Aktivitas Antibakteri Protein Serisin Bombyx mori dan Samia cynthia ricini terhadap Escherichia coli dan Staphylococcus aureus

Abstract

This study was designed to investigate the antibacterial properties of the sericin protein Bombyx mori and Samia cynthia ricini against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus strains. Sericin protein was extracted from the cocoons of B. mori races A, B, C, D, F1-1, F1,2 and S. ricini from Indonesia using a degumming process. Afterwards, the extract sericin protein were evaluated as antimicrobial such as Kirby Breuer disc diffusion, spectrometer measurement in decreasing OD value, and imaging Scanning Electron Microscope (SEM). The tests revealed that sericin protein from B. mori was more capable of inhibiting bacteria S. aureus than E. coli, whereas sericin protein from S. ricini was capable of strongly inhibiting both S. aureus and E. coli bacteria. The sericin proteins of B. mori and S. ricini were found to reduce the number of S. aureus and E. coli bacteria as the OD value decreased at a concentration of 9%. According to SEM imaging, sericin B. mori and S. ricini proteins caused changes in cell morphology in S. aureus and E. coli bacteria, resulting in bacterial cell function disruption and death. Sericin protein B. mori and S. ricini were able to against bacteria S. aureus than E. coli. Therefore, sericin protein is a potential to be antibacterial, particularly against Gram-positive strain S. aureus.