Effect of Nd^3＋ on Photosynthesis of Spinach

The effect of Nd^3 on the photosynthesis and the growth of spinach was studied. The results show that Nd^3 improves the growth of spinach and increases chlorophyll content and photosynthetic rate. UV-Vis spectrum indicates that the Soret band of chl-a in spinach with NdCl3 treatment is blue shifted by 2 nm, and the Q band is red shifted by 1 nm, and the ratio of Soret band intensity and Q band intensity increases. FT-IR spectra show that the peak of porphyrin ring in chl-a of spinach with NdCl3 treatment is widened, suggesting that the formation of Nd^3 -chl-a. Treated by NdCl3, the fluorescence emission peak of PSⅡ in spinach leaves is blue shifted by 12 nm and the intensity declines obviously, indicating that Nd^3 is bound to the PSⅡ protein-pigment complex and the electron transfer rate increases.     

菠菜表面农残的SERS无损检测方法研究

本文针对菠菜农药残留量超标问题,建立了一种能够快速、无损地对菠菜表面农药残留量进行检测的方法。利用表面增强拉曼光谱技术（SERS,Surface Enhanced Raman Scattering）采集含农药（溴氰菊酯）和不含的两组菠菜样本的SERS光谱,结合一阶导加Norris求导法、Savitzky-Golay卷积求导法进行光谱预处理,使用判别分析法和距离匹配法建立定性分析模型,成功区分两组菠菜样本,模型预测准确率最高可达到100%;使用偏最小二乘法建立了菠菜表面溴氰菊酯残留量的多个定量分析模型,研究发现差谱模型效果最好,其校正集相关系数（Rc）和预测集相关系数（Rp）分别为0.9908,0.9552,校正均方根误差（RMSEC）和预测均方根误差（RMSEP）分别为0.0802,0.23。结果表明,运用SERS方法能够很好地实现菠菜表面溴氰菊酯残留量的无损定性和定量检测分析,且无需任何前处理,对其它农产品中农药残留量的快速、无损检测具有借鉴意义。      

密闭气体环境对夏菠菜硝酸盐、亚硝酸盐及贮藏品质的影响

以菠菜为实验材料,研究低温贮藏条件下(4℃)密闭气体环境对菠菜贮藏品质,尤其对硝酸盐、亚硝酸盐及硝酸还原酶等酶活性的影响。结果表明:与对照(非密闭环境)相比,低温密闭气体环境可显著减缓菠菜可溶性固形物、VC、叶绿素等贮藏品质的下降,维持菠菜较高的硝酸还原酶(NR)活性和抗逆酶活性(SOD、POD、CAT),抑制丙二醛的产生,贮藏8d硝酸盐和亚硝酸盐分别为1318.44、0.42mg/kg,较对照分别降低了31.96%、26.19%,实验表明低温密闭气体环境有效降低了硝酸盐和亚硝酸盐的累积,提升了菠菜的安全贮运品质。      

菠菜叶片线粒体DNA的提取及RAPD分析

以菠菜叶片为实验材料,采用差速离心法、DNaseI处理得到无核污染的线粒体、以SDS法去除蛋白,消化RNA得到单纯的菠菜叶片mtDNA,通过对mtDNA纯度的测定,从而建立了菠菜叶mtDNA快速、高效的提取技术体系;同时选取30个引物对三种菠菜mtDNA进行RAPD扩增,对提取的mtDNA体系进行了RAPD分析,结果表明,由引物S7、S16、S21、S24扩增出的条带清晰、多态性较好,片段大小在200~2000 bp之间,表明菠菜各品种的mtDNA各碱基序列上的多态性,是各品种之间进化凸现的原因之一。本研究建立的试验方法耗时短、对离心机的要求不高,并且提取的mtDNA产率高、结构也比较完整。     

Effect of processing methods on spinach: Proximate composition in fatty acids and soluble protein

The proximate composition and fatty acid content of spinach were determined in two processing stages. Crude protein and ash content were 2.89% and 1.96%, respectively. The total lipid content was 0-61%. The predominant fatty acids were palmitic (16:0), hexadecadienoic (16:2), hexadecenoic (16:1), stearic and hexadecatrienoic (18:0 and 16:3), oleic (18:1), linoleic (18:2) and linolenic (18:3). Little loss was observed as a result of processing. Soluble protein content showed losses of up to 87% during processing.     

