A review on effect of quercetin and kaempferol on biofilm forming bacteria

Quercetin and Kaempferol, flavonoids isolated from the medicinal plant Psidium guajava Linn.(Guava) studied for their activity against common pathogenic biofilm forming bacteria. Guava leaves are traditionally used for various common illness and are rich in phytochemical content, including different antioxidants. Biofilm-forming bacteria present a major clinical challenge due to their protective Extracellular Polymeric Substance (EPS) matrix and the presence of antibiotic-tolerant dormant cells, which lead to chronic, resilient infections. Quercetin and Kaempferol offer a promising, non-antibiotic strategy by specifically targeting crucial stages of biofilm development. Kaempferol mainly functions by inhibiting the initial bacterial attachment and adhesion to surfaces by downregulating surface protein production (e.g.,Staphylococcus aureus). Quercetin reduce the overall production of EPS and altering its monosaccharide composition due to which weak biofilm structural integrity. Quercetin demonstrates molecular efficacy by suppressing the expression of key genes related to virulence, stress response, and quorum sensing (e.g.,Salmonella Typhimurium). This mechanismuse forblocking adhesion and disrupting matrix maturation and signalingsuggests that Psidium guajava leaves extracts rich in these flavonoids are highly favorable candidates for developing novel therapies to combat persistent, antibiotic-tolerant infections in healthcare and food safety.