Study antibacterial effects of hydroalcoholic extract of acorn fruit ́s (Quercus branti) against Listeria monocytogenes and Enterococcus faecalis in vitro

Fundamental research on medicinal plants for the detection of medical effective agents and effect on biological pathogens, in medicinal plant research centers all over the world, particularly Iran is increasing in recent years. This study was aimed to determine the level of tannins in acorn fruit´s (Quercus branti) and antibacterial effects of hydroalcoholic extract against Listeria monocytogenes and Enterococcus faecalis, two human pathogenic bacteria was done.
In this fundamental- experimental study, after preparation of acorn fruit´s (Quercus branti) and drying and powder suitable conditions using ethanol, the extract was prepared by maceration and percolation methods. Tannin content was measured by colorimetric method and using of Folin-Deni's reagent. The antibacterial effects of this extract to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was performed by broth microdilution method.
Based on these results, tannin content per gram of dry extract were 123.5±3.5 mg and MIC and MBC of of Quercus branti extract for Listeria monocytogenes were respectively 2 and 8 mg/ml and for Enterococcus faecalis 2 and 4 mg/ml.
The results showed that the extract of acorn fruit´s (Quercus branti) by having high tannins has antimicrobial, bactericidal and inhibitory effect on the human pathogen L. monocytogenes and E. faecalis.