Publication: Antibiofilm activity of quercus infectoria (QI) gall methanol extract against biofilm-forming staphylococcus aureus
| dc.contributor.author | Rajendra, Abiramy | |
| dc.date.accessioned | 2026-08-20T06:26:19Z | |
| dc.date.available | 2026-08-20T06:26:19Z | |
| dc.date.issued | 2026-01 | |
| dc.description.abstract | Quercus infectoria (QI) galls, rich in hydrolysable tannins and phenolic compounds, have long been used in traditional medicine and are increasingly studied as sources of novel antimicrobial and antibiofilm agents. This study evaluated the antibiofilm activity of QI gall methanol extract against Staphylococcus aureus ATCC 29213, focusing on (i) biofilm kinetics, (ii) minimum inhibitory (MIC) and bactericidal concentrations (MBC), and (iii) biofilm-inhibitory and biofilm-eradication effects at defined developmental stages. QI galls were extracted using absolute methanol, and the crude extract was concentrated and stored at 4 °C. MIC and MBC against planktonic S. aureus were determined by broth microdilution and confirmed via subculture. Biofilm formation was modelled in microtiter plates, with incubation for initial adherence (3 hours) and maturation (14 hours). Extract effects at 1x and 2x MIC were assessed using resazurin reduction combined with corrected optical density (OD570 – OD600). In the adherence phase, extract concentration and exposure time did not significantly inhibit early attachment, suggesting tolerance of initial adhesion to tested concentrations. In contrast, during biofilm maturation, corrected OD decreased markedly by 24 hours, indicating substantial inhibition or disruption of metabolically active biofilm, followed by partial regrowth at 48 hours. These results suggest that QI gall methanol extract is more effective against established biofilms than early adhesion events. This study provides quantitative, phase-specific evidence supporting the antibiofilm potential of QI gall extract. Despite limitations including a single strain, two concentrations, and reliance on a single assay, the findings justify further evaluation using multiple strains, complementary structural and viability assays, extended dosing, and combination therapy to explore potential synergy against S. aureus biofilms. | |
| dc.identifier.uri | https://erepo.usm.my/handle/123456789/24871 | |
| dc.language.iso | en | |
| dc.title | Antibiofilm activity of quercus infectoria (QI) gall methanol extract against biofilm-forming staphylococcus aureus | |
| dc.type | Resource Types::text::thesis::bachelor thesis | |
| dspace.entity.type | Publication | |
| oairecerif.author.affiliation | Universiti Sains Malaysia |