title: Isolation of isoflavones inhibiting DOPA decarboxylase from fungi and streptomyces.
abstract: By screening of culture filtrates of fungi and streptomyces for activity in inhibit dopa decarboxylase the following isoflavone compounds were obtained: psi-tectorigenen (I), genistein (II), orobol (IV), 8-hydroxygenistein (V) and a new compound (III). III was elucidated to be 3', 4', 5, 7-tetrahydroxy-8methoxy isoflavone. Among these isoflavones, IV and III showed the strongest activity in inhibiting dopa decarboxylase. All these isoflavones also inhibited histidine decarboxylase and catechol-O-methyltrasnferase. Activities of these compounds to inhibit tyrosine hydroxylase and dopamine beta-hydroxylase were examined. Orobol which showed no or only slight inhibition of tyrosine hydroxylase and dopamine beta-hydroxylase exhibited a significant hypotensive effect on spontaneously hypertensive rats.
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents; D065105:Aromatic Amino Acid Decarboxylase Inhibitors; D001230:Aspergillus / Q000032:analysis*; D001234:Aspergillus niger / Q000032:analysis*; D005419:Flavonoids / Q000302:isolation & purification*; D006640:Histidine Decarboxylase / Q000037:antagonists & inhibitors; D007529:Isoflavones / Q000302:isolation & purification* / Q000494:pharmacology; D008750:Methyldopa / Q000494:pharmacology; D051379:Mice; D051381:Rats; D013302:Streptomyces / Q000032:analysis*
chemical_list: D000959:Antihypertensive Agents; D065105:Aromatic Amino Acid Decarboxylase Inhibitors; D005419:Flavonoids; D007529:Isoflavones; D008750:Methyldopa; D006640:Histidine Decarboxylase