density gradient centrifugation resulted in the partial separation of the extracted proteoglycans into two types with different densities : a heparan sulfate proteoglycan that was enriched in the heavier fraction ( p greater than 1.43 g/ml ) , and a chondroitin sulfate proteoglycan that was concentrated in the lighter fractions ( p less than 1.41 ) .
C0033692
proteoglycans
C0033689
chondroitin sulfate proteoglycan