Wild mustard (Sinapis arvensis) parts: compositional analysis, antioxidant capacity and determination of individual phenolic fractions by LC–ESI–MS/MS

Abstract

This study aimed to evaluate bioactivity related properties of wild mustard parts (WMP) including the leaves, flowers, stems, fruits, and seeds. The biomass and ion composition of WMP were analyzed by elemental analyzer and ion chromatography, respectively. Extraction conditions of phenolics were optimized with Response Surface Methodology by taking into consideration 3 factors such as the ratio of ethanol to water, temperature, and time. LC–ESI–MS/MS was used for the identification of phenolics in WMP. The principal phenolic compounds in the leaves, flowers and seeds of wild mustard were kaempferol, hydroxycinnamic acid, and catechin, respectively, whereas vanillic acid was dominant in the stems and fruits. The antioxidant capacities of WMP were 1.88–15.56, 309.61–775.63, 25.46–87.24, and 193.58–617.08 µmol TE/g for DPPH, ABTS, FRAP, and CUPRAC, respectively. Antioxidant capacity of the flowers was in all cases superior to the other parts irrespectively of the antioxidant capacity method being used. Therefore, the flower extract was transformed into powder in order to determine the potentiality of it as an ingredient for the enrichment of food formulations. Powdered flower extract (PFE) was incorporated into ice cream at the levels of 0.3–0.9%. The sensory scores indicated that PFE had almost no effects on texture related properties of ice cream, whereas overall acceptability of PFE enriched ice creams decreased as the amount of PFE increased. PFE also showed antimicrobial activity on selected food-borne pathogens, most notably on Staphylococcus haemolyticus. Wild mustard can be evaluated as a source of natural phenolic antioxidant compounds in different industries.