Sugar acids galacturonic acid

Monakhova et al presented validation studies for multieomponent quantitative NMR analysis of apple fruit juice that includes, apart from other compounds, such sugars as galacturonic acid, arbutin, fructose, glucose, sucrose, quinic acid, maltotriose, maltose and xylose. The NMR analysis can be used for quality control of different fruit juices. 

Principal polysaccharide constituent listed. Sugars are D- unless otherwise noted. Ara = arabinose Gal = galactose GalA = galacturonic acid ... 

Bromophenol blue (3.0...4.6) aliphatic carboxylic acids [225 — 228] malonic and lactic acids [229] palmitic and lactic acids [230] malonic, glycolic, malic, citric, tartaric, ketoglutaric, galacturonic and oxalic acids [196] dicarboxylic acids, succinic acid [231] indoleacetic acid, trichloroacetic acid [232] palmitic acid, palmityl- and stearyllactic acid [223] benzoic, sorbic and salicylic acid [234] metabolites of ascorbic acid [235] chloropropionic acid [236] oligogalacturonic acids [237] amino acids, hydrocarbons, mono-, di- and triglycerides [238] xylobiose, xylose, glucose and derivatives [239] sugar alcohols [91] toxaphene [240]... 

Deoxy-sugars. Part XXI. Synthesis of Some Derivatives of 2-Deoxy-D-galacturonic Acid, W. G. Overend, F. Shafizadeh, and M. Stacey, J. Chem. Soc., (1951) 1487-1489. 

The LPS from Proteus species contain amino acids linked as amides to acidic sugars. Thus, L-lysine is linked by way of N-6 to a D-galacturonic acid residue (52) in the LPS from P. hauseri, but by way of N-2 to a D-glucu-ronic acid residue in the LPS from P. mirabilis 027. The latter LPS also contains L-alanine, linked to the carboxyl group of a D-galacturonic acid residue. 

The length of the arabinan side chains present in subunit II may vary between 30 and 50 arabinose residues and several of these chains might be connected to the rhamnogalacturonan backbone which consists of only 8-10 sugar residues (ratio of rhamnose to galacturonic acid is 0.2 to 0.4). The arabinans might be connected directly to a rhamnose residue in the backbone or via one or more galactose residues [41]. 

Pectins is a general term for a group of natural polymers based on polymerized galacturonic acid partly esterified with methanol. In addition these polymers must be considered as copolymers due to existence of neutral sugar branched zones. [1]. Some uronic acid units may also be esterified on 0-2 or 0-3 position with acetic acid. The pectins occur in the cell wall of higher plants and control at least partly the mechanical properties, the ion exchange properties and the swelling of the cell walls. 

---