Determination of antioxidants and total polyphenols in cabbages (Brassica oleracea) irrigated with wastewater contaminated with toxic metals

• DOI: 10.22533/at.ed.3173352319102

• Palavras-chave: Águas residuais urbanas tratadas, Brassica Oleracea, Metais tóxicos

• Keywords: Treated Urban Wastewater, Brassica Oleracea, Toxic Metals

• Abstract: Water is a natural resource essential to all kinds of life. The reuse of treated wastewater (TWW) for irrigation is a possibility with challenges to be clarified at scientific level, in particular, its use in irrigation activities due to the eventual contamination of vegetables, like cabbages (Brassica oleracea), by toxic metals and other compounds harmful to humans present in these waters. On the other hand, the use of TWW for vegetable irrigation may allow significant water saving and also providing the cultivated species with nutrients, which may dispense the use of fertilizers. In this work, vegetables such as Brassica oleracea (cabbage), were planted in a greenhouse with a controlled environment (temperature and humidity) located at ISEL campus. Part of the vegetables was irrigated with tap water, and another part with TWW from two wastewater treatment plants (WWTP) located in Lisbon´s District. One of the WWTP receives only domestic wastewater (A), whilst the other one receives industrial and domestic wastewater (B). The antioxidant activity of the vegetable species as well as total content of polyphenols and flavonoids present in plant extracts were determined in order to assess the impact of using TWW contaminated with toxic metals in their irrigation.