A culture of L. acidophilus 04 grown in 100 mL MRS broth for 24 h at 30°C was centrifuged at 10,000 g for 10 min. The supernatant was sterilized by passage through a 0.25 µM syringe driven filter (Himedia, India), and neutralized (pH 7.0) with 2 N NaOH