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The quest for eco-friendly and biocompatible nanoparticles (NPs) is an urgent issue in the agenda of the scientific community and applied technology, which compressing synthesis routes. For the first time, a simple route for the biosynthesis of functionalized CuFe-hybrid nanocomposites (FCFNCs) was achieved using Streptomyces cyaneofuscatus through a simultaneous bioreduction strategy of Cu and Fe salts. The suitability of FCFNCs was evaluated medically and environmentally as an anticancer agent, antimicrobial agent and dye bio-sorbent. The physicochemical characteristics of FCFNCs using XRD, EDX, elemental mapping, FTIR, UV–Vis., TEM and ζ-potential confirmed the formation of spheres agglomerated into chains (37 ± 2.2 nm), self-functionalized nanocomposite by proteinaceous moieties with considerable stability (− 26.2 mV). As an anticancer agent, FCFNCs displayed the highest apoptotic impact (> 77.7%) on Caco-2, HepG-2, MCF-7 and PC-3 cancer cells at IC50 ≤ 17.21 μg/mL with the maximum up regulation of p53 and caspase 3 expression and the lowest Ki-67 level, relative to both functionalized CuNPs (FCNPs) and FeNPs (FFNPs). Meanwhile, it maintained the viability of normal human cells by EC100 up to 1999.7 μg/mL. Regarding the antimicrobial activity, FCFNCs offered > 70% growth reduction among wide spectrum prokaryotic and eukaryotic pathogens. Additionally, the synergistic feature of FCFNCs disintegrated the pre-established biofilm and algal growth in a dose-dependent manner. However, as a bio-sorbent, FCFNCs decolorized > 68% of malachite green and congo red dyes (200 mg/L), reflecting considerable remediation efficiency, confirmed by FTIR of FCFNCs- adsorbed dyes and microtoxicity/cytotoxicity of solutions after remediation. This study offers new insights into promising CuFe-hybrid nanocomposites for recruitment in several applications.

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Twelve selected phenol-degrading bacterial isolates were obtained on phenol agar plates using culture enrichment technique. Molecular identification of the isolates was performed using eubacterial 16S rRNA PCR specific primers. Based on 16S rDNA sequence analysis, the results revealed that the majority of the isolates (8 out of 12) are affiliated to the g-subdivision of Proteobacteria. Four out of the eight isolates are closely related to the genus Acinetobacter. Molecular heterogeneity among the phenol-degrading isolates was further investigated by using rep-PCR chromosomal fingerprinting and correlated with plasmid and antibiotic profile analysis. Rep-PCR results strongly confirmed that the bacterial isolates from different environmental sites produced different fingerprinting patterns. The mineralization of phenol by all isolates was evaluated using 14C-labeled phenol assay. Phenol mineralization ranged from 55% (W-17) to 0.4% (Sea-9). This was further confirmed by the detection of several monoaromatic and polyaromatic degrading genes, e.g., pheA, MopR, XylE, and NahA. In addition, catalytic enzymes such as catalase and dioxygenase were also monitored.

Natural environment is a wealthy source of bionanofactories that invested in green approaches as the fabrication of biomimetic nanomaterials. The current study points out the importance of microbial activity in metal bioremediation, green synthesis of NPs, and global biogeochemical cycles of bioactive metals as well. It describes for the first time the synchronous biosynthesis of zero-(intracellular) and one-dimensional (extracellular) copper oxide nanoparticles (CuO-NPs) via Proteus mirabilis 10B. This bionanofactory represents key location of reduction and stabilization, and its exopolysaccharide additionally provides nucleation and growth site for CuO-NPs. The as-synthesized CuO-NPs were characterized; UV-Vis spectroscopy revealed surface plasmon resonance at 275 and 430 nm for intracellular and extracellular CuO-NPs, respectively. XRD reflected crystalline, pure phase monoclinic structure CuO-NPs. EDX illustrated strong copper signal with atomic percentages 32.3% (intracellular) and 14% (extracellular) CuO-NPs. However, ζ-potential recorded −62.5 and −43.8 mV with PDI 0.207 and 0.313 for intracellular and extracellular CuO-NPs, respectively, confirming the colloidal stability and monodispersity. Moreover, TEM micrographs depicted quasi-spherical intracellularly sequestered CuO-NPs (10 nm). Unexpectedly, extracellular CuO-NPs exhibited rod-, needle-, and wire-shaped with 17-37.5 nm in width and 112-615 nm in length. The antagonistic activity of both types of CuO-NPs was evaluated against Gram-negative and Gram-positive bacteria (aerobic and anaerobic), biofilm, yeast, mold, and algae. The potent antagonistic efficacy of CuO-NPs was displayed which encourages its utilization in controlling microbial contamination. Finally, the promising metabolic activity of Proteus mirabilis 10B can be exploited in simultaneous and beneficial applications for human and the surrounding ecosystem.

Sericin is one of the main components of silk proteins, which has numerous biomedical applications because of its antioxidant, anticancer and antimicrobial properties.

ABSTRACT:The aim of this study was to look for high efficient bioflocculant-producing microorganisms. Among 36 bacterial colonies isolated from a crude petroleum oil sample, three of them as Bacillus subtilis and Pseudomonas spp. exhibited flocculation activity exceeding 90 % after 3 days of cultivation. They were identified by 16 S rDNA sequence analysis as Bacillus subtilis and Pseudomonas sp. Spectroscopic analysis of the polymers by nuclear magnetic resonance and fourier-transform infrared revealed that the polymers were glycoproteins. These polymers were soluble in water and insoluble in any organic solvents tested. The effects of bioflocculant dosage, temperature and pH on the flocculation activity were evaluated. The maximum bioflocculation activities were observed at an optimum bioflocculant dosage of 3.5 mg/L (strains Bacillus subtilis and Pseudomonas) and 5.0 mg/L (strain CPO14), respectively. In addition, these biopolymers were able to flocculate kaolin suspension (5 g/L) over a wide range of pH (pH 3-9) and temperature (5-50 °C) tested in the presence of CaCl 2 . The highest flocculation activities of strains CPO8, CPO13 and CPO14 were 96.03 %, 92.17 % and 97.59 %, respectively in the early stationary phase (at 24 h), while the cell production reached its maximum in the stationary phase (at 72 h). Their efficient flocculation capabilities suggest potential applications in industries.