Determination of d-fagomine in buckwheat and mulberry by cation exchange HPLC/ESI–Q-MS

Abstract

D-Fagomine is an iminosugar first found in buckwheat (Fagopyrum esculentum Moench) which if used as a dietary supplement or functional food component may reduce the risks of developing insulin resistance, becoming overweight and suffering from an excess of potentially pathogenic bacteria. As D-fagomine may become increasingly important to the food industry, a reliable analytical method for its determination in natural plant sources and foodstuffs is desirable. We have devised a method to separate D-fagomine from its diastereomers 3-epi-fagomine and 3,4-di-epi-fagomine in a single run by cation exchange high-performance liquid chromatography (HPLC) with detection and quantification by mass spectrometry using electrospray ionisation and a simple quadrupole analyser (ESI-Q-MS). The method is validated and applied to the determination of D-fagomine in buckwheat groats (6.7-44 mg kg(-1)), leaves, bran and flour. We show that buckwheat contains 3,4-di-epi-fagomine (1.0-43 mg kg(-1)), which has not previously been reported in this source. The procedure is also applied to mulberry (Morus alba) leaves, which contain D-fagomine and 3-epi-fagomine as minor components. The new method provides a means for convenient and accurate determination of D-fagomine in plant samples and foodstuffs.

Effect of different planting areas on the chemical compositions and hypoglycemic and antioxidant activities of mulberry leaf extracts in Southern China

“…The abundant water resource could probably promote the synthesis of fagomine. According to another study, fagomine was also found in the roots of Xanthocersis zambesiaca at a content 1.30 mg/g [ 29 ]; however, the contents of fagomine from Chongqing Fuling could reach to 2.30 mg/g, which were much higher than that of Xanthocersis zambesiaca . In addition, the biomass of the leaves was much higher than that of roots and leaves that were much easier to obtain, thus, mulberry leaves are more suitable as a resource of fagomine.…”

Chlorogenic Acid and Rutin Play a Major Role in the In Vivo Anti-Diabetic Activity of Morus alba Leaf Extract on Type II Diabetic Rats

“…In view of the scientific literature, currently the iminosugars seem to be held the most important active constituents of mulberry leaves. These compounds lack a UV absorbing cromophore group, which makes them less convenient marker compounds: most typically sophisticated HPLC-MS techniques are suggested to their determination [23], [24].In our preliminary experiments [25], we have found high amounts of chlorogenic acid, rutin and isoquercitrin present in a 70% ethanol extract of the white mulberry leaves, which extract was active in vivo ; structures of these three compounds are shown in Figure 1.…”

Fate of d-Fagomine after Oral Administration to Rats

“…The analytical method was adapted for biological fluids from a previously described procedure developed for the analysis of plant sources (buckwheat and mulberry) 1 . Modifications were introduced in the extraction step and, to improve selectivity and sensibility, triple quadrupole MS was used instead of single quadrupole MS. First, the MS parameters such as desolvation temperature, cone voltage or collision energy were optimized to improve better signal intensity for the analytes under study.…”

“…D-Fagomine and 1-deoxynojirimycin (DNJ) are polyhydroxylated piperidines, also known as iminocyclitols, azasugars or iminosugars, that are synthesized by various plants and microorganisms as secondary metabolites 1,2 . D-fagomine and DNJ can be found in foodstuffs such as bread, pasta and biscuits made from buckwheat 3 , and tea, snacks and biscuits made from mulberry 4 .…”