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1.
水稻籽粒不同部位植酸含量及其与稻米品质的相关性   总被引:1,自引:0,他引:1  
 选用13个不同类型的水稻品种,对其籽粒不同部位植酸含量品种间差异及与稻米主要品质性状间的相关性进行了分析。结果表明,供试13个水稻品种米糠、糙米、颖壳、精米的植酸含量平均值分别为48.51、9.77、1.40和0.91 mg/g,而且不同水稻品种间籽粒不同部位的植酸含量存在极显著差异。在籽粒中,米糠中植酸积累最多,其次是精米,颖壳最少。米糠中植酸含量与糙米和颖壳中植酸含量呈极显著正相关。糙米和米糠中植酸含量与稻米蛋白质含量均呈显著的负相关,与千粒重均呈显著正相关。  相似文献   

2.
植酸是植物中磷的主要储存形式,适当减少植酸含量就可以提高作物种子中微量元素的利用率、降低环境中磷的污染和浪费。本研究旨在通过钼蓝显色法测定小麦种子中无机磷的含量,间接反映小麦品种(品系或株系)的植酸含量,从而为低植酸小麦品种的培育提供参考。对348个普通小麦品种(系)、232个近缘种杂交后代株系,以及4个普通小麦杂交组合的第四代(或第五代)株系进行了无机磷含量测定,结果表明,这570份小麦材料的籽粒无机磷含量主要分布在0.46μg/mg-0.93μg/mg之间,低无机磷(低于0.15μg/mg)、高无机磷(高于0.93μg/mg)的材料比较少,呈现中间多、两头少的分布趋势。4个杂交组合群体无机磷含量的平均值分别是0.6549μg/mg、0.5918μg/mg、0.4538μg/mg和0.5792μg/mg,没有高无机磷或者低无机磷含量的株系,可能由这4个组合的亲本无机磷含量所决定的。因此,在普通小麦品种(系)、近缘种杂交后代株系中存在少量高无机磷和低无机磷的材料,而从中等无机磷含量的亲本杂交后代中没有筛选到高无机磷(低植酸)的株系。  相似文献   

3.
以钝化新鲜全脂米糠为原料,通过复合酶酶解钝化新鲜全脂米糠,分离提取稻米油后,再用糖化酶解底物,制得了米糠蛋白多肽。以钝化新鲜全脂米糠为底物,在50℃pH 6.0的条件下添加2.0%碱性蛋白酶、纤维素酶组成的复合酶(1:1,w/w)酶解5 h,稻米油的提油率为23.27%,稻米油中γ-谷维素1 411±11.26 mg/100 g。将米糠酶解物溶液pH调至3.5,加0.3%的糖化酶,酶解温度60℃,酶解1.5 h,当DH为21.04%,蛋白质回收率为80.13%,米糠蛋白多肽中蛋白质含量为81.3%;肽含量71.1%,小于2 000 Da分子量的组分占83.15%。  相似文献   

4.
为筛选高白藜芦醇含量的花生品种,采用超声萃取法提取、高效液相色谱法测定白藜芦醇含量,对28个花生品种不同营养器官中白藜芦醇含量进行了分析.结果表明,不同花生品种不同营养器官中白藜芦醇含量差异较大,所有品种根部、茎部和叶片中白藜芦醇的平均含量分别为0.276 mg/g、0.173 mg/g和0.098 mg/g,白藜芦醇...  相似文献   

5.
以受黄曲霉毒素B_1(aflatoxin B_1,AFB_1)污染的米糠为原料,研究微波辅助酶法对米糠中AFB_1脱除效果的影响。初始米糠中AFB_1浓度为102.54μg/kg,以料液比(g∶m L)1∶10、加酶量0.50%、α-淀粉酶和纤维素酶酶解液pH6.0、温度50℃、处理时间2 h的工艺条件制备米糠蛋白。结果表明,米糠中AFB_1残留浓度为56.03μg/kg(脱除率为45.36%),米糠中蛋白质回收率为78.20%;基于该工艺研究,在单位体积微波功率750 W和处理时间10 min的条件下,由酶法提取的米糠蛋白制品中AFB_1残留浓度为4.21μg/kg(脱除率为92.48%),符合国家标准(≤10μg/kg),而蛋白质回收率达到81.36%。本研究采用免疫亲和柱净化结合HPLC-FLD检测法,提高AFB_1的检出限至0.10μg/kg。微波处理不仅对米糠蛋白中AFB_1有明显的脱除效果,且有利于蛋白回收率的提高。该法操作简单,脱除效率高,可应用于受黄曲霉毒素污染的米糠制品中。  相似文献   

6.
为了分析香水莲花的植物甾醇含量并优化其超声提取工艺,采用高效液相色谱(HPLC)法测定香水莲花中菜籽甾醇、菜油甾醇和β-谷甾醇的含量,再以上述3种甾醇提取量为评价指标,对液料比、超声提取温度和超声提取时间进行单因素试验,在此基础上,再采用Box-Behnken响应面法优化香水莲花甾醇提取工艺并进行验证。结果表明,影响香水莲花甾醇提取量的主次因素是液料比>提取时间>提取温度,其最优工艺条件为以95%乙醇为提取溶剂、超声功率100 W、液料比30∶1(mL/g)、超声提取温度60 ℃、超声提取时间30 min;在最优工艺条件下进行验证实验,得出香水莲花中甾醇含量为菜籽甾醇64.61 mg/100 g、菜油甾醇40.77 mg/100 g、β-谷甾醇99.04 mg/100 g,总甾醇204.42 mg/100 g,综合评分与预测值相比差异不显著(P<0.05)。研究结果为香水莲花资源的开发和利用提供参考。  相似文献   

