Abstract

Microbial infections in the medical sector often lead to life-threatening systemic disorders due to their resistance to various classical antibiotic families. This work utilized a combination of jojoba oilcake and crude soybean oil for the first time as a low-cost substrate. In addition, a locally isolated and molecularly characterized yeast strain (Meyerozyma guilliermondii) was used for the economic production of sophorolipids (SLs). SLs were produced and extracted by methanol, giving a yield of 23.12/100g substrate. They reduced the surface tension (ST) to 39 mN/m (millinewtons/meter) with a critical micelle concentration (CMC) value of 240 mg/l. The produced SLs’ characterization investigations using Fourier transform infrared spectroscopy, Proton nuclear magnetic resonance, and Liquid chromatography-tandem mass spectrometry demonstrated the existence of both the acidic and lactonic forms of SLs. Interestingly, the activity of SLs against clinically drug-resistant pathogens was found to be highly suppressive for their growth. The produced SLs demonstrated a strong inhibitory effect against certain drug-resistant pathogens, primarily through mechanisms such as biofilm suppression, increased ROS generation, and membrane destabilization, all with minimal cytotoxicity. This approach could enhance their potential in combating drug-resistant infections.

Key words: Agro-industrial Wastes; Antibiofilm; Biosurfactants; Drug-resistant pathogens; Meyerozyma guilliermondii.