Effects of Tianxiang capsule on neurotransmitters and hormone level in rats with motion sickness / 国际中医中药杂志

Objective To investigate the effects of Tianxiang capsule on Neurotransmitters and Hormone Level of rats with motion sickness. Methods Male SD rats were randomly divided into six groups, including blank control group, model control group, positive drug control group, low-dose, mid-dose and high-dose Tianxiang capsule groups with the method of random digital table, and every group had 10 mice. Except the normal group, the rats in the other groups were intragastrically pre-administered for 1 hour, and the low, medium and high doses of Tianxiang capsule were 0.91, 1.82, 3.64 g/kg, the positive drug control group was given scopolamine 1 mg/kg, and then the rat motion sickness model was induced by a rotary stimulation device. After the modeling, the feces, urine, standing hair, trembling were immediately observed and recorded, and the halo response index of the rats was calculated. The blood from the heart puncture was taken and the vestibular nucleus were put on the ice. Then, the content of histamine (HIS) in the vestibular nucleus and plasma was detected by ELISA. The expression of plasma cortisol (Cort) and arginine vasopressin (AVP) were measured by radioimmunoassay. Results Compared with the model control group, the motion sickness index of rats with low, medium and high doses of Tianxiang capsule (6.56 ± 2.16, 6.10 ± 1.35, 4.46 ± 2.50 vs. 8.90 ± 2.61) significantly decreased (P<0.05 or P<0.01). The HIS content in the vestibular nucleus (12.70 ± 3.86 μg/L, 11.45 ± 1.57 μg/L, 10.02 ± 1.30 μg/L vs. 17.50 ± 4.82 μg/L) significantly decreased (P<0.05 or P<0.01). The plasma content of HIS (4.24 ± 1.75 μg/L vs. 7.69 ± 3.06 μg/L), Cort (286.90 ± 8.72 ng/ml vs. 329.26 ± 29.04 ng/ml) and AVP (16.54 ± 2.48 pg/ml vs. 22.35 ± 3.08 pg/ml) in the high doses of Tianxiang capsule significantly decreased (P<0.05 or P<0.01). Conclusions The Tianxiang capsule could effectively reduce the motion sickness index of rats with motion sicknes, which might be related to the down-regulation of HIS in Vestibule Nucleus and HIS, Cort and AVP in plasma.

Identification and characterization of six glycosyltransferases involved in the biosynthesis of a new bacterial exopolysaccharide in Paenibacillus elgii.

Paenibacillus elgii B69 produces a new xylose-containing exopolysaccharide (EPS) that effectively removes the pollutants from wastewater through flocculation. However, information about the biosynthesis of this EPS is limited. In this study, sequence analysis showed six putative glycosyltransferases (GTs) genes in polysaccharide gene clusters involved in glycosidic linkages of repeating units. Each gene was deleted and phenotypes were examined to understand the functions of these genes. Two of the genes were deleted successfully to encode a priming glucose GT and a side-chain xylose GT, but other genes were unsuccessfully deleted because of the accumulation of toxic intermediate products. The six genes were cloned and expressed in Escherichia coli, and the corresponding enzymes were purified. The activity of GTs was analyzed through mass spectrometry by using the purified membrane fraction as a lipid carrier receptor after a hexasaccharide repeated unit was reconstructed in vitro. The specificities of six different GTs and the building order of the hexasaccharide were characterized. This study provided a basis for future research on the biosynthetic pathway of EPS in Paenibacillus or other genera.

Progress in antimicrobial substances of endophytes / 生物工程学报

Isolation and characterization of metabolites produced by endophytes are significant ways to search for novel natural active substances, proving that the endophytes are the unique resources of newer and more effective compounds. Many new compounds with antimicrobial activity from different endophytes have been isolated so far. These new compounds provide alternatives to fight against multi-drug resistance of microorganisms. This review outlined the major achievements and latest developments of endophytes, including the diversity of endophytes and antimicrobial activity of endophytes, as well as its development in China.