Nanotechnology is one of the most emerging fields in the recent years. In the current investigation, we report the biosynthesis of iron nanoparticles (Fe-NPs) employing Alternaria alternata fungus, which is an eco-friendly process for the synthesis of metallic nanoparticles. Fe-NPs were synthesized through the reduction of aqueous Fe 3+ ion in the dark conditions. Ultraviolet-visible spectrum of the aqueous medium containing iron ion showed a peak at 238 nm and another peak at 265 nm. The forming of nanoparticles was confirmed by transmission electron microscope, scanning electron microscope and energy-dispersive x-ray. The morphology of nanoparticles is found to be cubic shapes mostly and the average particle diameter as determined by scanning electron microscope was found to be 9±3 nm. Fe-NPs showed antibacterial activity against both Gram-positive and Gram-negative bacteria used in this study due to its oxidative damage for bacterial cell wall. Iron nanoparticles show more antimicrobial activity to Bacillus subtilis than Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa.

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Composting of the solid waste generated in large amount in a short time interval from olive industry environmentally very attractive due to increasing its value. On the other hand various authors showed that the characteristics of humic acids depend on the parent material they are extracted of, in addition to many other factors including composting conditions and geographical region. In the present work four samples of pure solid olive mill waste (olive cake) was naturally composted under four different atmospheric conditions without addition of any plant residues or any nutrients, for more than one year. Humic acids (HAs) were extracted from the composts and they were characterized by elemental analysis, FTIR, UV-visible spectroscopy and titration for reactive groups. The results show that the compost prepared as a compact small sphere of diameter 20cm and kept in door at room temperature for more than one year gives a reduced form of humic acids of high maturity, high aromatic content, high carboxylic and phenolic contents and highest chelating ability for Cu +2 ions when compared with the results of five literature concerning commercial humic acids, The results of biological activity tests indicate in vitro, good antioxidant and anti bacterial activity, also exhibited mild antitumer but weak antiviral activity.