• Journal of Apiculture
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• v.34 no.2
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• pp.125-129
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• 2019

Honey bees are important pollinators in agriculture, but are threatened by the pathogen Ascosphaera apis, which causes chalkbrood. Despite attempts to control this fungus using synthetic fungicides, none of them have been proven to be completely effective. Among 640 natural compounds that we tested, 4-hydroxyderricin (MIC=3.125, 6.25 mg/L after 24 h and 48 h growth, respectively) exhibited the strongest anti- Ascosphaera apis activity, followed by acetylshikonin (MIC=12.5 mg/L for 24 h and 48 h growth). 4-Hydroxyderricin showed selective growth inhibition of Ascosphaera apis and Rhizopus oryzae among tested fungus strains. Treatment 4-hydroxyderricin with miconazole revealed a synergistic effect (FICI=0.65±0.13 at 48 h incubation). These findings suggest that 4-hydroxyderricin, which has antifungal activity against Ascosphaera apis but few other fungal species, can effectively control infectious fungal diseases. Combined treatment of bees with 4-hydroxyderricin and miconazole could reduce cytotoxicity and improve the cost effectiveness of treatment.

• Biomolecules & Therapeutics
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• v.21 no.3
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• pp.234-240
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• 2013

Monoamine oxidase inhibitors (MAOI) have been widely used as antidepressants. Recently, there has been renewed interest in MAO inhibitors. The activity-guided fractionation of extracts from Angelica keiskei Koidzumi (A. keiskei K.) led to the isolation of two prenylated chalcones, xanthoangelol and 4-hydroxyderricin and a flavonoid, cynaroside. These three isolated compounds are the major active ingredients of A. keiskei K. to inhibit the MAOs and DBH activities. Xanthoangelol is a nonselective MAO inhibitor, and a potent dopamine ${\beta}$-hydroxylase (DBH) inhibitor. $IC_{50}$ values of xanthoangelol to MAO-A and MAO-B were calculated to be 43.4 ${\mu}M$, and 43.9 ${\mu}M$. These values were very similar to iproniazid, which is a nonselective MAO inhibitor used as a drug against depression. The $IC_{50}$ values of iproniazid were 37 ${\mu}M$, and 42.5 ${\mu}M$ in our parallel examination. Moreover, $IC_{50}$ value of xanthoangelol to DBH was calculated 0.52 ${\mu}M$. 4-Hydroxyderricin is a potent selective MAO-B inhibitor and also mildly inhibits DBH activity. The $IC_{50}$ value of 4-hydroxyderricin to MAO-B was calculated to be 3.43 ${\mu}M$ and this value was higher than that of deprenyl (0.046 ${\mu}M$) used as a positive control for selective MAO-B inhibitor in our test. Cynaroside is a most potent DBH inhibitor. The $IC_{50}$ value of cynaroside to DBH was calculated at 0.0410 ${\mu}M$. Results of this study suggest that the two prenylated chalcones, xanthoangelol and 4-hydroxyderricin isolated from A. keiskei K., are expected for potent candidates for development of combined antidepressant drug. A. keiskei K. will be an excellent new bio-functional food material that has the combined antidepressant effect.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2815-2818
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• 2013