Fig. 4

Effect of CON, CT10 and CT50 on gut metabolome of P. nigromaculatus tadpoles. Different letters indicated significant differences. (1) Cutin, suberine and wax biosynthesis, (2) Tryptophan metabolism, (3) Phenylalanine, tyrosine and tryptophan biosynthesis, (4) Folate biosynthesis, (5) Nicotinate and nicotinamide metabolism, (6) Arginine biosynthesis, (7) Alanine, aspartate and glutamate metabolism, (8) Biotin metabolism, (9) Tropane, piperidine and pyridine alkaloid biosynthesis, (10) Histidine metabolism, (11) Betalain biosynthesis, (12) One carbon pool by folate, (13) Ribotfavin metabolism, (14) Lysine biosynthesis, (15) Lysine degradation, (16) Arginine and proline metabolism, (17) Glycerophospholipid metabolism.