Supercritical extraction from L. rivularis stalks using ethanol-modified supercritical CO2 was studied. The effects of ethanol concentration (0.5-1.5 wt.%) and pressure (20-40 MPa) on the total extract yield (Y-1, g/kg d.s.), phenolics extraction yield (Y-2, mg GAE/kg d.s.), antioxidant (Y-3, mmol TE/kg d.s.) and anti-inflammatory activities (Y-4=IC50, mg/mL) were studied. The greatest total extract yield, phenolics extraction yield and antioxidant activity were reached at 1 wt.% and 40 MPa. Anti-inflammatory activity improved with the addition of ethanol, being higher at 1.5 wt.%. The following results were obtained at the selected condition (1 wt.%, 40 MPa): Y-1 = 34.15 g/kg d.s, Y-2 = 658.44 mg GAE/kg d.s., Y-3 = 0.103 mmol TE/kg d.s. and Y-4 = 3.38 mg/mL. Important bioactive compounds like caryophyllene oxide, quercetin, kaempferol and resveratrol were quantified in the selected extract. The extract showed inhibitory capacity against alpha-amylase and alpha-glucosidase, demonstrating important bioactive properties.