Bacillus niabensis OAB2: Outstanding bio-factory of selenium nanoparticles

This work deals with the synthesis of zinc oxide nanoparticles/activated carbon (ZnO NPs/AC) nanocomposites with different weight ratios (3:1, 1:1, and 1:3), where the antimicrobial, antiviral, and cytotoxicity impact of the formulated nanocomposites were evaluated versus the crude ZnO and AC samples. The formula (3:1; designated Z3C1) exhibited the utmost bactericidal effect against Gram positive group, unicellular and filamentous fungi. Regarding Gram negative group, the sample (Z3C1) was remarkably effective against Klebsiella pneumonia, unlike the case of Escherichia coli. Moreover, the whole samples showed negligible cytotoxicity against the human WI38 cell line, where the most brutality (4%) was exerted by 1000 µg/mL of the formula (Z1C3). Whilst, the formula (Z3C1) exerted the apical inhibition impact against Herpes simplex (HSV1) virus. Consequently, the synthesized (Z3C1) nanocomposite was sorted out to be fully characterized via different physicochemical techniques including FTIR, XRD, SEM, TEM, Zeta potential, TGA, and BET. XRD indicated a predominance of the crystalline pattern of ZnO NPs over the amorphous AC, while the FTIR chart confirmed an immense combination between the ZnO NPs and AC. SEM, TEM, and size distribution images illustrated that the fabricated ZnO NPs/AC was in the nanoscale size swung from 30 to 70 nm. The distinctive surface area of composite material, recording 66.27 m2/g, clearly disclosed its bioactivity toward different bacterial, fungal, and virus species.

Section: Methodsmentioning

confidence: 99%

Assessment of antimicrobial, cytotoxicity, and antiviral impact of a green zinc oxide/activated carbon nanocomposite

Hassan

Abol-Fotouh

Salama

et al. 2022

“…Therefore, the distribution of microbial-derived nanoselenium outside the cell is advantageous. Bacillus subtilis SE201412 could secrete nano-selenium with typical red color outside the cell after 6 h of culture, which had a shorter transformation time and better transformation effect compared with the existing reported selenium-enriched microorganisms 23 – 27 , but its specific transformation mechanism is not clear and needs further study.…”

Section: Resultsmentioning

confidence: 99%

“…The Bacillus sp. capable of preparing SeNPs have been reported as Bacillus niabensis OAB2 23 , Bacillus paramycoides SP3 24 , Bacillus mycoides SeITE01 25 , Bacillus sp. MSh-1 26 , Bacillus amyloliquefaciens SRB04 27 , etc.…”

Section: Resultsmentioning

confidence: 99%

Development and application of a new biological nano-selenium fermentation broth based on Bacillus subtilis SE201412

Huang

Wen

et al. 2023

In order to improve the functionality and additional value of agricultural products, this study developing nano-selenium fermentation broth and established a new application strategy of bio-nano-selenium by screening and identifying selenium-rich microorganisms. We isolated a new strain from tobacco waste and named it Bacillus subtilis SE201412 (GenBank accession no. OP854680), which could aerobically grow under the condition of 66,000 mg L−1 selenite concentration, and could convert 99.19% of selenite into biological nano-selenium (BioSeNPs) within 18 h. Using strain SE201412, we industrially produced the different concentrations of fermentation broth containing 5000–3000 mg L−1 pure selenium for commercial use. The synthesized selenium nanoparticles (SeNPs) were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nanoparticle tracking analysis (NTA). TEM and SEM results showed that SeNPs were distributed outside cells. NTA assay of fermentation broth indicated that the nanoparticles were spherical with an average particle size of 126 ± 0.5 nm. Toxicity test revealed that the median lethal dose (LD50) of the fermentation broth to mice was 2710 mg kg−1, indicating its low toxicity and high safety. In addition, we applied BioSeNP fermentation broth to rice and wheat through field experiments. The results showed that the application of fermentation broth significantly increased the total selenium content and organic selenium percentage in rice and wheat grains. Our findings provide valuable reference for the development of BioSeNPs with extensive application prospects.

“…The treatment of the strain Komagataeibacter hansenii KO28 by gamma irradiation was carried out adopting 60 Co gamma rays at a dose rate of 0.77 kGy/h 17 . Briefly, aliquots of 10 ml volume of the bacterial culture were prepared, then, divided into three sets; Control, set (A), and set (B).…”

Section: Methodsmentioning

confidence: 99%

A turning point in the bacterial nanocellulose production employing low doses of gamma radiation

Al-Hagar

Abol-Fotouh

2022

Self Cite

In the recent years, huge efforts have been conducted to conceive a cost-effective production process of the bacterial nanocellulose (BNC), thanks to its marvelous properties and broadening applications. Herein, we unveiled the impact of gamma irradiation on the BNC yield by a novel bacterial strain Komagataeibacter hansenii KO28 which was exposed to different irradiation doses via a designed scheme, where the productivity and the structural properties of the BNC were inspected. After incubation for 240 h, the highest BNC yield was perceived from the culture treated twice with 0.5 kGy, recording about 475% higher than the control culture. Furthermore, almost 92% of its BNC yield emerged in the first six days. The physicochemical characteristics of the BNCs were investigated adopting scanning electron microscope (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier transform infrared (FTIR). Additionally, the water holding capacity, water release rate, surface area (BET), and mechanical properties were configured for the BNC generated from the control and the irradiated cultures. As a whole, there were no significant variations in the properties of the BNC produced by the irradiated cultures versus the control, proposing the strain irradiation as a valuable, facile, and cheap route to augment the BNC yield.