Contribution of Berry Polyphenols to the Human Metabolome

Abstract

Diets rich in berries provide health benefits, however, the contribution of berry phytochemicals to the human metabolome is largely unknown. The present study aimed to establish the impact of berry phytochemicals on the human metabolome. A “systematic review strategy” was utilized to characterize the phytochemical composition of the berries most commonly consumed in the USA; (poly)phenols, primarily anthocyanins, comprised the majority of reported plant secondary metabolites. A reference standard library and tandem mass spectrometry (MS/MS) quantitative metabolomics methodology were developed and applied to serum/plasma samples from a blueberry and a strawberry intervention, revealing a diversity of benzoic, cinnamic, phenylacetic, 3-(phenyl)propanoic and hippuric acids, and benzyldehydes. 3-Phenylpropanoic, 2-hydroxybenzoic, and hippuric acid were highly abundant (mean > 1 µM). Few metabolites at concentrations above 100 nM changed significantly in either intervention. Significant intervention effects (p < 0.05) were observed for plasma/serum 2-hydroxybenzoic acid and hippuric acid in the blueberry intervention, and for 3-methoxyphenylacetic acid and 4-hydroxyphenylacetic acid in the strawberry intervention. However, significant within-group effects for change from baseline were prevalent, suggesting that high inter-individual variability precluded significant treatment effects. Berry consumption in general appears to cause a fluctuation in the pools of small molecule metabolites already present at baseline, rather than the appearance of unique berry-derived metabolites, which likely reflects the ubiquitous nature of (poly)phenols in the background diet.

Plasma and Urinary (Poly)phenolic Profiles after 4-Week Red Raspberry (Rubus idaeus L.) Intake with or without Fructo-Oligosaccharide Supplementation

“…Unabsorbed anthocyanins and phenyl-γ-valerolactones may be metabolized to various phenolic acids [ 5 , 6 , 7 ]. The microbial catabolism of anthocyanin is performed by cleavage of the heterocyclic flavylium ring (C ring fission), followed by microbial dehydroxylation or decarboxylation [ 5 , 6 ].…”

“…Unabsorbed anthocyanins and phenyl-γ-valerolactones may be metabolized to various phenolic acids [ 5 , 6 , 7 ]. The microbial catabolism of anthocyanin is performed by cleavage of the heterocyclic flavylium ring (C ring fission), followed by microbial dehydroxylation or decarboxylation [ 5 , 6 ]. The different T max of various subgroups of phenolic acids indicated a potential pathway for the catabolism of anthocyanins ( Figure 3 ), such as: anthocyanins (2 h) → benzaldehydes (1 h) → cinnamic acids (2 h) → phenylpropionic acids (no peak time) → phenylacetic acids (2–3 h) → benzoic acids (3–4 h) → hippuric acids (4–24 h).…”

“…Whole red raspberries (RRB) and their (poly)phenol components have been associated with metabolic health, including glucose control, increasing insulin sensitivity, and improving lipid profiles in humans, and reducing fat mass in animal studies [ 3 , 4 ]. Some of these (poly)phenols could be absorbed intact, while majority of them are degraded to products of gut microbial metabolism [ 5 , 6 , 7 ]. For example, the majority of ellagitannins and oligo- and poly-meric flavan-3-ols escape proximal gastrointestinal (GI) tract absorption and are catabolized in the colon to urolithins and phenyl-γ-valerolactones, respectively, by gut microbiota [ 7 , 8 ].…”

Blueberry and/or Banana Consumption Mitigate Arachidonic, Cytochrome P450 Oxylipin Generation During Recovery From 75-Km Cycling: A Randomized Trial

“…In a previous global metabolomics-based study conducted in our laboratories, 2-weeks ingestion of blueberry and green tea polyphenols vs. placebo was associated with significant increases in gut-derived phenolic metabolites ( 7 ). Polyphenols such as blueberry anthocyanins undergo extensive biotransformation after ingestion with the majority reaching the lower bowel where microbial degradation produces gut-derived phenolic metabolites that can be reabsorbed into the systemic circulation and exert a variety of bioactive effects ( 8 – 11 ).…”

Antioxidant, functional properties and health‐promoting potential of native South American berries: a review

“…The largest and most diverse subclasses of phenolic compounds reported in berries were anthocyanins, followed by flavones and flavonols. 37 The chemical structures of anthocyanins are water-soluble glycosides of polyhydroxyl and polymethoxyl derivatives of 2-phenylbenzopyrylium or flavylium salts. 38 Six anthocyanins have been identified in berries, cyanidin, delphinidin, malvidin, peonidin, pelargonidin, and petunidin.…”