CHARACTERIZATION OF BIOSURFACTANTS FROM OIL RESERVOIR ISOLATES AND THE POTENTIAL AS SURFACTANT SUBSTITUES IN COSMETIC FORMULATIONS

• Main Author: Aprilia S, Khoirunnisa
• Format: Final Project
• Language: Indonesia
• Subjects: Ilmu hayati ; Biologi
• Online Access: https://digilib.itb.ac.id/gdl/view/84413
• Institution: Institut Teknologi Bandung

The increasing of individual needs to improve their appearance has caused cosmetics to become part of society. However, many skin care product manufacturers use chemical surfactants as ingredients in their formulations, primarily as emulsifiers and foaming agents. Some of these products have been reported to alter skin flora, as well as cause allergic reactions and skin irritation. Biosurfactants are natural compounds that over several advantages over synthetic surfactants, such as derived from renewable resources, low toxicity, compatibility with human skin, their function as emulsifiers, reducing surface tension, and foaming which is important in cosmetic formulations. The anti-microbial, anti-adhesive, anti-fungal, and anti-viral activities of biosurfactants also make it very attractive for cosmetic and personal care applications. This research aims to determine biosurfactant-producing bacteria that potentially to replace chemical surfactants along with their antimicrobial capabilities. The research began by characterizing oil reservoir bacterial macroscopically, microscopically, and 16s rRNA sequencing. Then, their ability to produce biosurfactant was screened using oil spreading and emulsification tests. The selected biosurfactants were tested for their antimicrobial ability against representative skin enfection-causing microorganisms, such as S. aureus, P. aeruginosa, E. coli, C. albicans, and A. brasiliensis using microdilution, then one biosurfactant was chosen based on the highest growth inhibition percentages. Further tests include biosurfactant ionic charge, production curve, critical micelle concentration (CMC), and contact angle analysis. After that, the biosurfactant was characterized using FTIR and LC-MS analysis to determine its type and composition. Based on oil spreading screening using bacterial culture, 7 isolates show clear zone indicating biosurfactant production. Among these, 3 isolates which exhibit the highest emulsification, such as III2-1 (70,9%); I7K1 (63,92%); and III0-3 (63,29%) were selected to evaluate its antimicrobial activity. Based on the antimicrobial ability test, only I7K1 biosurfactant show growth inhibitory activity against S. aureus (17,75%) and A. brasiliensis (8,40%) at MIC 1000 ppm, P. aeruginosa (14,93%) at MIC 500 ppm, as well as E. coli (13,32%) and C. albicans (51,57%) at an MIC of 125 ppm. For the biosurfactant production and CMC curve, the highest dry weight biosurfactant was produced at the 18th hour of 0,1086 g/L and the CMC value was 0,1 g/L. The contact angle analysis indicates increased hydrophobicity of the substrate (glass slide) after treatment with I7K1 biosurfactant, evidenced by the contact angle >15,55o compared to the negative control without treatment. Therefore, isolate I7K1 shows potential in producing biosurfactants with antimicrobial properties against skin infection-causing species.