LC-MS, NMR fingerprint of Potentilla argentea and Potentilla recta extracts and their in vitro biopharmaceutical assessment

Many Potentilla species are used as traditional drugs in several countries and also studied for their possible therapeutic properties. As part of our continuous effort to shed light on the biopharmaceutical potential of such plant species, this study was aimed to establish the phytochemical fingerprinting and to evaluate biopharmaceutical potential of methanol, ethyl acetate, and water extracts obtained from the aerial parts of Potentilla recta L. and P. argentea L. Combination of 1 dimension, 2 dimension-nuclear magnetic resonance as well as LC-DAD-ESI-MS and LC-APCI-MS allowed the identification of ellagitannins, flavonol glycosides, and triterpene constituents. To quantify different constituents in the extracts obtained with different solvents, the total contents in phenolics, flavonoids, saponins, and triterpenoid were evaluated. The antioxidant activity was assessed by the means of metal chelation, phosphomolybdenum, radical quenching (by 2,2-diphenyl-1-picrylhydrazyl [DPPH] and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)[ABTS]) and reduction ability (by cupric reducing antioxidant capacity [CUPRAC] and ferric reducing antioxidant power [FRAP]) assays. Phytochemical analysis showed similar composition of the tested methanol extracts. Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, α-amylase, and α-glucosidase were selected as target enzymes to detect enzyme inhibitory potentials of these extracts. The water extract of P. argentea (113.29 mg gallic acid equivalent/g extract) contained the highest phenolic amount while the methanol extract (519.70 mg quillaja equivalent /g extract) showed the highest saponin content. The water extract of both Potentilla species was the most potent ABTS scavenger as well as present the highest CUPRAC activity. The most potent inhibitory activity against AChE and BChE was observed for the ethyl acetate extracts of P. recta and P. argentea. The methanol extracts of P. recta (53.16 mmol acarbose equivalent [ACAE]/g extract) and P. argentea (45.68 mmol ACAE/g extract) were the most active inhibitors of α-glucosidase. Data collected from this study support the multiple therapeutic actions of P. recta and P. argentea and justify further pharmacological investigations for potential applications in the pharmaceutical industry.