酶法浸提枸杞的研究

通过对外源酶酶解枸杞效果的研究，结果表明：外源酶能显著提高枸杞浸提液中可溶性固形物和营养成分的含量，其单一纤维素酶和木瓜蛋白酶浸提枸杞的适宜pH值分别是5．0～5．5和pH值6．0，适宜的酶质量浓度分别为0．20g／dL和0．40～0．60g／dL，温度分别为55．C和65℃，适宜时间都为50-60min；两种酶组合浸提枸杞的较适pH值、温度、时间和酶组合分别为pH值5．5～6．0，55-60℃．50min和0．20g／dL纤维素酶＋0．40g／dL木瓜蛋白酶。     

永瓣藤化学成分的研究

永瓣藤化学成分的研究陈玲，谢平，戚薇，曾菊珍（药学系中药化学教研室）关键词永瓣藤，化学成分，三萜，蒜盘子甾酮永瓣藤（ＭｏｎｉｍｏｐｅｔａｌｎｍＣｈｉｎｅｎｓｅＲｅ－ｈｄ）系卫矛科永瓣藤属植物［１］，为我国特有的珍稀二类保护植物［２］，分布于江西东北部...     

Molecular analysis of streptogramin resistance in enterococci

The new semi-synthetic streptogramin antibiotic combination quinupristin/dalfopristin (Synercid) is a promising alternative for a treatment of infections with multiple resistant gram-positive pathogens, e.g. glycopeptide- and multi-resistant Enterococcus faecium. Streptogramins consist of two unrelated compounds, a streptogramin A and B, which act synergistically when given in combination. Mechanisms conferring resistance against both components are essential for resistance against the combination in E. faecium. In this species resistance to streptogramin A compounds is mediated via related acetyltransferases VatD and VatE. Resistance against streptogramins B is either encoded by the widespread ermB gene cluster conferring resistance to macrolide-lincosamide-streptogramin B antibiotics or via expression of the vgbA gene, which encodes a staphylococcal-type lactonase. E. faecalis is intrinsically resistant to streptogramins. Due to a wide use of streptogramins (virginiamycins S/M) in commercial animal farming a reservoir of streptogramin-resistant E. faecium isolates had already been selected. Determinants for streptogramin resistance are localized on plasmids that can be transferred into an E. faecium recipient both in vitro in filter-matings and in vivo in the digestive tracts of rats. Hybridization and sequencing experiments revealed a linkage of resistance determinants for streptogramins A and B on definite plasmid fragments.     

Protective effect of pinocembrin from Penthorum chinense Pursh on hepatic ischemia reperfusion injury via regulating HMGB1/TLR4 signal pathway

Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H₂O₂-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H₂O₂ group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway.     

北柴胡中黄酮类化合物的分离鉴定

研究北柴胡的化学成分。方法 :用色谱法和波谱解析方法对北柴胡根的化学成分进行分离和结构鉴定。结果 :共得到 8个化合物 :柴胡色原酮酸 (1) ,芦丁 (2 ) ,槲皮素 (3) ,异鼠李素 (4 ) ,异鼠李素 3 O 葡萄糖甙(5 ) ,葛根素 (6 ) ,7,4′ 二羟基 异黄酮 7 O β D 葡萄糖甙 (7) ,色氨酸 (8)。 结论 :化合物 1为新的天然产物 ,其余化合物均为首次从北柴胡中获得。     

鹅绒藤浸膏对麻醉大鼠的降压作用

目的：探讨鹅绒藤水溶性浸膏（AECC）对麻醉大鼠血压的影响及机制。方法：采用麻醉大鼠急性降压实验,观察iv阿托品、去甲肾上腺素,切断双侧迷走神经对AECC降压作用的影响。结果：（1）AECC有明显的降压作用。（2）阿托品不影响AECC的降压作用。（3）切断双侧迷走神经不影响AECC的降压幅度。（4）AECC不影响NA的升压作用。结论：AECC有明显的降压作用,此种作用不受阿托品的影响,与副交感系统无直接的关系,也不是通过阻断α受体或抑制血管运动中枢实现,可能是对血管心脏的直接作用。大剂量0．8g/kg iv AECC使心率减慢,P－P间期延长。     

枸杞对辐射损伤小鼠造血功能恢复的影响

目的：观察枸杞对辐射损伤小鼠造血功能恢复的影响。方法：用１００％枸杞浸出液给小白鼠灌胃５ｄ后,用＾６０钴照射３０ｓ,剂量为３０ｃＧｙ,每日１次,共５次。检测骨髓细胞增殖反应、白细胞介素－１（ＩＬ－１）和白细胞（ＷＢＣ）。结果：枸杞组骨髓细胞增殖反应增强,ＷＢＣ明显升高,与照射组相比有非常显著性差异（Ｐ〈０．０１）。结论：枸杞对辐射损伤小鼠有促进骨髓细胞增殖及ＷＢＣ升高的作用。     

高效液相色谱法测定关黄柏不同采收期及黄檗不同部位的小檗碱、巴马汀含量

目的测定关黄柏不同采收期及黄檗不同部位的小檗碱、巴马汀的含量。方法采用高效液相色谱法测定。结果检测波长 345nm ,平均加样回收率分别为 96 9%和 97 2 % ,RSD =0 5 7%和0 6 2 %。结论沈阳地区关黄柏的最佳采收期为 10月 ;黄檗枝条中的小檗碱含量虽不及关黄柏 ,但枝条为再生资源     

小叶石楠的化学成分研究

目的 研究小叶石楠茎的化学成分。方法 采用硅胶色谱法分离纯化，薄层色谱及波谱法进行结构鉴定。结果 从其乙醇提取物的氯仿、醋酸乙酯部分分得7个化合物，其结构鉴定为羽扇豆醇(Ⅰ)，β-谷甾醇(Ⅱ)，白桦酸(Ⅲ)，pyracrenic acid(Ⅳ)，表儿茶素(V)，胡萝卜苷(Ⅵ)，野樱苷(Ⅶ)。结论 化合物Ⅰ，Ⅲ～Ⅵ为首次从该属植物中分离得到，化合物Ⅲ和Ⅶ为首次从该植物中分离得到。化合物Ⅳ具有抗肿瘤活性。     

枸杞的染色体核型分析

对野生枸杞及其栽培品种大叶枸杞的染色体核型进行了研究,二者12号染色体均具随体。前者染色体数目为24,是二倍体,核型为1B型,核型公式为2n=2x=24=18m+6sm;后者染色体数目为48,是四倍体,核型为2B型,核型公式为2n=4x=48=36m+12sm。