Abstract
AIM: This study aimed to formulate a protocol to isolate and characterize immunoglobulin Y (IgY) antibodies from chicken egg yolk and evaluate its potential in inhibiting Streptococcus mutans. MATERIALS AND METHODS: Part A: IgY was extracted from fresh chicken egg yolk using a polyethylene glycol precipitation method. The isolated IgY was characterized using ultraviolet-visible (UV-Vis) spectroscopy to assess protein concentration and purity, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for molecular weight confirmation, high-performance liquid chromatography (HPLC) for purity, and mass spectrometry for further protein analysis. Functional activity was evaluated using Western blotting and enzyme-linked immunosorbent assay (ELISA) to confirm antigen binding. PART B: antimicrobial testing: (i) minimum inhibitory concentration (MIC) assays: determining the lowest concentration of IgY that inhibits the growth of each pathogen and (ii) zone of inhibition tests: measuring the effectiveness of IgY in inhibiting pathogen growth on agar plates. The concentration of IgY 50 μl, and 100 μl was utilized against S. mutans, Enterococcus faecalis, and Candida albicans. RESULTS: The UV-Vis spectroscopy results indicated a high concentration of IgY with minimal impurities. SDS-PAGE revealed a single band at approximately 180 kDa, corresponding to the expected molecular weight of IgY, with no significant contamination. HPLC analysis confirmed a pure IgY preparation with a single major peak. Mass spectrometry further validated the molecular weight of the IgY at ~180 kDa. Functional assays (western blotting and ELISA) demonstrated that the isolated IgY retained its ability to bind specifically to S. mutans, confirming its potential as an antimicrobial agent. MIC assays showed that IgY effectively inhibited the growth of endodontic pathogens at relatively low concentrations. The zone of inhibition for S. mutans group was as follows: positive control (PC) - 13 mm, test-50 μL - 11 mm, and test 100 μL - 20 mm; for E. faecalis - 50 μL - 14 mm, 50 μL - 15 mm, and PC - 15 mm; for C. albicans - 100 μL - 26 mm 100 μL - 24 mm and PC - 18 mm. CONCLUSION: IgY antibodies isolated from chicken egg yolk were characterized as highly pure and functional, with a strong potential for use in inhibiting S. mutans - an established dental caries causative microorganism. The use of IgY could offer an effective, ethical, and cost-efficient alternative to mammalian antibodies in oral health treatments, particularly for targeting S. mutans, and can be a viable therapeutic tool in passive immunization, caries prevention, and caries inhibition. It also has inhibitory potential on E. faecalis and C. albicans and can be developed as a therapeutic agent in endodontic infections.