Isolation and characterization of novel antibacterial compound from an untapped plant, Stereospermum fimbriatum

Abstract

Stereospermum fimbriatum or locally known as "Chicha" is traditionally used for itchy skin, earache, stomachache and postpartum treatments. This study was designed to evaluate the antimicrobial potential of S. fimbriatum's stem bark against 11 pathogens and isolate its bioactive compound. Successive soxhlet extraction was conducted using n-hexane, dichloromethane (DCM) and methanol. Disc diffusion, minimum inhibitory and bactericidal concentration (MIC & MBC) assays were done to examine the antimicrobial activity.Bioassay-guided isolation was conducted on S. fimbriatum's extract. The DCM extract of stem bark (DS) was the most potent extract followed by n-hexane extract of the stem bark (NS). A novel compound was isolated and coded as C1 which demonstrated potent antibacterial effects with the MIC values as low as 3.13 µg/mL to 6.25 µg/mL, against S. epidermidis, MRSA and S. aureus. Thus, S. fimbriatum could be a potential source of antimicrobial agents for the treatment of skin infections, specifically, MRSA.

Structure-dependent activity of plant natural products against methicillin-resistant Staphylococcus aureus

“…Phytochemical investigations of Stereospermum fimbriatum , a plant that is traditionally used for itchy skin, earache, stomachache, and postpartum treatment yielded the angucycline derivative 183 , which displayed a MIC value of 6.25 μg/mL ( Awang et al, 2020 ). Five anthraquinones ( 184–189 ) were studied in a in silico -based screening for new anti-microbial agents by Alhadrami et al (2022) .…”

Formulation and Biological Evaluation of Mesoporous Silica Nanoparticles Loaded with Combinations of Sortase A Inhibitors and Antimicrobial Peptides

“…The MICs of each SrtAI-loaded MCM-41 and MCM-41-PO 3 − formulation against four bacterial strains ( S. aureus (MSSA) ATCC25923, MRSA ATCC43300, E. coli ATCC25922, and P. aeruginosa ATCC27853) were determined using the CLSI BMD method [ 24 ] with a resazurin colorimetric readout [ 20 ]. For this method, quantities of SrtAI-loaded MCM-41 or MCM-41-PO 3 − containing 1 mg of individual SrtAIs were suspended in MHB (to 1 mL) to yield a 1 mg/mL final SrtAI concentration.…”

Exploring Anthraquinones as Antibacterial and Antifungal agents

“…Following a bioassay‐guided isolation, substituted tetraphene‐1,7,12(2 H ,4a H ,12b H )‐trione 22 (Figure 2)was obtained from the stem bark extract of S. fimbriatum . This trione derivative was found to be active against MRSA, S. aureus , and S. epidermidis with MIC ranging from 3.13–6.25 μg/mL [54] . Yang et al [55] .…”

“…This trione derivative was found to be active against MRSA, S. aureus, and S. epidermidis with MIC ranging from 3.13-6.25 μg/mL. [54] Yang et al [55] isolated three novel methoxy substituted anthraquinones along with four known anthraquinone derivatives from the twigs of Cassia auriculata. Several compounds including 3,6-dimethoxy-5-methylanthraquinone substituted with 2-hydroxyethyl group 23, substituted with 3-hydroxypropyl group at second position 24 and alataquinone A 25 exhibited potential activity against MRSA with MIC ranging from 4.2-5 μg/mL (Figure 2).…”