Unraveling the active hypoglycemic agent trigonelline in Balanites aegyptiaca date fruit using metabolite fingerprinting by NMR.
Trigonelline (3-carboxy-1-methyl pyridinium) was identified as a relevant bioactivity and taste imparting component in Balanites aegyptiaca fruit, using (1)H NMR of crude extracts without any fractionation or isolation step. The structural integrity of trigonelline was established within the extract matrix via(1)H NMR, (1)H-(1)H COSY, HMQC and HMBC and by comparison with authentic standard. A quantitative (1)H NMR method (qHNMR) was used to determine trigonelline concentrations in the peel and pulp of B. aegyptiaca fruit of 8 and 13mgg(-1), respectively. Trigonelline so far has not been reported from B. aegyptiaca or its genus as it easily escapes LC-MS based detection. Its discovery provides novel insight into the balanite fruits antidiabetic properties as the compound is known for a pronounced hypoglycemic effect. In addition, it is likely to impart the perceptible bitter taste portion to balanites sweet bitter taste. UPLC-MS of the crude extract additionally revealed the fruit flavonoid pattern showing quercetin/isorhamnetin flavonol conjugates in addition to epicatechin, the latter being present at much lower levels.
Pharmacognosy Department, College of Pharmacy, Cairo University, Cairo, Kasr el Aini St., P.B. 11562, Egypt. Electronic address: mohamed.farag@pharma.cu.edu.eg.
Mohamed A
MA
Farag
Leibniz Institute of Plant Biochemistry, Dept. Bioorganic Chemistry, Weinberg 3, 06120 Halle (Saale), Germany.
Andrea
A
Porzel
Leibniz Institute of Plant Biochemistry, Dept. Bioorganic Chemistry, Weinberg 3, 06120 Halle (Saale), Germany.
Ludger A
LA
Wessjohann
D000470:Alkaloids / Q000032:analysis*; D032430:Balanites / Q000737:chemistry*; D002853:Chromatography, Liquid; D005638:Fruit; D007004:Hypoglycemic Agents / Q000032:analysis*; D013058:Mass Spectrometry; D055432:Metabolomics / Q000379:methods* / Q000592:standards; D015394:Molecular Structure; D010936:Plant Extracts / Q000032:analysis*; D066244:Proton Magnetic Resonance Spectroscopy / Q000592:standards; D012015:Reference Standards; D013649:Taste
D000470:Alkaloids; D007004:Hypoglycemic Agents; D010936:Plant Extracts; C009560:trigonelline
Alkaloid; Antidiabetic natural product; Balanites aegyptiaca; NMR fingerprinting; Trigonelline