Characterization of biosurfactant Rhamno NR22 produced by Pseudomonas Aeruginosa NR22 (Ps.NR.22) / Lutfi Eiman Hamzah

Pseudomonas aeruginosa (Ps.NR.22) is an opportunistic pathogen that have abilitytoproduce glycolipids. Rhamno NR22 is essentially class of glycolipid that consist of one or mostly two 3-hydroxy fatty acids with a different chain of lengths that haveaconnection with one or two rhamno molecules. Rhamno NR22 was successfullyproduced by using Phosphate-limited proteose peptone-glucose-ammoniumsalt (PPGAS) medium. The extraction of Rhamno NR22 was run by centrifuge at 10000rpm and 4°C for 15 minutes before it went through freeze dryer to powderizedtheRhamno NR22. Thermogravimetric analysis (TGA) and nuclear magnetic resonance(NMR) analysis are applicable as a tools to understand the characteristics of RhamnoNR22. TGA reveal the mass lose in a Rhamno NR22 sample as a functionof temperature and time. At 900°C, the Rhamno NR22 still remains at 5 mg in90minutes. It remarks the endurance of Rhamno NR22. ¹H-NMR spectrumwas recordeddue to the purity of Rhamno NR22. The obtained of multiplicity represent theassignment (-CH₃-) and (-CH-OH-) on rhamnose moiety while several assignment such as (-CH(O)-CH₂COO) and (-(CH₂)-CH(O)-CH₂COO-) on β-hydroxyfatty acids. The fuctional group, chemical bond and chemical structure study fromNMRproduced dirhamnolipid which classified as hydrophobic. Hence, the result indicatethe physical characterization of rhamno NR22.