Development, characterization and in vitro bile salts binding capacity of selenium nanoparticles stabilized by soybean polypeptides

Preparation, physicochemical characterization, and immunomodulatory activity of ovalbumin peptide-selenium nanoparticles

During the preparation and development of selenium nanoparticles (SeNPs), natural bioactive peptides are added to enhance their physicochemical characteristics and functional properties. Among these properties, immunomodulatory activities, which include activating immune cells to strengthen immunity, constitute the major functions of the immune system. To obtain SeNPs with enhanced immunomodulation, ovalbumin peptide (OP) was used as a stabilizer, yielding OP-SeNPs. The physicochemical properties of OP-SeNPs were characterized. RAW264.7 macrophages were used as a model to investigate the immunomodulatory activity of OP-SeNPs. Results indicate that OP-SeNPs were zero-valent and amorphous, with a particle size of 82.23 ± 1.77 nm. SeNPs demonstrated positive interactions with the -OH, CO, CN, and NH groups of OP. In addition, OP-SeNPs activated RAW264.7 macrophages by increasing NO secretion and enhancing pinocytosis activity, indicating their ability to enhance immunomodulatory effects. Therefore, this study provides a theoretical basis for the construction and characterization of bioactive peptides and SeNP complexes.

Screening, characterization, and potential anti-hangover ability of selenium nanoparticle-enriched lactobacillus

This study aimed to develop a selenium nanoparticles (SeNPs)-enriched probiotic strain with potential anti-hangover effects. Pediococcus acidilactici JW-015 was screened for its high tolerance to inorganic selenium (up to 80 mM sodium selenite) and efficient synthesis of SeNPs, achieving a selenium accumulation concentration of 6974 ± 90.71 μg/g, with SeNPs accounting for 86.54% ± 2.48%. Safety and probiotic properties were evaluated, confirming that JW-015 is a safe probiotic strain and that selenium enrichment enhanced its probiotic properties. Furthermore, JW-015 demonstrated significant anti-hangover efficacy, with selenium enrichment improving the oxidative stress capacity, alcohol tolerance, alcohol degradation ability, and relevant enzyme activities (ADH and ALDH) of the strain. This study provides a promising bio-carrier for SeNPs transformation and expands the applications of selenium-enriched LAB.

Selenium Nanoparticles Derived from Moringa oleifera Lam. Polysaccharides: Construction, Stability, and In Vitro Antioxidant Activity

Selenium nanoparticles (SeNPs) have drawn considerable attention to biomedicine, the food industry, and cosmetics due to their strong antioxidant potential and low toxicity. However, their poor stability limits broader applications. A promising strategy to overcome this limitation involves combining SeNPs with polysaccharides. In this study, selenium nanoparticles (MOLP-SeNPs) were synthesized using Moringa oleifera Lam. polysaccharide (MOLP) as a stabilizer and dispersant within a redox system comprising sodium selenite and ascorbic acid. The structural characteristics of the synthesized MOLP-SeNPs were analyzed using spectroscopy. Additionally, their thermal and storage stability was evaluated, and their antioxidant activity was explored through simulated digestion in vitro and a HepG2 cell oxidative stress model. The results demonstrated that well-dispersed, zero-valent MOLP-SeNPs showing a mean particle size of 166.58 nm were synthesized successfully through an MOLP-to-sodium selenite ratio of 2.8:3 at pH 7.3 and 35 °C. The MOLP-SeNPs exhibited excellent stability during preparation. In simulated in vitro digestion and H2O2-induced oxidative stress experiments on HepG2 cells, MOLP-SeNPs displayed strong free radical scavenging capacity while improving antioxidant activity. Cellular experiments deeply revealed that pretreatment with MOLP-SeNPs significantly improved cell viability and provided a pronounced protective effect against oxidative damage. In conclusion, MOLP-SeNPs represent a novel antioxidant with promising applications in food and biomedicine.

