Metal II complexes of ethambutol as good enzyme inhibitor and promising antioxidant

Ethambutoldihydrogenchloride [EMB] with chemical formula C[10]H[24]N[2]O[2].2HCl is ethane-1,2-diamine in which one hydrogen attached to each of the nitrogen is substituted by a 1-hydroxybutan-2-yl group [S,S-configuration]. It is an FDA approved drug and has been used for treatment of tuberculosis since 1960's. Prolong use of EMB has a side effect of visual impairment and in literature it is related with the depletion of Zn metal from the body. As it is a good chelating agent, many metal II complexes have been synthesized with anti-tubercular activity. The purpose of this work was to synthesize metal II complexes of EMB and to evaluate their antioxidant activity along with enzyme inhibition activity [acetylcholine esterase and protease]. The metals used for complex formation were Co, Zn, Fe, Cu and Ni. IR spectral data and physical parameters supported the complex formation. The obtained results showed the synthesized complexes as notable antioxidants and enzyme inhibitors

Potent AChE enzyme inhibition activity of Zizyphus oxyphylla: a new source of antioxidant compounds

The purpose of this study was to assess the antioxidant potential and enzyme inhibition of various fractions of Zizyphus oxyphylla. The plant metabolites were extracted in methanol and partitioned with n-hexane, chloroform, ethyl acetate and n-butanol successively. Phytochemical screening showed presence of alkaloids, terpenoids and flavonoids in ethyl acetate and n-butanol fractions. The antioxidant potential and acetylcholine esterase assay of all these fractions and remaining aqueous fraction was evaluated by using reported methods. The results revealed that chloroform soluble fraction exhibited highest percent inhibition of DPPH radical as compared to other fractions. It showed 95.01 +/- 0.37% inhibition of DPPH radical at a concentration of 120microg/mL. The IC[50] of this fraction was 13.20 +/- 0.27microg/mL, relative to butylated hydroxytoluene [BHT, a reference standard], having IC[50] of 12.10 +/- 0.29microg/mL. It also showed highest total antioxidant activity i.e. 1.723 +/- 0.34 as well as highest FRAP value [339.5 +/- 0.57TEmicroM/mL] and highest total phenolic contents [142.65 +/- 1.20 GAE mg/g] as compared to the other studied fractions. The fractions were also studied for Acetylcholine esterase enzyme [AChE] enzyme inhibition activity and n-butanol soluble fraction exhibited maximum inhibition [95.5 +/- 0.13mg/mL with IC[50] =9.58 +/- 0.08mg/mL relative to galanthamine [13.26 +/- 0.73mg/mL], while n- hexane soluble fraction [165.15 +/- 0.94mg/mL] showed non-significant. We are still working to isolate pure compounds for active fractions targeting potent inhibition responsible for some activities