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Gene delivery into isolated

Nan Zheng, Ziyuan Song, Yang Liu, Lichen Yin, Jianjun Cheng

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 521-528 doi: 10.1007/s11705-017-1612-8

摘要： The application of gene delivery materials has been mainly focused on mammalian cells while rarely extended to plant engineering. Cationic polymers and lipids have been widely utilized to efficiently deliver DNA and siRNA into mammalian cells. However, their application in plant cells is limited due to the different membrane structures and the presence of plant cell walls. In this study, we developed the cationic, -helical polypeptide that can effectively deliver DNA into both isolated protoplasts and intact leaves. The PPABLG was able to condense DNA to form nanocomplexes, and they exhibited significantly improved transfection efficiencies compared with commercial transfection reagent Lipofectamine 2000 and classical cell penetrating peptides such as poly(L-lysine), HIV-TAT, arginine9, and poly(L-arginine). This study therefore widens the utilities of helical polypeptide as a unique category of gene delivery materials, and may find their promising applications toward plant gene delivery.

关键词： α-helical polypeptide plant gene delivery protoplast intact leaves transfection

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Optimization of methyl orange removal from aqueous solution by response surface methodology using spent tea leaves

Liangzhi LI,Xiaolin LI,Ci YAN,Weiqiang GUO,Tianyi YANG,Jiaolong FU,Jiaoyan TANG,Cuiying HU

《环境科学与工程前沿（英文）》 2014年第8卷第4期页码 496-502 doi: 10.1007/s11783-013-0578-0

摘要： The effective disposal of redundant tea waste is crucial to environmental protection and comprehensive utilization of trash resources. In this work, the removal of methyl orange (MO) from aqueous solution using spent tea leaves as the sorbent was investigated in a batch experiment. First, the effects of various parameters such as temperature, adsorption time, dose of spent tea leaves, and initial concentration of MO were investigated. Then, the response surface methodology (RSM), based on Box–Behnken design, was employed to obtain the optimum adsorption conditions. The optimal conditions could be obtained at an initial concentration of MO of 9.75 mg·L , temperature of 35.3°C, contact time of 63.8 min, and an adsorbent dosage 3.90 g·L . Under the optimized conditions, the maximal removal of MO was 58.2%. The results indicate that spent tea leaves could be used as an effective and economical adsorbent in the removal of MO from aqueous solution.

关键词： spent tea leaves adsorption response surface methodology methyl orange (MO)

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A comparison of the biological activities of ethyl acetate fractions from the stems and leaves of

Zhaolei WANG, Kai JIANG, Qinchao DING, Shujun LIU, Xiaobing DOU, Bin DING

《农业科学与工程前沿（英文）》 2020年第7卷第4期页码 505-512 doi: 10.15302/J-FASE-2019271

摘要：

Pursh (PCP) is a popular traditional medicinal plant in China, widely used for the treatment of a variety of liver diseases. Although it has been long recognized that the main active elements of PCP are contained in ethyl acetate fraction (EAF), little is known so far in terms of the relative effectiveness of EAF derived from the stems versus leaves of this plant. In the current study, we prepared EAF by reflux extraction and sequential extraction from the stems (SEAF) and leaves (LEAF) of PCP and tested their hepatoprotective efficacies. The extract rates and flavonoid contents of LEAF were higher than those of SEAF. EAFs (>50 μg·mL ) prevented lipid accumulation in cells and protected against lipotoxicity injury when the concentration exceeded 25 μg·mL . More than 95% free radicals released by 2,2-diphenyl-1-picrylhydrazyl (DPPH) were eliminated by 25 μg·mL SEAF and 50 μg·mL LEAF, respectively. Further, EAFs (25 μg·mL ) also showed protective antioxidant effects, with the activity of LEAF being significantly higher than that of SEAF. EAFs (10 mg·mL ) also showed similar unspecific bacteriostatic activity. In comparison with SEAF, LEAF contained more flavonoids and had a higher anti-oxidation capability and for these reasons we suggest it should be better for clinical use.

