Biomedical and Catalytic Applications of Gold and Silver-Gold Alloy Nanoparticles Biosynthesized Using Cell-Free Extract of Bacillus Safensis LAU 13: Antifungal, Dye Degradation, Anti-Coagulant and Thrombolytic Activities.

This study investigated the green biosynthesis of gold (Au) and silver-gold alloy (Ag-Au) nanoparticles using cell-free extract of Bacillus safensis LAU 13 strain (GenBank accession No: KJ461434). The biosynthesized AuNPs and Ag-AuNPs were characterized using UV-Vis spectroscopy, Fourier-transform infrared spectroscopy, and transmission electron microscopy. Evaluation of the antifungal activities, degradation of malachite green, anti-coagulation of blood, and thrombolysis of human blood clot by the biosynthesized nanoparticles were investigated. The AuNPs and Ag-AuNPs had maximum absorbance at 561 and 545 nm, respectively. The FTIR peaks at 3318, 2378, 2114, 1998, 1636, 1287, 446, 421 cm-1 for AuNPs; and 3310, 2345, 2203, 2033, 1636, 1273, 502, 453, 424 cm-1 for Ag-AuNPs indicated that proteins were the capping and stabilization molecules in the biosynthesized nanoparticles. The particles were fairly spherical in shape with size of 10-45 nm for AuNPs and 13-80 nm for Ag-AuNPs. Moreover, energy dispersive X-ray analysis of AuNPs revealed gold as the most prominent metal in the AuNPs solution, while silver and gold were the most prominent in the case of Ag-AuNPs. Selected area electron diffraction showed the biosynthesized nanoparticles as crystal structures with ring shape pattern. AuNPs and Ag-AuNPs displayed growth inhibitions of 66.67-90.78% against strains of Aspergillus fumigatus and A. niger at concentration of 200 µg/ml , and remarkable degradation (> 90%) of malachite green after 48 h. Furthermore, the nanoparticles prevented coagulation of blood, and also completely dissolved blood clots, indicating the biomedical potential of AuNPs and Ag-AuNPs in the management of blood coagulation disorders. This is the first report of the synthesis of AuNPs and Ag-AuNPs using a strain of B. safensis for biomedical and catalytic applications.

Paper wasp nest-mediated biosynthesis of silver nanoparticles for antimicrobial, catalytic, anticoagulant, and thrombolytic applications.

Biosynthesis of silver nanoparticles (AgNPs) using nest extract of paper wasp (Polistes sp) was investigated in this work. The AgNPs were characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM), and evaluated for antibacterial, antifungal, dye degradation, blood anticoagulation, and blood clot dissolution (thrombolytic) activities. The crystalline polydispersed AgNPs with size range of 12.5-95.55 nm absorbed maximally at 428 nm and showed anisotropic structures of sphere, triangle, hexagon, rod, and rhombus. The FTIR data showed prominent peaks at 3426 and 1641 cm-1, which indicate the involvement of phenolics compounds and proteins in the synthesis of AgNPs. The prominence of Ag in the EDX spectra showed that indeed, AgNPs were formed. The AgNPs showed potent antibacterial activities (12-35 mm) against three multi-drug strains of Pseudomonas aeruginosa and Klebsiella granulomatis. While the growth of Aspergillus flavus and Aspergillus niger was completely suppressed, the AgNPs produced growth inhibition of 75.61 % against Aspergillus fumigatus at 100 µg/ml. Furthermore, the AgNPs degraded malachite green to the tune of 93.1 %. The AgNPs also prevented coagulation of blood, while it completely dissolved preformed blood clots within 5 min showing the potent anticoagulation and thrombolytic activities. This study, which is the first of its kind to use nest extract of paper wasp for the synthesis of nanoparticles, has shown that the biosynthesized AgNPs could be deployed for biomedical and catalytic applications.

Effects of heat stress on some blood parameters and egg production of Shika Brown layer chickens transported by road.

The effects of vitamins C and E on layer chickens transported by road for 6 h during the hot dry season were investigated. Two experimental groups consisting of thirty Shika Brown layers were separately administered vitamins C and E orally just before transportation, while another 30 layers, which were only given sterile water, served as control. Blood samples analyzed before and after transportation in the control layers showed a decrease (p<0.05) in total white blood cell, (p<0.01) lymphocyte and monocyte values, and a significant (p<0.05) and (p<0.001) increase in the values of eosinophils and heterophils post-transportation, respectively. In the experimental groups, post-transportation values of total white blood cells, eosinophils and monocytes were not different (p>0.05) from those obtained before transportation. Heterophil/lymphocyte values were highest in the control group. The result showed that transportation was stressful for the control layers. Post-transportation egg production was not significantly (p>0.05) different in the vitamin E treated group, but values recorded for the vitamin C and control groups were significantly (p<0.05) and (p<0.001) reduced compared to pre-transportation. In conclusion, vitamins C and E administration ameliorated the adverse effect of road transportation stress during the hot dry season.

Effects of heat stress on some blood parameters and egg production of Shika Brown layer chickens transported by road

The effects of vitamins C and E on layer chickens transported by road for 6 h during the hot dry season were investigated. Two experimental groups consisting of thirty Shika Brown layers were separately administered vitamins C and E orally just before transportation, while another 30 layers, which were only given sterile water, served as control. Blood samples analyzed before and after transportation in the control layers showed a decrease (p<0.05) in total white blood cell, (p<0.01) lymphocyte and monocyte values, and a signifcant (p<0.05) and (p<0.001) increase in the values of eosinophils and heterophils post-transportation, respectively. In the experimental groups, post-transportation values of total white blood cells, eosinophils and monocytes were not different (p>0.05) from those obtained before transportation. Heterophil/lymphocyte values were highest in the control group. The result showed that transportation was stressful for the control layers. Post-transportation egg production was not signifcantly (p>0.05) different in the vitamin E treated group, but values recorded for the vitamin C and control groups were signifcantly (p<0.05) and (p<0.001) reduced compared to pre-transportation. In conclusion, vitamins C and E administration ameliorated the adverse effect of road transportation stress during the hot dry season.