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Merwilla natalensis bulbs were cultivated at two different sites under different treatments. Bulbs were harvested every six months for a period of two years and were tested for antibacterial, anti-inflammatory and anthelmintic activity. The cultivation treatments had no significant effect (P ≤ 0.05) on neither the antibacterial activity, nor the anti-inflammatory activity. However, the age of the bulbs had a significant effect against the test bacteria and on the inhibition of prostaglandin synthesis by COX-1, with activity decreasing as the bulbs matured. The cultivation treatments had a significant effect on the antihelmintic activity of bulbs cultivated at the Fort Hare site. Results suggest that irrigation might increase the antihelmintic activity of the bulbs if cultivated in areas of low rainfall. The age of the bulbs at both sites had a significant effect on the antihelmintic activity, with activity increasing with plant maturity.

Seven traditional remedies used in South Africa for bacterial infections were prepared according to the traditional method of preparation. The remedies consisted of 1–3 plants of the following species: Acorus calamus , Artemisia afra , Alepidea amatymbica , Jatropha zeyheri , Pentanisia prunelloides , Tetradenia riparia and Warburgia salutaris and were prepared as decoctions or infusions. The aqueous extracts were partitioned onto ethyl acetate. The aqueous extracts and the ethyl acetate phases were tested for antibacterial activity in the microtitre plate assay. The aqueous extracts had no detectable activity, whereas several of the ethyl acetate phases had some activity. When relating this activity to the daily dose of the remedies it becomes questionable whether the remedies have any antibacterial effect.

Levels of anti-inflammatory activity exhibited by Eucomis autumnalis autumnalis were affected by the environmental conditions during the period of winter dormancy. Bulbs stored at low temperatures (10 °C) showed a limited period of time during which the anti-inflammatory activity of the bulb extracts was higher than that of the control. This effect was evident for a longer period in the leaves. Extracts prepared from E . autumnalis (subspecies autumnalis ) bulbs, which were removed from the soil and stored at 8-10 °C during the winter months, exhibited significantly higher COX-1 inhibitory activity than those extracts prepared from control bulbs maintained in the soil in a greenhouse (15-24 °C) during winter, and from bulbs stored dry in paper bags (± 18 °C). A second harvest, performed on plants that had been returned to the soil after winter storage, was conducted half-way through the growing season. Higher COX-1 inhibitory activity was observed in the leaf extracts from the plants subjected to cold storage, than in the extracts from plants stored dry or in the greenhouse. No significant difference was observed at this stage between the activity of the bulb and root extracts from the different treatments. All extracts were prepared at a concentration of 250μg ml - 1 for comparison.