In Vitro Bile Acid Binding Capacity of Wheat Bran with Different Particle Sizes

The bile acid binding capacity of wheat bran with different particle sizes was determined. Unmilled wheat bran with an average particle size of 900 μm (WB‐900), milled wheat bran at two particle sizes, 500 and 200 μm (WB‐500 and WB‐200), and all three bran samples washed with water (WWB‐900, WWB‐500, and WWB‐200) were mixed with bile acids at pH 6.3 to determine their in vitro adsorption capacity. On a dry matter basis, the order of relative bile acid binding values was WB‐900 ∼ WB‐500 > WWB‐900 > WB‐200 > WWB‐500 > WWB‐200. Data suggests that the surface area as measured by the Brunauer–Emmett–Teller (BET) method and water holding capacity may significantly affect the bile acid binding capacity of wheat bran. As the BET surface area increased with decreasing particle size, the water holding capacity and bile acid binding decreased. Bile acid binding capacity of wheat bran appears to be linked to the ability of the samples to physically adsorb the bile acids. Bile acid binding capacity significantly decreased with reduction in particle size of wheat bran after water washing.     

酸雨胁迫对大豆萌发种子糖代谢动态的影响

为了探索酸雨胁迫对大豆萌发种子糖代谢动态的影响,试验采用蒸馏水浸泡大豆种子,再以pH2.5、4.5模拟酸雨(AR)处理大豆种子,考察不同强度AR胁迫对大豆萌发种子可溶性糖、还原性糖、蔗糖、淀粉及α、β-淀粉酶含量的影响。结果表明,第1天AR组的可溶性糖含量上升,第2天明显降低,随后稳定降低;AR胁迫下的第1天-第4天,还原糖含量维持较高水平,第3天-第5天呈下降趋势;pH2.5组在第2天-第5天蔗糖含量减少;AR胁迫的第2天-第4天淀粉含量降低;总体上,AR组的α-淀粉酶活性CK,但从第5天起pH2.5组的α-淀粉酶活性CK;β-淀粉酶活性在第1天-第6天高于或接近CK,pH2.5组在第7天低于CK。糖代谢各项指标和淀粉酶活性之间的关系表明,可溶性糖、还原糖、蔗糖含量变化幅度随AR胁迫强度增大而增加,淀粉含量变化与之相反;AR组对淀粉酶活性影响是导致萌发改变的内在因素之一。     

Dehydrotriferulic and Dehydrodiferulic Acid Profiles of Cereal and Pseudocereal Flours

Dehydrooligomers of ferulic acid cross‐link polysaccharides such as arabinoxylans and pectic polysaccharides in cereal and certain pseudocereal grains, affecting physiological effects of these fiber components and their physicochemical properties during food processing. An HPLC‐MS method for the analysis of eight diferulic acids and five triferulic acids in low‐lignin samples such as cereal grains and pseudocereals was developed and validated. This method was applied to the analysis of ester‐linked diferulates and triferulates in maize, popcorn, wheat, rye, oats, barley, buckwheat, and amaranth, giving a complete profile of this set of diferulates and triferulates in cereals and pseudocereals. Triferulic acid contents of the cereal flours are roughly 1/10 of the diferulic acid contents, ranging between 23 (oats) and 161 (popcorn) μg/g of flour, with lower amounts for the pseudocereal flours (1–3 μg/g of flour). Dominating trimers are either the 5‐5/8‐O‐4‐ and/or the 8‐O‐4/8‐O‐4‐regioisomers with lower proportions of 8‐8cyclic/8‐O‐4‐, 8‐5noncyclic/8‐O‐4‐, and 8‐5noncyclic/5‐5‐triferulic acids. A unique diferulate pattern was found for buckwheat, with more than 90% of the dimers being 8‐5‐coupled. Amaranth contains an unusually high proportion of 8‐8cyclic‐diferulate, with 27% of the total dimers, whereas oats and barley show comparably high proportions (23%) of the 8‐8tetrahydrofuran diferulate.     

