Table 2. Effects of sample matrices on direct qPCR.

C. muytjensii live cells/PCR (cfu/PCR tube)	Physiological saline (Ct)	Direct qPCR components
		No heat (Ct)		Heat following PCR thermal cycling (Ct)
		Pellet†	Supernatant‡	Pellet†	Supernatant‡
2.5 × 106	14.5 ± 0.49*	15.0 ± 0.65	14.9 ± 0.58	14.7 ± 0.64	14.6 ± 0.66
2.5 × 105	17.3 ± 0.71	16.3 ± 0.41	16.4 ± 0.43	16.8 ± 0.63	16.7 ± 0.58
2.5 × 104	20.9 ± 0.31	20.6 ± 0.47	20.5 ± 0.42	20.5 ± 0.58	20.3 ± 0.51
2.5 × 103	23.8 ± 1.13	24.0 ± 0.72	24.2 ± 0.71	24.2 ± 0.75	24.0 ± 0.63

^*Direct qPCR measurements were performed in duplicate. The Ct values are presented as the means ± SD (n = 2).

^†The pellet was obtained through the centrifugation of the direct qPCR master mix with or without PCR thermal cycling. The freshly prepared direct qPCR master mix was added to the pellet to generate the matrices of labelled Pellet. These matrices were used to suspend C. muytjensii.

^‡The supernatant was obtained through the centrifugation of direct qPCR master mix with or without PCR thermal cycling. These supernatants were used as the matrices labelled Supernatant to suspend C. muytjensii.