Intracellular bioactivity of macrolides

A brief overview is provided of the bioactivity of macrolides against a range of bacterial species. Topics considered include the cellular pharmacokinetics of uptake and efflux of these drugs and the importance of intra- or extracellular and cytoplasmic or granular location on their activity. Emphasis is placed on the importance of synergy between macrolides and host defenses, with drug accumulation producing modification of cellular function, such as enhancement of phagocytosis, and exocytosis of polymorphonuclear neutrophils. Such interaction may explain the activity of such agents against organisms which normally inhibit fusion of phagolysosomes.     

茶叶多糖的研究进展

茶叶多糖是一种复合杂多糖，具有许多生物活性。作者系统地介绍了茶叶多糖的提取、分离、纯化、纯度鉴定及相对分子质量测定的方法，以及其含量和组成、理化性质、化学结构及空间构象、生物活性等方面的研究进展，并对上述方法及研究进展进行了分析和评述。     

人参皂苷Rd的研究进展

人参皂苷Rd是二醇型人参皂苷在人体肠道内的主要代谢产物之一,具有广泛的生物活性.对心脑血管、神经系统、免疫系统等作用独特;在镇痛、神经保护作用方面,人参皂苷Rd相对于其他单体皂苷也较强.人参皂苷Rd的结构复杂,化学合成至今尚未成功,需从植物药中提取以满足医疗和科研的需要,但因植物中人参皂苷Rd的量较低,从植物中提取的方法 难以满足需要.因此,国内外在有效获取人参皂苷Rd方面也进行了大量研究.对人参皂苷Rd的生物活性、制备方法 等研究进行了详细综述.     

长毛香科科化学成分及生物活性研究

目的:研究长毛香科科化学成分及生物活性.方法:采用各种色谱法分离,运用多种波谱技术和X-衍射鉴定结构;利用体外DPPH微量抗氧化模型、α-葡萄糖苷酶抑制模型和纸片扩散法进行抑菌活性筛选.结果:从长毛香科科醋酸乙酯部位分离鉴定了8个化合物:三(十八酸)甘油酯(1),2,5-二氧环戊酮(2),羊齿烯醇(3),△~(5,22)-豆甾烯醇(4),24-去亚甲胆甾-5,22(E)-二烯-3β-醇(5),α-菠菜甾醇(6),3,4-二羟基苯丙烯酸乙二醇单酯(7),3,4-二羟基苯丙烯酸(8).结论:化合物1～8为首次从该属中分离得到.生物活性测试结果表明化合物3[IC_(50)=(37.63±3.45)mg·L~(-1)],6[IC_(50)=(178.92±4.99)mg·L~(-1)]和8[IC_(50)=(44.32±7.02)mg·L~(-1)]体外抑制α-糖苷酶抑制活性远高于对照acarbose[IC_(50)=(1 081.27±12.3)mg·L~(-1)];化合物7[IC_(50)=(4.81±0.96)mg·L~(-1)]和8[IC_(50)=(4.16±0.11)mg·L~(-1)]抗氧化活性高于对照BHT[IC_(50)=(35.64±0.36)mg·L~(-1)]和BHA[IC_(50)=(8.74±0.39)mg·L~(-1)];化合物5～8均对小麦赤霉病有明显的抑制活性;化合物5和8对番茄灰霉病菌有明显抑制效果.     

Inhibitory effect of plasma obtained from hypophysectomized and control women on the assay of bioactive luteinizing hormone

The purpose of this study was to determine the effect of components of female plasma on the value of bioactive luteinizing hormone (LH), especially in the presence of low immunological LH value. Using both an immunoradiometric assay (IRMA) and rat Leydig cell bioassay, immunoreactive (I) and bioactive (B) LH were assessed in plasma collected from women during a gonadotrophin releasing hormone (GnRH) test performed on day 7 of a spontaneous cycle. Two modes of response to an acute administration of GnRH were defined: normal production of gonadotrophins (group I) and excessive secretion (group II) associated with a significant difference in the B/I-LH ratio between the two groups. The B/I-LH ratio did not vary with sampling time during the test in either group. The addition of LH-free plasma collected from hypophysectomized women caused a 30% decrease in testosterone production compared to control values (in the presence or absence of hLH standard). A partial restoration of testosterone production was observed if plasma was first treated with PEG 12%. The inhibitory factor(s) was also present in plasma from ovulatory women, even after treatment by an antibody against the entire LH molecule. The effect of normal (A) or low I-LH plasma (B) on testosterone production varied strongly according to the plasma volume added to the bioassay, as well as to plasma treatments. Diethylether treatment caused a 50% decrease in testosterone secretion for plasma B (but not for A) whereas a diminution of the steroidogenesis is observed after a PEG treatment of plasma A (but not for B), suggesting that different inhibitory factors are present in plasmas A and B. Therefore the LH bioactivity measured in the rat Leydig cell assay, in terms of testosterone output, seems to represent a balance between the LH molecule and the presence of inhibitory factors in the plasma.     