IBA和NAA不同浓度复配对金丝皇菊扦插生根的影响

为研究金丝皇菊枝条扦插生根基质中添加生长激素IBA和NAA促进生根的最佳复配浓度和浸泡时间。设置IBA 0、200、400、600 mg/L,NAA 0、100、200、300 mg/L,浸泡时间0.5、1.0、1.5、2.0 h的L16(43)三因素四水平正交试验。结果表明IBA和NAA单用时,金丝皇菊枝条扦插的平均根系效果指数分别为2.28和1.53。IBA 200 mg/L和NAA 200 mg/L复配液浸泡金丝皇菊枝条2.0 h,其根系效果指数为3.90,生根效果最好;IBA 600 mg/L、NAA300 mg/L复配液浸泡金丝皇菊0.5 h,对生根有一定的抑制作用,其他处理较清水浸泡0.5 h对生根均有一定的促进作用。IBA 200 mg/L和NAA 200 mg/L复配,浸泡2 h,为最佳复配浓度和浸泡时间,过大的复配浓度对生根有抑制作用。     

Acute toxicity of high doses of the glycoalkaloids, alpha-solanine and alpha-chaconine, in the Syrian Golden hamster

Sprouted, stressed, or spoiled potato tubers have reportedly led to human acute intoxication, coma, and death when consumed in high amounts. These effects have been attributed to glycoalkaloids (GAs), primarily alpha-solanine and alpha-chaconine, naturally present in all potatoes. The level of GAs in potato tubers has previously been shown to increase substantially as a result of improper handling and postharvest storage. A short-term study was performed to investigate the dose-response profile of alpha-solanine and alpha-chaconine alone or in combination, administered daily by oral gavage to Syrian Golden hamsters. Daily doses of 100 mg of alpha-solanine [kg body weight (BW)] (-1) induced death in two of four hamsters within 4 days, when administered by gavage to female Syrian hamsters. Doses of 100 mg of alpha-chaconine alone or alpha-solanine and alpha-chaconine combined in a ratio of 1:2.5, in doses of 75 or 100 mg (kg BW) (-1), induced death in one of four hamsters within the same period. Animals dosed with alpha-solanine alone or in combination with alpha-chaconine suffered from fluid-filled and dilated small intestines. The GA administration had no effect on acetyl cholinesterase (AChE) or butyryl cholinesterase (BuChE) activity in plasma or brain. Liquid chromatography-mass spectrometry-based metabolomics showed that there was a specific accumulation of alpha-chaconine in the liver tissues. In addition, metabolomics gave direct evidence of glycolytic metabolism of the GA with the beta 1, beta 2, and gamma-GAs detected in the urine and, to a lesser extent, the feces. Doses from 75 mg (kg BW) (-1) of alpha-chaconine, alpha-solanine, or the two compounds combined were potentially lethal within 4-5 days in the Syrian Golden hamster. However, the cause of death in these studies could not be established. No synergistic effects of alpha-solanine combined with alpha-chaconine were evident.     

Development and Application of a Methodology to Determine Free Ferulic Acid and Ferulic Acid Ester‐Linked to Different Types of Carbohydrates in Cereal Products

Ferulic acid bioavailability is dependent on its form present in food. This necessitates a methodology to quantify different groups of ferulic acid derivatives in food products, especially cereal‐based products. The aim of the proposed methodology is to separate and quantify ferulic acid ester‐linked to mono‐ and/or oligosaccharides (OF), to soluble polysaccharides (SPF), and to insoluble polysaccharides (IPF) as well as in its free form. Development and partial validation of this method, which was widely based on liquid/liquid extraction and precipitation steps, was performed using characterized standard materials isolated from corn bran. As the determination of OF was one of the major goals of this methodology, three different feruloylated mono‐ and oligosaccharides were used for method development and validation. To determine the accuracy of the method, ferulic acid–containing standard materials added to a starch matrix were extracted and separated according to the developed protocol. The separated ferulic acid esters were saponified before ferulic acid was analyzed by reversed phase HPLC. Recovery rates were generally between 70 and 103%, with the lowest recovery rates for SPF and highest recovery rates for IPF and OF. Finally, the applicability of the method to unprocessed and processed wheat bran samples was demonstrated.     

