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1.
为准确测定出油菜中维生素C的含量，在国标基础上，建立了一种高效、准确测定新鲜油菜维生素C含量
的方法。结果表明：维生素C在测定范围内峰面积与标准液浓度线性关系良好，相关系数为0.9999。油菜维生素C
含量测定的回收率为97.97%~101.40%，相对标准偏差RSD仅为1.84%，说明用该方法重现性良好，具有快速准确、
稳定可靠等特点。贮藏温度越低，维生素C降解的速度越慢，用液氮贮藏样品更有利于维生素C的保存和精准鉴
定；利用液氮冷冻并研磨样品更有利于样品中维生素C的提取，测得油菜中维生素C含量与仅均质化处理相比平均
增加了约16%；液氮中贮藏的样品在不同时间下测定其维生素C含量并无显著变化，测得维生素C含量的RSD均小
于2%。利用此方法可以测定较长时间保存样品中的维生素C，可满足高通量、高准确率的要求，有利于油菜的菜用
营养和育种研究。 相似文献
2.
龙脑樟为目前国内提取天然冰片效益最高的植物，为助力其道地产区的确定，本研究根据龙脑樟的习性，拟选取国内8个产地的龙脑樟枝叶为材料，采用水蒸汽蒸馏法分别提取天然冰片；通过气质联用法（GC-MS）测定其中化学成分的相对含量；通过纸片法测定其对大肠杆菌、伤寒沙门氏菌以及肠炎沙门氏菌的抑菌圈直径；运用96微量孔板测定最小抑菌浓度（MIC）和最小杀菌浓度（MBC）。结果表明：各个产地龙脑樟枝叶提取的天然冰片中化合物含量具有差异性，其中以右旋龙脑、樟脑、d-柠檬烯、α-葎草烯、4-萜烯醇、桉叶油醇、莰烯以及d-α-蒎烯等为共有成分，且以右旋龙脑含量最高，樟脑次之，各产地中以湖北远安的右旋龙脑含量最高（82.47%），以广东乳源的右旋龙脑含量最低（41.63%）；各个产地提取的天然冰片对3个供试菌种均有一定抑菌作用，且抑菌圈直径范围为14.60～27.95 mm；最低抑菌浓度（MIC）范围为250～1250μg/mL；最低杀菌浓度（MBC）范围为0～1000μg/mL，总体以湖北远安和江西吉水的综合抑菌效果最佳，广东乳源最差。由此可见，右旋龙脑含量最高的产地抑菌效果最佳，反之抑菌效果欠佳，因此，龙脑... 相似文献
3.
乌龙茶对人体血、尿中维生素C含量的影响 总被引：2，自引：0，他引：2
维生素C对人体健康的重要性已为人们所重视。它在鲜茶叶和新绿茶中的含量与肝脏和柠檬相仿,在陈旧绿茶与红茶中的含量已大为下降。饮茶者直接从茶中获得的维生素C估计每天仅约几mg。约合人体需要量的十分之一。但是,茶叶含有复杂的多酚类物质,包括维生素P,对机体利用维生素C有着重要作用。1959年Erofeeva N.N.和ShamraiE.F.等分别在豚鼠上证明维生素P或从果子提取的多酚类物质都有显著增加动物肝、肾、脾等组织中维生素C含量的作用。王氏介绍以1mg茶叶单宁喂给每天吃维生素C10mg的大白鼠45天,使其多种内脏和肌肉中维生素C的 相似文献
4.
为了对香蕉果实中水溶性维生素的营养质量有更直观的了解,对不同产区（海南、云南、福建、广东、广西5个主产区）和不同种（香蕉、大蕉、皇帝蕉、粉蕉、红香蕉5个种）香蕉果实中维生素B2（VB2）、维生素B6（VB6）及叶酸3种水溶性维生素含量的差异进行比较。分析水溶性VB2、VB6及叶酸含量,比较其产地间差异和种间差异,并与其他4种热带水果进行比较。结果表明：香蕉果实中VB2、VB6、叶酸含量分别为0.058、0.338、0.010 mg/100 g,其中以VB6含量最为丰富;不同产地间香蕉果实中VB6和叶酸含量差异明显,VB2含量差异不显著;不同种香蕉果实中,以皇帝蕉果实中VB2、VB6和叶酸含量最高。与其他4种热带水果进行比较发现,香蕉果实中水溶性VB6的含量最为丰富,是芒果的2.6倍,荔枝的1.7倍。可见,香蕉果实中含有丰富的VB6,其INQ值为5.60,完全能满足人体日常推荐摄入量,可作为人体补充VB6的良好来源。 相似文献
5.
