Fig. 1

Optimization protocols for bacteriophage elution and extraction. Optimization strategy for phage DNA extraction from soil samples prior metagenomic analysis. An efficient concentration and purification of soil bacteriophages together with a complete removal of bacterial DNA is anticipated. Bacteriophage elution (route 1–6), concentration (route I–III) and DNA extraction (route A–E) methods are evaluated for efficiency using a spiked soil sample (A511, 2638AΔLCR, T7 at 10⁶ PFU/g soil) and plaque assays. Bacterial DNA depletion was assessed using 16S rRNA qPCR. Optimal phage extraction route is highlighted in grey as verified by sequencing metagenomics. LIT literature suggested buffer, SM saline magnesium, AKC amended potassium citrate, PBS phosphate-buffered saline, O/N overnight, PPBS protein supplemented PBS, w/v weight to volume, PES polyether sulfone, TFF tangential flow filtration, CsCl caesium chloride, CTAB cetyltrimethylammonium bromide, NaCl sodium chloride.