Rafsanjany Nasli, Sendker Jandirk, Lechtenberg Matthias, Petereit Frank, Scharf Birte, Hensel Andreas
University of Münster, Institute of Pharmaceutical Biology and Phytochemistry, Corrensstrasse 48, D-48149 Münster, Germany.
University of Münster, Institute of Pharmaceutical Biology and Phytochemistry, Corrensstrasse 48, D-48149 Münster, Germany.
Fitoterapia. 2015 Sep;105:246-53. doi: 10.1016/j.fitote.2015.07.014. Epub 2015 Jul 22.
The dried stigmata from Zea mays L. are used traditionally for the treatment of uncomplicated urinary tract infections. A recent screening has indicated that hydroalcoholic extract of the herbal material inhibits the adhesion of uropathogenic Escherichia coli (UPEC) to T24 bladder cells. For verification of these data EtOH-water (1:1) extracts from 4 different batches of Maydis stigmata were investigated. Within an in vitro adhesion assay (UPEC strain 2980 and human T24 bladder cells) a dose-dependent antiadhesive activity against UPEC was verified (IC50 1040μg/mL). Bioassay guided fractionation of M. stigmata, batch S1, by EtOH-water extraction, followed by chromatography on Sephadex LH20 revealed two active fractions (I and XI). Further purification of fraction I and structure elucidation of the isolated compound revealed the presence of significant amounts of the biocide benzethonium chloride as contaminant. Benzethonium chloride was also identified in subsequent investigations in 2 different batches of M. stigmata. The presence of such nondeclared and illegal contaminants in the herbal raw material market has to be discussed intensively. From benzethonium-free raw material (batch S2) as well as from batch S1 fraction XI was further fractionated by MPLC and preparative HPLC, leading to a still complex subfraction XIG, which was analyzed by UHPLC/+ESI-QTOF-MS analysis. Advanced data processing and species-metabolite relationship database revealed the tentatively existence of the unusual C-glycosidic flavones derhamnosylmaysin (6), 3'-deoxyrhamnosylmaysin (4), 3'-O-methylderhamnosylmaysin (3), apiferol (2) and alternanthin (8) which might be related to the antiadhesive activity of this subfraction against UPEC.
玉米（Zea mays L.）的干燥柱头在传统上用于治疗单纯性尿路感染。最近的一项筛选表明，该草药材料的水醇提取物可抑制尿路致病性大肠杆菌（UPEC）对T24膀胱细胞的黏附。为了验证这些数据，对来自4个不同批次玉米柱头的乙醇-水（1:1）提取物进行了研究。在体外黏附试验（UPEC菌株2980和人T24膀胱细胞）中，证实了对UPEC具有剂量依赖性的抗黏附活性（IC50为1040μg/mL）。通过乙醇-水提取对S1批次的玉米柱头进行生物测定导向的分级分离，随后在Sephadex LH20上进行色谱分离，得到两个活性级分（I和XI）。对级分I的进一步纯化和分离化合物的结构解析表明，存在大量作为污染物的杀生物剂苄索氯铵。在随后对2个不同批次玉米柱头的研究中也鉴定出了苄索氯铵。草药原料市场中此类未申报和非法污染物的存在必须进行深入讨论。从不含苄索氯铵的原料（S2批次）以及S1批次的XI级分通过MPLC和制备型HPLC进一步分级分离，得到仍然复杂的亚级分XIG，通过UHPLC/+ESI-QTOF-MS分析对其进行了分析。先进的数据处理和物种-代谢物关系数据库初步揭示了异常的C-糖苷黄酮类化合物鼠李糖基玉米黄素（6）、3'-脱氧鼠李糖基玉米黄素（4）、3'-O-甲基鼠李糖基玉米黄素（3）、芹菜素（2）和互生花素（8）的存在，这些化合物可能与该亚级分对UPEC的抗黏附活性有关。
