Medicinal and Aromatic Plants Research Department, National Research Centre, Dokki, Giza, 12622, Egypt.
Chemistry of Natural Compounds Department, National Research Centre, Dokki, Giza, 12622, Egypt.
Inflammopharmacology. 2019 Apr;27(2):373-385. doi: 10.1007/s10787-018-0547-0. Epub 2018 Nov 16.
Ankylosing spondylitis, multiple sclerosis, rheumatoid arthritis and rheumatic fever are autoimmune inflammatory diseases that may be triggered in genetically susceptible individuals by specific bacterial pathogens. Inhibiting the growth of these bacteria with high antioxidant plant extracts may inhibit the aetiology of these diseases, as well as inhibiting the later phase symptoms. P. squarrosa extracts were analysed for antioxidant activity using a DPPH free radical scavenging assay. Bacterial growth inhibitory activity was evaluated using disc diffusion assays and the activity was quantified by MIC determination. The extracts were screened for toxicity by A. franciscana nauplii assays. The most potent antibacterial extract (ethyl acetate) was analysed by GC-MS headspace profile analysis and compounds were identified with reference to a phytochemical database. All extracts displayed strong DPPH radical scavenging activity. The ethyl acetate extract was particularly potent (IC 1.4 µg/mL), whilst the other extracts also had significant radical scavenging activity (IC values between 11 and 22 µg/mL). Notably, the bacterial growth inhibitory activity of the extracts correlated with their DPPH radical scavenging activity. The ethyl acetate extract, which had the greatest DPPH scavenging activity, generally displayed the most potent bacterial growth inhibitory activity. This extract was particularly potent against P. mirabilis, P. vulgaris and A. baylyi (MIC values of 484, 575 and 880 µg/mL, respectively). It also inhibited P. aeruginosa and S. pyogenes growth, albeit with higher MICs (1600-3700 µg/mL). All other extract-bacteria combinations were either inactive or resulted in mid-low potency inhibition. All extracts were non-toxic in the A. franciscana bioassay (LC substantially > 1000 µg/mL). In total, 89 unique mass signals were identified in the P. squarrosa ethyl acetate extract by non-biased GC-MS headspace analysis. A number of compounds which may contribute to the antibacterial activity of this extract have been highlighted.
强直性脊柱炎、多发性硬化症、类风湿性关节炎和风湿热是自身免疫性炎症性疾病，在遗传易感性个体中，这些疾病可能由特定的细菌病原体引发。用具有高抗氧化能力的植物提取物来抑制这些细菌的生长，可能不仅可以抑制这些疾病的病因，还可以抑制后期的症状。本研究采用 DPPH 自由基清除测定法分析了皱叶酸模的抗氧化活性。采用圆盘扩散法评估了抑菌活性，并通过 MIC 测定来量化活性。采用卤虫幼体法评估提取物的毒性。用 GC-MS 顶空分析对最有效的抑菌提取物（乙酸乙酯提取物）进行分析，并参考植物化学数据库来鉴定化合物。所有提取物均显示出较强的 DPPH 自由基清除活性。乙酸乙酯提取物的活性最强（IC 1.4 µg/mL），而其他提取物也具有显著的自由基清除活性（IC 值在 11 至 22 µg/mL 之间）。值得注意的是，提取物的抑菌活性与 DPPH 自由基清除活性相关。具有最大 DPPH 清除活性的乙酸乙酯提取物通常表现出最强的抑菌活性。该提取物对奇异变形杆菌、普通变形杆菌和栖水贝氏不动杆菌的抑制作用最强（MIC 值分别为 484、575 和 880 µg/mL）。它还抑制了铜绿假单胞菌和酿脓链球菌的生长，尽管 MIC 值较高（1600-3700 µg/mL）。其他提取物与细菌的组合要么没有活性，要么表现出中等或低等抑制作用。在卤虫生物测定中，所有提取物均无毒性（LC 值远大于 1000 µg/mL）。通过非靶向 GC-MS 顶空分析，在皱叶酸模的乙酸乙酯提取物中共鉴定出 89 个独特的质谱信号。一些可能对该提取物的抑菌活性有贡献的化合物已被突出显示。