关键词： antibacterial anti-oxidation lipid accumulation lipotoxicity Penthorum chinense Pursh

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liquid chromatography for the separation and purification of Quercetin-3- O -sambubioside from the leaves

Shengguo DENG, Zeyuan DENG, Yawei FAN, Jing LI, Rong LIU, Dongmei XIONG,

《化学科学与工程前沿（英文）》 2009年第3卷第4期页码 375-382 doi: 10.1007/s11705-009-0247-9

摘要： Quercetin-3--sambubioside Quercetin-3--β-D-xylopyranosyl (1→2)-β-D-glucopyranoside was separated and purified by semi-preparative high-speed counter-current chromatography (HSCCC) with a two-phase-solvent system composed of ethyl acetate-n-butanol–water (4∶1∶5, v/v) from the leaves of (Lotus). A total of 5.0mg of the targeted compound with a purity of 98.6% as determined by high performance liquid chromatography (HPLC) was obtained from 100m g of the crude extract cleaned up by AB-8 macroporous resin in a one-step separation. Quercetin-3--sambubioside was a novel flavonoid glycoside from the leaves of , and its chemical structure was identified by means of ESI-MS, 1D NMR and 2D NMR.

关键词： two-phase-solvent flavonoid glycoside high-speed counter-current macroporous counter-current chromatography

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高等植物叶片色域的理论研究

程晓舫,董金一,范学良,丁金磊

《中国工程科学》 2006年第8卷第12期页码 66-69

摘要：

利用叶绿素和类胡萝卜素的经典吸收光谱以及植物叶片中不含色素的其他物质成分的光谱，分别求得其在CIE1931色品图中的理论坐标，并根据色度学中的加法混色原理确定出高等植物叶色的理论域范围。实验数据与理论相吻合。

关键词：高等植物色素吸收光谱色度坐标色域

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低水多变环境下玉米叶片的光合与反射光谱特征

孙莉,苏根强,刘艳梅,赵闫闫,史刚荣

《中国工程科学》 2012年第14卷第3期页码 70-75

摘要：

采用盆栽试验，以玉米品种苏玉19为试材，在每次复水第7天同时测定不同处理植株的生物量、根冠比、叶绿素荧光、气体交换以及光谱特征等指标。结果表明，持续干旱处理抑制植株生长，增加根冠比，并通过气孔限制和非气孔限制因素抑制光合作用。持续干旱处理幼苗的mSR705、chlNDI和REP均显著小于对照，但对SIPI的影响不显著。多变低水环境下玉米幼苗生长明显受到抑制，但根冠比、叶绿素荧光、气体交换以及光谱特征等指标与正常供水没有差异。可见，生物量分配、光合作用和光谱特征的维持可能是玉米适应多变低水环境的重要生理机制。

关键词：玉米多变低水叶绿素荧光气体交换反射光谱

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基于集成液体交换的微流控芯片的完整单细胞动态变形测量 Article

Xu Du, Di Chang, Shingo Kaneko, Hisataka Maruyama, Hirotaka Sugiura, Masaru Tsujii, Nobuyuki Uozumi, Fumihito Arai

《工程（英文）》 2023年第24卷第5期页码 94-101 doi: 10.1016/j.eng.2022.08.020

摘要：

本文报道了采用一种集成了力感应和液体交换功能的微流控芯片来测量单细胞力学性能的方法。使用光学镊子操纵和定位在推力探针和力传感器探针之间的单个细胞。这两个芯片上的探针被设计用来捕获和使细胞变形。通过移动由外力驱动的推力探针，而使单个细胞变形。层流在探针之间形成液-液界面以改变细胞外环境。通过控制注入压力来改变界面的位置。通过调整两个正压力和一个负压力来平衡流动的扩散和扰动。在微流控芯片中测定了不同渗透浓度环境下的单个集胞藻（Synechocystis）菌株PCC 6803 的力学性能。在0.3~0.7 s 内实现液体交换过程，同时也显示了单个细胞的动态变形。可以在30 s 内收集不同渗透浓度下两个杨氏模量值的测量结果以及单个细胞在渗透压冲击下的动态响应。研究了野生型（WT）和突变型集胞藻细胞的动态变形，揭示了机械敏感（MS）通道的功能机制。该系统提供了一种监测单个完整细胞响应快速外部渗透变化的实时力学动力学的新方法；因此，该系统为准确描述细胞中MS通道的生理功能提供了新的机会。

关键词：微流控芯片力学性能动态变形单细胞液体交换