Department of Physics, Faculty of Science, University of Guilan, Rasht, 41335-1914, Iran.
Department of Biology, Faculty of Science, University of Guilan, Rasht, 41335-1914, Iran.
Sci Rep. 2023 Jun 9;13(1):9441. doi: 10.1038/s41598-023-35906-x.
The present study reports a significant combined antibacterial activity of Cichorium intybus L. (known as Chicory) natural extract with cold atmospheric-pressure argon plasma treatment against multi-drug resistant (MDR) Gram-negative bacteria. To detect reactive species that are generated in the argon plasma, optical emission spectra were recorded. The molecular bands were allocated to the hydroxyl radicals (OH) and neutral nitrogen molecules (N). Moreover, the atomic lines form the emitted spectra were determined to argon atoms (Ar) and the oxygen atoms (O), respectively. The results revealed that Chicory extract treatment at a concentration of 0.043 g/ml reduced the metabolic activity of P. aeruginosa cells by 42%, while, a reduced metabolic activity of 50.6% was found for E. coli biofilms. Moreover, the combination of Chicory extract with 3 min Ar-plasma introduced a synergistic effect, so that it exhibited a significantly reduced metabolic activity of P. aeruginosa to 84.1%, and E. coli ones to 86.7%, respectively. The relationship between cell viability and membrane integrity of P. aeruginosa and E. coli biofilms treated with Chicory extract and argon plasma jet were also analyzed by CLSM. It was found that after the combined treatment, a noticeable membrane disruption was formed. Besides, it was concluded that E. coli biofilms showed a higher sensitivity to Ar-plasma than P. aeruginosa biofilm at longer plasma exposure times. This study suggests that the anti-biofilm therapy based on a combined effect of Chicory extract and cold argon plasma treatment can serve as a considerable green method for treatment of antimicrobial MDR bacteria.
本研究报告了菊苣（俗称菊苣）天然提取物与冷大气压氩等离子体处理联合对抗多药耐药（MDR）革兰氏阴性细菌的显著抗菌活性。为了检测氩等离子体中产生的反应性物质，记录了光发射光谱。分子带被分配给羟基自由基（OH）和中性氮分子（N）。此外，确定了发射光谱的原子线分别为氩原子（Ar）和氧原子（O）。结果表明，菊苣提取物在 0.043 g/ml 的浓度下可使铜绿假单胞菌细胞的代谢活性降低 42%，而大肠杆菌生物膜的代谢活性降低 50.6%。此外，菊苣提取物与 3 分钟氩等离子体的组合产生了协同作用，因此对铜绿假单胞菌的代谢活性降低了 84.1%，对大肠杆菌的代谢活性降低了 86.7%。还通过 CLSM 分析了用菊苣提取物和氩等离子体射流处理的铜绿假单胞菌和大肠杆菌生物膜的细胞活力与膜完整性之间的关系。结果发现，在联合处理后，形成了明显的膜破坏。此外，研究还表明，在更长的等离子体暴露时间下，大肠杆菌生物膜对氩等离子体的敏感性高于铜绿假单胞菌生物膜。本研究表明，基于菊苣提取物和冷氩等离子体处理联合作用的抗生物膜治疗可以作为一种有前途的绿色方法，用于治疗抗菌 MDR 细菌。
