[Improvement effect of Lycium barbarum polysaccharide on the intestinal flora of pregnant rats and their offspring under chronic stress].

Objective: To understand the improvement effect of Lycium barbarum polysaccharide (LBP) on the intestinal flora of mother mice during pregnancy and their offspring who experienced chronic stress, and provide new ideas for improving the effect of stress on the intestinal tract. Methods: From July to October 2019, 24 SPF-grade female SD rats were selected and divided into control group, stress group, and stress+LBP group, with 8 rats in each group. A chronic unpredictable mild stimulation model during pregnancy was established (21 days) , and 40 mg/kg LBP solution was administered by gavage on the 8th day of stress. Venous blood from the medial canthus of the female mice was collected on the 1st day before stress and on the 1st, 7th, 14th and 21st days, respectively. Cortisol was measured and corticosterone concentration was calculated. The fresh feces of famale mice after stress and 20-day postnatal offspring mice were collected, and Illumina Miseq sequencing technology, alpha diversity and community composition were used to analyze the diversity and structure of intestinal flora. Results: On the 7th and 14th days of stress, the plasma corticosterone concentration of female mice in the stress group and stress+LBP group was higher than that in the control group (P<0.05) . In the Alpha diversity of female mice, the Ace index of the stress group was lower than that of the control group (P<0.05) . The analysis of intestinal flora structure showed that at the species level, the proportions of Lachnospiraceae and Lactobacillus in the stress+LBP group were higher than those in the stress group and control group. At the order level, the proportion of Clostridiales in the stress+LBP group was higher than that in the stress group and lower than that in the control group, while the proportion of Lactobacillales was higher than that in the stress group and control group. In the Alpha diversity of the offspring group, the Shannon index, Ace index and Chao index of the stress+LBP offspring group were higher than those of the stress offspring group (P<0.05) . The proportion of Lactobacillus in the stress+LBP offspring group was higher than that in the control offspring group and stress offspring group, and the proportions of Lachnospiraceae and Ruminococcaceae in the stress+LBP offspring group were higher than those in the stress offspring group, the proportion of Bacteroidales in the stress+LBP offspring group was lower than that in the stress offspring group, and the proportion of Clostridiales in the stress+LBP offspring group was higher than that in the stress and control offspring groups. Conclusion: The intervention of LBP may improve the changes in the intestinal flora diversity, abundance and flora structure of mother mice and offspring caused by pregnancy stress, thereby maintaining the balance of intestinal flora.

Effect of bio-treatment on the lipophilic and hydrophilic extractives of wheat straw.

Wheat straw, an important papermaking raw material in China, was treated with a white-rot fungus of Phanerochaete chrysosporium ME446, and the lipophilic and hydrophilic extractives from the control and bio-treated samples were analyzed by GC and GC-MS. Bio-treatment of wheat straw could alter the chemical composition of both the lipophylic and hydrophilic extractives. Sugars and phenolic substances such as coniferyl alcohol, 4-hydroxycinnamic acid, 1-guaiacylglycerol and ferulic acid were substantially degraded or consumed by the fungus. More lipophilic substances such as wax, glycerides and steryl esters were degraded into the corresponding components, resulting in much higher concentrations of fatty acids and sterols in the bio-treated samples. Obviously, the bio-treatment of wheat straw was of benefit to pitch control in pulping and papermaking processes, in the view of degradation of the more lipophilic substances. In addition, the bio-treatment could increase the lignin concentration in hot-water extractives of wheat straw.