This study identified phenolic compounds from mustard seed meal and characterized their antibacterial activity. Phenolic compounds were extracted from defatted Oriental mustard (Brassica juncea L.) seed meal and characterized using ultra-high-performance liquid chromatography with diode array and electrospray ionization-mass spectrometric detection (UHPLC-DAD-ESI-MSn ). Sinapic acid and several sinapoyl conjugates were identified based on retention time, UV spectra, MS fragmentation pattern, and by comparison with the authentic sinapic acid reference substance. The crude extract and a purified phenolic fraction exhibited selective antibacterial effects against Gram-negative and Gram-positive spoilage bacteria including Staphylococcus aureus and Listeria monocytogenes; Lactobacillus plantarum was resistant. After alkaline hydrolysis, only sinapic acid could be detected, enabling quantification with the authentic reference substance. Alkaline hydrolysis released 2.66 ± 0.00 mg sinapic acid g−1 dry matter defatted mustard seed meal. Minimum inhibitory concentrations of the hydrolyzed extract against Bacillus subtilis, Escherichia coli, L. monocytogenes, Pseudomonas fluorescens, and S. aureus were 0.1 g L−1 or less. Growth of L. plantarum remained unaffected. Sinapic acid and sinapoyl esters are generally found in members of the Brassicaceae family. Methods for their fast identification will be useful in chemotaxonomic studies. The release of sinapic acid after alkaline hydrolysis not only allows for the quantification using the reference substances but also facilitates the standardization of the antibacterial activity of plant extracts for use as food preservative.
Christina Engels, Andreas Schieber, Michael G. Gänzle
Endothelial nitric oxide synthase polymorphism G298T in association with oxidative DNA damage in coronary atherosclerosis
Content Type Journal Article
Category Research Note
RAJESH G. KUMAR, Department of Genetics, Osmania Univers ... more
A micropropagation protocol was developed for multiplication of seedless lemon (Citrus limon L. cv. Kaghzi Kalan) using nodal explants. The maximum shoot regeneration was observed on low level of BAP (0.1 mg l−1) or kinetin (0.5 mg l−1). BA was recorded to be better than kinetin in terms of ... more
The objective of this study was to evaluate the activity, kinetic behavior, and thermal inactivation kinetics of peroxidase (POD) in aqueous extracts from two kinds of milk ripe stage corn, sweet corn and waxy corn. Optimum activities using guaiacol as the hydrogen donor were obtained for s ... more