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Aframomum melegueta seeds are widely used as a spice in Africa. Two undescribed paradol-related compounds, (S)−9-hydroxy-[6]-paradol (1) and (9S)−3,9-dihydroxydihydro-[6]-paradol (2) together with eight reported constituents (3-10) were isolated and characterised from the methanol extract of A. melegueta seeds. Structure elucidation of these metabolites was achieved by means of NMR and mass spectroscopic data analyses. The absolute configuration of undescribed compounds (1 and 2) was determined using the modified Mosher's method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Stem and leaf of Cissus quadrangularis L. (Vitaceae), indigenous to Asia and Africa. • Stem/leaf samples were assessed for polyphenolics determination using HPTLC, UHPLC-PDA and LC-QToF. • The newly validated UHPLC-PDA method is used for quantitative determination. • LC-QToF method is described for the targeted and non-targeted analysis of compounds. • The different analytical methods provided fast and reliable procedures for quality assessment. Stem and leaf of Cissus quadrangularis L. (Vitaceae), indigenous to Asia and Africa, were used for medicinal and dietary purposes with limited information about the plant's phytochemistry. Stem and leaf samples were assessed for the simultaneous determination of polyphenolic compounds (catechin, epicatechin, quercetin-3- O - β -glucopyranoside, kaempferol-3- O - β -glucoside, quercetin-3- O - β -rhamnoside, leachianol F, amurensin A, pallidol, resveratrol, and quadrangularin A), using UHPLC-PDA-MS. The validation data showed that the method is precise, specific, accurate, and linear over the range of 0.5−100 μg/mL. Reversed-phase ultra-high performance liquid chromatography (UHPLC) fingerprints of the crude methanolic stem and leaf extracts of C. quadrangularis were obtained at different wavelengths based on their λ max. Polyphenolics were characterized using both UHPLC-PDA-MS and LC-QToF analysis. From liquid chromatography quadrupole time of flight-electrospray ionization mass spectrometry (LC-QToF) spectra, over 40 components were structurally correlated, and confirmation was based on the fragmentation characteristics and also from the information available in the literature. In addition to the LC-QToF method, a simple, fast HPTLC method was developed as a visual aid for the rapid qualitative analytical tool to help establish the quality assessment of botanical raw materials and dietary supplements claiming to contain Cissus. [ABSTRACT FROM AUTHOR]