Investigating the chemical profile of Rheum lhasaense and its main ingredient of piceatannol-3'-O-ß-D-glucopyranoside on ameliorating cognitive impairment.

Rheum lhasaense A. J. Li et P. K. Hsiao, a stout herb plant from the Polygonaceae, is a typical Tibetan folk herb with heat-clearing and detoxifying effects, but does not have the typical laxative effect compared with other rhubarb plants. Nevertheless, its chemical composition and pharmacological activities still lack in-depth research. The present study endeavored to analyze the possible phytochemical constituents in R. lhasaense and explore the main compound piceatannol-3'-O-ß-D-glucopyranoside (PG) effect on cognitive impairment and its underlying mechanism. The chemical profile of R. lhasaense discovered 46 compounds, including 27 stilbenoids and 13 gallotannins using UPLC-Q-TOF-MS/MS. The UPLC determined the contents of 6 main stilbenoids, among which the content of PG was the highest, up to 61.06 mg/g. Moreover, behavioral tests showed that PG (40 mg/kg and 160 mg/kg) administration markedly ameliorated memory impairments of scopolamine-induced mice. Biochemical parameters showed that PG treatment alleviated the levels of Ach, AchE, and inflammatory factors while elevating the levels of antioxidants in mice. In addition, network pharmacology was performed to reveal PG exert an mild cognitive impairment effect by participating in neurodegenerative disease pathways, proliferation and apoptosis-, and inflammation-related pathways. Eventually, the results of molecular docking and the qRT-PCR revealed that PG down-regulated the mRNA expressions of MMP3, MMP9 and BACE1 in cognitive impairment mice brain tissue. In conclusion, our results demonstrated that PG mitigated scopolamine-induced cognitive dysfunction in mice by targeting the BACE1-MMP3/9 pathway, and PG might be a promising mild AD drug candidate.

Purification of total flavonoids from Ginkgo biloba flowers with resin column chromatography and evaluation of antioxidant activities in vitro.

Purification of total flavonoids from Ginkgo biloba flowers (GBF) extracts were studied using six resins. Adsorption-desorption experiments indicated that polyamide resin is the most suitable resin. The optimal purification process of total flavonoids of GBF was as follows: a loading concentration of 5.85 mg/mL, a loading volume of 1 bed volume (BV), a loading flow rate of 2 BV/h, a water volume of 2.67 BV, and a desorption solution of 40% ethanol. Under these conditions, the maximum purity of total flavonoids was 37.1 ± 1.1%. The antioxidant activity of purified flavonoids was further evaluated in vitro. It showed that the 40% ethanol purified fraction (Fr. B) group had the strongest antioxidant activity of the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity concentration for 50% of maximal effect (EC50, 145.4 ± 13.8 µg/mL) and ferric reducing ability (2.5 ± 0.2 mM FeSO4 equivalent mg-1 Fr. B). In addition, at the concentration of 160 µg/mL, the Fr. B strikingly increased the viability rate of hydrogen peroxide stimulated PC-12 cells to normal levels (***p < 0.001). This method provides a basis for the application and development of GBF resources. It indicated that the purified GBF flavonoids can be used as a source of potential antioxidant.

Magnetically recoverable Fe3O4@polydopamine nanocomposite as an excellent co-catalyst for Fe3+ reduction in advanced oxidation processes.

Advanced oxidation processes are widely applied to removal of persistent toxic substances from wastewater by hydroxyl radicals (·OH), which is generated from hydrogen peroxide (H2O2) decomposition. However, their practical applications have been hampered by many strict conditions, such as iron sludge, rigid pH condition, large doses of hydrogen peroxide and Fe2+, etc. Herein, a magnetically recyclable Fe3O4@polydopamine (Fe3O4@PDA) core-shell nanocomposite was fabricated. As an excellent reducing agent, it can convert Fe3+ to Fe2+. Combined with the coordination of polydopamine and ferric ions, the production of iron sludge is inhibited. The minimum concentration of hydrogen peroxide (0.2 mmol/L and Fe2+ (0.18 mmol/L)) is 150-fold and 100-fold lower than that of previous reports, respectively. It also exhibits excellent degradation performance over a wide pH range from 3.0 to 9.0. Even after the tenth recycling, it still achieves over 99% degradation efficiency with the total organic carbon degradation rate of 80%, which is environmentally benign and has a large economic advantage. This discovery paves a way for extensive practical application of advanced oxidation processes, especially in environmental remediation.

Mikania micrantha genome provides insights into the molecular mechanism of rapid growth.

Mikania micrantha is one of the top 100 worst invasive species that can cause serious damage to natural ecosystems and substantial economic losses. Here, we present its 1.79 Gb chromosome-scale reference genome. Half of the genome is composed of long terminal repeat retrotransposons, 80% of which have been derived from a significant expansion in the past one million years. We identify a whole genome duplication event and recent segmental duplications, which may be responsible for its rapid environmental adaptation. Additionally, we show that M. micrantha achieves higher photosynthetic capacity by CO2 absorption at night to supplement the carbon fixation during the day, as well as enhanced stem photosynthesis efficiency. Furthermore, the metabolites of M. micrantha can increase the availability of nitrogen by enriching the microbes that participate in nitrogen cycling pathways. These findings collectively provide insights into the rapid growth and invasive adaptation.

[Wetting agent dosage screening for traditional Chinese medicine pellet based on torque rheological property].

With lubricant and bonding effect simultaneously, wetting agent has direct effect on properties of wet mass and extrudate, thus affecting the forming quality of pellets in extrusion-spheronization process. In this research, 25 representative kinds of traditional Chinese medicine(TCM) were selected as model drugs and 20%, 30% and 40% drug loading were set with MCC as their balling agent. The torque rheological curves were measured to get parameters such as maximum torque (Tmax) and corresponding water addition (WTmax) for these 75 raw materials by a mixer torque rheometer (MTR).The results showed that among 75 representative raw materials, 74 ones could be obtained for spherical pellets under the water addition of WTmax-2. corresponding to the second largest torque in torque rheological curve, suggesting that MTR could be used to select the optimal wetting agent dosage of TCM pellets. So the tedious and expensive pre-production work could be considerably reduced when TCM pellets were prepared.