好氧反硝化细菌及其在微污染水源水修复中的应用研究进展

相比于氨氮,天然水体中的硝酸盐氮通常更稳定,导致更难将其从水中去除。由于好氧反硝化可以在有氧环境下进行反硝化作用去除硝酸盐氮,该过程对含有较高溶解氧的天然水体中硝酸盐氮处理有重要作用。本文综述了好氧反硝化菌的分离纯化现状、微生物代谢机制和环境影响因子,并介绍了功能菌群在微污染饮用水源水生物修复的应用研究进展。与一般的厌氧反硝化类似,好氧反硝化菌的种属分布较广,常见的如假单胞菌属(Pseudomoas)、产碱杆菌属(Alcaligenes)、副球菌属(Paracoccus)和芽孢杆菌属(Bacillus)等所属部分微生物均有好氧反硝化能力。大部分好氧反硝化菌株在最佳生长条件下(25–37℃、溶解氧浓度为3–5mg/L、pH为7–8、碳氮比为5–10)具有高效的脱氮效率。但目前好氧反硝化作用在微污染饮用水源水的生物修复方面的应用仍有着脱氮性能不稳定、菌剂流失等不足。此外,目前较少相关中试及实际工程应用的研究,需要进一步的深入探究。     

Rapid Analysis of Four Alkaloids in <i>Uncaria rhynchophylla</i> by Core-Shell Column HPLC and Quantitative Analysis of Multi-Components by Single Marker (QAMS)

As a traditional herbal medicine, the major alkaloids in Uncaria rhynchophylla have been proven to have blood pressure-lowering and sedative effects. It is essential to develop an effective method for the determination of the major alkaloids in U. rhynchophylla. In this research, a rapid quantitative analysis involving multi-components analysis by a single marker strategy coupled with core-shell column HPLC was adopted to analyse four alkaloids (corynoxeine, isocorynoxeine, isorhynchophylline, rhynchophylline) in U. rhynchophylla. Isorhynchophylline was selected as the internal reference substance, the content of which was determined by the traditional external standard method. Relative correction factors (RCF) between isorhynchophylline and the other three alkaloids were calculated respectively. The results showed that the QAMS method had good robustness under different HPLC instruments. Nineteen batches of U. rhynchophylla were tested. No significant difference was observed between the results by QAMS and EMS (Correlation coefficient > 0.99, p > 0.05). The QAMS method could be employed as a rapid, effective technique for the quality control of U. rhynchophylla.     

A Rapid Determination of 30 Prohibited Pesticide Residues in Lycii Fructus by UPLC-MS/MS

Prohibited pesticide residues have become one of the main factors affecting the quality and safety of Lycii Fructus, However, rarely studies focus on the rapid determination of these residues. Here, a total of 30 kinds of prohibited pesticide residues were determined by ultra-performance liquid chromatography tandem triple quadrupole mass spectrometry (UPLC-MS/MS) in five different process ways. Pretreatment methods, chromatographic separation and detection conditions in mass spectrometry were all optimized accordingly. Among the five different pretreatment methods, the first and third solid phase extraction failed to provide high recoveries of sulfosulfuron compounds (both lower than 60%). Recovery of chlorphenamidine by the Quick Easy Cheap Effective Rugged and Safe multiresidue method (QuEChERS) was lower than 60%, which did not meet the requirements of trace determination. The concentrations of 30 prohibited pesticides residues treated by straightforward and solid phase extraction showed good linearity in their corresponding ranges, with correlation coefficients over 0.99. The average recoveries of straightforward ranged from 78.13% to 110.9%, while RSD ranged from 1.3% to 16.9%, albeit poor purification was observed. The recovery yield from solid phase extraction was between 67.75% and 103.08% with RSD value from 0.8% to 14.0%, which met the requirements of trace determination, this method has good precision and stability. These results could be employed to other Traditional Chinese Medicines (TCMs) in detecting prohibited pesticide residues.     

肠道菌群在脊髓损伤后胃肠道炎症反应中的研究进展

脊髓损伤(spinal cord injury, SCI)目前尚无有效的治疗手段。脊髓损伤后,患者常伴有严重的胃肠功能障碍,严重影响患者的生活质量。研究发现,脊髓损伤后肠道菌群的紊乱和脊髓损伤后的胃肠道功能障碍密切相关。因此,本文围绕脊髓损伤后肠道菌群的变化,探讨肠道菌群在迷走神经、下丘脑-垂体-肾上腺和肠道菌群代谢物3个途径中发挥的作用,及与胃肠道炎症反应相关的研究进展。     

The int genes of bacteriophages P22 and λ are regulated by different mechanisms

Bacteriophage P22 and λ are related bacteriophages with similar gene organizations. In λ the cII-dependent P_I promoter is responsible for λint gene expression. The only apparent counterpart to P_I in P22 is oriented in the opposite direction, and cannot transcribe the P22 int gene. We show that this promoter, called P_al, is active both in vivo and in vitro, and is dependent upon the P22 cII-like gene, called c1. We have also determined the DNA sequence of a 3.3 kb segment that closes the gap between previously reported sequences to give a continuous sequence between the P22 p_L promoter and the int gene. The newly determined sequence is densely packed with genes from the p_L direction, and the proteins predicted by the sequence show excellent correlation with the proteins mapped by Youderian and Susskind in 1980. However, the sequence contains no apparent genes in the opposite (p_al) direction, and no additional binding motifs for the P22 c1 protein. We conclude that int gene expression in P22 is regulated by a different mechanism than in λ.     

