Zhenzhen Gao

Optimization of selenylation conditions for lycium barbarum polysaccharide based on antioxidant activity.

Lycium barbarum polysaccharide (LBP) was modified by HNO3-Na2SeO3 method according to L9(3(4)) orthogonal design to obtain nine selenizing LBPs (sLBPs), sLBP1-sLBP9. Their antioxidant activities in vitro were compared by free radical-scavenging test. sLBP6, sLBP8 and sLBP9 presented stronger activity. In vivo test, 14-day-old chickens were injected respectively with sLBP6, sLBP8 and sLBP9 taking LBP as control, and serum GSH-Px and SOD activities and MDA content were determined. The results showed that three sLBPs could significantly enhance GSH-Px and SOD activities and decrease MDA content. The actions of sLBPs were significantly stronger than that of unmodified LBP. These results indicated that selenylation modification could significantly enhance the antioxidant activities of LBP, sLBP6 possessed the best efficacy and could be exploited into an antioxidant. The optimal modification conditions were 400mg of sodium selenite for 500 mg of LBP, reaction temperature of 70 °C and reaction time of 6h.

Effect of selenylation modification on immune-enhancing activity of Atractylodes macrocephala polysaccharide

The Atractylodes macrocephala polysaccharide (AMP) was extracted purified and modified in selenylation by Nitric acid-sodium selenite method to get nine selenizing AMPs (sAMPs), sAMP(1)-sAMP(9). In vitro test their effects on chicken peripheral lymphocyte proliferation were determined by MTT assay. The results showed that nine sAMPs and AMP at five concentrations could significantly promote lymphocyte proliferation, the actions in six sAMPs were significantly stronger than that in AMP, and in sAMP(9) was the strongest. In vivo test, 14-day-old chickens vaccinated with ND vaccine were injected respectively with sAMP(9) and AMP, the peripheral lymphocytes proliferation, serum antibody titer, IFN-γ, IL-2 and IL-6 contents were determined. The results displayed that the sAMP could significantly promote lymphocyte proliferation and elevate the antibody titers and content of IFN-γ, IL-2 and IL-6 in comparison with unmodified AMP. These results indicate that selenylation modification can significantly enhance the immune-enhancing activity of AMP.

Optimization on conditions of Lycium barbarum polysaccharides liposome by RSM and its effects on the peritoneal macrophages function

The purpose of this study was to optimize the preparation conditions of Lycium barbarum polysaccharides liposome (LBPL) by response surface methodology (RSM) and to investigate the effect of LBPL activating function of peritoneal macrophages. LBPL was prepared using the reverse-phase evaporation method. The optimal preparation conditions of LBPL by RSM were as follows: the ratio of lipid to drug (w/w) of 25:1, the ultrasound time of 14 min and the ratio of soybean phospholipids to cholesterol (w/w) of 2.4:1. Under these conditions, the experimental encapsulation efficiency of LBPL was 86.37±0.63%, which was close to the predicted value. These indicated that LBPL with high entrapping efficiency and small particle size could be prepared by the reverse-phase evaporation method, which is applied easily. Furthermore, macrophages are the key players in the innate immune system. LBPL could effectively enhance peritoneal macrophages phagocytosis and resulted in inducing NO (nitric oxide) production in mouse peritoneal macrophages.

Selenylation modification can enhance immune-enhancing activity of Chinese angelica polysaccharide.

On the basis of previous test that selenizing Chinese angelica polysaccharides (sCAPs) with stronger immune-enhancing activity in vitro were picked out, the immune-enhancing activity in vivo of three sCAPs, sCAP2, sCAP6 and sCAP8, at high and low dosage were compared taking the unmodified Chinese angelica polysaccharide (CAP) as control by determination of peripheral lymphocyte proliferation, serum antibody titer, IFN-γ and IL-6 contents in chicken vaccinated with Newcastle Disease vaccine. The results showed that three sCAPs at suitable dosage could significantly promote lymphocyte proliferation, enhance serum antibody titer, IFN-γ and IL-6 contents as compared with unmodified CAP, sCAP2 at low dosage possessed the strongest action. These results indicated that selenylation modification could significantly enhance the immune-enhancing activity of CAP, sCAP2 possessed the best efficacy and would be as a component drug of new-type immunoenhancer.

Optimization of selenylation modification for garlic polysaccharide based on immune-enhancing activity.

Garlic polysaccharide (GPS) was modified in selenylation respectively by nitric acid-sodium selenite (NA-SS), glacial acetic acid-selenous acid (GA-SA), glacial acetic acid-sodium selenite (GA-SS) and selenium oxychloride (SOC) methods each under nine modification conditions of L9(3(4)) orthogonal design and each to obtain nine selenizing GPSs (sGPSs). Their structures were identified, yields and selenium contents were determined, selenium yields were calculated, and the immune-enhancing activities of four sGPSs with higher selenium yields were compared taking unmodified GPS as control. The results showed that among four methods the selenylation efficiency of NA-SS method were the highest, the activity of sGPS5 was the strongest and significantly stronger than that of unmodified GPS. This indicates that selenylation modification can significantly enhance the immune-enhancing activity of GPS, NA-SS method is the best method and the optimal conditions are 0.8:1 weight ratio of sodium selenite to GPS, reaction temperature of 70 °C and reaction time of 10h.