采用Box-Behnken响应面试验设计法对玫瑰茄总黄酮超声波-微波协同提取工艺进行优化,研究了乙醇浓度、液固比、提取时间、微波功率、提取次数5个单因素对总黄酮提取量的影响,建立了乙醇浓度、液固比和微波功率的三因素回归模型,并研究其抗氧化活性。结果表明,提取的最佳工艺参数为乙醇浓度40%、液固比50∶1（mL/g）、微波功率250 W、提取时间20 min、超声波功率50 W,在此条件下提取2次,总黄酮提取量为40.2 mg/g。同时以维生素C作对照,研究了玫瑰茄总黄酮粗提物和纯化物的体外抗氧化活性。结果表明,玫瑰茄总黄酮粗提物和纯化物都具有较强的抗氧化活性,能够有效清除O2-?自由基和DPPH自由基,清除能力与浓度呈较明显的量效关系,但抗氧化能力较维生素C弱。 相似文献
6.
为准确测定反式维生素K1的含量，建立了基于固相萃取-高效液相色谱串联质谱的甘蓝型油菜（Brassica napus L.）菜薹反式维生素K1高灵敏检测技术。样品经正己烷提取、中性氧化铝柱净化后，用C30反相色谱柱，以甲醇 （含0.025%甲酸+2.5 mmol/L甲酸铵）为流动相，采用选择反应监测（selected reaction monitoring, SRM）模式进行定量分析，20 min内可实现顺反异构体色谱分离。方法学考察结果显示，反式维生素K1在范围内线性关系良好，相关系数为0.9985。该方法检出限为0.29 μg/kg，定量限为0.95 μg/kg。回收率为87.5%～117.6%，精密度（RSD）在0.72% ～9.59%之间。利用该方法对油菜薹和反式维生素K1含量高的3种蔬菜进行分析，发现油菜薹中反式维生素K1含量为340.08 μg/100g，高于小白菜（B. rapa spp. chinensis，260.93 μg/100g）、西兰花（B. oleracea var. Italic Planch， 167.65 μg/100g）和结球甘蓝（B. oleracea var. capitata，151.11 μg/100g）。本文建立的蔬菜中反式维生素K1准确定量分析方法操作简单、灵敏度高、结果准确。同时比较发现油菜薹是一种富含维生素K1的蔬菜。 相似文献
7.
《中国马铃薯》2021,(3)
为研究不同产地与不同品种对马铃薯品质的影响,对7个不同马铃薯品种在甘肃省具有代表性的旱作农业县(区)(古浪县直滩乡、安定区香泉镇、渭源县会川镇、庄浪县通化乡和环县甜水镇)进行多点试验。方差分析结果显示,品种和产地因素极显著影响马铃薯块茎干物质含量、粗蛋白含量,品种×产地互作对马铃薯块茎干物质含量影响极显著,对粗蛋白含量的影响不显著;马铃薯块茎粗淀粉含量、维生素C含量受品种因素影响显著,产地因素和品种×产地互作效应对其影响不显著;产地因素显著影响马铃薯块茎中K含量、极显著影响Ca含量、Se含量,品种因素和品种×产地互作对马铃薯块茎中K含量、Ca含量、Se含量影响不显著;马铃薯块茎中Zn含量受产地因素影响极显著,品种对马铃薯块茎中Zn含量的影响显著,品种×产地互作效应对马铃薯块茎中Zn含量的影响不显著。研究结果可为提升马铃薯营养品质提供参考。 相似文献
8.
利用高效液相色谱法分析了11个菠萝品种果实中5种维生素含量的差异。结果表明,在11个品种果实中,维生素C含量在99.9~230.9μg/g,维生素A含量在1.6~3.8μg/g,维生素B3含量在3.8~23.5μg/g,维生素B6含量差异较大,在4.5~67.1μg/g,巴厘、台农11号、Golden Winter Sweet、New Phuket、Phuket 5个品种中未检测到含有维生素B12,其它品种维生素B12含量在2.0~12.1μg/g。巴厘维生素A含量显著高于其它品种,台农11号维生素C含量显著高于其它品种,Golden Winter Sweet维生素B3和维生素B6含量最高,台农19号维生素B12含量最高。 相似文献
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Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献
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Lakshman Lal 《Potato Research》1987,30(2):329-334
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
14.