Physiological Effects of Different Combinations of Humic and Fulvic Acid on Gerbera

Flower quality loss, especially short postharvest life, is a major problem in gerbera production. An experiment was conducted to determine how different combinations of humic substances (HS) affect gerbera. Humic acid (HA) and fulvic acid (FA) applied to nutrient solutions in six combinations including control (nutrient solution only), 80 mg L^?1 HA + 20 mg L^?1 FA, 60 mg L^?1 HA + 40 mg L^?1 FA, 40 mg L^?1 HA + 60 mg L^?1 FA, 100 mg L^?1 FA, and 50 mg L^?1 FA. The HS application enhanced root architecture, nutrient content, number of harvested flowers, and vase life. Fifty (50) mg L^?1 FA extended vase life by 8 days and increased flower number (72.9%). Results suggest that HA and FA (especially 50 mg L^?1 FA) can improve quality and quantity of gerbera through improving root architecture, leading to enhanced nutrient uptake and possibly affecting hormone-like activities. It seems that using low concentrations of FA may be part of a solution in improving gerbera flower quality.     

不同基质配比对戈壁温室黄瓜生理代谢和产量及品质的影响

基质是黄瓜生长的基础,对其产量品质影响巨大,为得到戈壁温室有机生态型无土栽培中高品质黄瓜生产的最适基质配比,以当前生产中常用基质配比为对照,研究了5种不同配方的基质对黄瓜叶片叶绿素荧光参数及产量品质影响,并比较了不同处理下黄瓜生长生理及产量品质指标。结果表明,采用配方为腐熟牛粪、粉碎玉米秸秆、菌渣、草炭、蛭石体积比为3∶2∶2∶2∶1的基质栽培时,黄瓜叶片最大量子产额(Fv/Fm)与生长潜在活性(Fv/Fo)的值最大,分别为0.76、3.18;黄瓜株高196.15 cm、茎粗0.92 cm、叶片数38.31片、单株结瓜数17.65个、单株产量3.58 kg、折合产量155 508.90 kg/hm2,均高于其他处理。采用该基质配比时黄瓜果实的Vc含量与可溶性糖含量均最高,分别为167.28、19.83 mg/g FW;硝酸盐含量最低,为78.94 μg/g FW。可见,使用腐熟牛粪、粉碎玉米秸秆、菌渣、草炭、蛭石体积比为3 ∶ 2 ∶ 2 ∶ 2 ∶ 1的基质配方时黄瓜综合表现最佳,产量及品质最优。     

不同施肥结构对酸性黄棕壤修复效果研究

利用3年田间定位试验,研究了不同施肥结构对酸性黄棕壤酸性、交换性能以及微生物区系的影响。结果表明:连年施用有机肥以及配施石灰和白云石粉均能显著降低土壤中交换性酸和交换性Al~(3+)的含量,提高土壤pH,且不同施肥结构对修复黄棕壤酸性的效果为有机肥配施石灰有机肥配施白云石粉有机肥;连年施用有机肥以及配施石灰主要提高了土壤中交换性Ca~(2+)含量,而配施白云石粉则主要提高了土壤中交换性Mg~(2+)含量;有机肥配施石灰和白云石粉均降低了土壤中真菌的数量,但提高了土壤中细菌/真菌比、放线菌/真菌比以及细菌和放线菌数量,改善了土壤微生物群落结构,增加了烟叶的产量和产值。     

Nutritional Effect of Flaxseeds on Cholesterol Profile and Fatty Acid Composition in Egg Yolk

This experiment investigated the effect of a supplementary dietary source (flaxseed) on egg yolk cholesterol contents and fatty acid profile. Flaxseeds at three different levels (5, 10, and 15%) were supplemented to 84 Rhode Island Red × Fayoumi cross layers during 21–24 weeks of age. The birds were divided randomly into four groups. Flaxseeds were supplemented in the diet at the level of 5% (FS‐5), 10% (FS‐10), and 15% (FS‐15), and one group served as the control (FS‐0). Cholesterol content of eggs was not significantly affected by flaxseed. The amount of monounsaturated fatty acids was significantly decreased with the increase in the flaxseed level, and the highest reduction was observed in FS‐15. The highest total polyunsaturated fatty acid (PUFA) and total omega‐3 PUFA were recorded in FS‐15. These findings reflect that unsaturated healthy fatty acid content in poultry eggs can be increased with dietary supplementation of flaxseed.     

