Discovery of Intake Biomarkers of Lentils, Chickpeas, and White Beans by Untargeted LC–MS Metabolomics in Serum and Urine

Abstract

Scope To identify reliable biomarkers of food intake (BFIs) of pulses. Methods and results A randomized crossover postprandial intervention study is conducted on 11 volunteers who consumed lentils, chickpeas, and white beans. Urine and serum samples are collected at distinct postprandial time points up to 48 h, and analyzed by LC‐HR‐MS untargeted metabolomics. Hypaphorine, trigonelline, several small peptides, and polyphenol‐derived metabolites prove to be the most discriminating urinary metabolites. Two arginine‐related compounds, dopamine sulfate and epicatechin metabolites, with their microbial derivatives, are identified only after intake of lentils, whereas protocatechuic acid is identified only after consumption of chickpeas. Urinary hydroxyjasmonic and hydroxydihydrojasmonic acids, as well as serum pipecolic acid and methylcysteine, are found after white bean consumption. Most of the metabolites identified in the postprandial study are replicated as discriminants in 24 h urine samples, demonstrating that in this case the use of a single, noninvasive sample is suitable for revealing the consumption of pulses. Conclusions The results of the present untargeted metabolomics work reveals a broad list of metabolites that are candidates for use as biomarkers of pulse intake. Further studies are needed to validate these BFIs and to find the best combinations of them to boost their specificity.

The Gut Microbiome and Abiotic Factors as Potential Determinants of Postprandial Glucose Responses: A Single-Arm Meal Study

“…Compliance to the standardization procedures was evaluated by self-assessment questionnaires on the test day. In addition, to assess whether the participants had in fact consumed the standardized meal including lentils the evening before the test day, we performed ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) on serum samples as previously published ( 17) and checked for the presence of tryptophan betaine (247.1448 [M + H], retention time 2.85 min), a biomarker of chickpeas and lentils peaking in blood 4-6 h after consumption before slowly being excreted (18). Tryptophan betaine was detected in considerable amounts in all serum samples except from one male subject (Supplementary Figure 1), suggesting that all participants except one had been compliant and consumed the standardized evening meal containing lentils.…”

Design and Characterisation of a Randomized Food Intervention That Mimics Exposure to a Typical UK Diet to Provide Urine Samples for Identification and Validation of Metabolite Biomarkers of Food Intake

“…UK government policy recommends the consumption of more beans and pulses and less red and processed meat (25). However, there is very limited data on potential urinary biomarkers for non-meat protein-rich foods, such as beans, lentils, and other pulses (55,56). Here we propose pyrogallol sulfate and glucuronide as potential markers of overall legume consumption (beans, peanuts, peas, soy).…”

Urine Metabolites Associated with the Dietary Approaches to Stop Hypertension (DASH) Diet: Results from the DASH‐Sodium Trial

“…[ 41 ] Phloroglucinol sulfate is a metabolite of phlorotannin, a polyphenolic compound, and, similar to 3,5‐dihydroxybenzoic acid, is hypothesized to be produced from microbial degradation of polyphenols. [ 42 ] Phloroglucinol sulfate in urine has been most frequently detected in biological samples after seaweed intake, but has also been detected after consuming other foods such as grapes, beans, and lentils. [ 42–44 ] Galactonate is derived from galactose, a monosaccharide that is found in dairy, syrups, and small amounts in pulses and seeds.…”

“…[ 42 ] Phloroglucinol sulfate in urine has been most frequently detected in biological samples after seaweed intake, but has also been detected after consuming other foods such as grapes, beans, and lentils. [ 42–44 ] Galactonate is derived from galactose, a monosaccharide that is found in dairy, syrups, and small amounts in pulses and seeds. [ 45 ] Serum concentration of galactonate was positively associated with the DASH diet in the original DASH feeding study and was identified as one of the top 5 important metabolites which distinguished higher versus lower adherence to the DASH diet using food frequency questionnaire data from the Cancer Prevention Study‐II Nutrition Cohort.…”