Dey Diganta, Ray Ratnamala, Hazra Banasri
Department of Pharmaceutical Technology, Jadavpur University , Kolkata, West Bengal , India and.
Pharm Biol. 2015;53(10):1474-80. doi: 10.3109/13880209.2014.986687. Epub 2015 Apr 10.
The global surge in multi-drug resistant bacteria and the imminence of tuberculosis pandemic necessitate alternative therapeutic approaches to augment the existing medications. Pomegranate, the fruit of Punica granatum Linn. (Punicaceae), widely recognized for potency against a broad spectrum of bacterial pathogens, deserves further investigation in this respect.
This study determines the therapeutic potential of pomegranate juice, extracts of non-edible peel prepared with methanol/water, and its four polyphenolic constituents, namely caffeic acid, ellagic acid, epigallocatechin-3-gallate (EGCG) and quercetin, against drug-resistant clinical isolates.
Phenotypic characterisation of Mycobacterium tuberculosis, extended-spectrum β-lactamase (ESBL) and KPC-type carbapenemase producing Klebsiella pneumoniae was performed by biochemical and molecular methods. Resistance profiles of M. tuberculosis and K. pneumoniae were determined using LJ proportion and Kirby-Bauer methods, respectively. Pomegranate fruit extracts, and the compounds, were evaluated at a dose range of 1024-0.5 µg/mL, and 512-0.25 µg/mL, respectively, to determine minimum inhibitory (MIC) and bactericidal concentrations (MBC) against the drug-resistant isolates by the broth micro-dilution method.
The peel extracts exhibited greater antimycobacterial activity (MIC 64-1024 μg/mL) than the potable juice (MIC 256 - > 1024 μg/mL). EGCG and quercetin exhibited higher antitubercular (MIC 32-256 μg/mL) and antibacterial (MIC 64-56 μg/mL) potencies than caffeic acid and ellagic acid (MIC 64-512 μg/mL).
The pomegranate fruit peel and pure constituents were active against a broad panel of M. tuberculosis and β-lactamase producing K. pneumoniae isolates. EGCG and quercetin need further investigation for prospective application against respiratory infections.
全球多重耐药菌的激增以及结核病大流行的紧迫性，使得需要替代治疗方法来补充现有药物。石榴，即石榴科石榴属植物石榴（Punica granatum Linn.）的果实，因其对多种细菌病原体具有抗菌活性而广为人知，在这方面值得进一步研究。
本研究确定石榴汁、用甲醇/水制备的不可食用果皮提取物及其四种多酚成分，即咖啡酸、鞣花酸、表没食子儿茶素-3-没食子酸酯（EGCG）和槲皮素，对耐药临床分离株的治疗潜力。
通过生化和分子方法对结核分枝杆菌、产超广谱β-内酰胺酶（ESBL）和KPC型碳青霉烯酶的肺炎克雷伯菌进行表型鉴定。分别采用LJ比例法和 Kirby-Bauer法测定结核分枝杆菌和肺炎克雷伯菌的耐药谱。采用肉汤微量稀释法，分别在1024 - 0.5 μg/mL和512 - 0.25 μg/mL的剂量范围内评估石榴果实提取物及其化合物，以确定对耐药分离株的最低抑菌浓度（MIC）和杀菌浓度（MBC）。
果皮提取物表现出比可饮用果汁更强的抗分枝杆菌活性（MIC 64 - 1024 μg/mL）（可饮用果汁的MIC为256 - >1024 μg/mL）。EGCG和槲皮素表现出比咖啡酸和鞣花酸（MIC 64 - 512 μg/mL）更高的抗结核活性（MIC 32 - 256 μg/mL）和抗菌活性（MIC 64 - 56 μg/mL）。
石榴果皮及其纯成分对多种结核分枝杆菌和产β-内酰胺酶的肺炎克雷伯菌分离株具有活性。EGCG和槲皮素在抗呼吸道感染方面的潜在应用需要进一步研究。
