Table 3.
Antimicrobial activity of methanol leaf extract (KAL) and stem bark extract (KASB) of K. africana and leaf extract (SHL) and root extract (SHR) of S. hispidus by agar diffusion method. Mean zones of growth inhibition (plus diameter of well) are mean (mm) of 3 independent experiments, mean ± SD, n = 3 replicates, diameter of well/cup = 8 mm, reference antimicrobial agents: CPC: chloramphenicol (1 mg/mL), CTZ: clotrimazole (1 mg/mL), nd: not determined.
| Mean zones of growth inhibition (mm) | |||||
|---|---|---|---|---|---|
| Extract (mg/mL) | Test organisms | ||||
|
S. aureus
ATCC 25923 |
B. subtilis
NCTC 10073 |
E. coli
ATCC 25922 |
P. aeruginosa
ATCC 27853 |
C. albicans | |
| KAL | |||||
| 10 | 12.45 ± 0.50 | 12.50 ± 0.40 | 12.00 ± 0.50 | 0.0 | 15.50 ± 0.50 |
| 20 | 14.50 ± 0.50 | 13.53 ± 0.50 | 15.50 ± 0.25 | 12.50 ± 0.70 | 18.50 ± 0.55 |
| 50 | 16.35 ± 0.45 | 16.50 ± 0.35 | 19.65 ± 0.55 | 15.50 ± 0.70 | 23.35 ± 0.45 |
| KASB | |||||
| 10 | 0.0 | 11.50 ± 0.25 | 12.50 ± 0.50 | 0.0 | 12.55 ± 0.55 |
| 20 | 13.00 ± 0.50 | 13.50 ± 0.45 | 16.55 ± 0.25 | 10.50 ± 0.50 | 15.50 ± 0.50 |
| 50 | 15.00 ± 0.55 | 15.00 ± 0.50 | 19.65 ± 0.25 | 14.50 ± 0.25 | 18.5 ± 0.25 |
| SHL | |||||
| 10 | 11.00 ± 0.50 | 0.0 | 11.00 ± 0.50 | 0.0 | 12.50 ± 0.25 |
| 20 | 13.50 ± 0.55 | 12.50 ± 0.50 | 13.25 ± 0.50 | 14.50 ± 0.25 | 14.25 ± 0.25 |
| 50 | 16.55 ± 0.25 | 14.50 ± 0.25 | 17.50 ± 0.25 | 16.55 ± 0.50 | 18.25 ± 0.50 |
| SHR | |||||
| 10 | 12.5 ± 0.50 | 12.55 ± 0.50 | 11.25 ± 0.50 | 0.0 | 12.50 ± 0.20 |
| 20 | 14.50 ± 0.50 | 15.50 ± 0.50 | 15.55 ± 0.50 | 13.00 ± 0.50 | 14.50 ± 0.50 |
| 50 | 18.25 ± 0.25 | 17.50 ± 0.25 | 17.00 ± 0.25 | 15.50 ± 0.25 | 16.50 ± 0.25 |
| CPC | 25.5 ± 0.25 | 31.50 ± 0.25 | 30.55 ± 0.25 | 17.50 ± 0.25 | nd |
| CTZ | nd | nd | nd | nd | 25.50 ± 0.50 |