Brassica vegetables include broccoli, cabbage, mustard and collard greens, and bok choy. They contain glucosinolates, the metabolic breakdown products of which are potent modulators of xenobiotic-metabolizing enzymes that protect DNA from damage. Almost all parts of some brassica species have been developed for food, including the root (swedes, turnips), stems (kohlrabi), leaves (cabbage, brussels sprouts), flowers (cauliflower, broccoli), and seeds (many, including mustard seed, rapeseed). Brassicaterol is found in high concentrations in brassica, also known as rapeseed oil.

Importance
Critical Reviews in Food Science and Nutrition. 2014. Brassica foods as a dietary source of vitamin C: a review. Brassica genus includes known horticultural vegetables with major economical importance worldwide, and involves vegetables of economical importance being part of the diet and source of oils for industry in many countries. Brassicales own a broad array of health-promoting compounds, emphasized as healthy rich sources of vitamin C. The adequate management of pre- and postharvest factors including crop varieties, growth conditions, harvesting, handling, storage, and final consumer operations would lead to increase or preserve of the vitamin C content or reduced losses by interfering in the catalysis mechanisms that remains largely unknown, and should be reviewed. Likewise, the importance of the food matrix on the absorption and metabolism of vitamin C is closely related to the range of the health benefits attributed to its intake. However, less beneficial effects were derived when purified compounds were administered in comparison to the ingestion of horticultural products such as Brassicas, which entail a closely relation between this food matrix and the bioavailability of its content in vitamin C. This fact should be here also discussed. These vegetables of immature flowers or leaves are used as food stuffs all over the world and represent a considerable part of both western and non-Western diets, being inexpensive crops widely spread and reachable to all social levels, constituting an important source of dietary vitamin C, which may work synergistically with the wealth of bioactive compounds present in these foods.

Brassica plant species
Brassica rapa - turnip rape
   Lipids Health Dis. 20142 .Compared with the intake of commercial vegetable juice, the intake of fresh fruit and komatsuna (Brassica rapa L. var. perviridis) juice mixture reduces serum cholesterol in middle-aged men: a randomized controlled pilot study.
Brassica napus - Oilseed rape
oleracea - Kale, Cabbage, Broccoli, Cauliflower, Kai-lan, Brussels sprouts
Brassica nigra - black mustard
juncea - brown mustard
Brassica hirta or brassica alba - white mustard