Brassica spp. and Antimicrobial Power: A Review of MICs of Their Plant Extracts

Background/Objectives: Brassica spp. constitute an important group of edible plants. Over the last century, the important power of these plants as bioactive producers with anticancer, anti-inflammatory, antioxidant or cardioprotective properties has clearly been established. There are many species of this genus, with more than 34 species, as well as several subspecies. Brassica species also have antimicrobial properties, and this is an important aspect of this group. Therefore, the objective of this study was to explore the antimicrobial properties of extracts of different Brassica species. These aspects are important to consider in actual antimicrobial resistance crises and in terms of the possible modulation of the gut microbiota by these foods. Methods: A search of the scientific literature was carried out using the Scopus, Web of Science and Google Scholar databases. The search was carried out regarding antimicrobials as well as Brassica as the main initial term. From the great number of papers found, those with minimum inhibitory concentration (MIC) data and aspects such as the extraction procedure, as well as the proven microorganisms, were selected. Results: A total of 41 papers were selected from the literature. Most of them were from Brassica oleracea, with a total of 14 papers. There are differences between different species, as well as among the different parts of the plants, depending on the extraction procedure used to obtain the extracts. Conclusions: Higher antimicrobial power was detected for the extracts of Brassica rapa, whose best value was 0.25 µg/mL, when hydrodistillation or microwave hydrodistillation was used. Additionally, Brassica nigra (black mustard) showed the greatest inhibition when it was extracted in the vapor phase, with the best value of 0.012 µg/mL. No reviews regarding the MICs of Brassica extracts have been carried out until now.