Influence of Drought and Heat Stress on Mineral Content, Antioxidant Activity and Bioactive Compound Accumulation in Four African Amaranthus Species

Autor: Mmbulaheni Happiness Netshimbupfe, Jacques Berner, Frank Van Der Kooy, Olakunle Oladimeji, Chrisna Gouws
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Plants, Vol 12, Iss 4, p 953 (2023)
Druh dokumentu: article
ISSN: 2223-7747
DOI: 10.3390/plants12040953
Popis: Drought and heat stress is known to influence the accumulation of mineral content, antioxidant activity, phenolics, flavonoids and other bioactive compounds in many tolerant leafy vegetables. Amaranthus plants can tolerate adverse weather conditions, especially drought and heat. Therefore, evaluating the influence of drought and heat stress on commercially and medically important crop species like Amaranthus is important to grow the crop for optimal nutritional and medicinal properties. This study investigated the influence of drought and heat stress and a combination of both on the accumulation of phenolic and flavonoid compounds and the antioxidant capacity of African Amaranthus caudatus, A. hypochondriacus, A. cruentus and A. spinosus. Phenolic and flavonoid compounds were extracted with methanol and aqueous solvents and were quantified using liquid chromatography with tandem mass spectrometry (LC-MS/MS). Caffeic acid was the main phenolic compound identified in aqueous extracts of A. caudatus and A. hypochondriacus. Rutin was the most abundant flavonoid compound in all the Amaranthus species tested, with the highest concentration found in A. caudatus. The results suggest a strong positive, but species and compound-specific effect of drought and heat stress on bioactive compounds accumulation. We concluded that heat stress at 40 °C under well-watered conditions and combined drought and heat stress (at 30 °C and 35 °C) appeared to induce the accumulation of caffeic acid and rutin. Hence, cultivation of these species in semi-arid and arid areas is feasible.
Databáze: Directory of Open Access Journals