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21.
《结构化学》2012,29(5)
为探究施肥对燕麦鲜草、秸秆和种子产量的影响,找出限制燕麦鲜草、秸秆和种子产量提高的养分因子,筛选出实现经济效益最大的施肥配方,本研究以青引1号燕麦(Avana sativa cv.Qingyin No.1)为对象,于2010年在青海省湟中县分析不同的氮、磷和钾配方施肥对燕麦产量及其构成因素的影响。结果表明,氮素为限制燕麦鲜草产量提高的主要养分因子,施氮能显著提高燕麦株高和鲜草产量,N337.5P105K60处理鲜草产量最大,为66 194kg·hm^-2,比对照增产44.9%。磷素为限制燕麦种子产量提高的主要养分因子,施磷能增加燕麦有效分蘖数、小穗数,N225P157.5K60处理下燕麦籽粒产量最大,为6 678kg·hm^-2。经过经济效益分析,N225P105K60施肥处理获得的综合收益最大,饲草田达到18 435.3元·hm^-2,种子田达到22 877.5元·hm^-2,分别比对照增收4 500.9和4 597.5元·hm^-2。  相似文献   
22.
为探讨燕麦(Avena sativa L.)对超重/肥胖伴高血压患者血压及相关指标的影响,将中青年原发性高血压Ⅰ -Ⅱ级伴有超重/肥胖患者70例受试者随机均分为A、B两组,进食或不进食麦片,5周后,两组的干预措施对调,进行自身对照.结果显示两组患者在实验期的舒张压(SBP)、收缩压(DBP)、腰围、体重指数(BMI)、WHR、TG和TC的值均有明显降低;其中两组实验期的SBP和BMI较各自自身对照期有显著降低(P<0.05).故燕麦对超重/肥胖伴高血压患者血压及相关指标有明显的降低作用,可供临床选择饮食干预辅助治疗超重/肥胖伴高血压时推荐使用.  相似文献   
23.
Two-dimensional correlation spectroscopy (2DCOS) and near-infrared spectroscopy (NIRS) were used to determine the polyphenol content in oat grain. A partial least squares (PLS) algorithm was used to perform the calibration. A total of 116 representative oat samples from four locations in China were prepared and the corresponding near-infrared spectra were measured. Two-dimensional correlation spectroscopy was employed to select wavelength bands for the PLS regression model for the polyphenol determination. The number of PLS components and intervals was optimized according to the coefficients of determination (R2) and root mean square error of cross validation (RMSECV) in the calibration set. The performance of the final model was evaluated using the correlation coefficient (R) and the root mean square error of validation (RMSEV) in the prediction set. The results showed the band corresponding to the optimal calibration model was between 1350 and 1848?nm and the optimal spectral preprocessing combination was second derivative with second smoothing. The optimal regression model was obtained with an R2 of 0.8954 and an RMSECV of 0.06651 in the calibration set and R of 0.9614 and RMSEV of 0.04573 in the prediction set. These measurements reveal the calibration model had qualified predictive accuracy. The results demonstrated that the 2DCOS with PLS was a simple and rapid method for the quantitative determination of polyphenols in oats.  相似文献   
24.
燕麦作为一种营养独特的作物,用于酿造黄酒是黄酒酿造研究的一项新的尝试。为进一步探究燕麦黄酒中的高级醇指标、微生物群落结构及其相关性,研究燕麦黄酒特性,本研究应用顶空固相微萃取、气相色谱-质谱联用技术对燕麦黄酒发酵过程中的高级醇变化进行了定量分析,并通过高通量测序检测了燕麦黄酒发酵过程中的微生物群落结构变化。利用统计学原理对高级醇变化与微生物代谢之间的相关性进行预测。燕麦黄酒中共检测到β-苯乙醇、异戊醇等18种高级醇。门水平上,相对丰度最高的细菌和真菌分别是厚壁菌门和子囊菌门;属水平上,相对丰度最高的细菌和真菌分别是乳球菌属和酵母属。高级醇与微生物间共建立869项关联,有297属微生物可能参与高级醇的代谢。本研究表明,以燕麦为原料酿造黄酒不仅可以增加黄酒的品类及原料来源,还可能改善黄酒营养价值;另外,高级醇与微生物之间的关联分析可以预测燕麦黄酒品质特性的生物学机制。  相似文献   
25.
