Isolation and biological activities of 3-hydroxy-4(1H)-pyridone

摘要

ABSTRACT3-Hydroxy-4(4H)-pyridone (3,4-DHP), a degraded product of mimosine β-N-(3-hydroxy-4-oxypyridyl)-α-aminopropionic acid, is known to cause goiters, loss of hair, and infertility in animals, but limits of 3,4-DHP on separation and purification have prevented efforts on investigating other toxicity and biological properties of 3,4-DHP. By this study, a novel and simple isolation of 3,4-DHP was developed either from Leucaena leaves using an ion-exchanged resin or mimosine degraded in high temperature (110°C, 6 h). The inhibition of mimosine on the growth of barnyardgrass was approximately fourfold higher (IC50 = 0.04 mg g−1) than that of 3,4-DHP (IC50 = 0.15 mg g−1). In general, the antifungal activity of mimosine is much stronger than that of 3,4-DHP, but it differs depending on the kind of fungi. The 1,1-diphyenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of 3,4-DHP, in contrast with the growth inhibitory activity, is about fourfold stronger EC50 = 2.4 mg g−1 gallic acid equivalent (GA...