Institute of Transplantation and Gene Sciences, Baskent University, 06980 Ankara, Turkey.
Int J Food Sci Nutr. 2013 May;64(3):355-62. doi: 10.3109/09637486.2012.734290. Epub 2012 Oct 16.
The aim of this study was to comparatively evaluate antibacterial activities of methanol (MetOH) and aqueous (dw) leaf (L), root (R) and seed (S) extracts of Urtica dioica L. (Ud; stinging nettle) and Urtica pilulifera L. (Up; Roman nettle) on both food- and plant-borne pathogens, with total phenolic contents and DPPH radical scavenging activities (DRSA). MetOH extracts of leaves and roots of U. dioica had the highest DRSA. Extracts with high antibacterial activity were in the order Up-LMetOH (13/16) > Ud-SMetOH (11/16) > Up-SMetOH (9/16). Results obtained with Up-SMetOH against food spoiling Bacillus pumilus, Shigella spp. and Enterococcus gallinarum with minimum inhibitory concentrations (MICs) in 128-1024 μg/ml range seem to be promising. Up-SMetOH also exerted strong inhibition against Clavibacter michiganensis with a considerably low MIC (32 μg/ml). Ud-SMetOH and Up-LMetOH were also effective against C. michiganensis (MIC = 256 and 1024 μg/ml, respectively). Ud-SMetOH and Ud-RMetOH had also antimicrobial activity against Xanthomonas vesicatoria (MIC = 512 and 1024 μg/ml, respectively). Results presented here demonstrate high-antibacterial activity of U. pilulifera extracts and U. dioica seed extract against phytopathogens for the first time, and provide the most comprehensive data on the antibacterial activity screening of U. pilulifera against food-borne pathogens. Considering limitations in plant disease control, antibacterial activities of these extracts would be of agricultural importance.
本研究旨在比较评价荨麻（Urtica dioica L.，U. dioica）和小荨麻（Urtica pilulifera L.，U. pilulifera）叶（L）、根（R）和种子（S）甲醇（MetOH）和水（dw）提取物对食源性病原体和植物病原菌的抗菌活性，以及总酚含量和 DPPH 自由基清除活性（DRSA）。U. dioica 的叶和根的 MetOH 提取物具有最高的 DRSA。具有高抗菌活性的提取物依次为 U. pilulifera L. -LMetOH（13/16）>U. dioica SMetOH（11/16）>U. pilulifera SMetOH（9/16）。用 U. pilulifera SMetOH 对食品腐败菌解淀粉芽孢杆菌、志贺氏菌和鸡肠球菌进行的最低抑菌浓度（MIC）研究结果表明，其 MIC 范围在 128-1024μg/ml，似乎具有很大的潜力。U. pilulifera SMetOH 对棒状杆菌的抑制作用也很强，MIC 较低（32μg/ml）。U. dioica SMetOH 和 U. pilulifera LMetOH 对 C. michiganensis 也有效（MIC 分别为 256 和 1024μg/ml）。U. dioica SMetOH 和 U. dioica RMetOH 对 Xanthomonas vesicatoria 也具有抗菌活性（MIC 分别为 512 和 1024μg/ml）。本研究首次证明了小荨麻提取物和荨麻种子提取物对植物病原菌具有高抗菌活性，并提供了小荨麻对食源性病原体抗菌活性筛选的最全面数据。考虑到植物病害控制的局限性，这些提取物的抗菌活性将具有农业重要性。
