In Vitro Antioxidant Properties of Lactobacillus gasseri Isolated from Fermented Milk: Isolation and Preparation of Strains and Intracellular Cell-Free Extracts, Chemical Testing (Hydrogen Peroxide, Superoxide, Hydroxyl Radical, DPPH, Ferrous Ion Chelatin. Indones. j. sci. technol. 2024;9(3):611-622. doi:10.17509/ijost.v9i3.72186