Date of Completion

2024

Document Type

Thesis

Degree Name

Bachelor of Science in Pharmacy

Keywords

Antibiofilm, Antibacterial

Abstract

Antimicrobial resistance has been a long-standing problem that has continued to persist through time because of its unhindered progression globally. P. aeruginosa is a gram-negative obligate aerobe, a strain that is linked to causing hospital-acquired pneumonia (HAP) and is classified as an ESKAPE pathogen due to its varying barrier formation and virulence. The protective layer utilized by a bacterial strain for resistance is biofilm formation, also known as the mechanism of virulence (Cepas et al., 2019). In-vitro studies show that combinations of the plant extract and antimicrobial agents may enhance the effect of each other by acting as synergists. Plant compounds can modify the resistance of the bacteria, making it more sensitive to the antibiotic at low concentrations, which may reduce the required effective dose of the antibiotic (Stefanović, 2018). This study determines the antibiofilm activity of Laurus nobilis crude methanolic leaf extracts and its synergistic antibacterial activity with ceftriaxone against Pseudomonas aeruginosa ATCC 15442. The collected leaves were garbled, air dried, and then subjected to maceration and rotary evaporation to collect the crude extract. Twenty grams of the leaves yielded 2.333 g of the crude extract, with a percent yield of 11.68. The extractives were then subjected to MIC determination, of which 100 mg/mL was the lowest concentration that has a significant antibacterial activity. The L. nobilis crude methanolic leaf extracts were then subjected to biofilm inhibition and eradication determination, producing 30.08% biofilm inhibition and 15.56% biofilm eradication against P. aeruginosa ATCC 15442. Lastly, the extractive and ceftriaxone underwent fractional inhibitory concentration (FIC) determination and according to the FIC index, the combination was indifferent yielding no synergistic, additive, or antagonistic activity.

First Advisor

James S. Dayrit, RPh

Download

Share

COinS