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.

Synthesis, characterization, in vitro antioxidant and hypoglycemic activities of selenium nanoparticles decorated with polysaccharides of Gracilaria lemaneiformis.

Under a simple redox system of selenite and ascorbic acid, we used Gracilaria lemaneiformis polysaccharides (GLPs) as a stabilizer and dispersing agent to generate well-dispersed and stable selenium nanoparticles (SeNPs). The size, stability, morphology and physicochemical properties of GLPs-SeNPs were characterized by dynamic light scattering (DLS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Ultraviolet-visible spectroscopy (UV-vis), Fourier transform infrared (FT-IR) spectra, energy dispersive X-ray (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Thermogravimetric (TG). The results showed that orange-red, amorphous, zero-valent and spherical GLPs-SeNPs with mean diameter of approximately 92.5 nm were successfully prepared, which exhibited good storage stability at 4 °C and remaining highly stable at different ion strengths and pH. The 2,2-diphenyl-1-pycrylhydrazyl (DPPH), 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) and superoxide anion radical (O2•-) radical scavenging ability of GLPs-SeNPs were higher than those of bare SeNPs, GLPs and sodium selenite (Na2SeO3), and could reach 103.41%, 94.23%, 86% at a concentration of 1.5 mg/mL, respectively. Besides, GLPs-SeNPs also showed higher inhibitory effects on α-amylase and α-glucosidase. In vitro cytotoxicity assay and hemolysis activity examinations indicated that GLPs-SeNPs have excellent biocompatibility. Therefore, the GLPs-SeNPs might be used as a potential antioxidant agent and antidiabetic agent for food and medical applications.

Synthesis and evaluation of Grateloupia Livida polysaccharides-functionalized selenium nanoparticles.

Grateloupia Livida polysaccharides-functionalized selenium nanoparticles (GLP-SeNPs) have been successfully prepared in a simple redox system of sodium selenite and ascorbic acid. The size, morphology, structure, stability and thermal behavior were analyzed by various characterization methods. These results showed that, GLP-SeNPs (particle size of 115.54 nm) prepared in optimal synthesis conditions (temperature of 45 °C, reaction time of 3 h, GLP concentration of 1.0 mg/mL and ascorbic acid concentration of 0.04 M) obtained by orthogonal experiments were uniform spherical and could be stable for 30 days at 4 °C. GLP-SeNPs exhibited significant scavenging ability on DPPH, ABTS, hydroxyl radical and superoxide anion radical when compared to GLP and Na2SeO3. GLP-SeNPs showed selective cytotoxicity toward various human cancer cells, but not normal cells. Besides, GLP-SeNPs exhibited low oral acute toxicity. Taken together, GLP-SeNPs might be used as potential diet nutritional supplement or anticancer agent.

Preparation and antioxidant activity of selenium nanoparticles decorated by polysaccharides from Sargassum fusiforme.

In this study, the response surface method was employed to optimize the extraction conditions of the ultrasonic-assisted extraction of Sargassum fusiforme polysaccharides (SFPS). The effects of four independent variables (hot water extraction time, ultrasonic time, ultrasonic power, and material-to-liquid ratio) on the extraction rate of SFPS were tested. In addition, the SFPS functionalized nanoselenium (SFPS-SeNPs) was prepared by chemical reduction method, whose characterization and in vitro antioxidant activity were investigated. The results showed that the yield of the crude SFPS was 25.8% at the optimal conditions of material-to-liquid ratio 1:50 (w/v), ultrasonic power 200 W, ultrasonic time 15 min, and water bath time 130 min. A series of characterization experiments showed that the SFPS-SeNPs performed higher dispersion and stability than naked SeNPs. Furthermore, the in vitro antioxidant activity assay indicated that SFPS functioned as a modifier improved the free radical scavenging activity of SeNPs significantly. In conclusion, this study provided a method to extract SFPS as a carrier for SeNPs, and SFPS-SeNPs could not only improve the stability of SeNPs, but also exerted the biological activities of SFPS. PRACTICAL APPLICATION: This research provided new ideas for the application of SFPS and the development of nanoselenium preparation carriers.

Optimization of extraction flavonoids from Exocarpium Citri Grandis and evaluation its hypoglycemic and hypolipidemic activities.

ETHNOPHARMACOLOGICAL RELEVANCE: Exocarpium Citri Grandis (ECG; Huajuhong in Chinese) is a precious traditional Chinese medicine with a history of hundreds of years in China. It has been demonstrated to possess numerous pharmacological properties, including antitussive, expectorant, anti-inflammatory, hypoglycemic, and hypolipidemic. However, no in-depth report exists on the hypoglycemic and hypolipidemic properties of ECG. AIM OF THE STUDY: This study aimed to evaluate the hypoglycemic and hypolipidemic properties of ECG flavonoids extract in vitro and in vivo so as to lay the foundation for further researches in this field. MATERIALS AND METHODS: Total flavonoids (TF) and naringin were separately extracted from ECG, and the components of TF were identified by HPLC-MS. The antioxidant capacities of TF and naringin were determined by 2,2,1-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging tests, and digestive enzymes activity inhibition assays in vitro in order to evaluate their hypoglycemic properties. Furthermore, diabetic mice experiments were performed to assess the hypoglycemic and hypolipidemic properties of TF and naringin in vivo. RESULTS: Five compounds were identified from TF, including naringin, rhoifolin, poncirin, bergaptol, and naringenin. The half maximal inhibitory concentration (IC50) of TF and naringin to DPPH-free radicals were 0.269 and 1.946 mg/mL, respectively. TF and naringin demonstrated a certain inhibitory effect on α-glucosidase and a weaker inhibitory effect on α-amylase. The results of animal experiments showed that TF and naringin had no significant effect on the blood glucose levels, but they could lead to significant (p < 0.05 or p < 0.01) increase in the serum insulin level and high-density lipoprotein cholesterol (HDL-C) levels with concomitant reduction in the total cholesterol (TC), total triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) levels in diabetic mice. In addition, TF and naringin could reduce the liver index of diabetic mice (p < 0.01) and reduce the kidney index at low doses (p < 0.05). CONCLUSIONS: Our study revealed that the hypoglycemic and hypolipidemic activities of TF is mainly derived from naringin, and other active ingredients in TF also have the effects of alleviating oxidative stress, inhibiting digestive enzyme activity and reducing blood lipids. Our results thus provide a scientific basis for the application of ECG in antidiabetic treatment.

