The invention discloses reduction complex nitrogen monoxide bacteria strain and its use. It is mesophilic pseudomonas sp. which is bacillary, single arrange, 0.6-2.5 um diameter, no sheath, no spore, 2-3 flagellum forming bank, gram staining negative. Its colony is milk white, circular, toughness, etc. Its strain uses complex NO as final electron acceptor. Its purpose is to regenerate Fe(II)EDTA solution by biologic method includes the following steps: Fe(II)EDTA absorbing NO to form Fe(II)EDTA-NO; adding certain carbon source to reduce Fe(II)EDTA-NO into N2 and regenerate the Fe(II)EDTA. The formed Fe(II)EDTA-NO has the advantages of high biological reducing efficiency, NO processing load, high bioactivity and reducing the Fe(III)EDTA. |