Chondroitin degradation products

Mixed digests of hyaluronic acid and chondroitin sulfate (A or C) with testicular hyaluronidase yield, in addition to the degradation products from the parent polysaccharides, products of transglycosylation, consisting of hybrid oligosaccharides and containing repeating units from both polysaccharides (53b),... 

The rather vigorous conditions required for N-deacetylation can cause degradation.272 A recovery of 43% was reported273 for the hydrazinolysis product of chondroitin 4-sulfate, the extent of N-... 

Bollet et al. [11] demonstrated the presence of hyaluronidase activity in various mammalian tissues. They showed that this type of hyaluronidase differed from the testicular type concerning pH optimum and pH range of activity. Subsequent studies revealed that the enzyme was present in the lysosomal fraction of the tissues [12]. The liver is an especially rich source [13]. Degradation of hyaluronan leads to the same end products as testicular hyaluronidase [11]. Lysosomal hyaluronidase from rat liver degrades chondroitin-4- and -6-sulfate, but not dermatan sulfate, desulfated dermatan sulfate, heparan sulfate, keratan sulfate, or heparin [14], Lysosomal hyaluronidase has an acid pH optimum and a narrow pH range of activity [14]. This difference in pH profile of activity has commonly been used to differentiate between testicular and lysosomal hyaluronidase. A similar acid-active hyaluronidase is present in human serum [15]. 

Chondroitin 4-sulfate is easily differentiated from the sulfated polysaccharides of the heparin type by its negative optical rotation, and from dermatan sulfate (also called chondroitin sulfate B or /S-heparin) by the identification of L-iduronic acid in the latter. However, it is difficult to distinguish it from chondroitin 6-sulfate ( chondroitin sulfate C ), since the differences in optical rotation, solubility, and susceptibility to enzymic degradation between the two substances are minimal or non-existent. It is probable that studies made in the past with products isolated from incompletely characterized sources have dealt with mixtures of both chondroitin sulfates. 

A product possessing a constitution similar to those of chondroitin 4- and 6-sulfate, but with a very small content of sulfate, was isolated from cornea and named chondroitin . It is degraded by testicular and bacterial hyal-... 

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