Antidiabetic and Lipid-Lowering Effects of the Polyphenol Extracts from the Leaves of Clausena lansium (Lour.) Skeels on Streptozotocin-Induced Type 2 Diabetic Rats.

Clausena lansium (Lour.) Skeels (Wampee) is widely grown in China and considered as a healthy fruit. Its leaves are also considered as traditional herbs. This study analyzed polyphenol compounds in polyphenol extracts of the leaves C. lansium (lour.) Skeels (PEL) and investigated the protective effect of PEL against hyperglycemia and hyperlipidemia in T2DM rats. The result showed that PEL is composed mainly of gallic acid, chlorogenic acid, coffee acid, ferulic acid, and rutin. PEL could obviously relieve some symptoms of T2DM rats, including emaciation, hyperhidrosis, polyphagia, diuresis, liver swelling, kidney, and pancreas hypertrophy, as well as reduce fasting blood glucose. Moreover, the supplementation of PEL significantly ameliorated lipids disorder and protected liver in T2DM rats, including fat accumulation, improvement of lipid distribution and hepatocyte protection. These results indicate that the Oral of PEL have potential effects of against hyperglycemia and hyperlipidemia in diabetic disorders. PRACTICAL APPLICATION: The leaves Clausena lansium (lour.) Skeels is rich in polyphenol and other ingredients. In this research, the preliminary study shows that PEL can reduce fasting blood glucose and improve lipids disorder in rats, which will bring to diabetic patients a way to improve the disease and enhance the quality of life. The PEL therefore can be used for the production of pharmaceutical raw materials and the design of novel functional foods by simple conversion.

Optimization of Process Parameters and Kinetic Model of Enzymatic Extraction of Polyphenols from Lonicerae Flos.

OBJECTIVE: To optimize and verify the cellulase extraction of polyphenols from honeysuckle and provide a reference for enzymatic extracting polyphenols from honeysuckle. MATERIALS AND METHODS: The uniform design was used According to Fick's first law and kinetic model, fitting analysis of the dynamic process of enzymatic extracting polyphenols was conducted. RESULTS: The optimum enzymatic extraction parameters for polyphenols from honeysuckle are found to be 80% (v/v) of alcohol, 35:1 (mL/g) of liquid-solid ratio, 80°C of extraction temperature, 8.5 of pH, 6.0 mg of enzyme levels, and 130 min of extraction time. Under the optimal conditions, the extraction rate of polyphenols was 3.03%. The kinetic experiments indicated kinetic equation had a good linear relationship with t even under the conditions of different levels of enzyme and temperature, which means fitting curve tallies well with the experimental values. CONCLUSION: The results of quantification showed that the results provide a reference for enzymatic extracting polyphenols from honeysuckle. SUMMARY: Lonicerae flos (Lonicera japonica Thunb.) is a material of traditional Chinese medicine and healthy drinks, of which active compounds mainly is polyphenols. At present, plant polyphenols are the hotspots centents of food, cosmetic and medicine, because it has strong bioactivity. Several traditional methods are available for the extraction of plant polyphenols including impregnation, solvent extraction, ultrasonic extraction, hot-water extraction, alkaline dilute alcohol or alkaline water extraction, microwave extraction and Supercritical CO2 extraction. But now, an increasing number of research on using cellulase to extract active ingredients from plants. Enzymatic method is widely used for enzyme have excellent properties of high reaction efficiency and specificity, moderate reaction conditions, shorter extraction time and easier to control, less damage to the active ingredient. At present, the enzymatic extraction of polyphenols from honeysuckle and dynamic had not been reported. In this study, using cellulase to extract polyphenols from honeysuckle is first applied. Moreover, uniform design was used to optimize process and kinetic model of extraction was established to analyze the characteristics of enzymatic extraction, in order to improve the yield of polyphenols from honeysuckle and make maximum use of Lonicerae flos, which provide references for industrial production.

[Mathematical kinetic model of dual-frequency ultrasound assisted extraction of effective components traditional Chinese medicine].

OBJECTIVE: To establish the mathematical kinetic model of the components extracted from the Salvia miltiorrhiza. METHOD: In the conditions of ultrasound extracting the course of traditional Chinese medicine, the role of ultrasound intensity is large enough, the proliferation of boundary layer can be infinitesimal, as well as the solute upon the surface of medicine quickly into the main solution, we can assume that the whole process of extraction from the control of proliferation. A mathematical model of dual-frequency ultrasound extraction kinetics based on Fick's second diffusion law was established for traditional Chinese medicine. Based on material size and solid/liquid ratio significant factors. RESULT: We adopt Origin software to carry out a mathematics simulation, the result showed: simulation graphics and experiment value are very fitting. CONCLUSION: This proves that S. miltiorrhiza extraction course accords with ordinary extraction dynamics equation at the dual-frequency ultrasound.