Mushrooms are a nutritionally functional food and a source of secondary metabolites
with physiologically activity [1]. A few studies have been reported on the antimicrobial
activity of edible mushroom Pleurotus and its bioactive compounds. Hexane extracts of four Pleurotus spp. strains (IE200, IE201, ECS127 and RP) were evaluated for antibacterial activity
by the single disk method [2]. Antibacterial activity was tested against the pathogenic
Gram-positive strains of Bacillus subtilis and Staphylococcus aureus or Gram-negative strains Enterobacter agglomerans, Shigella dysenteriae, Yersinia enterocolitica, Klebsiella rhinoescleromatis, and K. pneumoniae. The edible mushrooms strains were cultivated on straw substrate to obtain fruiting
bodies, the fine dried mushroom powder (20 mesh) sample (10g) was then extracted with
hexane and extracts concentrated to dryness in rotary evaporator under vacuum. All
bacteria were grown (1.5×108 CFU/mL, 0.5 McFarland) in nutrient broth incubated at 37°C for 24h and plated, onto
Petri dishes containing Müeller-Hinton agar. At the same time, sterile discs of 5mm
diameter were embedded with 20µL (4mg/mL) of hexane extracts of each strain – experimental
group – or with the solvent or chloramphenicol (30 mcg) – control groups – and added
to the cultured dishes. Toxicity of the mushrooms extracts against microorganisms
was determined after 24h by measuring the diameter of the halo around the discs, oneway
ANOVA was applied. All the strains revealed antimicrobial activity showing different
selectivity (Duncan, p<0.05), the IE200 and IE 201 white strains showed better
results than pink strains (ECS127 and RP).
Acknowledgements: Supported by SIP 20070922, IPN, 2007–2008.
References: 1. Wasser S.P., Weis, A.L. (1999) Int. J. Med. Mushrooms 1: 31–62.
2. Indu M.N. et al. (2006) Braz. J. Microbiol. 37: 153–158.