The comparison of antioxidative and hepatoprotective activities of Codonopsis pilosula polysaccharide (CP) and sulfated CP

Codonopsis pilosula polysaccharide (CP) was extracted, purified and modified by chlorosulfonic acid-pyridine method to obtain a sulfated CP (sCP). Their antioxidative activities in vitro were compared through the free radical-scavenging test. The results demonstrated that the scavenging capabilities of sCP were significantly stronger than those of CP. In vivo test, the mice hepatic injury model was prepared by BCG/LPS method, then administrated respectively with sCP and CP at three dosages, the biochemical indexes in serum, antioxidative indexes in liver homogenate and histopathological change in liver of the mice were compared. The results showed that in high (200mg/kg) and middle (150mg/kg) dosages of sCP groups, the contents of ALT, AST and TNF-α in serum and MDA in liver homogenate were significantly lower than those in the model group and numerically lower than those in the CP groups, the activities of SOD and GSH-Px in liver homogenate were significantly higher than those in the model group and numerically higher than those in the CP groups. In the model group there were obvious pathological changes in the liver, while in the sCP groups were near normal. These results indicate that sCP and CP possess antioxidative activity in vitro and in vivo, the activity of sCP is stronger than that of CP and sulfation modification can enhance the antioxidative and hepatoprotective activities of Codonopsis pilosula polysaccharide.

Effects of Selenylation Modification on Immune-Enhancing Activity of Garlic Polysaccharide

The garlic polysaccharide was modified by HNO3-Na2SeO3 method according to orthogonal design L9(34) to obtain nine selenizing garlic polysaccharides, sGPS1-sGPS9. Their effects on chicken peripheral lymphocytes proliferation in vitro were compared by MTT assay. The results showed that sGPSs could significantly promote lymphocytes proliferation, sGPS3, sGPS5 and sGPS6 presented stronger efficacy. In vivo experiment, 14-day-old chickens were injected respectively with sGPS3, sGPS5 and sGPS6 when they were vaccinated with ND vaccine taking unmodified GPS as control. The results showed that three sGPSs could significantly promote lymphocyte proliferation, enhance serum antibody titer, IFN-γ and IL-2 contents. These results indicated that selenylation modification could significantly enhance the immune-enhancing activity of GPS, sGPS6 possessed the best efficacy and could be as a candidate drug of immunoenhancer. Its optimal modification conditions were 400 mg of sodium selenite for 500 mg of GPS, reaction temperature of 70°C and reaction time of 6 h.

Modification of lily polysaccharide by selenylation and the immune-enhancing activity.

Lily polysaccharide (LP) was extracted, purified and selenizingly modified by HNO3-Na2SeO3 method according to L9(3(4)) orthogonal design. Nine selenizing LPs, sLP1-sLP9, were obtained and their immune-enhancing activities were compared taking unmodified LP as control. The results in vitro test showed that sLP6 presented the strongest activity in promoting lymphocytes proliferation in single and synergetic with PHA, and the relative expression level of IL-2, IL-6 and IFN-γ mRNA of chicken peripheral lymphocytes. The results in vivo test showed that sLP6 could promote lymphocytes proliferation and enhance the serum antibody titers and serum IL-2, IL-6, IFN-γ contents more significantly than LP in chickens vaccinated with Newcastle Disease (ND) vaccine. These results indicate that polysaccharide selenizing can significantly enhance the immune-enhancing activity of LP and the optimal modification conditions are 400 mg of Na2SeO3 per 500 mg of LP, the reaction temperature of 70 °C and the reaction time of 6 h.

Effects of Selenylation Modification on Antioxidative Activities of Schisandra chinensis Polysaccharide.

The selenylation modification of Schisandra chinensis polysaccharide (SCP) was conducted by the HNO3–Na2SeO3 method respectively under nine conditions according to L9(34) orthogonal design. Nine selenizing SCPs, sSCP1–sSCP9, were obtained, and their antioxidant activities were compared. In vitro test, the free radical-scavenging rates of nine sSCPs were determined for DPPH., .OH and ABTS+. sSCP1 presented the most significant effect, and could inhibit the nonenzymatic protein glycation. In vivo test, 14-day-old chickens were injected respectively with sSCP1 and SCP, the serum contents of CAT, SOD and MDA were determined. The result showed that as compared with the SCP group, the SOD and CAT activities were significantly or numerically raised and MDA content was significantly or numerically lowered in the sSCP1 group. These results indicate that selenylation modification can significantly enhance the antioxidant and antiglycative activity of SCP in vitro or in vivo. sSCP1 possesses the best efficacy and its modification conditions can be as optimal modification conditions that were 200 mg of Na2SeO3 for 500 mg of SCP, reaction temperature of 50°C and reaction time of 6 h.

Development of liposomal Ganoderma lucidum polysaccharide: Formulation optimization and evaluation of its immunological activity

The aim of this study was to investigate the optimizing preparation conditions of Ganoderma lucidum polysaccharide liposome (GLPL) with response surface methodology (RSM) and the immunological enhancement activity of GLPL. The immunological enhancement activity of GLPL on splenocyte proliferation was measured. The optimum formulation of GLPL, in which the ratio of soybean phospholipid to cholesterol(w/w) of 11:1, the ratio of soybean phospholipid to tween-80 (w/w) of 10.5:1 and ultrasonic time(min) of 11, had higher entrapment efficiency (EE) of 71.43±0.49% with spherical shape and uniform sizes. In addition, GLPL could significantly promote splenocyte proliferation singly or synergistically with PHA and LPS. That indicated that the immunological enhancement of Ganoderma lucidum polysaccharide (GLP) was significantly enhanced after encapsulation with the liposome.