Quantification of Total Folate, Folate Species and Polyglutamyl Folate Distribution in Winged Beans (<i>Psophocarus tetragonolobus</i> (L) DC) from Different Cultivars and Growth Stages by Ultra-High Performance Liquid Chromatography Tandem Mass Spectrometry

Abstract

Summary Winged beans are an important natural source of some micronutrients. This paper presents the first complete characterization of folate derivatives including polyglutamyl 5-methyltetrahydrofolate (5-CH3-H4PteGlun), folate species and total folate accumulating in pods and immature seeds of winged beans from 9 cultivars and 7 growth stages. 5-CH3-H4PteGlun and folate species were determined with a UHPLC-MS/MS method. Accurate determination of 5-CH3-H4PteGlun and folate species was optimized and validated according to EMA guidelines including method selectivity, sensitivity, linearity, accuracy, precision, matrix effect and carry-over. The level of total folate is in the range of 73-200 g/100 g in the pods and 33-61 g/100 g in the immature seeds. The predominant folate species in winged beans is 5-CH3-H4PteGlu1. 5-CH3-H4PteGlu5 is the major polyglutamyl folate derivative. The level of total folate is increased about 4 fold with advancing maturity. For pods, the chain length is increased with growth which shifts from 5-CH3-H4PteGlu1 in the early stage to 5-CH3-H4PteGlu5 and 5-CH3-H4PteGlu6 in the 7th stage. Our findings demonstrate that winged beans are good source of folate. The validated UHPLC-MS/MS method allows for the determination of 5-CH3-H4PteGlun and folate species from other vegetable matrices.

The use of a plant enzyme for rapid and sensitive analysis of naturally-occurring folates in food by liquid chromatography-tandem mass spectrometry

“…Chicken pancreas is only able to remove polyglutamyl tail until diglutamate forms and it is, therefore, combined with some other deconjugases in LC-MS/MS analysis. Rat plasma/serum are the most commonly used, probably due to the commercial availability and very low amounts of endogenous folates [32,33,[35][36][37]. In 1990, Martin et al [38] introduced tri-enzyme treatment which included the use of α-amylase and protease prior the GGH in order to release folates from food matrix and improve their extraction.…”

Optimized Extraction and Characterization of Folates From Date Palm Fruits and Their Tracking During Fruits Wine Fermentation

“…To take into consideration folate brought by the fermentation reagents, the endogenous folate content in the fermentation reagents was determined as suggested in early reports (10,18). Specifically, 5-g samples of fermentation reagents (pectinase and ACTIFLORE F33 yeast) were suspended in 20 ml of an extraction buffer (100-mM ammonium acetate; 1% ascorbic acid; 0.2% 2mercaptoethanol; pH, 7.89) and homogenized for 2 min using a homogenizer (IKA T18 Basic; IKA, Staufen, Germany) at 4 • C. The homogenates were immediately boiled for 15 min, cooled on ice to room temperature, and reconstituted to 25 ml.…”

“…Although this method is adequate for determining total folate content, it cannot distinguish diverse folate vitamers ( 7 ). Previously, we developed a UHPLC-MS/MS method for quantification of different folate vitamers in different plants with high sensitivity and accuracy ( 10 ).…”

Comprehensive Vitamer Profiling of Folate Mono- and Polyglutamates in Baker’s Yeast (Saccharomyces cerevisiae) as a Function of Different Sample Preparation Procedures

“…Almost the entire research focuses on the respective monoglutamates after enzymatic deconjugation of the polyglutamate vitamers [20,49,63]. Only a few studies focused on the polyglutamate distribution of mammalian tissue [64,65], bacteria [65] and raw vegetables [64,[66][67][68]. Yeast, however, has not been analyzed in terms of polyglutamate vitamers which typically account for the major occurring form in vivo.…”

“…Alternative materials such as weak anion exchange materials [78], phenyl [74,[79][80][81] or C18 [82][83][84]-modified materials are used less frequently. Few studies also reported the use of hydrophilic-lipophilic-balanced (HLB) materials consisting of N-vinylpyrrolidon-divinylbenzol copolymers offering application for a broad range of analytes [66,85]. We wanted to compare different protocols for their applicability to studies of folate metabolites.…”