Antibacterial and Antioxidant Properties of Extracts of Yucca Baccata, a Plant of Northwestern Mexico, against Pathogenic Bacteria

Abstract

Introduction. Bacterial agents and oxidative reactions are involved in health and food preservation issues, and Yucca baccata (Y. baccata) can be a source of compounds with practical applications in both areas, but its investigation remains limited. Materials and Methods. Butanolic (YBE) and aqueous (YAE) extracts were obtained from the stem of Y. baccata. The total saponin, phenolic, and flavonoid contents were analyzed in the YBE and YAE. The antioxidant capacity of the extracts was determined by the DPPH, TEAC, FRAP, and ORAC assays. Seven Gram-positive and five Gram-negative pathogenic bacteria strains were used to determine the MIC and MBC. Results. Saponin contents were 30% and 1.81% (w/w) in the YBE and YAE, respectively. The total phenolic and flavonoid contents in the extracts were 29.5 μg GAEmg-1 (2.95%) and 5.58 μg GAEmg-1 (0.56%) in the YBE and 69.92 μg QEmg-1 (7.0%) and 1.65 μg QEmg-1 (0.165%) in the YAE. The antioxidant capacity values of YBE were 29.18 μg TEmg-1, 121.8 μg TEmg-1, 33.41 μg TEmg-1, and 156.84 μg TEmg-1 by the DPPH, TEAC, FRAP, and ORAC assays, respectively. YAE had lower antioxidant values than YBE ( $P<0.05$ ). Values of 80 mgmL-1 and 100 mgmL-1 were estimated for MIC and MBC of YBE against the Gram-positive bacteria. Values of 100 mgmL-1 and 120 mgmL-1 for MIC and MBC of YBE were estimated against the Gram-negative bacteria. No MIC and MBC were obtained for YAE. Conclusion. YBE exhibited higher antioxidant activity than YAE. Apparently, antibacterial properties of the YBE tended to be higher than those of the YAE.