Phytochemical investigations and evaluation of antidiabetic potential of Prunus dulcis nuts

- Preparation of 70% ethanol extract of Prunus dulcis nuts and its successive fractionation.
- Chromatographic isolation and purification of compounds from ethyl acetate fraction.
- Spectral characterization of isolated compounds.
- HPLC-MS/MS analysis of 70% ethanol extract.
- PTP1B inhibition assay resulted in strongest activity for 70% ethanol extract.

Prunus dulcis has long been known as a source of nutrients in many traditional foods and healthy snack. Presence of various biologically active compounds, such as phenolic compounds including falvonoids, phenolic acids, tannins etc and vitamin E, bases for their antioxidant and other health promoting activities. The present study is focused on the phytochemical characterization through chromatographic isolation and purification, and mass spectrometric identification of various compounds along with evaluation of antidiabetic activity of various extracts of P. dulcis nuts. Stigmasitosterol-3-O-β-D-glucoside and α-d-Glucopyranosyl-(1 → 2)-β-d-fructofuranoside were isolated for the first time along with a known compound isolated previously from the skin of the almond. Mass spectrometric analysis delivered some compounds like catechin dihexoside, caffeoyl-6'-secologanoside and (epi)catechin-ethyl trimer which were detected for the first time in almond along with other compounds which have been identified in the skin of almond. Highest antidiabetic activity has been determined for 70% ethanol extract, even more than the control sample, among the other extracts evaluated. The published literature showed no such detailed study of the whole almond nuts as the main focus was on the brown almond skin, and is presented for the first time.