Title

The Effect Of Phenolic Compounds (Benzoic Acid And Gallic Acid) On The Susceptibility Of S. Aureus To Trimethoprim-Sulfamethoxazole.

Author(s)

Aman Pitalia

School Name

Spring Valley High School

Grade Level

10th Grade

Presentation Topic

Microbiology

Presentation Type

Mentored

Mentor

Mentor: Dr. Xiaoming Yang; University of South Carolina School of Medicine: Pathology, Microbiology, & Immunology

Written Paper Award

2nd Place

Abstract

Benzoic Acid and gallic acid are common phenolic phytochemicals found in the natural environment. Both phenols have been found to increase the susceptibility of resistant microbes, making it more feasible to kill the microbe by antibiotics. The experiment modeled the effects of phenolic acids by placing them into an agar medium and exposing them to S. aureus. The antibiotic [Bactrim] disc was placed on the top and then the inhibition zone was measured after 24 hours to determine the antimicrobial effects of the phenols. It was predicted that higher concentrations of phenols would increase the susceptibility of the microbe, allowing the Bactrim to kill the S. aureus. The group consisting solely of the antibiotic and S. aureus served as a control for the experiment. The experimental group concentrations increased at similar levels for each phenol; gallic acid included further concentrations of 1200 µg/ml and 1600 µg/ml. The hypothesis that higher concentrations of each phenol would increase the susceptibility of the microbe, allowing the antibiotic to kill it, was supported by the benzoic acid; however, it was not supported by the gallic acid. At α=0.05, the benzoic acid significantly increased the susceptibility of the microbe, with a p < 0.001, f-crit = 3.4780497. The gallic acid proposed a larger zone size at lower concentrations, than significantly decreasing in zone size at higher concentrations with a p < 0.001, and f-crit = 2.847726. Benzoic acid seemed to have greater antimicrobial effects than gallic acid; however, smaller doses of gallic acid could still be effective against resistant strains.

Location

Owens 110

Start Date

4-16-2016 8:30 AM

COinS
 
Apr 16th, 8:30 AM

The Effect Of Phenolic Compounds (Benzoic Acid And Gallic Acid) On The Susceptibility Of S. Aureus To Trimethoprim-Sulfamethoxazole.

Owens 110

Benzoic Acid and gallic acid are common phenolic phytochemicals found in the natural environment. Both phenols have been found to increase the susceptibility of resistant microbes, making it more feasible to kill the microbe by antibiotics. The experiment modeled the effects of phenolic acids by placing them into an agar medium and exposing them to S. aureus. The antibiotic [Bactrim] disc was placed on the top and then the inhibition zone was measured after 24 hours to determine the antimicrobial effects of the phenols. It was predicted that higher concentrations of phenols would increase the susceptibility of the microbe, allowing the Bactrim to kill the S. aureus. The group consisting solely of the antibiotic and S. aureus served as a control for the experiment. The experimental group concentrations increased at similar levels for each phenol; gallic acid included further concentrations of 1200 µg/ml and 1600 µg/ml. The hypothesis that higher concentrations of each phenol would increase the susceptibility of the microbe, allowing the antibiotic to kill it, was supported by the benzoic acid; however, it was not supported by the gallic acid. At α=0.05, the benzoic acid significantly increased the susceptibility of the microbe, with a p < 0.001, f-crit = 3.4780497. The gallic acid proposed a larger zone size at lower concentrations, than significantly decreasing in zone size at higher concentrations with a p < 0.001, and f-crit = 2.847726. Benzoic acid seemed to have greater antimicrobial effects than gallic acid; however, smaller doses of gallic acid could still be effective against resistant strains.