Search

Plants belonging to the Amaryllidaceae contain an exclusive group of alkaloids, known as sources of important biological activities. In the present work, Pancratium illyricumL., a species belonging to this family and endemic of Sardinia (Italy), was investigated for its alkaloid content. Fresh bulbs and leaves were processed separately. Standard extraction and purification procedures were applied to obtain fractions and compounds for GC–MS and NMR analysis. In addition to eight already known alkaloids (1–8), 11α-hydroxy-O-methylleucotamine (9) was isolated for the first time and its structure completely determined by one and two-dimensional 1H and 13C NMR spectroscopy. This new galanthamine-type compound exhibited a pronounced in vitro acetylcholinesterase (AChE) inhibitory activity (IC50 = 3.5 ± 1.1 μM) in comparison to the reference standard galanthamine hydrobromide (IC50 = 1.5±0.2 μM).

3,5-O-dicaffeoyl-4-O-malonilquinic acid (1) (irbic acid) has been isolated for the first time from cell cultures of Centella asiatica and till now it has never been reported to be present in the intact plant. Evidence of its structure was obtained by spectroscopic analyses (MS/NMR). Besides 1, cell cultures produce also the known 3,5-O-dicaffeoylquinic acid, chlorogenic acid, and the triferulic acid 2 (4-O-8′/4′-O-8″-didehydrotriferulic acid). Biological activities were evaluated for compound 1, which showed to have a strong radical scavenging capacity, together with a high inhibitory activity on collagenase. This suggests a possible utilization of this substance as a topical agent to reduce the skin ageing process.