Simulated Gastrointestinal Biotransformation of Chlorogenic Acid, Flavonoids, Flavonolignans and Triterpenoid Saponins in Cecropia obtusifolia Leaf Extract

Abstract

It is well known that biotransformation processes in the human body are crucial to form potentially bioactive metabolites from particular classes of natural products. However, little research has been conducted concerning the bioavailability of polyphenols, especially in the colon. The gastrointestinal stability and colonic biotransformation of the crude extract of the leaves of Cecropia obtusifolia, rich in flavone C-glycosides, was investigated under in vitro conditions, and the processing and interpretation of results were facilitated by using an automated machine learning model. This investigation revealed that flavone C-glycosides and flavonolignans from C. obtusifolia were stable throughout their passage in the simulated gastrointestinal tract including the colon phase. On the other hand, the colon bacteria extensively metabolized chlorogenic acid, flavonol, and triterpenoid O-glycosides. This investigation revealed that the colonic microbiota has an important role in the biotransformation of some chemical constituents of this extract.

Antiplasmodial Oleanane Triterpenoids from Terminalia albida Root Bark

“…The 1 H NMR spectrum recorded in pyridine-d 5 showed six methyl singlets at δ H 1.67, 1.46, 1.37, 1.06, 1.06, and 0.85, which were attributed to methyl groups C-27, C-25, C-26, C-24, C-29, and C-30, respectively (Table 1). Additional proton resonances observed included those attributed to an olefinic proton at δ H 6.11 (1H, br s), three oxymethine protons at δ 13 C NMR spectra (Tables 1 and 2) in pyridine-d 5 were similar to those of compound 1. The 1 H NMR spectrum of 2 showed six methyl singlets at δ H 1.00, 1.04, 1.17, 1.37, 1.39, and 1.45.…”

“…Nowadays, it is well know that MN can provide more structural information by assigning similar chemical scaffolds to their related neighbors and eventually give potential chemical scaffolds for unknown nodes, but MN cannot provide insights into the annotation of similar structures. 14 Therefore, a complementary identification strategy using preparative LC-MS and 1D ( 1 H and 13 C NMR, DEPT-135, DEPT-90) and 2D (COSY, HSQC, HMBC) NMR data analysis has been applied, resulting in the isolation and complete identification of 10 target compounds. 1 H and 13 C NMR assignments are listed in Tables 1 and 2, respectively.…”

“…14 Therefore, a complementary identification strategy using preparative LC-MS and 1D ( 1 H and 13 C NMR, DEPT-135, DEPT-90) and 2D (COSY, HSQC, HMBC) NMR data analysis has been applied, resulting in the isolation and complete identification of 10 target compounds. 1 H and 13 C NMR assignments are listed in Tables 1 and 2, respectively. Compound 1 was obtained as a white powder, and the molecular formula (C 36 H 56 O 12 ) was determined by HR-ESIMS, yielding a deprotonated ion at m/z 679.3710 [M − H] − .…”

“…12 Although the n-BuOH fraction was not active, the possibility cannot be excluded that this polar fraction contains inactive glycosides, which may release active aglycones after removal of the glycosidic moieties in the gastrointestinal tract, more in particular in the colon. 13 Therefore, in the present study the n-BuOH fraction of the total root extract of T. albida has been subjected to extensive dereplication studies. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) combined with molecular networking and in silico MS/MS analysis was performed prior to subsequent isolation of the target compounds.…”

Availability and Metabolic Fate of Olive Phenolic Alcohols Hydroxytyrosol and Tyrosol in the Human GI Tract Simulated by the In Vitro GIDM–Colon Model

“…Moreover, in such in vitro systems, the interference of the endogenously produced metabolites is avoided. The in vitro GastroIntestinal Dialysis–colon model (GIDM–colon) is such a system, which has been introduced in 2015 by Breynaert and co–workers [ 40 ], enriched later with a colonic phase and used in several studies [ 44 , 45 , 46 ]. For colon phase catabolism, a pooled human fecal suspension is used.…”