《食品工业科技》F5000论文展播：沙棘多糖清除自由基及抗脂质过氧化作用研究（2022年）

Objectives: In this paper, four kinds of liver homogenate in vitro models were established to simulate the human body environment, and VC was used as the positive control to compare with the sea buckthorn polysaccharide group. The changes of MDA content, the main degradation product of lipid peroxide ( LPO ), were observed to explore the free radical scavenging and anti-lipid peroxidation of sea buckthorn polysaccharide in vitro. In this paper, the in vitro model is used to simulate the in vivo environment, which can not only observe the reflection of the measured substance in the organism, but also clarify the detailed reaction mechanism of the substance in the body.

Methods: Seabuckthorn polysaccharide was extracted from pretreated seabuckthorn. The scavenging ability of seabuckthorn polysaccharide on DPPH free radical, hydroxyl radical ( OH · ) and superoxide anion (O2-·) free radical and the total reducing ability of seabuckthorn polysaccharide were determined by in vitro antioxidant activity method. The mice were sacrificed after fasting for 12 h. The liver was taken and rinsed repeatedly in 4 °C normal saline to remove blood, remove fat, and dry the surface with filter paper. After weighing and cutting, the homogenate was fully ground with a homogenizer under ice bath conditions, and normal saline was added to form 5 % liver homogenate. The liver homogenate was centrifuged at 4 °C and 3000 r / min for 10 min, and the supernatant was taken. The preparation of liver homogenate was completed at 4 °C. The spontaneous lipid peroxidation model of mouse liver homogenate in vitro, the lipid peroxidation model of mouse liver homogenate induced by CCl4 in vitro, the lipid peroxidation model of mouse liver homogenate induced by H2O2 in vitro, and the lipid peroxidation model of mouse liver induced by Fe2 + -VC in vitro were established by simulation. The TBA coloration method was used to observe the inhibitory effect of sea buckthorn polysaccharide on lipid peroxidation. The experimental data in this paper were expressed as mean ± standard deviation. SPSS 19.0 software was used for analysis. According to statistical analysis, t test was used to analyze the differences between groups. P < 0.05 was the significant standard. SigmaPlot 12.5 and Excel were used for plotting analysis.

Results:In a certain concentration range, seabuckthorn polysaccharide had scavenging ability to DPPH free radical, OH · free radical and O^2-·  free radical, and its IC₅₀ values were 1.55, 0.97 and 7.95 mg / mL, respectively. With the increase of seabuckthorn polysaccharide concentration, the scavenging rate of hydroxyl free radical increased, and its scavenging ability to hydroxyl free radical was lower than that of V_C in the concentration of 0.1~2 mg / mL. With the increase of the concentration of sea buckthorn polysaccharide, the scavenging rate of superoxide anion free radical increased. When the concentration was 1 ~ 6 mg / mL, the scavenging rate of superoxide anion free radical increased slowly. When the concentration was 6 ~ 8 mg / mL, the scavenging rate of superoxide anion free radical increased rapidly. When the concentration was 1 ~ 6 mg / mL, the scavenging ability of sea buckthorn polysaccharide on superoxide anion free radical was lower than that of V_C. With the increase of seabuckthorn polysaccharide concentration, the DPPH free radical scavenging rate increased. When the concentration was 1 ~ 3 mg / mL and 4 ~ 5 mg / mL, the scavenging ability of DPPH free radical increased rapidly. When the concentration was 3 ~ 4 mg / mL, the scavenging ability of DPPH free radical increased slowly. When the concentration of seabuckthorn polysaccharide was 1 ~ 4 mg / mL, the scavenging effect of DPPH free radical was lower than that of V_C. When the concentration was 5 mg / mL, the scavenging rate of DPPH free radical by seabuckthorn polysaccharide and V_C was 93.69 % and 95.28 %, respectively. With the increase of seabuckthorn polysaccharide concentration, the reducing ability gradually increased. When the concentration was 0 ~ 0.5 mg / mL, the reducing ability was not significantly different from that of V_C at the same concentration.When the concentration of seabuckthorn polysaccharide and V_C was 1 ~ 1.5 mg / mL, the growth rate of reducing ability of seabuckthorn polysaccharide was greater than that of V_C. When the concentration of seabuckthorn polysaccharide was 1.3 ~ 2 mg / mL, the reducing ability was greater than that of V_C at the same concentration.The absorbance values of seabuckthorn polysaccharide groups and V_C group at 532 nm were lower than those of the control group, indicating that the four liver homogenate models were successfully established in vitro. Seabuckthorn polysaccharide had inhibitory effects on spontaneous lipid peroxidation of mouse liver homogenate and liver lipid peroxidation induced by CCl₄, H₂O₂ and Fe²⁺-V_C. The IC₅₀ values were 1.10,1.59,9.13 and 1.39 mg / mL, respectively.

Conclusion: Seabuckthorn polysaccharide has certain scavenging ability on DPPH free radical, OH · free radical and O^2-· free radical. Seabuckthorn polysaccharide has strong scavenging ability on DPPH free radical and OH · free radical, and weak scavenging ability on O^2-· free radical. When the concentration of sea buckthorn polysaccharide was 2 mg / mL, the reduction ability was slightly higher than that of V_C at the same concentration. It shows that seabuckthorn polysaccharide has good antioxidant activity. Four kinds of liver homogenate in vitro models were established to simulate the human body environment. V_C was used as a positive control to compare with the seabuckthorn polysaccharide group. Both seabuckthorn polysaccharide and V_C could inhibit the formation of lipid peroxides in mouse liver homogenate. It shows that seabuckthorn polysaccharide has the function of anti-lipid peroxidation.