Improvement of ACE inhibitory activity of chitooligosaccharides (COS) by carboxyl modification

In the present research, chitooligosaccharides (COS) were carboxylated with –COCH2CH2COO− groups to obtain specific structural features similar to Captopril®. Angiotensin I converting enzyme (ACE) inhibitory activity of carboxylated COS was studied and observed to enhance its activity with increased substitution degree. Further, Lineweaver–Burk plot analysis revealed that inhibition was competitive via obligatory binding site of the enzyme. This was accompanied with substitution of positively charged quarternized amino groups to COS with different substitution degrees, in which negative impact on ACE inhibition was observed.

COCH2CH2COO− group, which is similar to Captopril® in structure, was introduced to chitooligosaccharides (COS). Angiotensin I converting enzyme (ACE) inhibitory activity of COS was successfully improved by the introduced group. ACE inhibitory mechanism of COS derivative was competitive via obligatory binding site of the enzyme.Figure optionsDownload as PowerPoint slide