In this paper, Jr.NiFe₂O₄ nanoparticles (NPs) were synthesized first time using the leaves extract of Juglans regia via a straightforward process. The physio and phytochemical analysis of plant confirm the presence of macromolecules which function as bio-reductant and stabilize the nanoparticles. The Jr.NiFe₂O₄ NPs were characterized by UV–visible, FTIR spectroscopy, PXRD pattern, SEM and TGA/DTA analysis. The nanoparticles proved to be optically active having a value of indirect bandgap of energy in the range of 1.53 eV. The Jr.NiFe₂O₄ NPs have the ability in scavenging 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) free radicals and showed 58.01% ± 1.2% scavenging activity at 100 µg/mL concentrations. The photocatalytic degradation study of ciprofloxacin (CIP) and Congo red (CR) reveals that the highest degradation rate was acquired for CIP using pH = 3, at 254 nm, while 85% of removal rate was analysed for CR. The kinetic studies in case of CR removal followed pseudo-first-order model with thermodynamic parameters (∆G° = − 5.87 kJ mol⁻¹ K, ΔH° = 1393.50 kJ mol⁻¹ and ΔS° = 22.537 kJ mol⁻¹ K) with error analysis. Overall, these data recommend an innovative inspiring application of a plant-mediated synthesis of Jr.NiFe₂O₄ NPs.

In the present study, naphthyl acetohydrazide (HL) ligand was prepared and used for the synthesis of new six amorphous transition metal (Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II)) complexes. All the compounds were characterized by elemental analysis, UV-vis, FT-IR, ¹H- and ¹³C-NMR, and Matrix-Assisted Laser Desorption Ionization (MALDI). The solubilization study was carried out by estimating the interaction between the metal complexes with surfactants viz. sodium stearate (SS) and Cetyltrimethylammonium bromide (CTAB). UV-Visible spectroscopy was employed to determine partitioning and binding parameters, whereas electrical conductivity measurements were employed to estimate critical micellar concentration (CMC), the extent of dissociation, and free energy of micellization. The CT-DNA interaction of synthesized compounds with DNA represents the major groove binding. The synthesized ligand and metal complexes were also tested against bacterial and fungal strains and it has been observed that Cu(II) complex is active against all the strains except Candida albicans, while Cd(II) complex is active against all bacterial and fungal strains except Pseudomonas. Among all compounds, only the Pd(II) complex shows reasonable activity against cervical cancer HeLa cell lines, representing 97% inhibition.

The microbial resistance to current antibiotics is increasing day by day, which in turn accelerating the development of new effective drugs. Several studies have proved the high antimicrobial potential of the interaction of several organic ligands with a variety of metal ions. In the present study, a conventional method has been adopted in the synthesis of twelve new heteroleptic complexes of cobalt (II), nickel (II), copper (II) and zinc (II) using three aldimines, namely, (HL₁ ((E)-2-((4-chloro-2-hydroxybenzylidene)amino)-3,4-dimethyl-5-phenylcyclopent-2-en-1-one), HL₂ ((Z)-3-((4-chlorobenzylidene)amino)-4-hydroxy-5-nitrobenzenesulfonic acid) HL₃ (2,2′-((1,2-phenylenebis(azaneylylidene))bis(methaneylylidene))diphenol)) as primary ligands, while phenyl glycine was the secondary ligand. The synthesized compounds were characterized by UV-vis, IR and multinuclear (¹H and ¹³C) NMR spectroscopy, elemental analysis, and electrical conductance. The IR study revealed the coordination of the aldimine derivatives with the -OH and N atom of imine moiety. In contrary to this, the phenyl glycine coordinated to the metal ions via oxygen of carboxylate and nitrogen of the amino group. The spectroscopic analysis unveiled the tetrahedral geometry of the synthesized metal (II) complexes, except for ligand HL₃ which exhibited octahedral geometry. The synthesized compounds generally showed antibacterial activity for all microbes, except Ni (II) complexes lacking sensitivity. Furthermore, to access the bioavailability, the synthesized complexes were screened for their solubilization in the micellar media of sodium lauryl sulphate. The metal complex–surfactant interaction was revealed by UV-vis spectroscopy and electrical conductivity measurements.

Food contaminated with fungi and their toxins is a problem that threatens many developing countries. Kingdom of Saudi Arabia depends on the exported grain and legume seeds. The study involved examination of 160 samples of rice and maize seeds collected from different locations in the Kingdom of Saudi Arabia. Heterogeneity in the 18s rRNA gene of toxigenic Alternaria sp. and Fusarium sp. was unraveled. The seeds were disinfected and cultured on Potato Dextrose Agar (PDA), Yeast Extract Sucrose (YES) media and incubated at 25 °C/7 days. The isolated fungi were subjected to 18s rRNA gene sequencing. Five toxins were extracted from maize and rice grains infected with isolated fungi. The isolated fungi were identified based on morphological and spores characters as Fusarium sp. and Alternaria sp. Molecular identification based on18s rDNA barcode' was performed due to its high degree of inter specific variability, conserved primer sites and multi-copy nature in the genome. Fusarium sp. produced the highest detected (2070 μg/kg) fumonisin especially in cereal production season 2011. The collected grain from Dammam recorded the highest percentage (5485.2 g/kg) of toxins. This work highlights that 50% of samples were found contaminated with toxins in various concentrations which impose a threat for public health and necessitate rapid identification methods for toxigenic fungi such as 18s rDNA sequencing.

Camels and goats fermented milk is a traditional product that consumed as a main type of food in nomadic areas of Saudi Arabia, and this bacterium is the predominant microorganism in the camelssheep milk that is responsible for milk fermentation. In this study, high qualities of fresh milk samples were selected, isolated, and identified total of samples with a fact of 10 fresh milk samples from five different areas in Riyadh City representing North, South, East, and West of Riyadh for analysis. Bacteria have been isolated as follows: Staphylococcus simulans, Erysipelothrix rhusiopathiae, Aeromonas Hydrophila, and Pseudomonas putida. In Camels and goats milk, the isolated bacteria were Staphylococcus sp bacteria and Pseudomonas putida with total of 50% of the study samples, and the isolated bacteria Kocuria rosea with 25% and bacteria Erysipelothrix rhusiopathiae with 15% and bacteria Aeromonas Hydrophila with 10%. Bacteria were identified using a definition of bacteria VITEK 2 and the use of identification systems API 50 CHL API 2C AUX, respectively. The average concentration psaudomonas and staphylococcus 7.4loglÛ CFU ml7.7loglÛ CFU ml. All isolates of bacteria have been shown in test results and were positive for antibiotics pseudomonas putida, kocuria rosea, Erysipelothrix rhusiopathiae, aeromonas hydrophila, and Staphylococcus simulant.

Wecollected 30 samples of cereal crops (Wheat, millet, barley, corn, and rice)stored and offered for sale in Riyadh area markets. It was found that most ofthese samples were contaminated with fungus Aspergillus sp.(73.2% ), and that the corn crop washighest to be hit by fungus Aspergillus sp. (23.3%) compared tothe rest of the crops (wheat 16.6 %), ( barley 13.3%), (millet 10%), and (rice10%). It appeared in this study that most isolated species have the ability toproduce aflatoxin. We studied the effect of temperature on the secretion ofaflatoxin in isolated fungi; and the results are illustrated in the temperaturetable.