Shah Syed Hussain, Liu Hsien, Khan Muddasir, Muhammad Riaz, Qadeer Abdul, Fouad Dalia, Chen Chien-Chin
Department of Health and Biological Sciences, Abasyn University Peshawar, Peshawar, Pakistan.
Division of General Surgery, Department of Surgery, Ditmanson Medical Foundation, Chia-yi Christian Hospital, Chiayi, Taiwan.
PLoS One. 2024 Sep 16;19(9):e0300979. doi: 10.1371/journal.pone.0300979. eCollection 2024.
As the effectiveness of current treatments against the development of antimicrobial resistance is declining, new strategies are required. A great source of novel secondary metabolites with therapeutics effects are the endophytic bacteria present in medicinal plants. In this study, Klebsiella aerogenes (an endophytic bacteria belonging to the Enterobacteriaceae family) was isolated from Kalanchoe blossfeldiana (a medicinal plant". The bacterial secondary metabolites were identified using GC-MS techniques. Furthermore, the antibacterial potentials were investigated against multi-drug resistance (MDR) Salmonella typhi and Staphylococcus aureus. The GC-MS chromatogram of K. aerogenes secondary metabolites extract displayed total of 36 compounds. Ethyl acetate extracts of K. aerogenes, showed mean zone of growth inhibition of 15.00 ± 1.00 against S. typhi and 7.00 ± 1.00mm against S. aureus, respectively. The extract demonstrated significant antibacterial effectiveness against S. typhi and moderate antibacterial efficacy against S. aureus, with minimum inhibitory concentration (MIC) values ranging from 0.089 to 0.39 mg/mL. The time-kill kinetics profile of the ethyl acetate extract against S. typhi revealed a decrease in the number of viable cells during the initial 5, 6, and 24 hours. Conversely, there was a sudden increase in viable cells up to 6 hours for S. aureus. The identified secondary metabolite with high percentage than others, benzeneethanamine exhibited favorable interactions (-7.2 kcal/mol) with the penicillin-binding protein (PBP2a) of S. aureus and (-7.5 kcal/mol) osmoporin (OmpC) of S. typhi, indicating its potential as a candidate for drug development against these MDR bacteria. This study reported for the first time, bacterial endophytes associated with K. blossfeldiana with antibacterial activities.
由于当前治疗方法对抗菌素耐药性发展的有效性正在下降，因此需要新的策略。药用植物中存在的内生细菌是具有治疗作用的新型次生代谢物的重要来源。在本研究中，产气克雷伯菌（一种属于肠杆菌科的内生细菌）从长寿花（一种药用植物）中分离出来。使用气相色谱 - 质谱联用（GC-MS）技术鉴定细菌次生代谢物。此外，研究了其对多重耐药（MDR）伤寒沙门氏菌和金黄色葡萄球菌的抗菌潜力。产气克雷伯菌次生代谢物提取物的GC-MS色谱图显示共有36种化合物。产气克雷伯菌的乙酸乙酯提取物对伤寒沙门氏菌的平均生长抑制圈为15.00±1.00，对金黄色葡萄球菌的平均生长抑制圈为7.00±1.00毫米。该提取物对伤寒沙门氏菌显示出显著的抗菌效果，对金黄色葡萄球菌显示出中等抗菌效果，最低抑菌浓度（MIC）值范围为0.089至0.39毫克/毫升。乙酸乙酯提取物对伤寒沙门氏菌的时间 - 杀菌动力学曲线显示，在最初的5、6和24小时内活细胞数量减少。相反，金黄色葡萄球菌的活细胞在6小时内突然增加。鉴定出的次生代谢物中，苯乙胺的含量高于其他物质，它与金黄色葡萄球菌的青霉素结合蛋白（PBP2a）显示出良好的相互作用（-7.2千卡/摩尔），与伤寒沙门氏菌的渗透孔蛋白（OmpC）显示出良好的相互作用（-7.5千卡/摩尔），表明其作为针对这些多重耐药细菌的药物开发候选物的潜力。本研究首次报道了与长寿花相关的具有抗菌活性的细菌内生菌。
