Antioxidant and antimicrobial activities of black Doraji (Platycodon grandiflorum)

Abstract

This study was conducted to investigate the antioxidant and antimicrobial activities of the hot-water and methanol extracts of raw and black Doraji to increase its utilization. In order to prepare the black Doraji, it was steamed for 15 days at a temperature of 60℃ and then it was dried at a temperature of 30℃ for 3 hr. The methanol extract from the black Doraji (BM) contained the highest levels of total polyphenols among the extracts, and the total polyphenol content of the extract from a black Doraji was higher than that of the extract from a raw Doraji. The total flavonoid contents of the hot-water extract from a black Doraji (BW) was the highest (7.94 mgQE/g) among the samples. The DPPH and ABTS radical scavenging activities increased according to the increase in the concentrations of the Doraji extracts. The BM has the highest radical scavenging activity among the extracts. Each extract showed a slight difference in the antibacterial activity according to the tested strains. The Black Doraji showed a higher antimicrobial activity compared to the raw Doraji. The hot-water extracts demonstrated higher activities than the methanol extracts, and the BW revealed the strongest activity. In this study, the black Doraji showed more effect of the antioxidant and anti-microbial activities than the raw Doraji. These results will provide fundamental data for improving the sitological value and the black Doraji can be used as a valuable resource for the development of nutraceutical foods.

Platycosides from the Roots of Platycodon grandiflorum and Their Health Benefits

“…Lee et al ( 46 ) investigated the antioxidant and antimicrobial activities of hot-water and methanol extracts of raw and black PG. The antimicrobial activities of PG extracts were studied against bronchus disease bacteria (i.e., Mycobacterium sp., Staphylococcus aureus , Klebsiella pneumoniae , Corynebacterium diphtheriae , and Streptococcus pyogenes ) and food poisoning bacteria (i.e., Escherichia coli O157:H7 and Bacillus cereus ).…”

Probiotic Properties of Pediococcus pentosaceus JBCC 106 and Its Lactic Acid Fermentation on Broccoli Juice

“…Antioxidant activity was measured by 2,2′-Azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging activity, and superoxide dismutase (SOD) activity as follows. ABTS radical scavenging activity was determined as described by Lee et al [ 27 ], with some modifications. The ABTS solution (1 mL) was mixed with 3 mL LAB samples and reacted for six minutes.…”

Metabolite Profile and Immunomodulatory Properties of Bellflower Root Vinegar Produced Using Acetobacter pasteurianus A11-2

“…It has also been reported that the antibacterial effect of vinegar is due to the presence of organic acids, such as acetic acid and lactic acid. Moreover, bellflower roots are also known to contain several phenolic compounds, such as flavonoids, polyphenols, and saponins (e.g., platycodin) [32]. According to Medina et al [33], compared with aqueous extracts of wine, olive oil, and other beverages, vinegar has the strongest inhibitory effect against all tested pathogens.…”