Comparetive of Antioxidat and Antibacterial Activities of Aqueous and Acidic Extracts from Artemisia argyi
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
In order to compare the antioxidant and antibacterial effects of the aqueous extract and acidic extract of Artemisia argyi. Deionized water and citric acid solution were used to obtain two extracts from Artemisia argyi, and the contents of total flavonoids, total polyphenols and polysaccharides in these extracts were measured. The antioxidant capacity of each extract was evaluated by the DPPH, hydroxyl and ABTS radical scavenging assays. The Oxford cup method was used to determine the antibacterial activity of the extract and examine the underlying antibacterial mechanism. The results showed that the contents of total flavonoids, total polyphenols and polysaccharides were 208.03, 51.77 and 398.72 mg/g, respectively, in the aqueous extract of Artemisia argyi, and 80.39, 25.44 and 453.45 mg/g, respectively, in its acidic extract. Within a certain concentration range, both the aqueous extract and acidic extract of Artemisia argyi had strong antioxidant capacities, with their median inhibition concentration (IC50) values 33.10 and 54.52 μg/mL, respectively, for DPPH radical, 2.92 and 1.63 mg/mL, respectively for hydroxyl radical, 0.17 and 0.32 mg/mL, respectively, for ABTS radical. The aqueous extract of Artemisia argyi exhibited insigficant antibacterial effect; whilst the acidic extract exerted significant antibacterial activity against Staphylococcus aureus, Shigella and Salmonella, with the minimum inhibitory concentration being 0.10, 0.10 and 0.20 g/mL, respectively. The examinations of antibacterial kinetics and cell membrane permeability confirmed that the acidic extract could effectively inhibit the growth of pathogenic bacteria and change the cell membrane permeability. Scanning electron microscopy and polyacrylamide gel electrophoresis experiments revealed that the acidic extract can destroy the morphology of bacterial cell walls and inhibit bacterial protein synthesis. The extraction using the citric acid solution is more suitable for the extraction of the active ingredients from Artemisia argyi than the aqueous extraction, and the acidic extract has a greater potential as food preservatives and antioxidants.
