Optimization of the Purification Process for <i>Lactiplantibacillus plantarum</i> Lipoteichoic Acid with Anti-Biofilm Properties against Dental Pathogens

Biofilms formed by oral pathogens play a critical role in the initiation and development of various dental diseases by enhancing resistance to dental medicaments. Previously, we reported the potent anti-biofilm activity of <i>Lactobacillus</i> lipoteichoic acid (LTA), a major cell wall component of Gram-positive bacteria, against various dental pathogens. Nevertheless, the practical application of LTA as an anti-biofilm agent is limited due to its complex, cost- and labor-intensive purification processes. Therefore, to minimize the purification processes required to obtain LTA with anti-biofilm activity, we isolated LTA from <i>Lactiplantibacillus plantarum</i> (Lp.LTA) and its intermediates following each purification step, and compared their anti-biofilm activity against dental pathogens. The Lp.LTA intermediates underwent sequential purification after butanol extraction and hydrophobic-interaction chromatography, and these were designated as LTA-Butanol and LTA-HIC, respectively. The results of Western blot analysis demonstrated that LTA-HIC has a higher concentration of LTA than LTA-Butanol. Although both LTA-Butanol and LTA-HIC dose-dependently inhibited <i>Streptococcus mutans</i> and <i>Porphyromonas gingivalis</i> biofilm formation, the anti-biofilm activity of LTA-HIC was superior to that of LTA-Butanol and comparable to Lp.LTA. Furthermore, sodium hydroxide treatment of LTA-HIC diminished its anti-biofilm activity, suggesting that LTA is a key component responsible for the anti-biofilm capacity of LTA-HIC. Collectively, these results demonstrated that LTA-HIC serves as an intermediate in the LTA purification, retaining its anti-biofilm properties and offering a viable solution to the challenges associated with the LTA purification process.