不同电解质对牛粪生物质炭中腐殖酸吸附–解吸的影响

本文研究了NaCl、Na_2SO_4、Na_3PO_4 3种背景电解质对牛粪生物质炭中腐殖酸吸附和解吸的影响。结果表明:在这3种背景电解质作用下,牛粪生物质炭对腐殖酸的吸附量和吸附率随着加入液腐殖酸浓度的增加而增加,但是增加速度逐渐变缓。3种背景电解质相比,NaCl中牛粪生物质炭对腐殖酸的吸附量和吸附率均为最高,吸附量范围为0.13～6.10 mg/g,吸附率范围为25.40%～87.14%。随着加入液腐殖酸浓度的增加,吸附态腐殖酸的解吸量逐渐增加,解吸率逐渐减小。3种背景电解质相比,Na_2SO_4中牛粪生物质炭吸附的腐殖酸的解吸量最高,解吸量范围为0.15～0.78 mg/g。加入液腐殖酸浓度为140 mg/L,3种背景电解质中牛粪生物质炭吸附的腐殖酸的解吸量均达到最大值,解吸量的大小顺序为Na_2SO_4Na_3PO_4NaCl。Na_3PO_4对腐殖酸的解吸率影响最大,解吸率范围为17.24%～90.55%,NaCl对腐殖酸的解吸率影响最小,解吸率范围为8.22%～53.54%。用Langmuir拟合3种背景电解质中腐殖酸的等温吸附曲线和等温解吸曲线,其相关系数都达到显著水平。研究结果揭示了不同背景电解质对牛粪生物质炭吸附和解吸腐殖酸的影响,可为土壤保土保肥提供理论参考。     

不同处理对海沃德猕猴桃内源ABA相关代谢基因表达的影响

为在分子水平阐明外源乙烯利、1-MCP和ABA处理对海沃德猕猴桃内源ABA合成代谢的影响,并揭示ABA调控果实后熟机理。本研究以海沃德猕猴桃果实为试验材料,利用外源乙烯利、1-MCP和ABA处理猕猴桃果实,分别运用高相液相色谱(HPLC)和RT-qPCR分析20℃贮存条件下对猕猴桃内源ABA合成、信号通路相关基因XanDH、PYR/PYL、PP2C、ABF的表达量影响。结果表明,乙烯利处理下PP2C和ABF基因表达量在DAH17~DAH58都显著低于对照组,XanDH和PYR/PYL在DAH17均显著高于对照组,而后迅速回落。在ABA处理下XanDH基因表达量呈先下降后上升再下降的趋势,在DAH17表达量最高。PP2C和PYR/PYL在DAH17经历高峰后逐渐回落至低水平,与对照组差异显著。ABF在采后前期有较高的表达量,经历峰值后急速回落,在后熟中后期表达水平较低。1-MCP处理下,在整个后熟阶段,XanDH的表达量均显著高于对照组,在DAH17达到最大值,随后逐渐降落。与对照组相比,PP2C基因表达量持续上升,ABF基因持续下调;PYR/PYL在DAH17表达量最高而后下调,但仍显著高于对照组。表明乙烯利、1-MCP、ABA处理对海沃德猕猴桃内源ABA合成、信号传导有较大影响,本试验结果为进一步探究外源乙烯利、1-MCP和ABA对猕猴桃果实采后衰老的调控作用及机理提供了一定的理论依据。     

石灰和绿肥对不同种植制度植烟酸性土壤改良效果

为寻求酸性植烟土壤可持续改良方法,采用大田试验研究了石灰、石灰+绿肥在烤烟连作、烤烟与玉米轮作方式上对酸性植烟土壤物理特性、主要养分和酸度特征指标的影响,并分析了土壤pH与土壤理化指标的相关性。结果表明:在烤烟连作方式下,施用石灰并结合种植绿肥还田改良酸性土壤比单施石灰效果好,能使土壤容重、水解性酸、交换性酸、交换性氢和交换性铝分别降低11.97%,25.00%,18.46%,21.74%和16.67%,土壤孔隙度、有机质、碱解氮、有效磷、速效钾含量、pH、阳离子交换量、盐基饱和度和土壤缓冲容量分别提高42.26%,57.02%,11.86%,16.39%,50.65%,5.97%,8.05%,13.17%和81.90%。施用石灰并结合种植绿肥对烤烟与玉米轮作方式的酸性土壤修复效果较烤烟连作更好,土壤容重、水解性酸、交换性酸、交换性氢和交换性铝可分别降低4.00%,20.51%,27.92%,10.00%和37.14%,土壤孔隙度、有机质、碱解氮、有效磷、速效钾含量、pH、阳离子交换量、盐基饱和度和土壤缓冲容量可分别提高9.17%,13.97%,7.22%,12.06%,5.08%,5.15%,35.27%,15.44%和28.05%。石灰+绿肥协同改良酸性土壤的效果比单施石灰好,烤烟与玉米轮作较烤烟连作更有利于酸化土壤的修复。研究结果为采用石灰和种植绿肥还田改良酸性土壤提供了理论依据和实践指导。     

