AUTHOR=Liu Pei , Long Haiyu , Cheng Han , Liang Mengdi , Liu Zhengwei , Han Zhenlian , Guo Zhen , Shi Hao , Sun Min , He Shuai 

TITLE=Highly-efficient synthesis of biogenic selenium nanoparticles by Bacillus paramycoides and their antibacterial and antioxidant activities

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2023.1227619

DOI=10.3389/fbioe.2023.1227619

ISSN=2296-4185

ABSTRACT=<p><bold>Introduction:</bold><italic>Bacillus</italic> species are known for their ability to produce nanoparticles with various potential applications.</p><p><bold>Methods:</bold> In this study, we present a facile approach for the green synthesis of selenium nanoparticles (Se NPs) using the biogenic selenate-reducing bacterium <italic>Bacillus paramycoides</italic> 24522. We optimized the growth conditions and sodium selenite reduction efficiency (SSRE) of <italic>B. paramycoides</italic> 24522 using a response surface approach.</p><p><bold>Results:</bold> Se NPs were synthesized by reducing selenite ions with <italic>B. paramycoides</italic> 24522 at 37 °C, pH 6, and 140 r/min, resulting in stable red-colored Se NPs and maximal SSRE (99.12%). The synthesized Se NPs demonstrated lethality against <italic>Staphylococcus aureus</italic> and <italic>Escherichia coli</italic> with MICs of 400 and 600 μg/mL, and MBCs of 600 and 800 μg/mL, respectively, indicating the potential of Se NPs as antibacterial agents. Furthermore, the Se NPs showed promising antioxidant capabilities through scavenging DPPH radicals and reducing power.</p><p><bold>Discussion:</bold> This study highlights the environmentally friendly production of Se NPs using <italic>B. paramycoides</italic> 24522 and their possible applications in addressing selenium pollution, as well as in the fields of environment and biotechnology.</p>