Table 3. Comparison of mean of zone inhibition between aqueous and ethanol extracts of Aloe vera against the growth of Aspergillus niger at five different concentrations.
| Concentration | Group | Mean±SD | Mean difference (95% CI) |
t-statistic (df) |
p-valuea |
|---|---|---|---|---|---|
| 50.0 g/mL | Aqueous | 16.0±1.4 | -18.8 (-20.3,-17.3) | -28.342 (8) | < 0.001 |
| Alcohol | 34.8±0.4 | ||||
| 25.0 g/mL | Aqueous | 14.0±1.4 | -20.0 (-21.8,-18.2) | -25.820 (8) | < 0.001 |
| Alcohol | 34.0±1.0 | ||||
| 12.5 g/mL | Aqueous | 7.6±0.9 | -13.4 (-15.1,-11.7) | -17.907 (8) | < 0.001 |
| Alcohol | 21.0±1.4 | ||||
| 6.25 g/mL | Aqueous | 6.8±1.1 | -2.80 (-4.3,-1.3) | -4.000 (8) | < 0.001 |
| Alcohol | 9.6±0.9 | ||||
| 3.125 g/mL | Aqueous | 0.0±0.0* | n/a | n/a | n/a |
*t-statistics could not be determined as standard deviations for both groups were 0; aIndependent t-test; CI: confidence interval; n/a: non-applicable. No zone of inhibition seen.