Panarat Laohabutr. Iron, vitamin C, phytate and crude fiber contents in northeastern local vegetables. Master's Degree(Food Chemistry and Medical Nutrition). Chulalongkorn University. Office of Academic Resources. : Chulalongkorn University, 2000.
Iron, vitamin C, phytate and crude fiber contents in northeastern local vegetables
Abstract:
Food iron is existed in two forms, heme iron is found in meat, fish and poultry; nonheme iron is found in cereal, vegetable and fruit. The absorption of heme iron is higher than that of nonheme iron. The absorption of nonheme iron can be enhanced or inhibited by various dietary components. The major enhancer of nonheme is vitamin C; the major inhibitors are phytate and fiber. This study determined iron, vitamin C, phytate, crude fiber and iron bioavailability contents in northeastern local vegetables. Iron, the highest was found in Marsilea crenata Presl (62.49 mg/100g dry weight) while the lowest was found in Colocasia gigantea Hook. f.(0.93 mg/100g dry weight). Vitamin C, the highest was found in Tiliacora triandra diels (164.68 mg/100g wet weight) while the lowest was found in Wolffia globosa Hartog & Plas (8.69 mg/100g wet weight). For phytate, the highest was found in Sesbania grandiflora (L.) Pers (1184.56 mg/100g dry weight) while the lowest was found in Tiliacora triandra diels (32.66 mg/100g dry weight). Crude fiber, the highest was found in Tiliacora traindra diels (6.56 g/100g dry weight) while the lowest was found in Wolffia globosa Hartog & Plas (0.48 g/100g dry weight). The positive significant correlation was found between vitamin C and crude fiber (P<0.05). In contrast, the negative significant correlation was found between iron and phytate (P<0.01). Iron bioavailability, the highest was found in Marsilea crenata Presl (3.05 and 1.13 mg/100g by Monsen's and Tseng's method, respectively) while the lowest was found in Colocasia gigantea Hook. f. (0.04 and 0.0076 mg/100g by Monsen's and Tseng's method, respectively). The mean of iron bioavailability from the Monsen's and Tseng's method was 0.73+-0.68 mg/100g and 0.24+-0.26 mg/100g, respectively. The calculated iron bioavailability by Monsen's method was higher than that by Tseng's method because Monsen's method was considered only the effect of enhancing factor; while Tseng's method was involved both the effects of enhancing and inhibiting factor. The result of these studies would be meaningful for being a background data of studying in nutritional aspect and selecting consumption in order to meet adequate dietary iron.