The oat β-glucan (OG) was added into set-type yogurt as a functional ingredient, in order to evaluate effects on the rheological characteristics and microstructure of set-type yogurt. When the OG concentration increased from 0 to 0.3%, the WHC gradually increased. At 0.3% OG, the set-type yogurt had the highest WHC of 94.67%. Additionally, the WHC continuously decreased, reaching the lowest WHC (about 80%) at 0.5% OG. When 0.3% OG was added, the highest score of sensory evaluation was about 85. The rheological result showed that the fermentation process went through the changes as follows: solid → liquid → solid → liquid. The addition of 0.3% OG decreased the fermentation time of set-type yogurt by about 16 min, making yogurt more inclined to be liquid. The acidity of set-type yogurt with OG was slightly higher. The result of microstructure showed that the addition of OG destroyed the three-dimensional network structure of yogurt, and some spherical aggregate particles could be clearly observed at 0.3% OG. Overall, this study provided a theoretical basis for the application of OG in set-type yogurt.  相似文献   
26.
Oat (Avena sativa) is well known for its various health benefits. The protective effect of oat extract against oxidative stress-induced apoptosis in human keratinocytes HaCaT was determined. First, extracts of two varieties of oat, Daeyang and Choyang, were analyzed for fat-soluble antioxidants such as α-tocotrienol, γ-oryzanols, lutein and zeaxanthin using an UPLC system and for antioxidant activity using a DPPH assay. Specifically, an 80% ethanol extract of Daeyang oat (Avena sativa cv. Daeyang), which had high amounts of antioxidants and potent radical scavenging activity, was further evaluated for protective effect against oxidative stress-induced cell death, intracellular reactive oxygen species levels, the phosphorylation of DNA damage mediating genes such as H2AX, checkpoint kinase 1 and 2, and p53 and the activation of apoptotic genes such as cleaved caspase-3 and 7 and poly (ADP-ribose) polymerase in HaCaT cells. The Daeyang and Choyang oat 80% ethanol extracts had 26.9 and 24.1 mg/100 g γ-oryzanols, 7.69 and 8.38 mg/100 g α-tocotrienol, 1.25 and 0.34 mg/100 g of lutein and 1.20 and 0.17 mg/100 g of zeaxanthin, respectively. The oat 80% ethanol extract treatment (Avena sativa cv. Daeyang) had a protective effect on oxidative stress-induced cell death in HaCaT cells. In addition, the oat 80% ethanol extracts led to a significant decrease in the intracellular ROS level at a concentration of 50–200 μg/mL, the attenuation of DNA damage mediating genes and the inhibition of apoptotic caspase activities in a dose dependent manner (50–200 μg/mL). Thus, the current study indicates that an oat (Avena sativa cv. Daeyang) extract rich in antioxidants, such as polyphenols, avenanthramides, γ-oryzanols, tocotrienols and carotenoids, has a protective role against oxidative stress-induced keratinocyte injuries and that oat may a useful source for oxidative stress-associated skin damage.  相似文献   
27.
对四株不同属的真菌进行单独培养及两两混合培养,观察其长势,分别测定其粗酶液的木聚糖酶活性、纤维素酶活性、燕麦秸秆降解能力,比较不同混合菌组合发酵后,菌之间、酶之间存在的协同作用和拮抗作用.试验结果表明:单菌发酵长势优于混菌发酵;单菌FQ7-31、P647生长最佳,组合FQ7-31与P647生长中拮抗作用最强.单菌发酵产木聚糖酶活性明显高于混菌发酵,T537单菌发酵后木聚糖酶活性最高达49.3U/g,组合P647与T537拮抗作用最强,木聚糖酶活性与长势之间呈负相关.单菌发酵后纤维素酶活性明显低于混菌,因此混菌发酵后纤维素酶活性存在着协同作用,协同作用最强的组合是P647与T537.粗酶液对秸秆的降解作用中,FQ7-31与其他三属真菌之间存在着明显的协同作用.发酵120小时后,A3.3567培养基中还原糖产量最高.  相似文献   
28.
