Effect of Manganese on DNA-Protein Crosslinks of Testicle in Chicken

In order to explore the effect of manganese on DNA-protein crosslinks （DPC） of testicle in chicken. 500, 800, 1 700 mg·kg^-1 MnC12 were added to forage to establish the model of the sub-chronic manganese poisoning. After 30, 60 and 90 d, testicles were taken out to detect hydroxyl radical inhibiting capacity and DPC content. The results showed that compared with control group, hydroxyl radical inhibiting capacity significantly decreased and DPC content notably increased, and there was a time-dose relationship. It demonstrated that manganese could decrease the inhibitng capacity of hydroxyl radical, increase the content of hydroxyl and DPC, and induce DNA damage.     

海带废渣真姬菇发酵产物抗氧化活性研究

为了开发海带废渣资源化利用的新途径,以真姬菇为供试菌株,对海带废渣进行液体发酵,并研究发酵产物的抗氧化活性。结果表明真姬菇能以海带渣为营养基质,进行生长发酵,并产生有效的抗氧化活性物质。抗氧化试剂盒检测显示发酵上清液总抗氧化活性为0.23±0.02 U/mg,比未发酵的海带废渣高43.8%,其发酵产物提取液的总抗氧化活性为0.77±0.01 U/mg,比未发酵的海带废渣高18.5%,且均高于化学抗氧化剂BHT。发酵上清液还具有良好的羟自由基清除能力（EC50=0.43 mg/mL）和一定的超氧阴离子自由基清除能力（EC50=26.02 mg/mL）。分析结果表明发酵过程中产生的抗氧化活性物质主要存在于菌丝体内部,而具有羟自由基清除能力的活性物质则游离于发酵上清液。     

Evaluation of antioxidant activities of the edible and medicinal Suaeda species and related phenolic compounds

Antioxidants are the chemical substances that reduce or prevent oxidation. The present study aimed to assess in vitro and ex vivo antioxidant activities of four acetonic extracts Tunisian halophytes (Suaeda fruticosa, Suaeda pruinosa, Suaeda mollis and Suaeda maritima). Various experimental models were used for characterization of antioxidant activities of shoot extracts. Eventually, the promising specie was subjected to phenolic identification using RP-HPLC. The analyzed shoot extracts exhibited that antioxidant activities varied considerably as function of species. The highest DPPH scavenging ability was found in S. mollis with the lowest IC₅₀ value (2.5 μg/ml), followed by S. pruinosa, S. fruticosa and S. maritima. The same tendency was observed with ferric reducing power. Concerning β-carotene bleaching assays and total antioxidant activity, results showed that S. fruticosa exhibited the highest antioxidant ability against the inhibition of β-carotene bleaching, and a better total antioxidant capacity. Moreover antioxidant capacities using ORAC method and a cell based-assay showed that S. mollis, S. fruticosa, and S. pruinosa exhibit statistically similar antioxidant activity. The identification of phenolic compounds in S. mollis extract using RP-HPLC revealed that 2,5-dihydroxybenzoic acid and rutin hydrate were the major molecules. These results suggested that Suaeda species showed a variability of their antioxidant activities.     

珙桐叶水提物的抗氧化性能

通过测定珙桐叶水提物粗品及其乙酸乙酯分部和水分部的还原能力、清除羟自由基和超氧阴离子自由基的能力来研究其抗氧化性能.结果显示,100 μg珙桐叶水提物乙酸乙酯分部的还原能力与60 μg V-C相当,其清除羟自由基的IC50值为V-C的2倍,但清除超氧阴离子自由基的能力较弱.珙桐叶水提物粗品及其乙酸乙酯分部和水分部的还原能力、清除羟自由基的能力与其多酚含量呈正相关.     

Experimental study on nitrobenzene by cavitating water jets assisted with Fenton

Nitrobenzene compounds,featured with weak mutagenicity,chemical stability,are difficult to be purified by traditional degradation method.Several factors involved in the nitrobenzene wastewater degradation are comparatively analyzed by cavitating water jets assisted with Fenton.The removal ratio of nitrobenzene,whose concentration is 50 mg/L,reaches 95.06% when the Fe2+ concentration is 40 mg/L,the pH value,5.0,the hydrogen peroxide concentration,150 mg/L,the confining pressure,0.5 MPa,and the jetting pressure,10 MPa.The degradation mechanism,shown by high performance liquid chromatography (HPLC),is that the cavitating water jet impelled the Fenton to release more HO· and enhances the catalytic capacity of Fe2+,then the nitrobenzene is degraded or oxidized totally,or graded into small organic molecules such as chain hydrocarbon and organic acids,etc.Besides,the intermediate products,including Benzoquinone,4 Nitrophenol,2 Nitrophenol and Hydroquinone,are also shown by HPLC.     

通过泰乐内酯羟基的选择性氧化改进泰地罗新合成工艺

泰地罗新是一种新型泰乐菌素类抗生素，其特征是将泰乐菌素内酯C20,23的取代基用哌啶取代。本研究为解决C23羟基氨化反应难度较高的问题，通过TEMBO选择性氧化,将泰乐内酯23位羟基氧化为羰基。再与哌啶进行Wallach反应，以合成泰地罗新。该路线规避了C23羟基碘化过程成本高、反应得率低的问题，反应平均总摩尔收率90.11%，终产物含量971 mg/g。