《Journal of Crop Improvement》2013,27(2):81-114
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
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Tatiana G. Polotow Sandra C. Poppe Cristina V. Vardaris Douglas Ganini Maísa Guariroba Rita Mattei Elaine Hatanaka Maria F. Martins Eduardo F. Bondan Marcelo P. Barros 《Marine drugs》2015,13(10):6117-6137
Health authorities worldwide have consistently recommended the regular consumption of marine fishes and seafood to preserve memory, sustain cognitive functions, and prevent neurodegenerative processes in humans. Shrimp, crabs, lobster, and salmon are of particular interest in the human diet due to their substantial provision of omega-3 fatty acids (n-3/PUFAs) and the antioxidant carotenoid astaxanthin (ASTA). However, the optimal ratio between these nutraceuticals in natural sources is apparently the key factor for maximum protection against most neuro-motor disorders. Therefore, we aimed here to investigate the effects of a long-term supplementation with (n-3)/PUFAs-rich fish oil, ASTA-rich algal biomass, the combination of them, or krill oil (a natural combination of both nutrients) on baseline redox balance and neuro-inflammation indexes in cerebellum and motor cortex of Wistar rats. Significant changes in redox metabolism were only observed upon ASTA supplementation, which reinforce its antioxidant properties with a putative mitochondrial-centered action in rat brain. Krill oil imposed mild astrocyte activation in motor cortex of Wistar rats, although no redox or inflammatory index was concomitantly altered. In summary, there is no experimental evidence that krill oil, fish oil, oralgal biomass (minor variation), drastically change the baseline oxidative conditions or the neuro-inflammatory scenario in neuromotor-associated rat brain regions. 相似文献
17.
Youna Hemery Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Tanja Nurmi Vieno Piironen Minnamari Edelmann Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is a composite material made of several layers, such as pericarp, testa and aleurone. It could be fractionated into purified fractions, which might either be used as food ingredients, or serve as a starting material for extraction of bioactive compounds. The aim of this work was to evaluate the potential of using electrostatic separation as a way to obtain purified fractions from wheat bran. Ultrafine-ground bran obtained either by cryogenic grinding or by grinding at ambient temperature was used as starting material. The ultrafine bran was then charged by tribo-electrification and introduced in a chamber containing two high voltage electrodes, where bran particles were separated depending on their acquired charge, allowing positively and negatively charged fractions to be collected separately. The particle size distribution, microstructure and biochemical composition of the obtained fractions were studied. The charge of the particles was influenced by their biochemical composition: particles rich in highly branched and cross-linked arabinoxylans (pericarp) were separated from particles rich in β-glucan, ferulic acid and para-coumaric acid (aleurone cell walls). The testa and the intracellular compounds from aleurone were not highly charged, neither positively nor negatively. The most positively charged fraction represented 34% of the initial bran, and contained 62% of the ferulic acid present in the initial bran. The yield of the separation process was good (5.4% loss), and could be further increased. 相似文献
18.
Alexander N. Shikov Elena V. Flisyuk Ekaterina D. Obluchinskaya Olga N. Pozharitskaya 《Marine drugs》2020,18(11)
Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future. 相似文献
19.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
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
20.
Tovar LR Olivos M Gutierrez ME 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(4):189-194
Pulque is made by fermenting the agave sap or aguamiel of Agave atrovirens with a whole array of microorganisms present in the environment including several lactic acid bacteria and yeasts such as
Saccharomyces cerevisiae. Ascorbic acid was determined in pulque and aguamiel, respectively. Phytase activity in lees, liquid and freeze-dried pulque was assayed by measuring the appearance of phosphate from phytate by a colorimetric method likewise phosphate from phytate
present in fresh corn tortilla was measured after in vitro incubation with pulque. Iron, zinc, calcium, magnesium and selenium contents were measured in pulque and corn tortilla as well as in nixtamalized corn flour (NCF), the latter is used to make instant tortilla, since corn provides
most of the energy as well as most of the phytate in the Mexican rural diet. Pulque showed phytase activity but much less ascorbic acid and iron than previously reported; additionally, phytase in pulque hydrolyzed most of phytate’s corn tortilla. Lees, which is mostly made of pulque’s microbiota, significantly accumulated iron and zinc but no selenium. NCF was fortified with iron by the manufacturers but
poorly blended. There were significant differences on selenium content between tortillas samples, apparently some soils in
central Mexico are selenium deficient. Moderate pulque intake appears to increase the bioavailability of iron and zinc bound by phytate in corn. 相似文献