Synthesis of Nano-Selenium from Bombyx batryticatus Polypeptide and Exploring Its Antioxidant and Skin Whitening Ability

To increase the stability of selenium in nano state and further improve its antioxidant and skin whitening ability, Bombyx batryticatus polypeptide (BBPP) was prepared. The optimum synthesis conditions of Bombyx batryticatus polypeptide nano-selenium (BBPP-SeNPs) were determined by a double-peak method. BBPP-SeNPs were characterized by transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), and particle size analysis (PSS). The 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), superoxide anion free radical scavenging rate, and total antioxidant capacity of BBPP, vitamin C (VC), and BBPP-SeNPs were measured for comparison. The inhibitory ability of BBPP and BBPP-SeNPs on tyrosinase was measured. Using mouse modeling, the skin whitening ability of VC and BBPP-SeNPs was measured. The results showed that the optimal conditions were obtained when the concentration of BBPP was 0.16 mg/mL, sodium selenite was 0.01 mol/L, ultrasound was carried out for 30 min, ascorbic acid was added in 0.04 mol/L, and stirring temperature was 20 °C for 4 h. The antioxidant capacity of BBPP-SeNPs has significantly improved. It can be observed that BBPP-SeNPs has obvious scavenging ability on skin-reactive oxygen species through a Reactive Oxygen Species (ROS) staining section. Through Hematoxylin-Eosin (H&E) staining, it can be proven that BBPP-SeNPs has a high security threshold.

Selenium bio-nanocomposite based on extracellular polymeric substances (EPS): Synthesis, characterization and application in alleviating cadmium toxicity in rice (Oryza sativa L.)

Selenium nanoparticles (SeNPs) have gained significant attention owing to their favorable bioavailability and low toxicity, making them widely applications in the fields of medicine, food and agriculture. In this study, bacterial extracellular polymeric substances (EPS) were used as a novel stabilizer and capping agent to prepare dispersed SeNPs. Results show that EPS-SeNPs presented negative potential (-38 mV), spherical morphologies with average particle size about 100-200 nm and kept stable at room temperature for a long time. X-ray diffraction (XRD) analysis demonstrated that the synthesized nanoparticles were pure amorphous nanoparticles, and X-ray photoelectron spectroscopy (XPS) spectrum showed a spike at 55.6 eV, indicating the presence of zero-valent nano‑selenium. Fourier-transform infrared spectroscopy (FTIR) and three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy analysis confirmed proteins and polysaccharides in EPS played a crucial role in the synthesis of EPS-SeNPs. Compared to EPS or sodium selenite (Na2SeO3), EPS-SeNPs showed a relatively moderate result in terms of scavenging free radicals in vitro. In contrast, EPS-SeNPs demonstrated lower toxicity to rice seeds than Na2SeO3. Notably, the exogenous application of EPS-SeNPs effectively alleviated the growth inhibition and oxidative damaged caused by cadmium (Cd), and significantly reduced Cd accumulation in rice plants.

Synthesis, characterization, biological activity, and in vitro digestion of selenium nanoparticles stabilized by Antarctic ice microalgae polypeptide

A new type of uniformly dispersed selenium nanoparticles (SeNPs) was prepared using Antarctic ice microalgae polypeptides (AIMP) as the stabilizer and dispersant. Different characterization techniques and tests show that the SeNPs are effectively combined with AIMP through physical adsorption and hydrogen bonding to form a more stable structure. Orange-red, zero-valence, amorphous, and spherical AIMP-SeNPs with a diameter of 52.07 ± 1.011 nm and a zeta potential of -41.41 ± 0.882 mV were successfully prepared under the optimal conditions. The AIMP-SeNPs had significantly higher DPPH, ABTS and hydroxyl radicals scavenging abilities compared with AIMP and Na2SeO3, and prevented the growth of both Gram-negative and Gram-positive bacteria by disrupting the integrity of cell walls, cell membranes and mitochondrial membranes. The AIMP-SeNPs had higher gastrointestinal stability compared with SeNPs. Thus, this research highlights the crucial role of AIMP as a biopolymer framework in the dispersion, stabilization, and size management of SeNPs and concludes that AIMP-SeNPs can be exploited as a potent antioxidant supplement and antibacterial substance in foods and medicine.

Structural Characterization and In Vitro Antioxidant, Hypoglycemic and Hypolipemic Activities of a Natural Polysaccharide from Liupao Tea

This study extracted and purified a natural polysaccharide (TPS-5) that has a molecular weight of 48.289 kDa from Liupao tea, a typical dark tea with many benefits to human health. TPS-5 was characterized as a pectin-type acidic polysaccharide. It has a backbone composed of → 2,4)- α- L-Rhap-(1) → 4)- α- D-GalAp-(1) →, with a branch composed of → 5)- α- L-Ara-(1 → 5,3)- α- L-Ara-(1 → 3)- β- D-Gal-(1 → 3,6)- β- D-Galp-(1) →. The in vitro biological activity evaluation illustrated that TPS-5 has free radical scavenging, ferric-ion-reducing, digestive enzyme inhibitory, and bile-salt-binding abilities. These results suggest that TPS-5 from Liupao tea has potential applications in functional foods or medicinal products.