The effect of cerium (III) on the chlorophyll formation in spinach

The effect of Ce³⁺ on the chlorophyll (chl) of spinach was studied in pot culture experiments. The results showed that Ce³⁺ could obviously stimulate the growth of spinach and increase its chlorophyll contents and photosynthetic rate. It could also improve the PSII formation and enhance its electron transport rate of PSII as well. By inductively coupled plasma-mass spectroscopy and atom absorption spectroscopy methods, it was revealed that the rare-earth-element (REE) distribution pattern in the Ce³⁺-treated spinach was leaf>root>shoot in Ce³⁺ contents. The spinach leaves easily absorbed REEs. The Ce³⁺ contents of chloroplast and chlorophyll of the Ce³⁺-treated spinach were higher than that of any other rare earth and were much higher than that of the control; it was also suggested that Ce³⁺ could enter the chloroplast and bind easily to chlorophyll and might replace magnesium to form Ce-chlorophyll. By ultraviolet-visible, Fourier transform infrared, and extended X-ray absorption fine structure (EXAFS) methods, Ce³⁺-coordinated nitrogen of porphyrin rings with eight coordination numbers and average length of the Ce-N bond of 0.251 nm.     

黄孢原毛平革菌抗营养阻遏产漆酶诱变育种及其产酶特性

【目的】筛选能抗营养阻遏产漆酶的黄孢原毛平革菌,论证其产漆酶的确定性及抗营养阻遏产木质素酶的可行性,为白腐菌产酶代谢调控、木质素降解机理的研究奠定基础。【方法】利用重复紫外诱变法,以愈创木酚富氮鉴别培养基筛选目标菌株;比较不同营养条件下菌体生长与产酶动力学差异研究产酶营养调控机理;通过热处理、排除锰离子和加入过氧化氢酶等不同措施论证黄孢原平毛平革菌能否产生漆酶。【结果】3种不同方法均证实选育到的pcR5305和pcR5324菌株在限氮与富氮条件下均能产生漆酶,pcR5305和pcR5324在限氮条件下产漆酶分别达到203.5、187.6 U/L;在富氮条件下为220.6、183.9 U/L,而原菌株pc530在两种条件下都基本不产生漆酶。二菌株产漆酶调控方式不同,pcR5305漆酶产生与菌体生长同步,而pcR5324漆酶产生却受营养氮阻遏。二菌株同时具有抗营养阻遏高产木质素过氧化物酶(LiP)和锰过氧化物酶(MnP)(分别为LiP 1343.2、MnP 252.2 U/L;LiP 1169.5、MnP 172.4 U/L)的能力。【结论】筛选到的黄孢原毛平革菌变异菌株能产漆酶,同时表现了抗营养阻遏产漆酶、木质素过氧化物酶和锰过氧化物酶的能力,具有重要的生产应用与理论研究价值,为白腐菌产酶代谢调控机理研究提供了原始菌株并奠定了良好的基础。     

凝血瀑布机制的序结构分析方法

凝血系统的瀑布机制揭示了凝血因子间的酶促级联反应过程。在级联反应中,各个因子间明显地存在着序关系,而这种序关系的全体构成了系统的序结构。从系统论的观点看,系统的结构是系统性质与功能的基础,因此,通过模型化方法以及利用凝血因子序结构图建立的序结构分析方法,是分析凝血系统各因子相互作用的有用的工具。对蛋白Ｃ及ＴＦＰＩ进行序结构分析,进一步阐明了这两种抑制剂对外源途径凝血的作用特点。     

AIDA Selectively Mediates Downregulation of Fat Synthesis Enzymes by ERAD to Retard Intestinal Fat Absorption and Prevent Obesity

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黑木耳黑色素对急性肝损伤的改善作用

黑色素是一种广泛存在于动物、植物、细菌及真菌中的生物色素,具有多种生物功能及良好的生物活性。黑木耳以“黑”出名,其富含的黑色素具有广阔开发应用价值。本研究旨在评价黑木耳黑色素对急性肝损伤的改善作用。首先应用傅里叶红外光谱初步对提取的黑木耳黑色素进行鉴定,再通过DPPH自由基及羟基自由基清除实验证实提取的黑木耳黑色素体外抗氧化能力,并进一步以四氯化碳致小鼠急性肝损伤为模型,通过检测血清酶指标、肝功指标的变化及病理切片情况,来评价黑木耳黑色素体内抗氧化及保肝效果。结果表明,提取的黑木耳黑色素具有黑色素特征的官能团结构和良好的体外抗氧化能力,对DPPH自由基和羟基（OH）自由基清除的EC₅₀分别为0.0887mg/mL、2.2030mg/mL;动物体内实验中,与模型组对比,给药组（黑木耳黑色素）的小鼠血清中ALT、AST含量显著降低（P<0.01）,肝脏中MDA含量显著降低（P<0.01）和SOD活性显著升高（P<0.01）,并且肝细胞病理状态明显改善。本文报道了黑木耳黑色素在体内能有效改善四氯化碳诱导的小鼠肝损伤,为黑木耳的功能产品开发提供了新思路和研究基础。     

