The Antibacterial Activity of Coriolus versicolor Methanol Extract and Its Effect on Ultrastructural Changes of Staphylococcus aureus and Salmonella Enteritidis

Abstract

The antibacterial activity of methanol extract obtained from fruiting body of industrially grown basidiomycete Coriolus versicolor was examined. The Minimum Inhibitory Concentration (MIC) values against various bacteria ranged from 0.625 to 20 mg mL-1. C. versicolor expressed bactericidal activity against both Gram-positive and Gram-negative bacteria. The growth curves of Staphylococcus aureus and Salmonella enterica serovar Enteritidis, measured at 630 nm, and confirmed with macrodilution method showed that the obtained extract could inhibit the growth of tested bacteria. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the loss of 260-nm-absorbing material were used to examine the ultrastructural changes in bacteria induced by the extract. When S. aureus was exposed to the MIC of C. versicolor, elongated and malformed cells were observed by SEM, while S. Enteritidis treated cells appeared shorter and aggregated with ruptured cell walls. TEM revealed the formation of non-membrane-enclosed bodies and depleted inner content of S. aureus. Larger and irregular periplasmic space and deformed and scattered components of the cell envelope were observed in treated S. Enteritidis. The loss of 260-nm-absorbing material indicated that the disruptive action of the extract on cytoplasmic membrane was more pronounced in S. aureus than in S. Enteritidis treated cells. The UV and FTIR spectrophotometric analyses revealed diverse composition of C. versicolor extract and high content of total phenolics. Altogether, mushroom extracts could be used to develop nutraceuticals or drugs effective against pathogenic microorganisms.

Selenium‐enriched Coriolus versicolor mushroom biomass: potential novel food supplement with improved selenium bioavailability

“…Total phenolic content was determined using Folin–Ciocalteu reagent (Merck KGaA, Darmstadt, Germany) and gallic acid (Merck, Schuchardt OHG, Hohenbrunn, Germany) as a standard …”

“…Commercial C. versicolor preparations (polysaccharopeptide krestin, PSK, and polysaccharopeptide, PSP) acquired by extraction of mycelium can be found on the market. Many studies have shown the antimicrobial, antitumoral and antioxidative effects of various C. versicolor extracts …”

The antibacterial activity and modes of LI-F type antimicrobial peptides againstBacillus cereus in vitro

“…The structure of B. cereus was observed via scanning electron microscopy (SEM) and transmission electron microscopy (TEM) according to a previously described method (Matijašević et al . ) with slight modifications. Briefly, bacterial cells in the log phase were collected, centrifuged (5000 g for 5 min at 4°C), washed three times and resuspended in PBS containing 16 μ g ml −1 AMP‐jsa9.…”

Chemical composition and biological activities of methanol extract from Macrocybe lobayensis

“…However, organic compounds specifically phenolic constituents are mainly recognized as active therapeutics and they could easily be obtained through methanol extraction process (Matijašević et al, 2016). Likewise, methanol was used in the present study for preliminary investigation on bio-organic components of M. lobayensis entailing medicinal effects.…”

“…For phenolic compounds, it was evidenced that the number and site(s) of hydroxyl groups determines their toxic effect to microorganisms which is possibly executed by enzyme inhibition. Further, the other secondary metabolites, for instance flavonoids, are proposed to act against microbial infections by inhibiting cell membrane, cell wall and nucleic acid synthesis along with energy metabolism (Matijašević et al, 2016). On the other hand, the mode of action of alcohols and terpenes involves disruption of microbial membranes.…”