Crinane alkaloids of the amaryllidaceae with cytotoxic effects in human cervical adenocarcinoma (HeLa) cells.

The family Amaryllidaceae has a long history of usage in the traditional medicinal practices of the indigenous peoples of South Africa, with three of its species known to be used for cancer treatment. Furthermore, the Amaryllidaceae is widely recognized for its unique alkaloid constituents, several of which exhibit potent and selective cytotoxic activities. In this study, several crinane alkaloids derived from local Amaryllidaceae species were examined for cytotoxic effects against the human cervical adenocarcinoma cell line, of which distichamine was the most potent (IC50 2.2 microM).

Antibacterial activity of crinane alkaloids from Boophone disticha (Amaryllidaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Boophone disticha (Amaryllidaceae) is one of the most common bulbous plants used for medicinal purposes by the indigenous people of southern Africa. Its use as a narcotic substance by the Khoi/San tribes has been known for several centuries, while the Sotho, Xhosa and Zulu people are known to use the plant to treat a host of ailments, including inflammation, wounds, gynaecological conditions and psychosis. AIM OF THE STUDY: Much of the pharmacological work on the plant, such as affinity to the serotonin transporter, has been based on its reputed usage for narcotic purposes. However, its widespread use to treat wounds and infections has not been linked to a specific chemical entity. In this regard, Boophone disticha was here examined for its phytochemical composition which could shed light on the use of the plant for such purposes. MATERIALS AND METHODS: The known crinane alkaloids buphanidrine and distichamine were isolated via column chromatography of the ethanolic extract of bulbs of Boophone disticha. Structural details of the compounds were determined by high field 2D NMR and mass spectroscopic techniques. Microbial activity against selected Gram-positive and Gram-negative bacteria was ascertained according to the micro-dilution assay. RESULTS: Both buphanidrine and distichamine were uncovered as novel, broad spectrum moderately active, antibacterial agents with the best MIC value detected at 0.063mg/ml for Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. MIC values for Bacillus subtilis were two-fold less than that observed for the other three bacteria, suggesting that the extract and pure compounds were selective in their interaction with the bacterial pathogens. CONCLUSION: Phytochemical investigation of Boophone disticha has led to the identification of two known crinanes, buphanidrine and distichamine. Based on the reputed traditional use of the plant for wounds and infections, both compounds were screened for antibacterial activity which revealed them to be novel, broad spectrum antibacterial agents with the best MIC value set at 0.063mg/ml. Their close structural similarity may have bearing on their similar activity profiles.