不同组分的腐植酸复合肥在辣椒上的施用效应及其生理机制研究

采用盆栽试验方法,研究了不同组分的腐植酸复合肥对辣椒生长及其生理特性的影响,以筛选出适于辣椒生长的最佳肥料方案。试验结果表明,不同组分腐植酸复合肥处理与等养分无机复合肥及对照相比,产量均有显著提高,提高幅度分别为8.1％～23.5％和165.0％～195.1％。其中以HAzn增产效果最为显著。对辣椒生理活性的影响,也是以HAZn总体表现效果最佳,它可提高辣椒体内NR、SOD、POD的活性,促进叶绿素的合成代谢。此外,微量元素锌、铁之间存在着一定的拮抗作用,在一个施肥方案中,二者不宜同时施用。     

不同氮高效玉米品种对氮素的吸收转运和代谢研究

为研究不同氮高效型品种的氮素代谢调控机制,本试验以高氮高效型玉米品种先玉335和低氮高效型玉米品种京农科728为试材,设置5个施氮水平120、180、240、300、360 kg·hm^-2,以本地大田生产施氮量360 kg·hm^-2为对照(NCK),探讨不同基因型玉米植株氮素转运、氮代谢关键酶活性和关键酶基因表达对减施氮肥的响应特征。结果表明,当施氮量为240～300 kg·hm^-2时,先玉335各生育时期氮含量较高,平均产量达到较高水平;当施氮量为180～240 kg·hm^-2时,京农科728各生育时期氮含量较高,平均产量达到较高水平。在低氮条件下,相较于先玉335,京农科728的硝酸还原酶(NR)、亚硝酸盐还原酶(NiR)、谷氨酰胺合成酶(GS)、谷氨酸合成酶(GOGAT)、天冬酰胺合成酶(AS)均可保持较高的活性。相较于拔节期,京农科782在大喇叭口期的NR基因相对表达量显著上调;大喇叭口至灌浆期,两品种的GOGAT1和GOGAT2基因均显著上调;抽雄吐丝和灌浆期,京农科728中的GS1-3基...     

温度对EGCG和柠檬酸活化土壤硅铝铁锰的影响

通过浸提试验研究了温度对浓度均为5 mmol/L的表没食子儿茶素没食子酸脂(EGCG)和柠檬酸活化漂洗水稻土和黄壤矿质元素的影响。结果表明:随温度升高,EGCG和柠檬酸对2种土壤Si、Al、Fe和Mn的活化量均不同程度增加,表明EGCG和柠檬酸活化土壤矿质元素的能力在高温季节将得以增强。相同温度下,从元素间比较来看,EGCG和柠檬酸对2种土壤元素的活化量大小均为AlSiFe(Mn),表明EGCG和柠檬酸作用下土壤Al较Si、Fe和Mn更易活化;柠檬酸对2种土壤Fe、Mn的活化量均为FeMn,而EGCG对漂洗水稻土为FeMn,对黄壤则为MnFe;从土壤间比较来看,EGCG和柠檬酸对2种土壤Si的活化量均为漂洗水稻土黄壤,对Al、Fe和Mn的活化量则为黄壤漂洗水稻土;从酚与酸的比较来看,柠檬酸对2种土壤Si、Al、Fe的活化量均显著高于EGCG,表明柠檬酸比EGCG对土壤Si、Al和Fe有更强的活化能力。     

