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A series of 1,3,5-trisubstituted pyrazolines based homoleptic Ru(III) complexes of type [Ru(L 1-7 ) 3 ]$(PF 6 ) 3 (L 1-7 ¼ pyrazoline ligands) have been synthesized and characterized by elemental analysis, electronic spectroscopy, conductance measurements, thermogravimetric analysis (TGA), electron paramagnetic resonance (EPR), fourier transform infrared (FT-IR) spectroscopy and liquid chromatography mass spectroscopy (LC-MS). Octahedral geometry around ruthenium has been assigned in all complexes using EPR and electronic spectral analysis. All complexes have been investigated for their interaction with Herring Sperm (HS) DNA utilizing an absorption titration (K b ¼ 2.42-6.07 Â 10 5 M À1 ) and viscosity measurement study. The studies suggest the classical intercalative mode of binding. The DNA-binding property of the Ru(III) complexes was also investigated theoretically using a molecular docking study and suggests an intercalation binding mode between the complex and nucleotide base pairs. A cleavage study on pUC19 DNA has been performed by agarose gel electrophoresis. The results indicated that the Ru(III) complexes can more effectively promote the cleavage of plasmid DNA. The free ligands and their complexes have been evaluated for cytotoxicity activity against S. pombe cells at a cellular level. A comparative study of cellular level cytotoxicity values of the all compounds indicates that the metal complexes show better activity against S. pombe cells compared to the pyrazoline ligands. The complexes have been screened for their in vitro antibacterial activity against two Gram(+ve) and three Gram(Àve) microorganisms. Ru(III) complexes are good in vitro cytotoxic agents and 50% lethal concentration (LC 50 ) values are in range of 5.296-7.925 mg mL À1 . All newly synthesized Ru(III) complexes have been also evaluated for their in vitro antimalarial activity against Plasmodium falciparum strain [inhibition concentration (IC 50 ) ¼ 0.54-0.92 mg mL À1 ].

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Background Colletotrichum and Fusarium species are among pathogenic fungi widely affecting Coffea arabica L., resulting in major yield loss. In the present study, we aimed to isolate bacteria from root rhizosphere of the same plant that is capable of antagonizing Colletotrichum gloeosporioides and Fusarium oxysporum as well as promotes plant growth.ResultsA total of 42 Bacillus species were isolated, one of the isolates named BT42 showed maximum radial mycelial growth inhibition against Colletotrichum gloeosporioides (78%) and Fusarium oxysporum (86%). BT42 increased germination of Coffee arabica L. seeds by 38.89%, decreased disease incidence due to infection of Colletotrichum gloeosporioides to 2.77% and due to infection of Fusarium oxysporum to 0 (p < 0.001). The isolate BT42 showed multiple growth-promoting traits. The isolate showed maximum similarity with Bacillus amyloliquefaciens.Conclusion Bacillus species (BT42), isolated in the present work was found to be capable of antagonizing the pathogenic effects of Colletotrichum gloeosporioides and Fusarium oxysporum. The mechanism of action of inhibition of the pathogenic fungi found to be synergistic effects of secondary metabolites, lytic enzymes, and siderophores. The major inhibitory secondary metabolite identified as harmine (β-carboline alkaloids).