One therapeutic approach for preventing diabetes mellitus and obesity is to 
retard the absorption of glucose via inhibition of α-glucosidase. Two 
unsaturated fatty acids with strong α-glucosidase inhibitory activity, 
7(Z)-octadecenoic acid (1) and 7(Z),10(Z)-octadecadienoic acid (2), were 
purified from the body wall of Stichopus japonicus. IC(50) values of compounds 1 
and 2 were 0.51 and 0.67 μg/mL against Saccharomyces cerevisiae α-glucosidase 
and 0.49 and 0.60 μg/mL against Bacillus stearothermophilus α-glucosidase, 
respectively. These compounds mildly inhibited rat-intestinal sucrase and 
maltase. In addition, both compounds showed a mixed type of inhibition against 
S. cerevisiae α-glucosidase and were very stable under thermal and acidic 
conditions up to 60 min. The K(I) and K(IS) values of compounds 1 and 2 were 
0.44 and 0.22 μg/mL, and 0.39 and 0.13 μg/mL, respectively.
PRACTICAL APPLICATION: One therapeutic approach for preventing diabetes mellitus 
is to retard the absorption of glucose via inhibition of α-glucosidase. In this 
study, 2 fatty acids with strong α-glucosidase-inhibitory activity, 
7(Z)-octadecenoic acid and 7(Z),10(Z)-octadecadienoic acid, were purified and 
identified from sea cucumber. Therefore, sea cucumber fatty acids can 
potentially be developed as a novel natural nutraceutical for the management of 
type-2 diabetes.