Solubility of the extract

The solubility of the triterpenic extract was determined by adding the extract (in excess) to 1 mL of soybean, sunflower, and olive oil. The samples were heated at 40 °C for 15 min. Then, they were kept under constant magnetic stirring for 48 h at 25 ± 1 °C. The samples were centrifuged (Hettich MIKRO 220R, Hettich, DEU) at 18840g for 30 min (15 °C) to remove excess undissolved extract and the supernatant was recovered (Fasolo et al., 2020). The supernatant was filtered (0.45 µm) and adequately diluted with methanol for the determination of the extract content at 210 nm using a spectrophotometer (Cary 50 Bio UV–Visible, Varian, Mulgrave, AUS). The content of triterpenic extract was expressed as equivalents of lupeol, one of the major components of the extract (Ramos-Hernández et al., 2018). A calibration curve of lupeol (dissolved in methanol) ranging from 0 to 1000 ug/mL was performed and calculation was done using the straight line equation, y = 0.9699x – 0.0036; R² = 0.9978.