Fatty Acids with in Vitro Binding Affinity for Human Opioid Receptors from the Fungus Emericella nidulans

摘要

Bioassay-guided fractionation of the EtOAc extracts of the epiphytic fungus Emericella nidulans resulted in the isolation of a mixture of two fatty acids This mixture showed 98% binding affinity to human 5 opioid receptor. These two fatty acids weie identified as palmitic (PAM), 1, and linolcic acids (LNA), 2, by 1D NMR as well as by GC/MS analysis, after their methylation We found that different ratio mixtures of I and 2 showed variations in selective binding activities to human 8 opioid receptors Five more fatty acids, arachidonic acid (ARA), 3, cis-4,7,10,13,16,19-docosahexanoic acid (DHA), 4, cis-5,8,11,14,17-eicosapcntaenoic acid (EPA), 5, hnolenic acid (ALA), 6, and γ-hnolenic acid (GLA), 7, were evaluated for their binding affinity for opioid receptors. ARA, 3, displayed affinity to δ and μ human opioid receptors with 68% and 80%, respectively. GLA, 7, showed selective binding affinity to μ leceptor with a value of 55%. These findings provide fascinating insight into the use of foods with high concentrations of fatty acids.