Unraveling the Intricate Roles of Plant Secondary Metabolites in Mitigating Bacterial Multidrug Resistance: Challenges and Prospects

Secondary metabolites are natural compounds produced by medicinal plants and have long served a crucial role in the prevention and treatment of microbial infections, showcasing their potential over conventional antimicrobial therapies. They have emerged as vital components in agronomy, pharmacy, and international markets due to their growing demand as raw materials for pharmaceutical applications and their increasing utility in daily life. These natural products offer a promising alternative to traditional antibiotics, particularly in combating antibiotic resistance and controlling bacterial infections through novel mechanisms. Secondary metabolites of medicinal plants can disrupt the various resistance mechanisms in bacteria, like the quorum sensing system of bacteria, and also interfere with the cellular mechanism of bacteria, e.g., inhibition of signal molecule production, degradation of signal molecules, blocking signal receptors, disruption of signal transduction, modulation of gene expression, inhibition of synthesis of DNA and proteins, blocking of oxidative respiration, etc. This present Review elucidates the in vitro antibacterial efficacy and mechanisms of various secondary metabolites, such as alkaloids, flavonoids, tannins, and terpenoids, extracted from medicinal plants. Also, the study highlights the importance of bioactive compounds for managing drug resistance in highly pathogenic bacterial infections and other pharmaceutical applications.