β-Sitosterol derived compound from onion husks non-polar fraction reduces quorum sensing controlled virulence and biofilm production

Abstract

Quorum sensing is an important regulatory factor of P. aeruginosa virulence induction such as BF, motility, formations of proteases, pyocyanin, and some toxins. The aim of the current study is to detect the effect of the pet.ether extract from onion husk and compound drive from it on quorum sensing and virulence formations of P. aeruginosa. Quorum sensing inhibiting effect of the pet.ether extract of onion husk and a compound drive from it, was evaluated by C. violaceum reporter using dilution method as well as an antioxidant by using DPPH. The efficacious of: Quorum sensing inhibiting on pet.ether fraction and compound derived from it, were investigated for their activities toward biofilm and pyocyanin synthesis as well as motility from P. aeruginosa. The pet.ether fraction and compound derived from it of onion husk exhibited potent antimicrobial, antioxidant and Quorum sensing inhibiting effects. The pet.ether fraction and compound derived from it possesses significant reduction on pyocyanin and biofilm induction of P. aeruginosa. Moreover, they significantly inhibited swimming motilities of P. aeruginosa. For the first time, our study showed the medical importance of Allium cepa L. as antimicrobial, antioxidant as well as Quorum sensing inhibiting and virulence suppressors of P. aeruginosa. Thus, these might emphasized on Allium cepa L as a natural source for attenuating toxins of the Pseudomonas.

Bioactive constituents with antibacterial, resistance modulation, anti-biofilm formation and efflux pump inhibition properties from Aidia genipiflora stem bark

“…Cinnamic acid derivatives of natural origin exhibited significant quorum sensing and biofilm inhibition in Chromobacerim violaceum increasing its susceptibility to tobramycin [42]. Pentacyclic triterpenes and some sterols including βsitosterol (3b) also demonstrated remarkable anti-biofilm activities [43,44]. Extract and plant derived compounds may inhibit biofilm formation by damaging microbial membrane structures, inhibiting peptidoglycan synthesis [45], inhibition of nucleic acid synthesis [46], quorum sensing inhibition or disruption [47] and anti-cell-adhesion properties [48].…”

Antibacterial, Antibiofilm, and Efflux Pump Inhibitory Properties of the Crude Extract and Fractions from Acacia macrostachya Stem Bark

“…Flavonoids in particular are among the compounds that exert antibiofilm effects through the inhibition of quorum sensing [ 39 ]. Pentacyclic triterpenes and some plant sterols including stigmasterol and β -sitosterol have demonstrated remarkable antibiofilm activities in pathogenic bacteria [ 18 , 40 ].…”

In vitro Antibacterial Activities, DPPH Radical Scavenging, and Molecular Modeling of Isolated Compounds from the Bark of Grewia ferruginea

“…The pulverized stem bark of G. ferruginea (800 g) was extracted with dichloromethane:methanol (1:1, 4 L) using maceration for 72 hours. After ltration, the extracts were concentrated under reduced pressure using a rotary evaporator at 40 to afford 112 g (14%) yield. About 100 g of the crude extract was dissolved in water and subsequently subjected to liquid liquid extraction using CHCl 3 , EtOAc, and n-butanol.…”

“…Along with compound 37, compound 38 was identi ed as a minor with relative amount of ca. 30% (calculated from peak area of respective proton, Figure S21) and proposed as 6-keto-5,6-dihydro-β-sitosterol by comparing with NMR spectral data of 7-keto-5,6-dihydro-β-sitosterol [40], β-sitosterol [30], 7-keto-β -sitosterol [39], and 6ketocholestanol [41]. The COSY (Figure S26) and HMBC (Figure S25) were used to con rm the structures of compounds.…”