Optimization of ultrasound extraction of Tribulus terrestris L. leaves saponins and their HPLC-DAD-ESI-MSn profiling, anti-inflammatory activity and mechanism in vitro and in vivo

J Ethnopharmacol. 2021 Oct 5:278:114225. doi: 10.1016/j.jep.2021.114225. Epub 2021 May 24.

Abstract

Ethnopharmacological relevance: Tribulus terrestris L., as an annual herb plant from Zygophyllaceae, exhibits many biological activities, and its main chemical constituents are saponins. However, the extraction process, chemical compositions, anti-inflammatory effect and mechanism of total saponins from Tribulus terrestris L. leaves are still unclear.

Aim of the study: The present study extensively evaluated the extraction process, major components, anti-inflammatory action and mechanism of Tribulus terrestris L. leaves saponins.

Materials and methods: The ultrasonic extraction and response surface methods were adopted for optimization of extraction technology of total saponins from Tribulus terrestris L. leaves, and its compositions were detected with LC-MSn method. The anti-inflammatory activity of total saponins was studied by lipopolysaccharide induced RAW 264.7 cells and acute lung injury mice models.

Results: The ultrasonic extraction parameters of saponins fraction, including ethanol concentration 30%, extraction time 55 min, ratio of solvent to material 35:1 ml/g and extraction temperature 46 °C, were screened by response surface method with the extracting rate 5.49%, and thirty compositions were detected with LC-MSn method. Moreover, saponins fraction can play a stronger anti-inflammatory effect by reducing the phagocytic activity and pulmonary edema, and protection of morphology of RAW 264.7 cells and lung tissues, and decreasing the content of NO and TNF-α. Moreover, it was revealed that total saponins extract can exert the anti-inflammatory action by the inhibition of the activation of the TLR4-TRAF6-NF-κB signalling pathway.

Conclusion: These studies imply that Tribulus terrestris L. leaves saponins may be an important anti-inflammatory drug in clinic.

Keywords: Anti-inflammatory action; Effective constituents; Mechanisms; Saponins; Tribulus terrestris L. leaves.

MeSH terms

  • Acute Lung Injury / drug therapy
  • Animals
  • Anti-Inflammatory Agents / chemistry
  • Anti-Inflammatory Agents / isolation & purification
  • Anti-Inflammatory Agents / pharmacology*
  • Chromatography, High Pressure Liquid
  • Disease Models, Animal
  • Lipopolysaccharides
  • Male
  • Mice
  • Plant Extracts / analysis
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Plant Leaves
  • RAW 264.7 Cells
  • Saponins / chemistry
  • Saponins / isolation & purification
  • Saponins / pharmacology*
  • Spectrometry, Mass, Electrospray Ionization
  • Tribulus / chemistry
  • Ultrasonics

Substances

  • Anti-Inflammatory Agents
  • Lipopolysaccharides
  • Plant Extracts
  • Saponins
  • Tribulus extract