Carrot cell-wall studies

Liners, F., Van Cutsem, P. (1992). Distribution of pectic polysaccharides throughout walls of suspension-cultured carrot cells - An immunocytochemical study. Protoplasma, 170,10-21. 

We have proposed that the binding of bile acids to carrot fiber, or cell wall residue rich in pectin, may involve salt linkages between calcium pectate and the carboxylate group of the bile acid. This report presents studies that furnish additional evidence that calcium pectate does have a role in the binding of bile acids to carrot fiber. 

In our studies on the polysaccharide constituents of carrots and apples the following considerations have been borne in mind (i) that account must be taken of the readily soluble as well as of the more obviously fibrous non-starchy polysaccharides (11) that cell wall materials must be prepared with minimum loss of these more readily soluble polysaccharides (ill) Chat broad spectrum analyses of pectlc substances and hemlcelluloses, even when supported by determinations of Individual sugar components, are rarely sufficient to establish the nature of these substances since the same sugar constituents occur In quite... 

In studies on the biosynthesis of cell-wall polysaccharides in cultured carrot cells, D-glucose was only incorporated into the neutral sugar residues, particularly cellulose, whereas myo-inositol appeared in the uronic acid and pentose residues. " An increase in cellulose content was observed during the thickening of the cell walls of parenchymous tissue of Discorea dumetorum tubers during storage. 

In recent studies, Roman et al. showed that the distribution of polyacetylenes within the phloem tissue is not uniform and areas with high amounts of these compounds may also occur occasionally [17]. In addition, the authors could not find higher concentration of polyacetylenes close to the periderm. Significant amounts of falcarindiol detected in wild carrot species are related to their resistance to some plant diseases such as root knot nematodes. Raman mapping was also used to assess the distribution of lignin and polysaccharide substances in carrot tissues. Based on the results obtained, the individual accumulation of starch and cell wall components such as lignin, pectin, and cellulose could be successfully demonstrated. 

The wall material of plant cells is one of their distinguishing characteristics. As a result, lignin, cellulose, and other wall constituents have been studied in many plant tissue cultures. Phenylpropanoids. for example, have been shown lo be precursors of lignin formation in while pine. Set/noiii. lilac, rose, carrot, and geranium tissue cultures. Moreover, the biosynthesis of lignin has been shown to be alTeeted by kinetin. boron, and major elements, such as calcium. 

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