应用固相微萃取技术(SPME)和气相色谱-质谱联用技术(GC-MS)分别对普通小麦面包、普通燕麦面包(含质量分数为20%燕麦粉)、燕麦酸面团面包(用10%燕麦酸面团取代燕麦面包中10%的燕麦粉)以及燕麦酸面团冷冻干燥(冻干)粉面包(用10%燕麦酸面团冻干粉取代燕麦面包中10%的燕麦粉)中的挥发性风味物质进行研究,考察植物乳杆菌燕麦酸面团发酵剂及其冻干工艺对面包风味的影响.结果表明:所有样品中共检测出57种风味物质,主要包括醇类、酸类、醛类、酯类、酮类、脂肪烃类,以及一些芳香族和杂环类化合物.醇类物质的含量最高,其次是芳杂环类、醛类和酸类物质.与普通小麦面包相比,添加燕麦粉面包的风味物质种类更多;甲苯、庚醇、1,3-丙二醇二乙酸酯、辛酸共同存在于3种燕麦面包中,而在普通小麦面包中未检测出.冻干过程中会丧失一些风味物质或风味前体物质,与燕麦酸面团冻干粉面包相比,燕麦酸面团面包中含有一些独有风味物质,分别是双乙酰、2-戊酮、庚酸乙酯、2-乙酰基噻唑、香叶基丙酮.  相似文献   
29.
张伦  张庆勤 《贵州科学》1991,9(2):109-113,115,116
本文对黑龙江野生燕麦、栽培燕麦的染色体组型作了观察分析(图1,图3),绘制了它们的核型模式图(图2,图4)。并进行了二者核型间的比较研究,结果如下: 黑龙江野生燕麦与栽培燕麦的六倍体染色体数日皆为2n=6x=42。除No.1、No.3、No.6染色体黑龙江野生燕麦臂为“m”型而栽培燕麦皆为“sm”型之外、其余的18对染色体类型皆一一对应一致。黑龙江野生燕麦的核型公式为2n=6x=42=28m(2STA)+14sm。栽培燕麦的是2n=6x=42=22m+20sm。在黑龙江野生燕麦的No.3染色体一臂上可见一对明显的随体,而在栽培燕麦的核型分析中未发现有随体染色体。另外,黑龙江野生燕麦的核型类别为较原始的“2A”型,而栽培燕麦的核型类别是比“2A”型较进化的“2B”型。此外,在研究过程中,对如何才能得到分散度较高的染色体图相,也做了方法上的探讨。  相似文献   
30.
斯卑尔脱小麦Triticum spelta L.f.duhamelianum 2n=6x=42与通北野生燕麦Avena fatua L.2n=6x=42直接杂交成功,结实率36%。F_1代表现不一致,出现4种类型,主要类型结实基本正常,其他3个类型,有2个类型结实率约10%,有1个类型完全不结实;均表现为斯卑尔脱型,成熟期同通北野生燕麦,比斯卑尔脱小麦早熟10天。F_1植株花粉母细胞镜检表明,大多数染色体配对正常,单价体2—4个。F_2植株花粉母细胞镜检表明,大多数植株染色体配对正常,2n=42,少数植株染色体出现1—5个单价体。F_2分离很大,出现约10%容易脱粒不断穗节的普通小麦型,其中一部分综合抗病和综合丰产性均好,并出现超亲矮杆的普通小麦型植株,最矮的株高仅57厘米。株高80—90厘米的类型较多,籽粒饱满,千粒重最高的达到60克。可以直接育成多抗优质高产的新型普通小麦。普通小麦型植株大多数表现抗白粉病、条锈病和叶锈病。  相似文献   
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