Fig. 4

Comparison of DNA extraction kits and their extraction biases evaluated using 16S rRNA amplicon sequencing. Sequencing data were analysed with Deblur through QIIME2. Samples analysed are the actual (ground truth) with and without adjustment for 16S rRNA copy number, the NIBSC DNA-Gut-Mix RR, and DNA extracted from the WC-Gut RR using Kit1, Kit2, Kit3, Kit4, Kit5, Kit6, Kit7, and Kit8, based on the average of five replicates. A Values of each sample using the four-measure reporting system consisting of Sensitivity, False-Positive Relative Abundance (FPRA), Diversity, Similarity to Actual composition, and Similarity to the NIBSC DNA-Gut-Mix RR. B Relative abundance of (%) each genera in each sample. C β-diversity analysis using Bray-Curtis dissimilarity measure visualised by a principal coordinate analysis. D Relative abundance (%) of gram-positive and gram-negative bacteria recovered using each kit