Fig. 7

Effects of alkaloid extracts from C. zeyheri on drug accumulation in mycobacteria. Cells were loaded with ciprofloxacin and incubated for an hour. Cells were centrifuged, supernatant removed and exposed to the various compounds in buffer with glucose. One sample was exposed to the buffer alone with no glucose being added and this was the control. Cells were then centrifuged again and lysed with glycine-HCl. Cell debris was collected by centrifugation and the amount of ciprofloxacin in the supernatant quantified at excitation and emission wavelengths of 270 nm and 452 nm respectively using an RF1501 Shimadzu spectrofluorimeter. Values are the mean of ± SD for n = 2 for duplicate determinations **P < 0.01 in comparison with the cells exposed to glucose only