<b>Background and Objective:</b> The emergence of methicillin-resistant community-acquired <i>Staphylococcus aureus </i>and antibiotic-resistant <i>Neisseria gonorrhoeae</i> has raised significant concerns. Efforts to combat resistance involve the exploration of novel alternative therapies, particularly those derived from insect components. <i>Rhynchophorus</i> sp., a coconut pest commonly found in Southeast Asia, has haemolymph that exhibits bactericidal properties<i>.</i> The objective of this study was to assess the potential of the haemolymph of <i>Rhynchophorus</i> sp., larvae as an antimicrobial agent against Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) and <i>Neisseria gonorrhoeae</i>. <b>Materials and Methods:</b> In this study, <i>Rhynchophorus</i> sp., larvae were gathered for the purpose of haemolymph extraction. These larvae were then divided into distinct groups, with one group subjected to immunization using <i>Escherichia coli</i>, while another group was left unimmunized. The study utilized the well diffusion method to evaluate antibacterial effectiveness. <b>Results:</b> Haemolymph fluid extracts from <i>Escherichia</i> coli-immunized <i>Rhynchophorus</i> sp., larvae, exhibited strong antibacterial activity, with an average value of 19.3±0.47 mm, against MRSA, more enhanced compared to unimmunized larvae. In contrast, haemolymph fluid extracts from <i>Escherichia coli</i>-immunized <i>Rhynchophorus</i> sp., larvae demonstrated a more moderate antibacterial activity, with a mean of 14.17±0.27 mm, against <i>Neisseria gonorrhoeae</i>, a level similar to unimmunized larvae. <b>Conclusion:</b> The haemolymph extracted from <i>Rhynchophorus </i>sp., beetles larvae exhibited antimicrobial effects against MRSA and <i>Neisseria gonorrhoeae</i>, particularly when it is enhanced through <i>Escherichia coli</i> immunization.
Keywords: Neisseria gonorrhoeae; Rhynchophorus sp.; antimicrobial; haemolymph; methicillin-resistant Staphylococcus aureus.