Withania somnifera, Angelica sinensis, Glycyrrhiza glabra, and Simmondsia chinensis were acquired from the Egyptian market, profiled for their chemical constituents, screened for the in-vitro MAO-B inhibitory activity and evaluated for the total phenolic content. Thirty compounds were characterized in the selected herbs using HPLC-MS/MS. In-vitro MAO-B inhibitory activity and total phenolic content of the acquired herbs were compared with those of a prepared herbal formula consisting of a mixture of equal amounts of the four mentioned herbs. The most potent MAO-B inhibitory activity was exerted by the methanol extract of the prepared formula (IC50 of 712.19 ± 13.90 ng/mL) compared to selegiline (IC50 of 581.69 ± 11.35 ng/mL). The highest value of the total phenolic content was shown by Angelica sinensis methanolic extract (76.15 ± 0.1 mg/g) followed by Glycyrrhiza glabra methanolic extract (65.74 ± 0.1 mg/g), then the mixture's methanolic extract of the four herbs (37.04 ± 0.1 mg/g).
Keywords: Angelica; Ashwagandha; HPLC-MS/MS; MAO-B; Parkinson’s disease; jojoba; licorice.