Degraded and undegraded carrageenans and antipeptic activity

Abstract

Abstract The antipeptic activities of a series of undegraded κ- and Λ-carrageenans and degraded carrageenans have been examined by two methods. The activities differ quantitatively. Compared with the κ-carrageenans, the Λ-carrageenans, as a group, have greater activity and this is associated with low 3,6-anhydro-d-galactose and high ester sulphate content. Within the series of undegraded carrageenans, both κ and Λ, differences in antipeptic activity are significantly and positively related to differences in sulphate content. In addition to the effect of sulphate, 3,6-anhydrogalactose content appears to be inversely related to activity but in the Λ-series only; differences in viscosity are without effect. Initial degradation without loss of sulphate resulted in loss of activity but further degradation, also without loss of sulphate did not reduce activity further. Antipeptic activity appears to depend on a combination of structural features of which the differences between κ-Λ carrageenans, molecular size and polyanionic properties are aspects.