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Preliminary Assessment of Lotus (Nelumbo nucifera Gaertn.) Rhizomes: An Underutilized Aquatic Vegetable Crop




Wang, Xu

Type of Degree





Lotus (Nelumbo nucifera Gaertn.) is a perennial aquatic edible plant which offers a wide diversity of potential health benefits including improving learning and cognitive memory, anti-obesity activity, anti-HIV activity, anti-tumor activity, diuretic activity, antipyretic activity, anti-inflammatory activity and anti-diabetic activity. Determination of the optimum physiological maturity of edible lotus rhizome is unclear and problematic. In order to establish a reliable maturity index for two edible lotus species (N. nucifera ‘E2’ and N. lutea) we have evaluated the changes in various phytochemical parameters during four consecutive harvest determinations. Therefore, the global objectives of this study were to determine the effects of harvest maturity on lotus rhizome nutritional quality and to possibly establish a reliable harvest index. The proposed senescence indicators (chlorophyll content index (CCI), dry matter content (DMC), hydrogen peroxide (H2O2), malondialdehyde (MDA) and total soluble protein (TSP) content), in conjunction with phytochemical antioxidant metabolites (ascorbic acid, (AsA), proline (Pro), total phenols (TP) and antioxidant capacity (ABTS and DPPH)) in leaves and rhizomes from two edible species of lotus (N. nucifera ‘E2’ and N. lutea) were determined at four harvest dates during growing season to establish objective criteria for estimating optimal commercial harvest maturity. Significant differences were found among harvest dates for senescence indicators and phytochemical antioxidant components. A potential maturity index (chlorophyll content) was established for N. nucifera rhizomes to provide optimal nutritional quality and consumer demand. In addition, N. lutea was considered as an early maturing species when compare with N. nucifera ‘E2’ based on proposed objective criteria evaluated.