Phytochemical profiling, biological activities, and in silico molecular docking studies of water hyacinth (Pontederia crassipes mart.) aerial part extracts

Water hyacinth (Pontederia crassipes Mart.) has received a growing attention for its valorization to convert it from a threat to an added value plant with a plethora of biological properties. This study investigates the bioactive phytochemicals and in vitro biological activities of several extracts of P. crassipes collected from Lake Tana, Ethiopia. The research also includes an in silico molecular docking analysis to support the findings.

The bioactive compounds were evaluated through preliminary phytochemical tests, LC MS/MS, and GC-MS analysis for chemical profiling. The antioxidant activity was performed by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), chelation iron, and FRAP assays. In vitro anti-inflammatory activities were evaluated by lipoxygenase inhibition, protease inhibition, and albumin denaturation assays. As results, the ethanol and water extracts revealed their richness in polyphenols and flavonoids evidenced by the phytochemical contents. GC-MS analysis of n-hexane extract revealed the identification of several phytosterols, where stigmasterol and β-sitosterol dominated the extract. LC-MS/MS analysis identified 34 compounds in the aerial parts of the ethanolic extract, predominantly comprising polyphenols as well as organic and phenolic acids. Ethanol and water extracts showed good antioxidant potential. Moreover, the hexane extract of the plant exhibited modest anti-inflammatory activity by the inhibition of lipoxygenase and protease. Furthermore, no cytotoxic effect was observed on WS1 and HaCaT cells at higher concentrations for the different extracts. The major identified compounds were further analyzed using in silico molecular docking studies to assess their binding affinity with enzymes such as lipoxygenase, ovalbumin, and Bovine Serum Albumin. The activity prediction suggest that these compounds possess anti-inflammatory properties. Additional validation through molecular dynamics (MD) simulations suggests that emodin-sulfate and stigmasterol could form stable complexes with lipoxygenase and Bovine Serum Albumin, respectively. Furthermore, the pharmacokinetic properties of these compounds were evaluated using SwissADME, highlighting their potential as promising drug candidates.

Thus, the findings of this study emphasized the potential use of P. crassipes biomass and its high value-added products in the pharmaceutical industry and medical research.