广藿香内生真菌撕裂耙齿菌A878次级代谢产物研究

目的 研究药用植物广藿香Pogostemon cablin内生真菌撕裂耙齿菌Irpex laceratus A878的活性次级代谢产物。方法 运用硅胶、Sephadex LH-20、HPLC等多种柱色谱技术以及重结晶方法对发酵产物进行分离纯化,并利用¹H-和¹³C-NMR、UV等谱学方法鉴定化合物结构。采用SRB法和Griess法测定化合物的生物活性。结果 从广藿香内生真菌撕裂耙齿菌A878固体发酵产物中分离鉴定了2个新化合物和10个已知化合物。分别为撕裂耙齿菌内酯A(1)、撕裂耙齿菌内酯B(2)、细胞松弛素H(3)、细胞松弛素J(4)、18-甲氧基细胞松弛素J(5)、去乙酰基细胞松弛素H(6)、细胞松弛素J₃(7)、拟茎点霉(口山)酮A(8)、狄瑟酚A(9)、桔青霉三酚A(10)、(22E,24R)-麦角甾-5,7,22-三烯-3β-醇(11)和1S,2R,4S-三羟基-对-薄荷烷(12)。结论 化合物1、2为新的吡喃内酯类化合物。活性研究表明化合物4、5和9对人神经癌SF-268细胞、人乳腺癌MCF-7细胞、人肝癌H...     

基于小鼠子宫平滑肌收缩活性测定的桂枝茯苓胶囊质量评价研究

目的 从桂枝茯苓胶囊（Guizhi Fuling Capsules,GZFLC）临床用于治疗痛经的功效出发,探索建立基于子宫平滑肌收缩活性测定的GZFLC质量生物活性评价方法。方法 通过注射雌激素增加小鼠子宫敏感性,建立缩宫素诱导的小鼠离体子宫平滑肌收缩模型,采集给药前后小鼠子宫平滑肌的收缩频率、幅值和峰面积,以收缩峰面积为指标进行统计并对药效进行归一化处理。考察小鼠离体子宫平滑肌收缩模型的主要影响因素如雌激素注射方式与天数、缩宫素浓度、动物周龄和GZFLC前处理方法。建立GZFLC质量生物活性评价方法并进行方法学考察,测定10个批次GZFLC合格样品及2个GZFLC高温破坏样品的生物活性。结果 连续3 d ip雌激素10 mg/（kg·d）后小鼠子宫平滑肌收缩峰面积较高且收缩节律较好;最适缩宫素造模质量浓度为0.050 μg/mL;将GZFLC配制成质量浓度为0.125 g/mL的药液并超声溶解60 min有利于药效发挥;重复性考察RSD为11.298%,日内精密度RSD为12.452%,日间精密度RSD为10.438%;10批次GZFLC半数抑制浓度（half inhibitory concentration,IC₅₀）为1.526～1.631 mg/mL,高温破坏后GZFLC的IC₅₀明显增大。结论 基于子宫平滑肌收缩活性测定的GZFLC质量评价方法重复性和精密度较好,为后续GZFLC的综合质量评价标准建立提供了科学依据。     

多肽药物分析方法研究进展

介绍多肽药物的生物活性分析、结构分析、纯度分析的发展状况。     

大肠杆菌T蛋白PDH结构域的高效表达纯化与活性测定

 目的构建高效表达菌株,以大量表达大肠杆菌T蛋白的预苯酸脱氢酶(PDH),为研究T蛋白双功能结构域CM和PDH的相互协同作用以及T蛋白抑制剂对其影响提供活性蛋白材料。方法利用pGEX高效融合表达系统将PDH与谷光甘肽疏基转移酶(GST)编码序列在表达宿主BL21实现高效表达,并利用对GST具有亲和作用的GlutathioneSepharose4B琼脂糖珠进行亲和层析以对其分离纯化。结果表达产物达菌体总蛋白的40%,可溶性目的产物得量为240mg·L^-1,利用亲和层析法纯化后纯度达92.5%,GSTPDH融合蛋白的PDH的比活为38U·mg^-1。结论本法成功构建高效表达PDH菌株,表达量高,纯化度高,GST-PDH酶活性正常,为进一步研究奠定基础。     

Halichondria属软海绵次生代谢产物及其生物活性

Halichondria属软海绵分布广泛,含多种生物活性成分,引起人们的深入研究。近30年来,已从Halichon-dria属软海绵中分离得到了许多结构新颖,有抗菌、抗肿瘤和抗病毒等生物活性的次生代谢产物,如大环内酯、聚醚、生物碱、内酰胺、萜类、甾醇、鞘类脂糖苷等。在调研国内外相关资料的基础上,按化合物的结构类型简要介绍了1978—2003年Halichondria属软海绵次生代谢产物及其生物活性的研究概况,为进一步的研究工作提供参考。