Main Article Content
COX-1 and COX-2 inhibitory activity in extracts prepared from <em>Eucomis</em> species, with further reference to extracts from <em>E. autumnalis autumnalis</em>
Abstract
Prostaglandins are important mediators of the body’s response to pain
and inflammation, and are formed from essential fatty acids found in cell membranes.
This reaction is catalysed by cyclooxygenase, a membrane-associated enzyme
occurring in two isoforms, COX-1 and COX-2. Non-steroidal anti-inflammatory
drugs (NSAIDs) act by inhibiting the activity of COX. The investigation of
Eucomis species (a popular South African medicinal plant) for potential anti-inflammatory
activity showed high levels of COX-1 and -2 inhibitory activity associated
with several species, specifically E. autumnalis and E. humilis. Further investigation
was conducted using E. autumnalis subspecies autumnalis, as this is the species
that is most widely utilised by traditional healers in southern Africa. The
bulb extracts from this species were characterised by higher IC50 values for
both COX-1 and COX-2 inhibition than obtained for the leaf and root extracts.
The ratio of COX-2/COX-1 inhibitory activity was, however, similar to that
of the root extracts, both values being less than one. The leaf extracts showed
higher COX-1 than COX-2 inhibitory activity, with a ratio of 1.9. Most traditional
remedies utilising Eucomis, are prepared from the bulbs (possibly including
some root material) of this species.
South African Journal of Botany 2002, 68: 80–85
and inflammation, and are formed from essential fatty acids found in cell membranes.
This reaction is catalysed by cyclooxygenase, a membrane-associated enzyme
occurring in two isoforms, COX-1 and COX-2. Non-steroidal anti-inflammatory
drugs (NSAIDs) act by inhibiting the activity of COX. The investigation of
Eucomis species (a popular South African medicinal plant) for potential anti-inflammatory
activity showed high levels of COX-1 and -2 inhibitory activity associated
with several species, specifically E. autumnalis and E. humilis. Further investigation
was conducted using E. autumnalis subspecies autumnalis, as this is the species
that is most widely utilised by traditional healers in southern Africa. The
bulb extracts from this species were characterised by higher IC50 values for
both COX-1 and COX-2 inhibition than obtained for the leaf and root extracts.
The ratio of COX-2/COX-1 inhibitory activity was, however, similar to that
of the root extracts, both values being less than one. The leaf extracts showed
higher COX-1 than COX-2 inhibitory activity, with a ratio of 1.9. Most traditional
remedies utilising Eucomis, are prepared from the bulbs (possibly including
some root material) of this species.
South African Journal of Botany 2002, 68: 80–85
