Taro leaves extract and probiotic lactic acid bacteria: A synergistic approach to improve antioxidant capacity and bioaccessibility in fermented milk beverages

Abstract

Taro leaves extract (TLE) was used to manufacture two fermented milk beverages in concentrations of 250 and 500 mg/L (FMTLE 250 and FMTLE 500). The polyphenolic profile via HPLC, volatile compounds via GC-MS, antioxidant, antimicrobial activities of TLE, physicochemical properties, probiotic survival, and bioaccessibility of the supplemented beverages were also evaluated. TLE presented phenolic and flavonoid levels of 130.56 ± 1.55 μg GAE/g and 53 ± 1.15 CE μg/g, respectively. Sulfated polysaccharides, triterpenoids, and tannins were recorded (26.5 ± 0.8 μg/g, 7.30 ± 0.37 μg/g, 0.26 ± 0.03 μg/g). IC50 of the TLE measured using DPPH. assay was 144.83 ± 2.19 μg/mL, while the ABTS*+ assay was 100.48 ± 1.45 for determination antioxidant activity. The highest antimicrobial activity of TLE was observed against Salmonella enterica and Listeria monocytogenes with an inhibition zone of 15.5 and 13.6 mm, respectively. The survival of Lactobacillus paracasei showed no statistical difference between the control and FMTLE 250 and FMTLE 500 (P > 0.05). Antioxidant potential increased, with probiotics were stable through the digestion processes of the supplemented beverages and the increasing polyphenol concentration in the beverages. Sensory evaluation showed the acceptance of FMTLE 250 and FMTLE 500 for consumer consumption. In sum, combining TLE and probiotics in fermented beverages provides an excellent food model with many health benefits.