Urine from sheep fed with different plantain cultivars (Plantago lanceolata L.) was characterised to determine if metabolites in the urine contributed to soil biological nitrification inhibition (BNI) activity. Chromatographic analyses, combined with mass spectrometry, revealed there were more than 800 mass features that were unique to, or present in much greater concentration, in urine from sheep fed plantain than in urine of ryegrass (Lolium perenne L.)-fed sheep. The plantain metabolites aucubin, verbascoside, and catalpol have been implicated in relation to BNI activity, but these compounds were not detected in the urine of sheep fed with plantain. However, based on the mass spectral fragmentation patterns, metabolic derivatives of these compounds were present. A series of incubation studies showed that short-term nitrification inhibition did occur when plantain urine was applied to soil. Inhibition depended on several factors, including length of plantain grazing period and plantain cultivar type. As the incubations progressed, the inhibitory effect declined, potentially because of degradation of the inhibitory compounds by soil microorganisms. Urine of sheep fed with the plantain cultivar ‘Agritonic’ had a particularly strong inhibitory effect, which persisted for more than 1 month at an incubation temperature of 20 °C. Furthermore, in a laboratory bioassay using a pure culture of ammonia-oxidising bacteria, the organic fraction of urine from sheep fed with ‘Agritonic’ plantain was shown to be a strong nitrification inhibitor. This work suggests that valuable environmental benefits can be obtained by including cultivars of plantain showing BNI activity in pastures.

用不同的车前草品种 ( Plantago lanceolata L.)喂养的绵羊的尿液进行了表征，以确定尿液中的代谢物是否有助于土壤生物硝化抑制 (BNI) 活性。色谱分析结合质谱分析显示，与黑麦草（Lolium perenne）的尿液相比，喂食车前草的绵羊的尿液中有 800 多种质量特征是独一无二的，或以更高的浓度存在。L.)-喂养的羊。车前草代谢物桃叶珊瑚苷、毛蕊花苷和梓醇与 BNI 活性有关，但在喂食车前草的绵羊的尿液中未检测到这些化合物。然而，基于质谱碎片模式，存在这些化合物的代谢衍生物。一系列孵化研究表明，将车前草尿液施用于土壤时确实会发生短期硝化作用。抑制取决于几个因素，包括车前草放牧期的长度和车前草品种类型。随着培养的进行，抑制作用下降，这可能是因为土壤微生物降解了抑制化合物。用大蕉品种“Agritonic”喂养的绵羊的尿液具有特别强的抑制作用，在 20 °C 的孵化温度下持续 1 个月以上。此外，在使用氨氧化细菌的纯培养物进行的实验室生物测定中，来自喂食“Agritonic”车前草的绵羊尿液的有机部分被证明是一种强硝化抑制剂。这项工作表明，通过包括在牧场显示 BNI 活性的车前草栽培品种可以获得宝贵的环境效益。