Patel Ritu Raj, Mishra Aradhana, Singh Sudhir Kumar, Nath Gopal, Singh Meenakshi
Department of Medicinal Chemistry, Faculty of Ayurveda, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, India.
Virus Research and Diagnostic Laboratory, Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, India.
Microb Pathog. 2025 Nov;208:107985. doi: 10.1016/j.micpath.2025.107985. Epub 2025 Aug 12.
Biofilm formation in Mycobacterium species significantly contributes to their pathogenicity and resistance to conventional antimicrobial therapies, posing a major challenge in clinical management. Plant-derived phytoconstituents have emerged as promising alternatives due to their diverse biological activities, including anti-biofilm properties. Clerodendrum serratum, a medicinal plant known for antimicrobial potential, offers a rich source of such bioactive compounds. This study aimed to first optimize robust biofilm formation in three Mycobacterium species (M. smegmatis, M. fortuitum, and M. marinum) using specific nutritional supplements, followed by the evaluation of the anti-biofilm efficacy of C. serratum leaf extract against pre-formed mature biofilms. Finally, potential molecular targets and mechanisms of action of key phytoconstituents were investigated through in silico analysis. Enhanced biofilm formation was achieved by supplementing Middlebrook 7H9 broth with KHPO, (NH)SO, Acicase, and DTT, with KHPO showing the most pronounced effect. Disruption of pre-formed biofilms by C. serratum leaf extract was quantified using the crystal violet microtiter plate assay and confirmed via Atomic Force Microscopy (AFM), which revealed significant alterations in biofilm architecture. In silico molecular docking of five major phytoconstituents (Hispidulin, Luteolin, Salvigenin, Pectolinarigenin, and Uncinatone) with critical biofilm-associated targets (FadD32, InhA, and MmpL3) showed strong binding affinities of docking score up to -11.0 kcal/mol, indicating potential mechanisms of biofilm disruption. This study presents the optimization of enhanced biofilm formation in Mycobacterium species and demonstrates the anti-biofilm potential of C. serratum leaf extract. The integrated experimental and computational approach offers new insights into targeting resilient mycobacterial biofilms using plant-based therapeutics.
分枝杆菌属中的生物膜形成显著增强了它们的致病性以及对传统抗菌疗法的抗性，这给临床治疗带来了重大挑战。植物源植物成分因其多样的生物活性，包括抗生物膜特性，已成为有前景的替代方案。臭牡丹是一种以抗菌潜力闻名的药用植物，富含此类生物活性化合物。本研究旨在首先使用特定营养补充剂优化三种分枝杆菌（耻垢分枝杆菌、偶然分枝杆菌和海分枝杆菌）中强大的生物膜形成，随后评估臭牡丹叶提取物对预先形成的成熟生物膜的抗生物膜功效。最后，通过计算机分析研究关键植物成分的潜在分子靶点和作用机制。通过在Middlebrook 7H9肉汤中补充KHPO、(NH)SO、Acicase和DTT实现了生物膜形成的增强，其中KHPO的效果最为显著。使用结晶紫微量滴定板法对臭牡丹叶提取物破坏预先形成的生物膜进行了定量，并通过原子力显微镜（AFM）进行了确认，AFM显示生物膜结构有显著改变。五种主要植物成分（圣草酚、木犀草素、柳穿鱼素、果胶寄生素和钩状酮）与关键生物膜相关靶点（FadD32、InhA和MmpL3）的计算机分子对接显示对接分数高达-11.0 kcal/mol的强结合亲和力，表明了生物膜破坏的潜在机制。本研究介绍了分枝杆菌属中增强生物膜形成的优化，并证明了臭牡丹叶提取物的抗生物膜潜力。这种综合实验和计算的方法为使用植物疗法靶向抗性分枝杆菌生物膜提供了新的见解。
