Eruca

Eruca vesicaria subsp. sativa is a fast-growing annual with lobed, peppery leaves, cream or yellow flowers marked with purple veins, and slender upright pods. The small round seeds, about 1.5 to 2 millimeters across, are reddish-brown to yellowish and arranged in two rows inside each pod. When crushed, they release a sharp, mustard-like pungency with a nutty undertone. Seeds are sold for planting arugula greens and microgreens, and in India as an oilseed. The plant grows well in dry, cool conditions and on poor soils, and it matures quickly. Pressed taramira oil is dark yellow to brown, strongly pungent, and often needs aging to mellow its taste.

Eruca vesicaria is native to the Mediterranean region, with the cultivated subspecies sativa widely grown from Southern Europe through North Africa and the Middle East to South Asia. The genus name Eruca comes from Latin and was used in antiquity for this plant, while the English names rocket and arugula come through French roquette and Italian rucola, from the same Latin root. In India and Pakistan the seed and oil are called taramira, derived from regional language names, and the plant is also known in Arabic as jarjir.

Arugula was known to the ancient Egyptians, Greeks and Romans, who ate the leaves as a salad plant and used the seeds as a flavoring. Roman writers praised or warned about its supposed stimulating effects, and the seeds were ground into spice mixtures, wine and sauces. Medieval herbals in Europe record it as a garden herb used both in kitchens and for home remedies.

In South Asia the plant became an important minor oilseed on dry, marginal land, especially in northwestern India, including Rajasthan, Haryana, Uttar Pradesh and Punjab, where it is sown after the monsoon on residual soil moisture. The oil, known as taramira or tara mira oil, was used for cooking after aging, for pickling, as a lamp oil and for massage and hair care. Its high erucic acid content and strong pungency limit its modern use for food in some countries, and it is often blended with mustard oil in traditional practice.

In recent decades arugula leaves have gone from a regional specialty to a global salad staple, and seed companies sell many varieties. Researchers continue to study eruca as a drought-tolerant oilseed and for glucosinolate-rich meal.

Seeds are used to sow arugula for salad leaves and microgreens, and a few cooks add them to sprouting mixtures for a peppery bite. In northern India, they are pressed for taramira oil, which is aged before cooking, and used in pickles and as a massage oil. The pressed cake is used as livestock feed after processing, or as an organic fertilizer. Traditional uses of the seeds in folk medicine include digestive and diuretic remedies. Ground seeds can also be used like mustard seed as a pungent condiment in small amounts.

Arugula leaves and seeds contain glucosinolates, sulfur compounds that are broken down into isothiocyanates, which give the sharp flavor and have been studied in laboratory and population research for possible protective effects, though evidence in humans is not conclusive. The seed oil is high in erucic acid, which has raised heart-related concerns in animal studies at high intakes. Arugula leaves are rich in vitamin K, folate and nitrates. Seeds are not a standard nutritional food.