Agilent 6320

All spectral data were obtained on various instruments. The Buchi apparatus model B-545 was used to record the melting point and was uncorrected. Optical rotations were taken on the PerkinElmer model 341 LC polarimeter (Perkin-Elmer Inc, Massachusetts, MA, USA). The IR and UV spectra were measured on the JASCO 320-A and a Hitachi-UV-3200 spectrophotometers (Kyoto, Japan), respectively. The NMR spectral analyses were obtained by the Bruker Avance DRX 700 MHz spectrometer (Rheinstetten, Germany), in either CDCl₃ or CD₃OD. FAB-MS and EI-MS were determined by using the JEOL SX 102/DA-6000 and Agilent 6320 ion trap mass spectrometers (ThermoFinnigan, Bremen, Germany), respectively. Column and gel permeation chromatographic separations were performed on silica gel 60 (Merck, 0.04–0.063 mm, Darmstaddt, Germany) and sephadex LH-20, respectively. TLC analyses were carried on pre-coated SiO₂ DC-Plastikfolien 60 F₂₅₄ plates with detection accomplished by spraying with CeSO₄, I₂, and vanillin-H₂SO₄ followed by heating at 100 °C. The molecular docking studies were conducted using Auto Dock Vina, M.G.L tools 1.5.7, and Discovery Studio 4.5 as a visualizer. The human-acetylcholinesterase enzyme (AChE) (PDB 6O4W) was used as a receptor for the docking study and donepezil as a reference drug.

The identification and quantification of phenolic compounds in cladode extracts was performed in triplicate (an analysis for each of the three extractions/replicas) using an Agilent 1200 Liquid Chromatography system (Agilent Technologies, Palo Alto, CA, USA) and the chromatographic conditions and column were the same already reported by Sabella et al. [13 (link)]. The identification of phenolic compounds was confirmed by a TOF LC/MS system (Agilent 6320, Agilent Technologies, Palo Alto, CA, USA), equipped with a dual ESI interface operating in negative ion mode [13 (link)].
The identified phenolic compounds were quantified by the external standard method using a six-point calibration curve of p-hydroxybenzoic acid (0.5–100 mg/L), rutin (0.5–50 mg/L), isorhamnetin (0.5–50 mg/L), and narcissin (0.5–50 mg/L).