丁香酸对不同品种烟草苗期根系生长的影响

为探究最新发现的植物源生物硝化抑制剂丁香酸对烟草品种K326和云烟85苗期根系生长的影响,通过基质培养试验,设置0、10、25、50、100、200 μmol/L 6个丁香酸浓度,研究了不同浓度丁香酸在不同时间(3 d和5 d)对K326和云烟85主根伸长量和一级侧根发育的影响。结果表明:与对照(0 μmol/L)相比,25～100 μmol/L丁香酸能促进K326主根伸长,在3 d时促进率为13.33%～30.67%,在5 d时促进率降为8.54%～22.55%,最适浓度为50 μmol/L;10～50 μmol/L丁香酸促进云烟85主根伸长,在3 d时促进率为7.81%～18.75%,在5 d时促进率维持在4.10%～10.66%,最佳促进浓度25 μmol/L;丁香酸对两个烟草品种主根伸长的促进效果均为3 d优于5 d。在侧根发育方面,低浓度丁香酸能显著促进K326和云烟85一级侧根数,两个品种促进侧根发育的最适浓度均为25 μmol/L。相关性分析表明,丁香酸处理下两个烟草品种苗期的主根伸长变化率与侧根数变化率呈显著正相关。可见,适宜浓度的丁香酸对两个典型烟草品种苗期主根增长和...     

不同施肥条件下生物腐植酸对磷的转化效果分析

在实验室利用4个土槽分别施入复合化肥（CF）、普通有机肥（OF）、生物有机肥（BF）和不施肥（CK）来改变土壤中磷的基础含量,另取4个土槽在相应处理中配施相同的生物腐植酸,以15°角放入自制的降雨淋溶装置下进行试验,观测径流液中的全磷含量,以分析研究生物腐植酸对土壤和不同施肥条件下磷的转化效果.结果显示,施用复混肥、普通有机肥和生物有机肥降雨3h后,径流液中磷（P）流出量分别为不施肥处理（CK）的2.90、1.32和9.73倍,而相同处理配施生物腐植酸后,复混肥、普通有机肥、生物有机肥处理的径流液中P含量有增有减,分别为CK的7.09、2.32和5.00倍.表明在施用复混肥、普通有机肥的土样中加入生物腐植酸能够有效释放肥料中的磷素,使之转化为更利于植物吸收的可溶性磷,其转化率分别为0.76％和0.37％;而在施用生物有机肥的土样加入生物腐植酸反而抑制磷的转化,其转化率为-0.85％.不仅如此,加施生物腐植酸还能改变磷的转化进程,使CK和OF处理的磷含量峰值由出现在第3小时变为出现在第2小时,使CF处理的磷含量峰值由出现在第2小时变为出现在第1小时,加速了磷释放.由此可得,生物腐植酸能有效释放肥料中的磷素、使之转化为更利于植物吸收的可溶性磷并加速其转化进程.研究结果可作为推广生物腐植酸的依据和有关作物磷吸收研究的基础.     

Fecal Sterol and Bile Acid Biomarkers: Runoff Concentrations in Animal Waste-Amended Pastures

Nonpoint source pollution is the leading remaining cause of water quality problems. The extent of NPS pollution is often more difficult or expensive to monitor at the point(s) of origin, as compared to monitoring of point sources. This study evaluated the hypothesis that animal manure (chicken, cow, horse, and pig) applied to pasture contribute fecal sterols and bile acids to runoff. The study also assessed the potential benefit of fecal sterols and bile acids as biomarkers in distinguishing fecal pollution and its sources. Fecal sterol and bile acid concentrations were determined in flow-weighted composite runoff samples collected from 2.4?×?6.1 m plots (n?=?3) amended with manure. Runoff was generated from simulated rainfall (152 mm.h^?1). Runoff samples from manure-amended plots showed high concentrations of fecal sterol (ranged from 13?±?1 to 1,287?±?183) and bile acid (ranged from 24?±?1 to 2,251?±?248) biomarkers. The profiles of fecal sterols and bile acids in runoff samples were similar to those of fresh manure for all selected animals. For runoff and fresh manure, chenodeoxycholic acid, deoxycholic acid, epicoprostanol, and hyodeoxycholic acid were consistent biomarkers for chicken, cow, horse, and pig, respectively, suggesting that sterols and bile acids can be used to identify sources and occurrence of fecal matter in water and sediments.