eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2025-09-30 22 3 1016 1027 10.13005/bbra/3420 56361 article Patrícia Maria Rocha 1 Carlos Eduardo de Araújo Padi 1 Everaldo Silvino dos Santos 1 Department of Chemical Engineering, Federal University of Rio Grande do Norte, Natal, Brazil Biosurfactants have potential applications in environmental sectors, as well as in the pharmaceutical, food, and other industries. Among the various classes of biosurfactants, lipopeptides, particularly surfactin and iturin, stand out. In the present study, the kinetic parameters related to the synthesis of surfactin and iturin were evaluated, along with the characterization of these biosurfactants produced by Bacillus subtilis UFPEDA 438. Additionally, extraction assays were conducted using a range of organic solvents (n-hexane, n-octanol, and chloroform-methanol 2:1, v/v), both with and without the addition of di-(2-ethylhexyl) phosphoric acid (D2EHPA). Maximum concentrations of surfactin and iturin were reached at 24 hours, corresponding to 187.01 ± 0.37 mg/L and 10.80 ± 1.03 mg/L, respectively. The lipopeptides exhibited good stability across a wide range of temperatures (20 to 100°C) and pH values from 6 to 9, and a critical micelle concentration (CMC) of 18.70 mg/L. The addition of the complexing agent D2EHPA, in combination with n-octanol (76.36%) and n-hexane (72.96%), improved the recovery efficiency of iturin. Regarding surfactin, n-octanol alone provided the highest recovery rate, reaching 72.22%. https://www.biotech-asia.org/vol22no3/lipopeptides-produced-by-bacillus-subtilis-ufpeda-438-using-sugarcane-molasses-as-a-carbon-and-energy-source/ Biosurfactants; D2EHPA; Iturin; Liquid-liquid extraction; Surfactin