Moira Middleton

Biological activity of serotonin conjugates from the seeds of Centaurea nigra

Two serotonin conjugates, N-(trans-p-coumaroyl)-serotonin (1) and N-(trans-feruloyl)-serotonin (maoschamine, 2), isolated from the methanol extract of the seeds of Centaurea nigra, have been assessed for antibacterial and free radical scavenging activities. The general toxicity of 1 and 2 has also been determined by the brine shrimp lethality bioassay.

Antibacterial and free radical scavenging activity of the seeds of Agrimonia eupatoria.

n-Hexane, dichloromethane and methanol extracts of the seeds of Agrimonia eupatoria have been assessed for antibacterial and free radical scavenging activity.

Swarnalin and cis -swarnalin, two new tetrahydrofuran derivatives with free radical scavenging activity, from the aerial parts of Cuscuta reflexa

The reversed-phase HPLC analysis of a methanol extract of the aerial parts of Cuscuta reflexa afforded a non-separable mixture (55 : 45) of two novel tetrahydrofuran derivatives, named swarnalin (1) and cis-swarnalin (2), and a known coumarin, 5,6,7-trimethoxycoumarin (3). The structures of the compounds were elucidated unequivocally by UV, HRFABMS and a series of 1D and 2D NMR analyses. The mixture of 1 and 2 showed significant free radical scavenging activity in the DPPH assay and the RC50 value was found to be 3.80 × 10−4 mg mL−1 for the mixture, compared to 2.88 × 10−5 mg mL−1 for the positive control, quercetin.