Biogenic Synthesis of Novel Functionalized Selenium Nanoparticles by Lactobacillus casei ATCC 393 and Its Protective Effects on Intestinal Barrier Dysfunction Caused by Enterotoxigenic Escherichia coli K88

Abstract

Selenium (Se) is an essential element for human and animal health. Biogenic selenium nanoparticles (SeNPs) by microorganism possess unique physical and chemical properties and biological activities compared with inorganic Se and organic Se. The study was conducted to investigate the mainly biological activities of SeNPs by Lactobacillus casei ATCC 393 (L. casei 393). The results showed that L. casei 393 transformed sodium selenite to red SeNPs with the size of 50–80 nm, and accumulated them intracellularly. L. casei 393-SeNPs promoted the growth and proliferation of porcine intestinal epithelial cells (IPEC-J2), human colonic epithelial cells (NCM460), and human acute monocytic leukemia cell (THP-1)-derived macrophagocyte. L. casei 393-SeNPs significantly inhibited the growth of human liver tumor cell line-HepG2, and alleviated diquat-induced IPEC-J2 oxidative damage. Moreover, in vivo and in vitro experimental results showed that administration with L. casei 393-SeNPs protected against Enterotoxigenic Escherichia coli K88 (ETEC K88)-caused intestinal barrier dysfunction. ETEC K88 infection-associated oxidative stress (glutathione peroxidase activity, total superoxide dismutase activity, total antioxidant capacity, and malondialdehyde) was ameliorated in L. casei 393-SeNPs-treated mice. These findings suggest that L. casei 393-SeNPs with no cytotoxicity play a key role in maintaining intestinal epithelial integrity and intestinal microflora balance in response to oxidative stress and infection.

Effects of Selenium- and Zinc-Enriched Lactobacillus plantarum SeZi on Antioxidant Capacities and Gut Microbiome in an ICR Mouse Model

“…Selenium is an essential element that must be exogenously provided to reach the requirement of human and animal health [ 43 ]. The toxicity order of selenium species from high to low is selenate, selenite, nano-selenium, and lactomicro-selenium [ 44 ].…”

Tunable photoluminescence properties of selenium nanoparticles: biogenic versus chemogenic synthesis

“…As opposed to conventional chemogenic syntheses, biogenic approaches give rise to thermodynamically stable yet structurally diverse SeNS products in a safe and eco-friendly manner, avoiding the need of post-production treatments [2]. To date, biogenic SeNMs were investigated for their applications in (i) biomedicine, as antimicrobial [19][20][21][22][23][24][25][26][27], anticancer [27][28][29][30][31][32][33][34][35][36][37][38] and antioxidant [27,[39][40][41] agents, due to their high biocompatibility towards eukaryotic in vitro and in vivo systems [22,28,40,42], (ii) photocatalysis, and (iii) biosensing or pollutant adsorption [43][44][45][46], leaving still unveiled the potentiality of these NSs as a bioimaging tool. In particular, the PL properties of SeNPs produced by bacteria just recently began to be explored, as in the case of those recovered from the environmental isolate Stenotrophomonas maltophilia SeITE02 under metabolically controlled growth conditions [6].…”

Phytogreen synthesis of multifunctional nano selenium with antibacterial and antioxidant implications

“…The antibacterial responses of nSe have been documented against major infection causing bacteria including E. coli [10,22], S. aureus [9,22,23], P. aeruginosa, and Proteus mirabilis [23]. Nanoselenium can be synthesized by different methods such as: (a) physical which include laser ablation, ultraviolet (UV) irradiation, hydrothermal [22,24,25], (b) chemical which include catalytic reduction, acid decomposition [26] and, (c) biogreen synthesis which rely on the use of certain bacteria [9,16,27,28], fungi [29] or plants species [30][31][32]. Amongst all, biogreen synthesis of nSe avoids the utilization of toxic reducing agents and post-modification steps which promotes their swift application in the food and medical industries.…”