensive 2D NMR spectroscopy in conjugation with MS and IR spectral analysis.  相似文献   
57.
航天诱变育种甜椒品系的红外光谱分析   总被引:5,自引:2,他引:3  
首次采用傅里叶变换红外光谱法(FTIR)对航天诱变育种甜椒品系种子和一般大田生产的甜椒品种种子进行了对比研究,比较了它们红外光谱的异同。甜椒种子的红外光谱主要由蛋白质的吸收带和碳水化合物的吸收带组成。航天育种的两个甜椒品系种子(SP11和SP18)红外光谱的主要吸收峰的峰位、峰形与普通甜椒品系种子相同,表明经航天诱变的甜椒其主要化学成分和基本结构并未发生变化。太空甜椒种子,在2 854,1 652, 1 542以及1 160~1 062 cm-1范围内的吸收都较普通甜椒种子增加。2 855 cm-1峰是CH2—伸缩振动,1 652 cm-1处的吸收峰为酰胺Ⅰ带,是CO的伸缩振动峰,1 542 cm-1的吸收峰是酰胺Ⅱ带,是N—H的弯曲振动和C—N的伸缩振动,1 160 cm-1处的峰可能为碳水化合物的C—O的伸缩振动引起。表明航天诱变使甜椒种子的蛋白质和碳水化合物含量增加。  相似文献   
58.
基于水稻种子近红外特征光谱的品种鉴别方法研究   总被引:2,自引:0,他引:2  
本文用MPA傅立叶变换近红外光谱仪研究了单粒水稻种子的漫反射光谱特征,发现颖壳对光谱扫描有影响,为了尽量消除这种影响,保证光谱的代表性,应对其上下表面分别进行多次光谱采集,取它们的平均光谱。本文利用种子品种特有的光谱特性,结合不同光谱预处理方法建立了多个聚类分析模型,比较它们对杂交F1代种子"03S/0412"和其父本种子"0412"的鉴别效果。结果显示:选择40008900cm-1光谱范围,通过"无预处理"、"矢量归一化"、"二阶导数(25点平滑)"和"二阶导数(25点平滑)+矢量归一化"建立的模型校正集正确率分别为52.4%、65.2%、75.2%和100%,可见,相比无预处理,经过各种预处理后正确率都有提高,其中"二阶导数(25点平滑)+矢量归一化"建立的模型最好,用该模型对预测集预测,分类正确率也为100%,具有很好的预测性能。这说明近红外光谱技术可用于单粒水稻种子品种真伪性鉴别。  相似文献   
59.
60.
In this article, the use of date stones (thrown as a waste material) as adsorbent for the removal of a variety of adsorbates in aqueous and gaseous streams have been reviewed. Adsorption plays a role in the wastewater treatment as a polishing process, especially on activated carbon at tertiary treatments. In this review, the preparation and characterization technique along with the applications of the date stones as adsorbent has been presented in detail. A comprehensive study and the comparison of the available data in literature reveal that the date stones can be used as a potential adsorbent for a wide variety of toxic contaminants such as dyes, heavy metals, insecticides, etc.  相似文献   
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