Levels of metals and nutritional composition of garden cress (Lepidium sativum) seed, in Southern Ethiopia

Garden cress (Lepidium sativum) belongs to the Cruciferae family, a fast-growing edible herbaceous plant. This study aimed to determine the essential and non-essential metals levels and nutritional composition of garden cress seed grown in the Wolaita Zone in southern Ethiopia. The study was carried out by collecting garden cress cultivated in Jage, Wandara, Taba, Hilena, Siyara, Demba Gale, Himbecho, Afama and Gara sites of the Wolaita Zone, Southern Ethiopia.

27 triplicate garden cress seed samples were collected from nine selected sites and digested by the wet digestion method. The level of metals in the sample was determined by using FAAS.

The result showed that the average concentration of K, Ca, Mg, Fe, Cu and Zn in the garden cress seed samples in mg/100 g dry weight, were in the range of 1179.76 to 1226.79, 249.52 to 291.62, 314.84 to 341.44, 7.29 to 8.48, 3.72 to 5.44 and 5.80 to 6.68, respectively. The average concentration of non-essential lead metal was not detected in all sample sites. The proximate composition of the garden cress seed sample was in the range of 19.68% to 22.87% for protein, 8.30% to 10.27% for crude fiber, 20.72% to 24.17% for fat, 3.44% to 4.63% for ash, 1.37% to 2.59% for moisture, 40.56% to 43.24% for carbohydrate and 332.96 to 344.19 Kcal/100 g for energy. The study confirmed that the garden cress seed was a good source of essential metals and an excellent source of protein, carbohydrate, fiber, energy and fat contents. The concentrations of metals in garden cress were permissible compared with recommended permissible limits of WHO/FAO as well as USDA.