鲜切菠菜在不同冷藏温度下品质变化的动力模型

通过正交设计确定了菠菜鲜切处理的最佳方案为用75 mg/L二氧化氯水溶液、0.5%氯化钠溶液分别浸泡10 min后,PVDC保鲜膜包装。然后将处理后的菠菜分别储藏于0℃、4℃、7℃、10℃,并测定了鲜切菠菜的失重率、叶绿素含量及菌落总数,跟踪样品品质随时间、温度的变化关系。结果表明,随着贮藏温度的升高和贮藏时间的延长,菠菜叶绿素含量减少;失重率则随着储藏温度的升高和贮藏时间的延长而增大;菌落总数也随着储藏温度的升高和贮藏时间的延长而增大。这表明鲜切菠菜0℃贮藏效果最好。基于实验数据,建立了失重率、叶绿素和菌落总数的动力学模型,获得了模型中的活化能参数,为流通过程中的货架期预测奠定了理论基础。     

降解菌对菠菜和土壤中氯氰菊酯残留动态的影响

通过盆栽实验,测定降解菌对菠菜体内和土壤中氯氰菊酯残留动态的影响.结果表明:在菠菜和土壤中,氯氰菊酯的残留呈现先上升后下降的过程,在喷药后3～6 h菠菜和土壤中氯氰菊酯含量达到最大值,3 h后开始逐渐减少,到24 h以后,菠菜中氯氰菊酯的含量低于1 mg/kg,达到叶菜类蔬菜氯氰葡酯农药残留的最大残留量标准;其中,具有内生性的菌株Y3对菠菜中的氯氰菊酯降解作用非常明显,而不具有内生性的菌株T1对菠菜中的氯氰菊酯降解作用就很少.     

菠菜汁低温火腿肠加工工艺研究

以猪肉为主料，菠菜汁为配料，以玉米淀粉、大豆分离蛋白等为辅料，通过单因素试验和正交试验，针对菠菜汁低温火腿肠的配方进行了研究，结果表明：菠菜汁添加量为3％、肥瘦肉比例为7：3，淀粉添加量为10％、香辛料添加量1．5％，产品质量最好。     

Nitrogen removal from eutrophic water by floating-bed-grown water spinach (Ipomoea aquatica Forsk.) with ion implantation

The aim of this study was to investigate the use of water spinach (Ipomoea aquatica Forsk.) with N(+) ion-beam implantation for removal of nutrient species from eutrophic water. The mutated water spinach was grown on floating beds, and growth chambers were used to examine the growth of three cultivars of water spinach with ion implantation for 14 days in simulated eutrophic water at both high and low nitrogen levels. The specific weight growth rates of three cultivars of water spinach with ion implantation were significantly higher than the control, and their NO(3)-N and NH(4)-N removal efficiencies were also greater than those of the control. Furthermore, compared with the control, the nitrogen contents in the plant biomass with ion implantation were higher as well.     

不同镉水平对菠菜生长及营养元素含量的影响

不同镉水平对两种菠菜澳洲大叶、新世纪全能的生长及营养元素含量影响研究结果表明:培养液中添加镉后能够抑制两种菠菜的生长,可以显著降低菠菜地上部的干重。两种菠菜地上部分及根中的镉含量随培养液中镉浓度增加而显著增加。镉主要累积在菠菜的根中。镉影响菠菜对营养元素的吸收及分配,澳洲大叶地上部的Ca、Mg、Fe和Mn的含量显著增加,新世纪全能地上部Fe含量显著增加。这种影响随着不同元素、不同植株部位及镉离子在介质中浓度的不同而有所差异,基因型间存在一定的差异。