Investigation of plants used in Jamaican folk medicine for anti-bacterial activity

We have started a systematic scientific study of folklore medicinal plants currently used as alternative medicine in Jamaican society. In this initial study, extracts of plants widely used by the islanders are studied for antibacterial activity against five common pathogens; Streptococcus group A, Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa and Escherichia coli. These studies revealed that 25 percent (approximately) of the plant extracts had antimicrobial activity against at least one of the microbes used. Subsequent to these observations, extracts from Mikania micrantha were examined in detail. This led to the isolation of two sesquiterpenoids, mikanolide and dihydromikanolide, with activity against S. aureus and C. albicans. The results suggest that traditional folk medicine could be used as a guide in our continuing search for new natural products with potential medicinal properties.(Au)

Extraction of an hyperglycaemic principle from the annatto (Bixa orellana)

The red powdery extract from the seeds of the annatto, Bixa orellana, is a well known food colouring. In an oil suspension it is used as a folk remedy (bush tea) in the West Indies, for diabetes mellitus. Detailed investigations on this extract, yielded a methyl ester, trans-bixin, molecular weight 394 and molecular formula C24 H30 O4. This purified substance was demonstrated, in anaaesthetised mongrel dogs, to cause hyperglycaemia. Concomitant electron microscopy of tissues biopsies, revealed damage to mitochrondria and endoplasmic reticulum mainly in liver and pancreas. When dogs were fed on a diet fortified with riboflavin, there was neither demonstratable tissue damage nor associated hyperglycaemia. These findings point to: (i) the potential dangers of informal medications such as 'bush teas'; (ii) the possible role of plant extracts/food additives in the development of diabetes mellitus especially in the undernourished state. (AU)

Isolation, purification and identification of the hyperglycaemic principle of the annatto (Bixa orellana) - abstract

The crude extract eluted from the seed of Bixa orellana was seen to cause hyperglycaemia in anaesthetized dogs. Further investigation was carried out to find the biologically active component. Column chromatography, PLC and recrystallizations yielded a pure residue with m.p. 220. The experimental dogs in quantities below one gram, it caused sustained hyperglycaemia and severe damage to tissues of the liver, kidney and pancreas. The level of toxicity associated with this plant is of interest, since its extract is widley used in various goods (AU)

Toxicity of the hyperglycaemic-inducing extract of the Annatto (Bixa orellana) in the dog

The Annatto seed coat extract, which is commonly used in folklore in treating diabetes mellitus, has been investigated for its effects on blood sugar levels in the dog. An alkali-soluble hyperglycaemia-inducing fraction was detected, and detailed studies revealed toxic effects in the pancreas and liver accompanied by hyperglycaemia and apparent tendency to increased insulin levels. The toxicity was diminished by feeding riboflavin. The relevance of this finding points to a possible aetiological role in the development of malnutrition-related diabetes mellitus and also to the potential toxicity inherent in the widespread use of folklore medicines (AU)

Preliminary investigations of the wound-healing properties of a Jamaican folk medicinal plant (justicia pectoralis)

Coumarin was found to be the major component of an acetone extract of the herbaceous plant, justicia pectorials, which is used in folk medicine for the treatment of cuts. Fresh wounds created on Wistar rats and treated with the extracted coumarin, showed attenuated inflammatory process and significantly enhanced wound healing compared with control rats. The use of this plant therefore appears to influence the wound-healing process (AU)