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971.
Triglycerides from Urena lobata   总被引:1,自引:0,他引:1  
Two triglycerides, both bearing polyunsaturated fatty acid residues, were isolated from the hexane extract of Urena lobata. One of them is characterized by the presence of three different polyunsaturated fatty acids. Their structures were studied with spectral methods.  相似文献   
972.
选用360只60~70周龄海兰褐蛋鸡,研究不同种类的多不饱和脂肪酸(PUFA)在不同添加水平下对产蛋鸡免疫功能的影响。试验共设10个处理,其中n-3PUFA的来源分别为亚麻籽油和鱼油,在日粮中的添加水平分别为20、40、60和10、30、50g/kg。n-6PUFA的来源为玉米油,在日粮中的添加量为20、40和60g/kg,另设一处理为不添加脂肪酸的对照组。在试验开始后的第5周和第7周分别给每个处理组中的6只鸡注射牛血清白蛋白抗原(BSA)和绵羊红细胞(SRBC),并分别于注射后第6,10,14天和第5,9,13天翅静脉采血,测定BSA抗体效价和SRBC抗体滴度。在试验开始后的第5周和第10周,采血测定外周全血淋巴细胞增殖速度,同时每个处理杀3只鸡,取脾脏制备单核细胞,测定其增殖速度。试验结果表明,日粮中添加PUFA具有提高产蛋鸡一免及二免BSA抗体和SRBC抗体产量的趋势,并呈现剂量依赖性。其中高鱼油添加组在一免10天时能显著(P<0.05)提高SRBC抗体滴度,二免后高鱼油添加组和高亚麻籽油添加组都能够显著(P<0.10)提高SRBC抗体滴度;对于BSA抗体效价,高n-3PUFA添加组都能够显著(P<0.10)提高。产蛋鸡外周全血淋巴细胞和脾脏单核细胞增殖速度在饲喂添加高n-3PUFA日粮后受到明显抑制。鱼油来源的n-3PUFA对产蛋鸡免疫功能影响程度比亚麻籽油的大。  相似文献   
973.
The proximate properties, the fatty acid and mineral contents of different almond kernel varieties were determined. The crude protein contents of kernels ranged between 12.7% (guara) and 16.3% (cristomorto). The oil yields from these kernels were established between 48.8% (cristomorto) and 55.7% (ferragnes). The acidity value of oils were found between 1.389 and 3.559%. In addition, peroxide values were established between 7.586 (nonpareil) and 15.590 mequiv./kg (cristomorto). The major fatty acids of almond kernel oils were oleic (72.5–79.9%), linoleic (13.5–19.8%) and palmitic acids (5.9–6.7%). The predominant mineral in most kernel was potassium (13.1–15.1 mg/100 g). The mineral contents of the kernels were established as 7.94–9.38 mg/100 g potassium, 2.9–4.0 mg/100 g magnesium and 1.84–2.94 mg/100 g calcium. From the results of the present study, it can be concluded that the kernels of almond varieties are being potential sources of valuable oil which might be used for edible and other industrial applications.  相似文献   
974.
Deamidated wheat gliadins were prepared using hydrochloric acid (HCl) and citric acid (HDWG and CADWG), respectively. Their secondary structure, protein molecular interaction, thermal properties and nutritional changes were compared by Fourier transform infrared spectroscopy (FTIR), Raman spectrum, atomic force microscopy (AFM), differential scanning calorimetry (DSC), and amino acid analysis, respectively. Secondary structures and molecular vibration model showed slight difference between HDWG and CADWG, but significant difference between control gliadin and deamidated wheat gliadins. HDWG and CADWG had different shapes on the mica surface that the former showed some extent of linear aggregates and fibrils while the latter mainly exhibited globular aggregates. This result was further supported by thermal characteristics that CADWG had higher denaturation temperature than control gliadin and HDWG. Citric acid deamidation could increase the Lysine content and better maintain the total essential amino acids of in vitro digests of gliadin compared with HCl.  相似文献   
975.
综述: 植物-土壤-微生物系统中的酚酸   总被引:1,自引:0,他引:1  
Phenolic acids are very common compounds in pedosphere. The objective of this review was to summarize the current knowledge of the behaviors of phenolic acids in plant-soil-microbe system. When phenolic acids originated from leaching, decomposition and exudation of living and dead plant tissues enter soils, they can react physicochemically with soil particle surfaces and/or incorporate into humic matter. Phenolic acids desorbed from soil particle surfaces and remained in solution phase can be utilized by microbe as carbon sources and absorbed by plants. The degradation products of phenolic acids by microbe include some organic and/or inorganic compounds such as new phenolic acids. In addition, phenolic acids in soils can stimulate population and activity of microbe. Phenolic acids can inhibit plants growth by affecting ion leakage, phytohormone activity, membrane permeability, hydraulic conductivity, net nutrient uptake, and enzyme activity. Behaviors of phenolic acids in soils are influenced by other organic compounds (phenolic acids, methionine, glucose, etc.) and/or inorganic ions. The role of phenolic acids as allelopathic agents should not be neglected only based on their low specific concentrations in natural soils, because numbers and interactions of phenolic acids will increase their allelopathic activities.  相似文献   
976.