Trapping effect of synthetic sex pheromone of Acleris fimbriana (Lepidoptera: Tortricidae) in Chinese northern orchard

The yellow tortrix, Acleris fimbriana Merick (Lepidoptera: Tortricidae), is an economically important insect pest on fruit trees with four generations a year in North China. In order to develop a new and effective method for forecasting and controlling the pest, the sex pheromone was studied. We have identified the female sex pheromone as (E)-11,13-tetradecadienal (E11,13-14:Ald), (E)-11,13-tetradecadienyl acetate (E11,13-14:Ac) and (E)-11-tetradecenyl acetate (E11-14:Ac). Trapping effect of synthetic chemicals E11,13-14:Ald, alone and in combination with E11,13-14:Ac or/and E11-14:Ac to A. fimbriana males was tested in Beijing Xishan Orchard (2001). E11,13-14:Ald on its own was much attractive to A. fimbriana males. Neither E11,13-14:Ac nor E11-14:Ac alone caught any moths. The catches markedly increased by adding E11,13-14:Ac to E11,13-14:Ald. The optimum ratio of E11,13-14:Ald and E11,13-14:Ac was 6:4 to 5:5. This attractiveness was apparently enhanced when 5% to 10% of E11-14:Ac was added. The best field activity was in the lure baited with a 6:4:1 ratio of E11,13-14:Ald, E11,13-14:Ac and E11-14:Ac at a dosage of 1000 microg/septum. The effect of antioxidant, 2,6-di-tert-butyl-4-methylphenol [butylated hydroxyluene (BHT)], to the synthetic pheromone blends on its duration and catching efficacy was also tested. Addition of 5-10% BHT to the synthetic pheromone could prolong the life-span of pheromone chemicals for 6-8 weeks, thereby increased its catching efficacy.     

Cytotoxic,clonal fidelity,and antioxidant evaluation of in vitro propagated Vitex negundo var. cannabifolia

Plant Cell, Tissue and Organ Culture (PCTOC) - Vitex negundo L. var. cannabifolia (Sieb. et Zucc.) Hand.-Mazz. is an important medicinal plant rich in bioactive compounds. In vitro tissue culture...     

Biodegradation and detoxification of nicotine in tobacco solid waste by a Pseudomonas sp.

A Pseudomonas sp. grew with nicotine optimally 3 g l^–1 and at 30 °C and pH 7. Nicotine was fully degraded within 10 h. The resting cells degraded nicotine in tobacco solid waste completely within 6 h in 0.02 m sodium phosphate buffer (pH 7) at maximally 56 mg nicotine h^–1 g dry cell^–1.     

Synergism and Rules from Combination of Baicalin,Jasminoidin and Desoxycholic acid in Refined Qing Kai Ling for Treat Ischemic Stroke Mice Model

Refined Qing-Kai-Ling (QKL), a modified Chinese medicine, consists of three main ingredients (Baicalin, Jasminoidin and Desoxycholic acid), plays a synergistic effect on the treatment of the acute stage of ischemic stroke. However, the rules of the combination and synergism are still unknown. Based on the ischemic stroke mice model, all different kinds of combination of Baicalin, Jasminoidin, and Desoxycholic acid were investigated by the methods of neurological examination, microarray, and genomics analysis. As a result, it confirmed that the combination of three drugs offered a better therapeutical effect on ischemic stroke than monotherapy of each drug. Additionally, we used Ingenuity pathway Analysis (IPA) and principal component analysis (PCA) to extract the dominant information of expression changes in 373 ischemia-related genes. The results suggested that 5 principal components (PC1-5) could account for more than 95% energy in the gene data. Moreover, 3 clusters (PC1, PC2+PC5, and PC3+PC4) were addressed with cluster analysis. Furthermore, we matched PCs on the drug-target networks, the findings demonstrated that Baicalin related with PC1 that played the leading role in the combination; Jasminoidin related with PC2+PC5 that played a compensatory role; while Desoxycholic acid had the least performance alone which could relate with PC3+PC4 that played a compatible role. These manifestations were accorded with the principle of herbal formulae of Traditional Chinese Medicine (TCM), emperor-minister-adjuvant-courier. In conclusion, we firstly provided scientific evidence to the classic theory of TCM formulae, an initiating holistic viewpoint of combination therapy of TCM. This study also illustrated that PCA might be an applicable method to analyze the complicated data of drug combination.