In Vitro Evaluation of Antioxidant Activity and Antibacterial Effects and Measurement of Total Phenolic and Flavonoid Contents of Quercus brantii L. Fruit Extract

ABSTRACT

Plant-based extracts, as alternatives to chemical compounds, are commonly use in pharmaceutical and food industries. Antibacterial properties of extracts are mainly considered in medicine. Because of the high incidence of infectious diseases, it is helpful to identify more agents that are able to treat diseases. Antioxidant effects have been reported for different plant extracts. We aimed to investigate antioxidant activity, total phenolic and flavonoid contents, and antibacterial effect of Quercus brantii L. fruit extract. In this study, Q. brantii L. fruit was extracted by maceration using ethanol 70%. Total phenolic content was determined by Folin-Ciocalceu reagent and gallic acid equivalence, and antioxidant activity was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) compared to butylated hydroxytoluene (BHT). Antibacterial effects were investigated by broth microdilution and measurement of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Then the effects of different concentrations of extract on Staphylococcus aureus and Enterococcus faecalis growth were investigated in comparison with vancomycin and nitrofurantoin. Our findings demonstrate that antioxidant activity of hydroalcoholic extract of Q. brantii L. fruit was more than that of BHT. Total phenolic content was derived (3.010 mg GAE/g DW). Flavonol and flavonoid contents were 1.813 and 0.654 mg/g, respectively. The extract was found to exert significant inhibitory effects on both studied bacteria. S. aureus was more susceptible than E. faecalis to Q. brantii L. fruit extract. Q. brantii L. fruit extract can exert considerable antioxidant effects, contains high amounts of phenolic, flavonol, and flavonoid compounds, and inhibits bacterial growth.

KEYWORDS:

• Antibacterial
• antioxidant activity
• in vitro
• Quercus brantii L. fruit extract

Acknowledgment

We thank the Medical Plants Research Center of the Shahrekord University of Medical Sciences for cooperating with this study.

Declaration of interest

The authors declare no conflicts of interest. The authors alone are responsible for the content and writing of the article.

Additional information

Notes on contributors

Elahe Aleebrahim-Dehkordy

Elahe Aleebrahim-Dehkordy, Young Researchers and Elite Club, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran.

Mahmoud Rafieian-kopaei

Mahmoud Rafieian-kopaei, Medical Plants Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran.

Hossein Amini-Khoei

Hossein Amini-Khoei, Medical Plants Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran.

Safieh Abbasi

Safieh Abbasi, Department of Microbiology, Shahrekord University of Medical Sciences, Shahrekord, Iran.