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The chemical structure of different forms of oxalic acid 

The chemical structure of different forms of oxalic acid 

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Egyptian dieticians typically rely on foreign databases to find out oxalate content of food due to unavailability of local databases. The soil, fertilizers, climate and cultivars are often very different. Therefore, the purpose of this study is to establish a local database of oxalate content in Egyptian grown fruits and vegetables and selected dai...

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... They are grouped with fibers under the general term sclerenchyma. 18 Their walls consist of cellulose, hemicellulose and lignin. Sclerenchyma provides the main structural support to a plant. ...
... Oxalic acid (ethanedioic acid), and its salts occur as an end product of metabolism in a number of plants. Oxalate is associated with metabolic disorders and infectious diseases 18 . The crystals are especially common in the cells bounding the air chamber of stomata which certainly require some mechanical support. ...
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... In the edible parts of many commonly grown fruits the concentration of total oxalic acid (soluble + insoluble) is 0.02-0.6 mg g -1 FW (Noonan and Savage 1999; Nguyê ̃ n and Savage 2013a; D' Evoli et al. 2013Evoli et al. , 2015Abdel-Moemin 2014;Attalla et al. 2014;Cruz- Castillo et al. 2014). In other fruits the concentration of total oxalate can be moderate to very high: carambola (Averrhoa carambola L., star fruit; 4.36 mg g -1 FW), goji berries (Lycium barbarum L.; 1.38 mg g -1 FW) and Indian gooseberries (Phyllanthus emblica L.; 75.66 mg g -1 FW) (Nguyê ̃ n and Savage 2013a). ...
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... The curly leaf cultivar contained the highest % of soluble oxalate in both the leaves and stems when compared to the flat leaved cultivar ( Table 1). This study confirmed the earlier observation [4] that parsley stems contained significantly more oxalates than the leaves (total oxalates P < 0.001, soluble P < 0.01 and insoluble oxalates P < 0.05). Table 2 shows the total calcium and calcium bound in insoluble oxalate (mg/100 g DM) of the leaves and stems of flat leaf and curly leaf parsleys. ...
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... Oxalic acid (ethanedioic acid), and its salts occur as an end product of metabolism in a number of plants. Oxalate is associated with metabolic disorders and infectious diseases 18 . The crystals are especially common in the cells bounding the air chamber of stomata which certainly require some mechanical support. ...
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