Assessing therapeutic efficacy of <i>Chlorella vulgaris</i> peptides on pathogenic bacteria associated with periodontal disease

Periodontal diseases (PD) adversely impact periodontium caused by infectious bacteria. Recently, Chlorella species have been recognized for their preventive potential against various diseases. Therefore, we aimed to elucidate pharmacological activity of <i>Chlorella vulgaris</i> peptides (CVP, molecular weights of &lt;1 kDa, 1–3 kDa, 3–10 kDa, 10–30 kDa and &gt;30 kDa) for bacterial-associated periodontal disorders. We investigated anti-bacterial, anti-inflammatory profile, cell protection, and anti-osteoclastogenic profiles on <i>Streptococcus mutans, Streptococcus sanguis, Porphyromonas gingivalis</i>. The CVP 3–10 kDa and 10–30 kDa inhibited bacterial growth, elevated SCC-4 and RAW264.7 cell survival rate under LPS-treatment and reduced osteoclast numbers. <i>In vivo</i> study revealed significantly reduced oral bacterial count and MCP-1 in CVP 3–10 kDa gel-treated LPS+bacteria-induced mice, possibly by regulating TLR4 signaling and inhibiting inflammatory cytokines such as IL-6 and TNF-α. Conclusively, CVPs exert anti-bacterial, anti-inflammatory, cell protective, wound healing, and anti-osteoclastogenic activities and therefore could be a potential therapy for PDs.