Table 3. Assessment of yield of metagenomic DNA obtained by methods M1 to M6 for different soils.
| Yield (μg/g of soil) | ||||
|---|---|---|---|---|
| Methods | Garden soil | Sewage sludge | Lake soil | Compost |
| M1 | 1.34 ± 0.01**** | 1.49 ± 0.02**** | 1.42 ± 0.02*** | 0.93 ± 0.03**** |
| M2 | 4.92 ± 0.03** | 5.01 ± 0.04*** | 1.52 ± 0.04*** | 2.24 ± 0.07**** |
| M3 | 3.63 ± 0.06*** | 0.56 ± 0.05**** | 1.08 ± 0.02*** | 0.62 ± 0.03**** |
| M4 | 5.06 ± 0.05* | 2.06 ± 0.06**** | 2.25 ± 0.04**** | 4.15 ± 0.06*** |
| M5 | 2.01 ± 0.03*** | 2.56 ± 0.05**** | 4.58 ± 0.02*** | 4.89 ± 0.03 ns |
| M6 | 5.48 ± 0.03 | 7.81 ± 0.04 | 5.19 ± 0.06 | 4.98 ± 0.04 |
DNA concentration (μg/mL) was quantified in a spectrophotometer (A260 nm).
Yield in μg per gram of soil = concentration of DNA (μg/μL). Volume used to suspend DNA (μL) /weight of soil (g)
P values were generated by Graph Pad Prism 5.0 software using paired T-test analysis.
P value < 0.05 is considered to be statistically significant. DNA extraction methods performing worse at a statistically significant level as compared with the best performing method M6 are indicated by asterisks
**** indicates P < 0.0001
*** indicates P < 0.001
** indicates P < 0.01
* indicates P < 0.05
ns indicates P > 0.05 which is statistically non-significant.