Monoamine oxidase inhibitors from rhizoma of Coptis chinensis
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Planta Medica
|March 29, 2001
Abstract:
Three protoberberine alkaloids jatrorrhizine, berberine and palmatine were isolated from the monoamine oxidase (MAO) inhibitory fraction of the methanol extract of Coptis chinensis rhizoma. Jatrorrhizine was shown to inhibit non-competitively both MAO-A and -B from rat brain mitochondria with the IC50 values of 4 and 62 microM, respectively. Berberine only competitively inhibited MAO-A with an IC50 values of 126 microM whereas palmatine exhibited, up to 200 microM, no inhibition on any type of the enzyme. The structure-activity relationship was briefly discussed.
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