DNA Cleavage Mechanism by Metal complexes of Cu(II), Zn(II), Mn(II) and Co(II) with a Schiff-base Ligand

Metal ions and metal complexes are important components of nucleic acid biochemistry, participating both in regulation of gene expression and as therapeutic agents. Four new transition  metal complexes of Cu(II), Ni(II), Co(II) and Zn(II) have been synthesized from a new Schiff base ligand derived from 4-bromo aniline, 2-hydroxy-1-naphthaldehyde. The ligand and its complexes have been characterized by spectral analysis. The in vitro antimicrobial activity of the investigated compounds was tested against the bacteria such as Bacillus subtilis, Escherichia coli and fungi Aspergillus flavus and Aspergillus niger. The data indicate that most of the metal complexes have higher antibacterial activity than the free ligand. DNA cleavage experiments performed on pBR322 DNA using metal complexes in the presence of H2O2 showed that all the complexes afford a pronounced DNA cleavage

Phytochemical Content and Antioxidant Potential of Citrus reticulata Collected in the Thanjavur District, South India

This study was designed to investigate the phytochemical and the antioxidant activities of fruits, peels and leaves extracts of Citrus reticulata. The total alkaloids, saponin, phenolic acid and flavonoids were determined spectrophotometrically while antioxidant potentials were evaluated with 2,2’-diphenyl-1-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2) protocols. The fruit extract shows the highest phenolic acid content of 33.94 mg/GAE/g. Flavonoids content was highest in the peels extract 14.30 mg/QE/g. All the extracts showed significant antioxidant activities H2O2, DPPH along a concentration gradient. Antioxidant capacity is also high in the test plant suggesting its biomedicinal value to human health