Partition of proteins in aqueous two-phase systems containing charged dextran or hydrophobic PEG

Summary The electrochemical effect of a charged dextran derivative and the hydrophobic effect of hydrophobic chain PEG derivative on partitioning of six types of proteins in PEG/dextran aqueous two-phase systems were investigated- When 1. 6%(w/w)DEAE-dextran was present in the system,the partition coefficient decreased quickly with increasing pH value;when 0. 4% (w/w)PEG pentadecanoic acid ester was present in the system, the partition coefficient of protein with strong hydrophobicity was greatly increased. The experimental results show that the influence of hydrocarbon chain PEG derivative on partition coefficient is closely related to the hydrophobicity of proteins.     

蜜蜂脑乙酰胆碱免疫反应阳性神经元的分布

通过免疫组织化学方法-PAP法,使用乙酰胆碱(ACh)抗体,研究了中华蜂(Apis sinensis)和意大利蜂(Apis mellifera L)脑中具有乙酰胆碱免疫阳性反应的神经元胞体的形态、分布及神经元类型.并和已知的在其他昆虫脑中用ACh的合成酶ChAT和其水解酶AChE的抗体免疫组化法所获得的结果进行了比较.     

New Isopropyl Chromone and Flavanone Glucoside Compounds from the Leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry and Their Inhibition of Nitric Oxide Production

A new isopropyl chromone ( 1 ) and a new flavanone glucoside ( 2 ) together with eleven known compounds ( 3–13 ) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their structures were elucidated as 5,7-dihydroxy-2-isopropyl-6,8-dimethyl-4H-chromen-4-one ( 1 ), 5,7-dihydroxyflavanone 7-O-β-D-(6′′-O-galloylglucopyranoside) ( 2 ), strobopinin ( 3 ), demethoxymatteucinol ( 4 ), pinocembrin-7-O-β-D-glucopyranoside ( 5 ), (2S)-hydroxynaringenin-7-O-β-D-glucopyranoside ( 6 ), afzelin ( 7 ), quercetin ( 8 ), kaplanin ( 9 ), endoperoxide G3 ( 10 ), grasshopper ( 11 ), vomifoliol ( 12 ), litseagermacrane ( 13 ) by the analysis of HR-ESI-MS, NMR, and CD spectral data. Compounds 1 , 2 , 5 , 6 and 10 inhibited NO production on LPS-activated RAW264.7 cells with IC₅₀ values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 μM, respectively, while the IC₅₀ values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 μM, compared to that of the positive control, N^G-monomethyl-L-arginine acetate (L-NMMA) with an IC₅₀ value of 32.50±1.00 μM.     

The Ethanol Extract of Syringa oblata Heartwood,a Mongolian Folk Medicine Containing Major Lignans,Exerts Analgesic and Sedative Effects on Mice

The heartwood of Syringa oblata Lindl. (SO) is one of Mongolian folk medicines to treat insomnia and pain, while its pharmacological evaluation and underlying mechanism remain unclear. In this study, the sedative effect of ethanol extract of SO (ESO) was evaluated with the locomotor activity test and the threshold dose of pentobarbital sodium-induced sleep test in mice, and the hot plate test, acetic acid-induced writhing test, and formalin test in mice were used to evaluate its analgesic effect. The underlying mechanism of ESO analgesia was explored by RT-PCR and western blot analysis, which is associated with the regulation of the NF-κB signaling pathway. Besides, the main constituents of ESO were characterized by LC/MS data analysis and comparison with isolated pure compounds. The current findings brought evidence for clinical application and further pharmacological and phytochemical studies on SO.     

Four New C19-Diterpenoid Alkaloids from Aconitum nagarum Stapf

Four new aconitine-type C₁₉-diterpenoid alkaloids, were isolated from the roots of Aconitum nagarum Stapf which were named as nagarutines A–D ( 1–4 ), together with eleven known compounds ( 5–15 ). The structures of the compounds were identified by IR, HR-ESI-MS, 1D and 2D NMR spectra. All compounds were tested for the inhibitory effect on LPS induced NO production in RAW 264.7 macrophages, compound 7 showed moderate anti-inflammatory activity effect and Inhibition rate is about 44.50%.