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A bacterial cellulose (BC) producing strain isolated from fermented fruit. Twenty BC producing bacteria were isolated from each the isolation sources (fermented fruits). The most potent strain was identified to be Komagataeibacter xylinus SB3.1 based on several morphological characteristics, biochemical tests and 16srRNA. The Komagataeibacter xylinus SB3.1. was produce BC within pH 4-9 and exhibit maximum BC production (2.4 g/L) at pH 6 in under static conditions for 7 days. The structure of BC produced from the tested strains was assayed by scanning electron microscope it was revealed the diameter of thin ribbons ranged from 34.34 nm to 39.16 nm and exhibits higher porosity (81.5%).In comparison with the specimen from model BC producer, Gluconacetobacter xylinus 10245. Based on these analyses, the isolated Komagataeibacter xylinus SB3.1 can efficiently produce BC, which can be applied for industrial manufacturing with potential features.

Herein, bacterial isolate HIS7 was obtained from contaminated soil and exhibited high efficacy to degrade pyrethroid insecticide cypermethrin. The HIS7 isolate was identified as Lysinibacillus cresolivuorans based on its morphology and physiology characteristics as well as sequencing of 16S rRNA. The biodegradation percentages of 2500 ppm cypermethrin increased from 57.7% to 86.9% after optimizing the environmental factors at incubation condition (static), incubation period (8-days), temperature (35 °C), pH (7), inoculum volume (3%), and the addition of extra-carbon (glucose) and nitrogen source (NH4Cl2). In soil, L. cresolivuorans HIS7 exhibited a high potential to degrade cypermethrin, where the degradation percentage increased from 54.7 to 93.1% after 7 to 42 days, respectively. The qualitative analysis showed that the bacterial degradation of cypermethrin in the soil was time-dependent. The High-Performance Liquid Chromatography (HPLC) analysis of the soil extract showed one peak for control at retention time (R.T.) of 3.460 min and appeared three peaks after bacterial degradation at retention time (R.T.) of 2.510, 2.878, and 3.230 min. The Gas chromatography–mass spectrometry (GC–MS) analysis confirmed the successful degradation of cypermethrin by L. cresolivuorans in the soil. The toxicity of biodegraded products was assessed on the growth performance of Zea mays using seed germination and greenhouse experiment and in vitro cytotoxic effect against normal Vero cells. Data showed the toxicity of biodegraded products was noticeably decreased as compared with that of cypermethrin before degradation.

Bacterial cellulose (BC) is a nanostructured material mainly produced by genus Gluconacetobacter displays unique physicochemical and mechanical properties therefore it has many potential applications in biomedical, biosensor, food and other industries. However, application of bacterial cellulose faced one of the main big problems in industry, viz., low productivity. Herein, this work was undertaken with a view to enhance the BC production using Komagataeibacter xylinus SB3.1 under static condition through study the effective culture parameters that played a vital role in nanofiber production. The results revealed the successful production of BC nanofibers using K. xylinus SB3.1 under static conditions as obviously indicated from the SEM image. FTIR and XRD affirmed both the chemical structure and crystallographic nature of cellulose I of the produced nanofibers. In the improvement effort, maximum yield of BC reached 6.54 g/L under optimal conditions including the use of mannitol and yeast extract as the sole source of carbon and nitrogen during an 8 day incubation period at 30 •C with 8% inoculum size which reveals to the increase in the nanofiber production 3.3 folded times than others with unoptimized condition under the same stationary conditions of growth. This also opens up the window for utilizing a new locally isolated K. xylinus SB3 in industrial manufacturing with potential features.

Aims: This study report the ability of some bacterial strain to degrade the phenanthrene which is a polycyclic aromatic hydrocarbon and to optimize the condition controlling the phenanthrene biodegradation. Study Design: Collect different petroleum contaminated sediment samples, isolate phenanthrenedegrading bacteria on media supplemented with phenanthrene as a unique carbon source, select and identify the most potent bacterial strain. Finally, some of the most biotic and abiotic parameters were optimized to enhance the bacterial biodegradation of phenanthrene.

The peel aqueous extract of Punica granatum was utilized to fabricate zinc oxide nanoparticles (ZnO-NPs) as a green approach. The synthesized NPs were characterized by UV-Vis spectroscopy, Fourier transform infrared (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy, which was attached to an energy dispersive X-ray (SEM-EDX). Spherical, well arranged, and crystallographic structures of ZnO-NPs were formed with sizes of 10–45 nm. The biological activities of ZnO-NPs, including antimicrobial and catalytic activity for methylene blue dye, were assessed. Data analysis showed that the antimicrobial activity against pathogenic Gram-positive and Gram-negative bacteria, as well as unicellular fungi, was observed to occur in a dose-dependent manner, displaying varied inhibition zones and low minimum inhibitory concentration (MIC) values in the ranges of 6.25–12.5 µg mL–1. The degradation efficacy of methylene blue (MB) using ZnO-NPs is dependent on nano-catalyst concentration, contact time, and incubation condition (UV-light emission). The maximum MB degradation percentages of 93.4 ± 0.2% was attained at 20 µg mL−1 after 210 min in presence of UV-light. Data analysis showed that there is no significant difference between the degradation percentages after 210, 1440, and 1800 min. Moreover, the nano-catalyst showed high stability and efficacy to degrade MB for five cycles with decreasing values of 4%. Overall, P. granatum-based ZnO-NPs are promising tools to inhibit the growth of pathogenic microbes and degradation of MB in the presence of UV-light emission.

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