ANTIBACTERIAL POTENTIAL OF RHAMNOLIPID-COBALT NANOPARTICLES WITH ECTOIN AS COSOLVENT

• Main Author: Arifi Ma'ruf, Nardyawan
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/82775
• Institution: Institut Teknologi Bandung

Antibacterials play an important role in public health, especially in preventing and treating infections. However, the excessive use of alcohol-based antibacterials during the COVID-19 pandemic raises concerns about the phenomenon of antimicrobial resistance (AMR). This phenomenon makes bacterial infections difficult to treat and leads to increased mortality rates. Therefore, efforts to diversify antibacterial agents are crucial. One biosurfactant, rhamnolipid, has potential as an alternative antibacterial that has broad spectrum activity against various microbes, including some resistant strains. Recent research shows that the effectiveness of rhamnolipids can be increased by converting them in the form of metal nanoparticles. In this research, cobalt (Co) metal is one of the potential metals for forming nanoparticles. As a surfactant, rhamnolipid has the potential to irritate the skin and eyes. To overcome this, the addition of ectoine, a cytoprotective compound produced by several extremophile microorganisms, is a promising solution. Rhamnolipid-Co nanoparticles with ectoine cosolvent are a promising antibacterial alternative because they are effective and environmentally friendly. Thus, in this research, nanoparticles were synthesized using the coprecipitation method and then characterized using FTIR, TEM, and PSA to confirm the formation of nanoparticles. The obtained nanoparticles were then tested for antibacterial activity by determining the minimum inhibitory concentration (MIC) for Staphylococcus aureus (S. aureus) bacteria. To ensure that the addition of ectoine does not affect the antibacterial activity, the fractional inhibitory concentration (FIC) was determined. Apart from that, testing of ectoine's ability to reduce the level of irritation was also carried out using the zein gravimetric method. The research results showed that rhamnolipid-Co nanoparticles were successfully synthesized with particle sizes reaching 200 nm based on TEM analysis. Antibacterial tests showed that rhamnolipid-Co nanoparticles were able to inhibit the growth of S. aureus bacteria better than free rhamnolipid in the concentration range of 1250 – 5000 ppm. Regarding the addition of ectoine cosolvent, data shows a reduction in the irritation level of rhamnolipid-Co nanoparticles by up to 23% without affecting their antibacterial activity.