7.
为充分利用暴马丁香,以暴马丁香叶为材料,利用超声辅助提取法对暴马丁香叶的径粒大小、液料比、乙醇浓度、超声时间进行了研究。结果表明:径粒大小为过80目筛时,提取暴马丁香总黄酮含量最高为11.078mg/g,液料比为1∶15时暴马丁香总黄酮提取含量最高为23.653mg/g,乙醇浓度为70%时暴马丁香总黄酮提取含量最高为26.116mg/g,超声时间为20min时暴马丁香总黄酮提取含量高为26.158mg/g,正交实验优化得到的最佳工艺条件为径粒大小为60目,液料比为1∶15,乙醇浓度为80%,超声时间为40min。  相似文献   

8.
为探究甘肃酒泉产甜叶菊中总黄酮提取条件、成分与其抗氧化活性间的关系。采用乙醇超声水浴提取法,探讨提取时间、温度、料液比、功率等因素对总黄酮提取条件的影响;用HPLC柠檬酸-甲醇流动相梯度洗脱法测定甜叶菊中芦丁、圣草枸杞苷、山奈素、槲皮素、橙皮苷的含量;用FRPD和DPPH法评价甜叶菊茎叶中总黄酮提取物与抗氧化活性之间的关系。结果:通过正交试验,得出乙醇超声水浴的最佳提取条件:80%乙醇、提取功率450 W、料液比1∶20、提取时间150 min、温度85℃、提取3次,总黄酮提取率最高可达到0.88%;HPLC法检测甜叶菊茎叶中5种黄酮成分,以芦丁的含量(701.42μg/g)为最高,槲皮素含量(451.55μg/g)居其次,橙皮苷含量(297.54μg/g)与山奈素含量(241.21μg/g)较少,圣草枸杞苷含量(57.44μg/g)极微;用FRPD和DPPH法评价甜叶菊茎叶总黄酮提取物抗氧化活性,其抗氧化活性高达10.02 mg/g DW,黄酮含量与抗氧化活性二者呈较显著的正相关性(R=0.769~0.792)。这为甜叶菊中黄酮类物质的提取与进一步开发利用提供基础性研究资料。  相似文献   

9.
红茶主要多酚类化合物的HPLC分析   总被引:1,自引:0,他引:1  
以正山小种、坦洋工夫等16种不同产地的典型红茶为供试材料,采用HPLC法分析比较了红茶中主要多酚类物质含量的差异.结果表明,红茶主要多酚类物质含量差异较大,其中儿茶素总量、没食子酸、绿原酸、黄酮醇及其苷类物质的含量分别为4.50-41.65mg/g,1.139 ~ 3.689mg/g,0~ 530mg/kg,0.63 ~ 4.48mg/g,苏红工夫、海南红茶、台湾红茶、越红工夫中的酯型儿茶素较高;英德红茶、台湾红茶中的黄酮醇类物质含量较高;正山小种的多酚类物质含量较低,且种类少.槲皮素、杨梅素苷类物质仅在部分样品中有检出,含量分别不高于3.00mg/g和1.50mg/g,芹菜素未被检测出.根据红茶中主要多酚类化合物含量的差异将16种红茶划分为3个类群.  相似文献   

10.
黄淮地区小麦旗叶主要光合色素含量及光谱吸收   总被引:1,自引:1,他引:1  
用丙酮提取后,用日产岛津UV-160分光光度计在4年间测定了黄淮区85个普通小麦品种(系)旗叶中的叶绿素含量。叶绿素a含量为2.444~2.871 mg/g鲜叶,均约2.753 mg/g鲜叶(σ=0.093,n=163,下同);叶绿素b含量为0.875~1.688 mg/g鲜叶,均约1.253 mg/g鲜叶(σ=0.149);叶绿素a+b为3.340~4.516 mg/g鲜叶,均约4.028 mg/g鲜叶(σ=0.231);b/a为0.355~0.588,均约0.453(σ=0.0795)。小麦旗叶离体叶绿素均在662~663 nm、431~455 nm及327~378 nm处出现吸收高峰。豫麦13的a+b含量最高,且其光吸收峰谱表现明显的倾母遗传趋势。  相似文献   

11.
12.
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.  相似文献   

13.
Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.  相似文献   

14.
15.
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.  相似文献   

16.
Novel food and non-food uses for sorghum and millets   总被引:4,自引:3,他引:4  
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.  相似文献   

17.
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact).  相似文献   

18.
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.  相似文献   

19.
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.  相似文献   

20.
Chitosan is considered to be one of the most promising and applicable materials in adsorption applications. The existence of amino and hydroxyl groups in its molecules contributes to many possible adsorption interactions between chitosan and pollutants (dyes, metals, ions, phenols, pharmaceuticals/drugs, pesticides, herbicides, etc.). These functional groups can help in establishing positions for modification. Based on the learning from previously published works in literature, researchers have achieved a modification of chitosan with a number of different functional groups. This work summarizes the published works of the last three years (2012–2014) regarding the modification reactions of chitosans (grafting, cross-linking, etc.) and their application to adsorption of different environmental pollutants (in liquid-phase).  相似文献   

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