TABLE 2.

Summary of chemical characteristics of shale rock (SR), bacteria-inhabited shale rock (BISR), bacterial culture (SR-BC), and sterile control (SR-SC).

Analysis	Field samples		Laboratory studies
	SR	BISR	SR-BC	SR-SC
		Sedimentary porphyrins – monitoring of specific ion
SIM	VO(MTPP), VO(OEP), Ni(OEP)	VO(MTPP), VO(OEP), Ni(OEP), VO(DPP), Ni(TEP), VO(TEP), NiP, VOP	-	VO(MTPP), VO(OEP), Ni(OEP)
		Organic compounds containing porphyrin ring – detection of specific absorption maxima UV-VIS
Soret band	380, 401	420	-	380, 401
Q band	516/549, 529/571	538/576	-	516/549, 529/571
		Organic compounds containing pyrrole ring – detection of specific ion
3 pyrrole rings (m/z: 201)	-	3-[2-[[3-(2-Carboxyethyl)-5-[(3.4-dimethyl-5-oxopyrrol-2-ylidene)methyl]-4-methyl-1H-pyrrol-2-yl]methylidene]-4-methyl-5-oxopyrrol-3-yl]propanoic acid 3-[(5Z)-5-[[4-Ethenyl-5-[(Z)-(4-ethenyl-3-methyl-5-oxopyrrol-2-ylidene)methyl]-3-methyl-1H-pyrrol-2-yl]methylidene]-4-methyl-2-oxopyrrol-3-yl]propanoate	3-[(5Z)-5-[[4-Ethenyl-5-[(Z)-(4-ethenyl-3-methyl-5-oxopyrrol-2-ylidene)methyl]-3-methyl-1H-pyrrol-2-yl]methylidene]-4-methyl-2-oxopyrrol-3-yl]propanoate	-
2 pyrrole rings (m/z: 134)	-	3,3′-Bipyrrole, 2,2′-Bipyrrole, 1,1′-Bipyrrole-2,2′,5,5′-tetraone	3,3′-Bipyrrole, 2,2′-Bipyrrole, 3,3′,4,4′-Tetramethyl-1H,1′H-2,2′-bipyrrole-5,5′-dicarboxylic acid	-
1 pyrrole ring (m/z: 67)	-	1H-Pyrrole, Indole acetic acid, Indole carbaldehyde	1H-Pyrrole-2-carboxylic acid Indole acetic acid 1H-Indole-2-carboxylic acid Indole carbaldehyde 2H-Pyrrol-2-one, 5-[[2-[(4-aminophenyl)methylene]-3,4-dimethyll]methylene]-3-ethyl-1,5-dihydro- 4-methyl	-
		Organic compound containing nickel, vanadium and/or nitrogen
Nickel	C31HxN4Ni	C4HxNNi, C14HxN2Ni	C8HxN2Ni, C10HxNi, C12HxN2Ni, C14HxNNi, C16HxNNi, C18HxNNi	C31HxN4Ni
Vanadium	C44HxN4V	C4HxV, C6HxN2V, C8HxN2V, C24HxN4V, C44HxN4V	C4HxV, C4HxNV, C5HxNV, C8HxN2V, C12HxN2V, C18HxN2V	C44HxN4V