Impact of Flavonoids and Nano Flavonoids Extraction from Bacopa monnieri on fimA Gene Expression in Serratia marcescens

Abstract

Serratia marcescens is multidrug‐resistant human pathogen bacteria. The pathogenicity of S. marcescens mainly depends on biofilms and quorum sensing gene are major virulence factors to resist antibiotics. Hence, targeting genes in S. marcescens will pave the way to combat its pathogenicity. This study aimed to assess the effect of Flavonoids and Nano Flavonoids on expression of fimA gene in S. marcescens . Flavonoid extraction from the Bacopa monnieri L. belong to family Plantaginaceae  and identification by using High Performance Liquid Chromatographic (HPLC), then casein was used to synthesis flavonoid-casein nanoparticles by using the ultrasound probe method. The chemical and physical properties of the nanoparticles were characterized using Fourier Transfor Infrared Spectroscopy (FT-IR) and Transmission Electron (TEM) techniques. S. marcescens were selected for this study due to their resistance to multiple antibiotics. The bacteria were first identified using the VITEK 2 system. The polymerase chain reaction (PCR) was performed to amplify the fimA gene. RT-PCR was carried out to determine the effect of flavonoids and nano-flavonoids on the fimA gene. Flavonoids and nano-flavonoids exhibited significant inhibitory effects on the expression fimA gene (the fold of gene expression: 0.00936 and 0.00052) respectively. The fimA gene, which encodes a major component of type I fimbriae involved in bacterial adhesion and virulence, was downregulated following treatment with both flavonoid and nano-flavonoid. The nano-flavonoids demonstrated a more potent effect due to enhanced cellular uptake and bioavailability. This results suggest the potential of flavonoids, especially in nano-form, as anti-virulence agents targeting fimA gene expression in S. marcescens.