Abstract

3,3'5,5’ Tetramethyl benzidine, 3‐Amino‐9‐ethylcarbazol and chlorpromazine are suggested as alternatives for benzidine as H‐donors in the peroxidase assay for diagnosing iron deficiency in plant leaves. Procedures with these reagents, which have been used successfully with citrus and other plants, are described.  相似文献   
977.
本文通过对河北省2011份小麦育种资源及近年来区域试验和高代材料蛋白质、氨基酸的分析,看到了河北省目前小麦的营养现状;2011份材料蛋白质平均含量为13.57%,赖氨酸平均含量为0.35%.从所分析的材料来看,地区之间的蛋白质含量存在着较大的差异,廊坊地区的平均蛋白质含量一般高于其他地区.同时也可以看到由于冷凉、潮湿等因素会使小麦的蛋白质含量发生变化.指出全省应开展协作,广泛地交流材料,进一步加强对蛋白质遗传力的研究,争取早日在育种上取得突破.  相似文献   
978.
牧草叶作为饲料原料的营养价值分析   总被引:1,自引:0,他引:1  
[目的]研究旨在测定5种牧草叶片的主要营养成分,分析、评价其氨基酸的营养价值,以期为牧草叶型饲料的开发利用提供科学依据。[方法]各样品的粗蛋白、氨基酸、粗脂肪、钙、磷含量采用常规方法测定,中性洗涤纤维和酸性洗涤纤维含量采用滤袋法测定;采用必需氨基酸的氨基酸评分及化学评分评价各样品氨基酸营养价值。[结果]结果表明:(1)5种牧草叶片中CP、Ca、NDF和ADF含量的差异较大,其中CP、Ca、NDF含量差异均达到显著水平(P<0.05);水葫芦CP含量最高;2种豆科牧草叶片的CP含量显著高于禾本科牧草叶片,ADF含量则显著低于禾本科牧草叶片。(2)5种牧草叶片氨基酸种类齐全,总氨基酸、必需氨基酸含量丰富;蛋氨酸是5种牧草叶片的共同第一限制性氨基酸。[结论](1)水葫芦、紫花苜蓿、葛藤叶片的CP含量较高,可以作为蛋白饲料原料开发利用。(2)多花黑麦草和杂交狼尾草叶可以作为优质粗饲料进行开发利用。(3)利用5种牧草叶片配制牧草叶型畜禽全价饲料应适当添加蛋氨酸或补充富含蛋氨酸的原料。  相似文献   
979.
With the purpose of enhancing oil production, the present work was carried out to elucidate relationships between photosynthesis of leaves, siliques and seeds yield and seeds oil accumulation of oilseed rape. Field trials, in which two repeated experiments was carried out during 2012–2014 growth season, a rape hybrids the “Qin You No.7” (Brassica napus L.) variety was taken into account. The results showed that, on rape plant the photosynthetic capacity and chlorophyll a, b, carotenoid contents of leaf were significantly higher than that of silique shell. Oil content of 94.7% was achieved in young seeds (sampled at 25th day after flowering ending stage of the tested rape plant) versus to mature seeds, saturated fatty acids percent was higher whereas oleic acid percent was lower of oil extracted from young seeds. During flowering period of the rape plants tested, area and dry weight of leaves attained maximum, treatments of removing leaves induced reduction in seeds number per silique, siliques number, seeds yield per plant and seeds oil content, these indexes were respectively decreased by 73.6%, 43.4%, 83.4% and 10.5% in maximum, and seeds oil composition was not significantly influenced; during seeds growing period of the tested plants, surface area and dry weight of siliques attained maximum, under shading siliques treatment, the 1000-seed weight, seeds yield per plant and seeds oil content were respectively reduced by 57.5%, 61.4% and 44.7% in maximum, and seeds oil oleic acid (C18:1) and linolenic acid (C18:3) percent was decreased, linolic acid (C18:2) and erucidic acid (C22:1) percent was increased. So for oilseed rape plant during flowering period, surface area and photosynthesis of leaves dramatically influenced siliques number, seeds number and seeds yield; while in seeds growth period, surface area and photosynthesis of siliques greatly influenced 1000-seed yield, seeds yield, seeds oil content and oil composition; oil accumulation in rape seeds initiated early since seeds commencing growth, seed mature degree influenced oil composition of seeds.  相似文献   
980.
早稻氨基酸含量分析   总被引:4,自引:1,他引:4  
分析了8个早稻品种的氨基酸含量及其组成。结果表明,在供试材料中,各种氨基酸含量高低顺序基本相似,都以谷氨酸最高;只有谷优150的丝氨酸与其它品种间差异显著;优Ⅰ316的亮氨酸与其它品种间差异极显著。赖氨酸和苏氨酸作为限制性氨基酸,在各品种间的差异并不显著。各种类氨基酸在8个供试材料组合差别不大。  相似文献   
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