Envolvimento das reações hidrolíticas na deterioração das sementes de Moringa oleifera Lam. durante o armazenamento

Abstract

The aim of this work was to investigate the deterioration of Moringa oleifera Lam. (moringa) seeds during storage under controlled conditions. Seeds were conditioned in semipermeable plastic bags and stored in a growth chamber (27 ± 2 ºC and RH 65%) and in a refrigerator (4 ± 2 ºC and RH 25%) for 18 months. Harvests were performed prior to storage and every 3 months. Water content, germination percentage, mean germination time, seedling length and dry weight, and content of neutral lipids, starch, soluble proteins, total soluble sugars, non- reducing sugars, and total free amino acids, as the activity of lipases, amylases and acid proteases were evaluated. Water content, viability, and vigor remained unchanged, as well as the content of neutral lipids, starch, total soluble sugars, non-reducing sugars, and total free amino acids did not decrease in the seeds stored under refrigeration during 12 months. The content of soluble proteins decreased progressively over time, regardless of the storage environment. Viability and vigor loss was accompanied by a decrease in the content of neutral lipids, soluble proteins, total soluble sugars and non-reducing sugars and an increase in the activity of lipases and acid proteases in the seeds stored in the growth chamber and in the refrigerator. The role of enzymatic and non-enzymatic hydrolysis in deterioration of food reserves during natural aging is discussed. For cultivation purposes, moringa seeds should be stored under refrigeration at low relative humidity for up to 12 months.