Fig. 1.

Direct PCR protocol universally adapted to living organism-derived samples including plants, animals, bacteria and fungi. A Flow chart presenting the direct PCR technique. B Amplification of constitutive genes (16S, ITS, HGF, NAD) from direct templates without DNA purification, respectively, using bacterial colonies (a), fungal mycelia, environmental samples and food products (b, c), human tissues (d) and plant leaf discs (e). Conventional PCR using purified genomic DNA (DNA) was performed versus direct PCR from crude templates (direct). DNA purified genomic DNA was presented as a positive control, M 1 Kb DNA ladder, NC negative control