Schiff bases plays vital role in various fields especially in industry and biology. In the present study, a series of ternary mononuclear Schiff base transition metal complexes [ML(tmen)], (where M = Cu(II), Ni(II), Zn(II) and Co(II) ions; L = Schiff base ligand derived from L-tryptophan and 2’-hydroxyacetophenone; tmen-N,N,N’,N’ tetramethylethylenediamine) were synthesized and characterized by molar conductance, elemental analysis and spectral studies such as UV-Vis., and FTIR. Non-electrolytic nature of the complexes were confirmed by molar conductance. Tridentate coordination nature of Schiff base ligand was confirmed on the basis of FTIR spectra. In vitro antimicrobial studies were carried out against bacterial strains such as S. aureus, Bacillus sps., E. coli, and P. aeruginosa and fungal strains such as A. flavus, Rhizopus and Mucor. In addition, in vitro larvicidal and antioxidant studies were also performed for the Schiff base ligand and synthesized metal complexes.