Metabolic Conversion of l-Ascorbic Acid to Oxalic Acid in Oxalate-accumulating Plants

Yang, Joan C.; Loewus, Frank A.

doi:10.1104/pp.56.2.283

Cited by 91 publications

(45 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The oxalate production pathways the cleavage of isocitrate, hydrolysis of oxaloacetate, glycolate/glyoxylate oxidation, and/or oxidative cleavage of L-ascorbic acid (Hodgkinson, 1977). Of these pathways, the cleavage of ascorbic acid appears to be the most common (Yang & Loewus, 1975;Nuss & Loewus, 1978;Li & Franceschi, 1990;Keates et al, 2000).…”

Section: Introductionmentioning

confidence: 99%

Oxalate Content of Egyptian Grown Fruits and Vegetables and Daily Common Herbs

Abdel-Moemin¹

2014

JFR

View full text Add to dashboard Cite

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 daily common herbs. The current study analysed the total and the soluble oxalate in 37 Egyptian grown fruits, vegetables and 9 commonly used herbs. Two methods were used for screening the Egyptian foods for oxalate concentration; the first method was AOAC 1999 and the second was enzymatic method.

show abstract

Section: Introductionmentioning

confidence: 99%

Oxalate Content of Egyptian Grown Fruits and Vegetables and Daily Common Herbs

Abdel-Moemin¹

2014

JFR

View full text Add to dashboard Cite

show abstract

“…These pathways include the cleavage of isocitrate, hydrolysis of oxaloacetate, glycolate/glyoxylate oxidation, and/or oxidative cleavage of L-ascorbic acid (Hodgkinson, 1977). Of these pathways, the cleavage of ascorbic acid appears to be the most attractive (Yang and Loewus, 1975;Nuss and Loewus, 1978;Li and Franceschi, 1990;Keates et al, 2000). Once produced, the oxalate then combines with calcium to generate the vast variety of observed crystal shapes and sizes.…”

mentioning

confidence: 99%

Isolation of Medicago truncatula Mutants Defective in Calcium Oxalate Crystal Formation

Nakata

McConn

2000

Plant Physiology

View full text Add to dashboard Cite

Plants accumulate crystals of calcium oxalate in a variety of shapes, sizes, amounts, and spatial locations. How and why many plants form crystals of calcium oxalate remain largely unknown. To gain insight into the regulatory mechanisms of crystal formation and function, we have initiated a mutant screen to identify the genetic determinants. Leaves from a chemically mutagenized Medicago truncatula population were visually screened for alterations in calcium oxalate crystal formation. Seven different classes of calcium oxalate defective mutants were identified that exhibited alterations in crystal nucleation, morphology, distribution and/or amount. Genetic analysis suggested that crystal formation is a complex process involving more than seven loci. Phenotypic analysis of a mutant that lacks crystals, cod 5, did not reveal any difference in plant growth and development compared with controls. This finding brings into question the hypothesized roles of calcium oxalate formation in supporting tissue structure and in regulating excess tissue calcium.

show abstract

“…We therefore investigated the biosynthesis of oxalate to obtain information about the possibility of reducing the production of oxalate in spinach. Glyoxylate, glycolate, and ASA are the precursors of oxalate as indicates by feeding experiments in many plants (Chang and Beevers 1968;Seal and Sen 1970;Yang and Loewus 1975;Williams et al 1979;Chang and Huang 1981). The major part of glyoxylate may be produced from glycolate in the peroxisomes in green spinach leaves.…”

mentioning

confidence: 99%

Kate of oxalate biosynthesis from glycolate and ascorbic acid in spinach leaves

Fujii

Watanabe

et al. 1993

Soil Science and Plant Nutrition

View full text Add to dashboard Cite

The contribution of glycolate as a precursor of oxalate in newly expanding spinach leaves was compared with that of L-ascorbic acid (ASA). Detached spinach leaves were fed with [2-14C]glycolate and [1-1~C]ASA. Using the values of the rate of photorespiratory glycolate synthesis and the incorporation of glycolate-~C into oxalate, the rate of oxalate biosynthesis via glycolate amounted to 34 ~g g-1 fr wt h -1 under light conditions. When the values of incorporation of ASA-14C into oxalate and the turnover rate of ASA were used, the rate of oxalate biosynthesis via ASA in light and darkness, amounted to 1.6 and 2.9 #g g-1 fr wt h -1, respectively. Glycolate was found to be more efficient as a precursor of oxalate than ASA in newly expanding spinach leaves.Key Words: glycolate, L-ascorbic acid, oxalate biosynthetic rate, photorespiration, spinach.Spinach is an edible plant species belonging to the family Chenopodiaceae. Oxalate accumulates in spinach leaves and a high-oxalate diet can increase the risk of formation of calcium oxalate stones in kidneys (Hodgkinson 1978) and may also affect calcium absorption (Liebman and Doane 1989). Plants which produce calcium oxalate are known to induce a painful sensation in the mouth when eaten (Perera et al. 1990). Oxalate may, therefore, contribute to the harsh taste of spinach and it is thus necessary to produce spinach with a low oxalate content. Many attempts have been made to reduce the level of oxalate in spinach leaves with regard to nitrogen and inorganic ion availability as well as other growth conditions (Watanabe et al. 1987;lwanami 1989;Zhang et al. 1990). However, oxalate biosynthesis has not been well documented. We therefore investigated the biosynthesis of oxalate to obtain information about the possibility of reducing the production of oxalate in spinach. Glyoxylate, glycolate, and ASA are the precursors of oxalate as indicates by feeding experiments in many plants (Chang and Beevers 1968;Seal and Sen 1970;Yang and Loewus 1975;Williams et al. 1979;Chang and Huang 1981). The major part of glyoxylate may be produced from glycolate in the peroxisomes in green spinach leaves. The presence of a barrier to glyoxylate transportation in peroxisomal membranes, and compartmentation have been reported (Liang and Huang 1983;Heupel et al. 1991). As external application of glyoxylate for metabolic studies is not suitable, we compared the contribution of glycolate Abbreviations: ASA, k-ascorbic acid; fr wt, flesh weight; mol wt, molecular weight. or ASA as a precursor of oxalate biosynthesis in spinach leaves. MATERIALS AND METHODSUsing the values of the rate of photorespiratory glycolate synthesis and the incorporation of glycolate-14C into oxalate, the rate of oxalate biosynthesis via glycolate was calculated as follows:Rate of glycolate synthesisX incorporation of glycolate-14C into oxalate X tool wt of oxalate/mol wt of glycolate, (formula 1) and the following formula was used to calculate oxalate biosynthesis via ASA using the values of ASA-~4C incorporation into oxalate...

show abstract

Metabolic Conversion of l-Ascorbic Acid to Oxalic Acid in Oxalate-accumulating Plants

Cited by 91 publications

References 25 publications

Oxalate Content of Egyptian Grown Fruits and Vegetables and Daily Common Herbs

Oxalate Content of Egyptian Grown Fruits and Vegetables and Daily Common Herbs

Isolation of Medicago truncatula Mutants Defective in Calcium Oxalate Crystal Formation

Kate of oxalate biosynthesis from glycolate and ascorbic acid in spinach leaves

Contact Info

Product

Resources

About