Date of Completion
2025
Document Type
Thesis
Degree Name
Bachelor of Science in Life and Health Sciences
Keywords
Armoracia rusticana, Allyl isothiocyanate, Antimicrobial activity, Kirby-Bauer assay, LC-MS, Staphylococcus aureus, P. aeruginosa, S. pneumoniae and E. coli.
Abstract
This study investigates the antimicrobial potential of Armoracia rusticana (horseradish) extract, with a focus on allyl isothiocyanate (AITC)-a bioactive compound derived from glucosinolate hydrolysis. Aqueous enzymatic extraction was employed, followed by phytochemical profiling via liquid chromatography-mass spectrometry (LC-MS), and antimicrobial testing against two Gram-positive (Staphylococcus aureus, Streptococcus pneumoniae) and two Gram-negative strains (Escherichia coli, Pseudomonas aeruginosa). Inhibition zones were measured using the Kirby-Bauer disc diffusion assay across four volumetric extract concentrations (25%, 50%, 75%, 100%). Results revealed dose-dependent inhibition in S. aureus, with 100% extract achieving a mean zone of 9.77 mm and a calculated ECso of 148.79 μg/mL, indicating moderate antimicrobial activity. P. aeruginosa demonstrated weak but statistically significant responsiveness at higher concentrations, while S pneumoniae and E. coli exhibited negligible inhibition, consistent with known resistance mechanisms. Statistical analysis via one-way ANOVA and Tukey's HSD confirmed significant intergroup variation (p < 0.05) in extract-treated groups, supporting the strain-specific efficacy of the extract. Although AITC was not directly detected in LC-MS due to volatility and polarity constraints, unresolved MS/MS peaks suggest the presence of additional bioactive metabolites. Methodological limitations, including the absence of controlled myrosinase hydrolysis and GC-MS quantification, underscore the need for extract standardization and mechanistic validation. Nevertheless, the study affirms the selective in vitro antimicrobial activity of horseradish-derived phytochemicals and identifies methodological avenues for optimizing efficacy and compound detection.
First Advisor
Iluminada A. Ronio
APA Citation
Awe, F.,
Ortillo, F.,
&
Panis, N.
(2025).
Antimicrobial evaluation of Sinigrin hydrolysis product (Allyl isothiocyante) from Armoracia rusticana against common pathogenic bacteria (Staphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, and Pseudomonas auruginosa.
Bachelor of Science in Life and Health Sciences.
Retrieved from https://greenprints.dlshsi.edu.ph/bslhs/8