Metabolite Profiling and Antimicrobial Activities of Brassica rapa ssp. narinosa (Tatsoi), Brassica rapa var. narinosa × chinensis (Dacheongchae), and Brassica rapa ssp. chinensis (Pakchoi).

Pakchoi and Tatsoi are agriculturally and commercially important subspecies of Brassica rapa. Dacheongchae is a new crop generated via the hybridization of Tatsoi and Pakchoi. Metabolite profiles of carbohydrates, sugar alcohols, amines, amino acids, carotenoids, phenolics, organic acids, and glucosinolates were carried out in the three B. rapa cultivars. The majority of amino acids were higher in Dacheongchae than in Pakchoi and Tatsoi. In addition to the amino acid content, higher contents of phenolic compounds and carotenoids were obtained in Dacheongchae. Similarly, Dacheongchae and Pakchoi contained higher amounts of glucosinolates compared with Tatsoi. Pakchoi, Tatsoi, and Dacheongchae showed marked antimicrobial activity against Bacillus cereus, Escherichia coli, Candida albicans, Pseudomonas aeruginosa, Proteus mirabilis, and methicillin-resistant P. aeruginosa. Furthermore, Dacheongchae extracts exhibited only the inhibition activity of Salmonella paratyphi. Consistent with these higher amounts of bioactive compounds, Dacheongchae exhibited higher antimicrobial activities, suggesting synergistic antimicrobial properties from these bioactive compounds in Dacheongchae.