Since 2021, I have been assisting a post-graduate student in researching the effectiveness and utilization of antimicrobial peptides derived from Bacillus velezensis. Ensuring the practical application of this research, I have taken on the critical role of conducting safety tests, including acute and sub-chronic toxicity tests on mice. This chronicle experiment, spanning 30 days with twice-daily oral gavage, has not only honed my research skills but also reinforced my determination and perseverance.