Determination of antimicrobial activity of some commercial fruit (apple, papaya, lemon and strawberry) against bacteria causing urinary tract infection

Abstract

Urinary Tract Infection (UTI) is a worldwide phenomenon in modern times, in which the dependency on antibiotics for its treatment is increasing. The current study was conducted in order to find alternatives to antibiotics by investigating some commercial fruits for their antimicrobial activity. The fruits in this study included green apple (Malus domestica), papaya (Carica papaya), lemon (Citrus limon), and strawberry (Fragaria ananassa), which were used to prepare methanolic and ethanolic extracts through Soxhlet extraction technique. The extracts were used against bacteria that cause UTI, and five different strains were selected: E. coli (ATCC: 15922), E. coli (ATCC: 25922), Pseudomonas aeruginosa (ATCC: 27853), Enterococcus faecalis (ATCC: 29212), and Klebsiella pneumoniae. Antimicrobial tests of the extracts were conducted by following the agar well diffusion method, where ciprofloxacin was used as a positive control, and autoclaved distilled water was used as a negative control. Among the fruits, apple and papaya extracts did not show any zone of inhibition against any of the tested bacteria. However, both lemon and strawberry extracts showed inhibition zone against all of the mentioned bacteria. The ethanolic extracts of lemon and strawberry were more potent than their methanolic extracts. Lemon ethanolic extract showed the highest zone of inhibition against Pseudomonas aeruginosa (ATCC: 27853) (18.34 ± 0.58) and lowest one against Klebsiella pneumoniae (16.00 ± 1.00). Strawberry ethanolic extracts showed the highest zone of inhibition against Pseudomonas aeruginosa (ATCC: 27853) (16.33 ± 0.58) and the lowest one against Klebsiella pneumoniae (13.33 ± 0.58). As antibiotic resistance is paving the way for multidrug resistant bacteria, the results of lemon and strawberry can be considered to be used as an antimicrobial agent in treating urinary tract infections. © 2018 The Author(s).