Cedars-Sinai Medical Center, Los Angeles, California, USA.
Phytother Res. 2010 Aug;24(8):1202-6. doi: 10.1002/ptr.3113.
Antibiotic resistance is increasing resulting in a decreasing number of fully active antimicrobial agents available to treat infections with multi-drug resistant (MDR) bacteria. Herbal medicines may offer alternative treatment options. A direct inoculation method simulating the standard disc diffusion assay was developed to determine in vitro antimicrobial activity of sixty herbal extracts against MDR-Acinetobacter baumannii (A. baumannii). Eighteen herbal extracts inhibited MDR-A. baumannii on agar plates, although the magnitude and quality of bacterial inhibition differed considerably among the antibacterial herbal extracts. Next, minimal inhibitory concentration (MIC) of these antibacterial herbal extracts was calculated using a broth microdilution assay. For most herbal extracts, the larger the zone of inhibition on agar plates, the lower the MIC. In general, hetero-resistance on agar plates correlated with higher MIC. The skip well phenomenon was seen with two herbal extracts. In conclusion, 30% of the screened herbal extracts demonstrated in vitro antibacterial activity against MDR-A. baumannii using similar rigorous testing methods as those commonly employed for assessing antimicrobial activity of synthetic antibacterial agents. Characterization of a specific compound conferring this antibacterial activity of the herbal extracts may help to identify novel antimicrobial agents active against highly resistant bacteria.
抗生素耐药性不断增加，导致可用于治疗多重耐药（MDR）细菌感染的完全有效的抗菌药物数量不断减少。草药可能提供替代治疗选择。开发了一种直接接种方法，模拟标准的圆盘扩散测定法，以确定 60 种草药提取物对 MDR 鲍曼不动杆菌（A.baumannii）的体外抗菌活性。有 18 种草药提取物在琼脂平板上抑制了 MDR-A.baumannii，尽管抗菌草药提取物之间的细菌抑制幅度和质量差异很大。接下来，使用肉汤微量稀释法计算这些抗菌草药提取物的最小抑菌浓度（MIC）。对于大多数草药提取物，琼脂平板上的抑菌圈越大，MIC 越低。通常，琼脂平板上的异耐药性与较高的 MIC 相关。两种草药提取物出现跳过孔现象。总之，使用与评估合成抗菌剂抗菌活性常用的类似严格的测试方法，筛选出的 30%的草药提取物对 MDR-A.baumannii 具有体外抗菌活性。鉴定赋予草药提取物这种抗菌活性的特定化合物可能有助于识别对抗高度耐药细菌有效的新型抗菌剂。
