Synthesis, spectral aspects and biological activities of 5-hydroxy-2-nitrobenzaldehydethiosemicarbazone and their Mn(II), Co(II) and Ni(II) complexes.

The ligation behavior of 5-hydroxy-2-nitrobenzaldehydethiosemicarbazone (L) and its Mn(II), Co(II) and Ni(II) complexes has been synthesized and characterized by Elemental analysis, Electronic, FT-IR, Raman, EPR spectral techniques and Cyclic voltammetric study. The ligand (L) belongs to triclinic system with P1 space group. The IR spectral data of ligand indicate the taking part of sulphur and azomethine nitrogen in coordination to the central metal ion. The electronic, FT-IR and EPR spectral studies reveals all the complexes are distorted octahedral geometry. The synthesized ligand and its metal(II) complexes were tested for their antioxidant activity by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method and antibacterial activity against E.coli, Staphylococcus aureus, Bacillus subtilis, Salmonella typhi and Klebsiella pneumonia. The antibacterial and antioxidant activities of the ligand and its metal complexes had shown moderate to good activity, among all the compounds Ni(II) complex had shown more activity.

Synthesis, spectroscopic characterization and antimicrobial activity studies of 2-Butyl-4-chloro-5-formylimidazole thiosemicarbazone and its manganese (II) complex.

A novel chelating tridentate organic ligand, 2-Butyl-4-chloro-5-formylimidazole thiosemicarbazone(L) is synthesized and characterized by using spectroscopic techniques like elemental analysis, FT-IR, 1H and 13C NMR, UV-vis and Mass spectrometry. The free ligand is then used for the synthesis of Mn(II) complex thoroughly characterized by FT-IR, EPR and electronic spectral analysis. The complex is found to have characteristic d5 electronic spectrum and the geometry of the complex is identified as octahedron based on the g value obtained from the EPR spectrum. Both the ligand and Mn(II)L2 compounds are found to exhibit similar antimicrobial activity against the gram –ve and gram +ve bacteria.

Antibiogram of Vibrio species isolated from diseased Penaeus monodon [Fab]

Various antibiotics belonging to beta lactum, Rifampicin, Tetracycline, Quinolone, Aminoglycoside and synthetic groups were selected against vibrio species viz. V.fluvialis, V. furnissi, and V. splendidus, isolated from the diseased Penaeus monodon. The study revealed that among 15 antibiotics used, 12 showed sensitivity against V. fluvialis. In Vibrio furnissi among 16 antibiotics tested, 11 showed sensitivity, among 21 antibiotics tested, against V. splendidus, showed sensitivity against 14 antibiotics. Various antibiotics tested, ciprofloxacin was found to be more effective against all the test organisms