The Genus Galanthus: A Source of Bioactive Compounds

Abstract

The Amaryllidaceae family is one of the 20 most important alkaloid-containing plant families (Zhong, 2005). It comprises about 1100 perennial bulbous species classified in 85 genera, distributed throughout the tropics and warm temperate regions of the world (Willis, 1988). The specific alkaloids produced by the amaryllidaceous plants have attracted considerable attention due to their interesting pharmacological activities. One of them, galanthamine, is a long acting, selective, reversible and competitive inhibitor of the acetylcholinesterase enzyme (Thomsen et al., 1998), which is marketed as a hydrobromide salt under the name of Razadyne® (formerly Reminyl®) and Nivalin® for the treatment of Alzheimer’s disease, poliomyelitis and other neurological diseases (Heinrich and Teoh, 2004). After its discovery in Galanthus woronowii by Proskurina and co-authors in 1955 (Proskurina et al., 1955), the pharmacological properties of galanthamine soon attracted the attention of the pharmaceutical industry. It was first produced by Sopharma (Bulgaria) under the name of Nivalin® from G. nivalis in the early 1960s, but due to the small plant size and variability of galanthamine content, this species was soon replaced by other plant sources (Berkov et al., 2009b). The genus Galanthus (Snowdrop; Greek gála "milk", ánthos "flower") comprises about 19 species (World Checklist of Selected Plant Families), and to our knowledge 11 have been investigated for their alkaloid content. Although the genus has only been partially studied, phytochemical work has revealed an exceptional diversity of alkaloid structures, many of them reported for the first time and with still unknown bioactivity. The present article provides a brief overview of the phytochemical studies within the genus Galanthus.