Table 2.

Arcobacter species detected according to the method at the 5 sampling points in the wastewater treatment plant on the 6 different sampling occasions^a.

Species detected		m-PCR		Culturing method
		Direct	Postenrichment	Direct	Postenrichment
A. butzleri (Ab)		19 (100)	15 (100)	22 (78.6)	24 (82.8)
A. cryaerophilus (Ac)		10 (52.6)	9 (60)	27 (96.4)	16 (55.2)
A. defluvii (Ad)		0	0	2 (7.1)	3 (10.3)
A. nitrofigilis (Anit)		0	0	1 (3.6)	0
A. cloacae (Aclo)		0	0	0	2 (6.9)
A. skirrowii (As)		0	0	1 (3.6)	2 (6.9)
A. thereius (At)		0	0	3 (10.7)	4 (13.8)
A. ellisii (Ae)		0	0	2 (7.1)	0
Sampling month	Sampling point	m-PCR		Culturing method
		Direct	Postenrichment	Direct	Postenrichment
April 2009	Influent water	Ac+Ab	ND	Ac+Anit	Ac+Ad+Aclo
	Primary sedimentation tank	Ac+Ab	ND	Ac+Ab+Ad	Ac+Ab
	Secondary bioreactor tank	Negative	ND	Ac+Ad	Ac+Ad
	Secondary sedimentation tank	Negative	ND	Negative	Ab+Ad
	Effluent water	Negative	ND	Negative	Negative
June 2009	Influent water	Negative	ND	Ac+Ab	Ab
	Primary sedimentation tank	Ab	ND	Ac+Ab	Ab
	Secondary bioreactor tank	Negative	ND	Ac+Ab	Ab
	Secondary sedimentation tank	Negative	ND	Ac	Ac+Ab
	Effluent water	Negative	ND	Ac+Ab	Ab
October 2009	Influent water	Ac+Ab	ND	Ac	Ac+Ab
	Primary sedimentation tank	Ac+Ab	ND	Ac+Ab	Ac+Ab
	Secondary bioreactor tank	Negative	ND	Ac	Ab
	Secondary sedimentation tank	Ab	ND	Ac+Ab	Ac+Ab
	Effluent water	Negative	ND	Ac+Ab	Ab
May 2011	Influent water	Ab	Ab+Ac	Ac+At	Ab+Ac+At
	Primary sedimentation tank	Ab+Ac	Ab+Ac	Ab+Ac+At	Ac+At
	Secondary bioreactor tank	Ab	Ab+Ac	Ab+Ac+As	Ac+As
	Secondary sedimentation tank	Ab	Ab+Ac	Ab+Ac	Ab+Ac
	Effluent water	Ab	Ab+Ac	Ab+Ac	Ab+Ac
June 2011	Influent water	Ab+Ac	Ab	Ab+Ac+Ae	Ab+As
	Primary sedimentation tank	Ab+Ac	Ab	Ab+Ac	Ab+Ac
	Secondary bioreactor tank	Ab	Ab	Ab+Ac+At	At
	Secondary sedimentation tank	Ab	Ab	Ab+Ac	Ab+Ac+At
	Effluent water	Ab	Ab	Ab+Ac	Ab
September 2011	Influent water	Ab+Ac	Ab+Ac	Ab+Ac+Ae	Ab+Aclo
	Primary sedimentation tank	Ab+Ac	Ab+Ac	Ab+Ac	Ab
	Secondary bioreactor tank	Ab+Ac	Ab+Ac	Ab+Ac	Ab+Ac
	Secondary sedimentation tank	Negative	Ab	Ab	Ab
	Effluent water	Negative	Ab+Ac	Ab+Ac	Ab+Ac
Total No. positive samples (%)		19/30 (63.3)	15/15 (100)	28/30 (86.7)	29/30 (86.7)

^aThe identified species are only mentioned once, independently of the number of strains obtained from each specific sample.

m-PCR: multiplex PCR Houf et al., 2000 [19]

ND: not done.