A Comparative Study on the Total Antioxidant and Antimicrobial Potentials of Ethanolic Extracts from Various Organ Tissues of Allium spp.

Abstract

The extracts from different tissues of Allium fistulosum L. and Allium sativum L. were investigated to evaluate their antioxidant and antimicrobial capacity. The highest yields of the Allium extracts were prepared from the extraction of 30% ethanol solution. The DPPH scavenging activity was the highest in A. fistulosum L. leaves, which IC50 is 14.61 μg·mL-1. The highest antioxidant activity using TEAC assay and total phenolic content were observed in A. sativum L. stems and A. fistulosum L. stems, where they are determined to be 15.51 mMand 191.04 mg GAE·g-14.59 mMand 182.60 mg GAE·g-1,respectively. Statistic analysis revealed that the DPPH IC50 value was significantly correlated with total phenolic contents and antioxidant activity using TEAC assay. The extracts of A. sativum L. bulbs were found to exhibit antimicrobial activity against Staphylococcus aureus with the MIC and MBC of 0.2 mg·mL-1and 0.4 mg·mL-1, respectively. In addition, the extract of A. fistulosum L. stems was more active against Bacillus subtilis, with an MIC and MBC of 0.2 and 0.4 mg·mL-1, respectively. The inhibitory activity of various Allium extracts against the test bacteria was greater than that of 10 μg·mL-1 allicin. The results indicated that Allium spp. extracts could be used as a potential source of natural antioxidants and antimicrobial agents.