Isolation and Evaluation of Anti-Alzheimer Compounds from P. hydropiper

In the search for new anti-Alzheimer’s and neuroprotective drugs from Polygonacae, P. hydropiper L. was identified, collected and processed for fractionation as previously reported from our laboratory (Ayaz et al., 2014b (link), 2016 (link)). A plant specimen was deposited with voucher no H.UOM.BG.107 at the herbarium of the University of Malakand, Chakdara, Dir (L), KP, Pakistan. Solvent based fractions and saponins were initially subjected to in vitro anti-Alzheimer’s studies. The solvent fractions, especially chloroform and ethyl acetate were selected for the isolation of pure compounds due to their prominent activities in preliminary assays. Several compounds were isolated using gravity column chromatography eluting with n-haxane and ethyl acetate. The purified compounds were rotary evaporated to remove any remaining solvent. Initially, ¹H NMR spectra was obtained to reveal the chemical structure by comparing the spectra with those reported in the literature. The ¹³C NMR spectra were used to ascertain the carbon skeleton of the compounds. The spectral data was supplemented by using mass spectrometry to confirm the structures. Among the isolated compounds, β-sitosterol was most active in the preliminary analysis and was evaluated in detail (Figure 1).