Arugula is a popular variety of greens, which encompasses a number of plant species. The plants all contain mustard oil glycosides that give them a spicy, bitter flavor. There are two main kinds of arugula that grow in nature; however, you must be careful when eating the wild variety called perennial wall rocket. In contrast to the kind that has been cultivated, the wild variety contains higher amounts of erucic acid, which can be harmful at concentrations above 5 %.
From Wikipedia: “Eruca sativa (syn. E. vesicaria subsp. sativa (Miller) Thell., Brassica eruca L.) is an edible annual plant, commonly known as rocket salad or arugula; other names include rucola, rucoli, rugula, colewort, and roquette.
It is sometimes conflated with Diplotaxis tenuifolia, known as perennial wall rocket, another plant of the Brassicaceae family that is used in the same manner. Eruca sativa, which is widely popular as a salad vegetable, is a species of Eruca native to the Mediterranean region, from Morocco and Portugal in the west to Syria, Lebanon, and Turkey in the east.
“Arugula contains high levels of mustard oils (isothiocyanates bound in the form of mustard oil glycosides). These are responsible for arugula’s aromatic and bitter flavor. Argula is recommended for people who have hypothyroidism as it contains high amounts of iodine. Arugula is also a good source of glucosinolates, beta-carotene, and folic acid.
As with spinach and mixed greens, under certain circumstances (e.g., improper use of fertilizers) arugula contains extremely high levels of nitrates. This has been shown in samples taken by the Bayerischen Landesamts für Gesundheit und Lebensmittelsicherheit (Bavarian state office for health and food safety).*”
If you eat arugula and other foods high in nitrates regularly and your drinking water also contains high levels, you may be exceeding the recommended intake of nitrates. It is best to consume arugula and other vegetables high in nitrates in moderation.
“In Italy, raw rocket is often added to a pizza at the end of or just after baking. It is also used cooked in Apulia, in Southern Italy, to make the pasta dish cavatiéddi, "in which large amounts of coarsely chopped rocket are added to pasta seasoned with a homemade reduced tomato sauce and pecorino", as well as in "many unpretentious recipes in which it is added, chopped, to sauces and cooked dishes" or in a sauce (made by frying it in olive oil and garlic) used as a condiment for cold meats and fish. In the Slovenian Littoral, it is often combined with boiled potatoes, used in a soup, or served with the cheese burek, especially in the town of Koper. It is also used with salad, tomatoes and mozzarella cheese. ...
In Brazil and Argentina, where its use is widespread, rocket is eaten raw in salads. A popular combination is rocket mixed with mozzarella cheese (normally made out of buffalo milk) and sun-dried tomatoes.
In Cyprus, the plant is used in salads and omelets. An omelet with arugula (Greek rokka) is common in Cypriot restaurants. ...
In Egypt, the plant is commonly eaten raw as a side dish with many meals, with ful medames for breakfast, and regularly accompanies local seafood dishes.
In Turkey, similarly, the rocket is eaten raw as a side dish or salad with fish, but is additionally served with a sauce of extra virgin olive oil and lemon juice.
In West Asia and Northern India, Eruca seeds are pressed to make taramira oil, used in pickling and (after aging to remove acridity) as a salad or cooking oil. The seed cake is also used as animal feed.”
“The Latin adjective sativa in the plant's binomial is derived from satum, the supine of the verb sero, meaning "to sow", indicating that the seeds of the plant were sown in gardens.
Other common names include garden rocket, or more simply rocket (British, Australian, South African, Irish and New Zealand English), and eruca. The English common name, rocket, derives from the French roquette, a diminutive of the Latin word eruca, which designated an unspecified plant in the Brassicaceae family (probably a type of cabbage).
Arugula (/əˈruːɡələ/), the common name now widespread in the United States and Canada, entered American English from non-standard (dialect, dictionary English) Italian. The standard Italian word is rucola, a diminutive of the Latin "eruca". The Oxford English Dictionary dates the first appearance of "arugula" in American English to a 1960 New York Times article by food editor and prolific cookbook writer Craig Claiborne.”
Note (italics): * = Translation from a German Wikipedia entry