In vivo study of the bioavailability and metabolic profile of (poly)phenols after sous-vide artichoke consumption.

Artichokes are a rich source of (poly)phenols, mainly caffeoylquinic acids, but little is known about their bioavailability from this source. This study investigated the absorption, metabolism and excretion of (poly)phenols after sous-vide artichoke consumption (5776 µmol of (poly)phenols) by healthy volunteers. Seventy-six (poly)phenol metabolites were identified by UHPLC-MS/MS using authentic standards, including acyl-quinic acids plus C6-C3, C6-C1, C6-C2, C6-C1-N, C6-C0 metabolites, and their phase-II conjugates. The major metabolites were 3'-methoxy-4'-hydroxycinnamic acid, 3'-methoxycinnamic acid-4'-sulfate, and 4'-hydroxycinnamic acid-3'-sulfate, which appeared early in plasma (Tmax < 4 h); plus 3-(3'-methoxy-4'-hydroxyphenyl)propanoic acid, 3-(4'-methoxyphenyl)propanoic acid-3'-glucuronide, 3-(3'-hydroxyphenyl) propanoic acid and hippuric acids, which appeared later (Tmax > 6 h). The 24 h urinary recovery averaged 8.9% (molar basis) of the (poly)phenols consumed. Hepatic beta-oxidation of 3',4'-dihydroxycinnamic acid and methylated conjugates occurred, but was limited (<0.04%). 3'-Methylation exceeded 4'-methylation and interindividual variability was high, especially for gut microbial metabolites (up to 168-fold).

Bioaccessibility of Tudela artichoke (Cynara scolymus cv. Blanca de Tudela) (poly)phenols: the effects of heat treatment, simulated gastrointestinal digestion and human colonic microbiota.

The aim of this study was to evaluate the bioaccessibility of (poly)phenolic compounds in Tudela artichokes (Cynara scolymus cv. Blanca de Tudela) after an in vitro gastrointestinal digestion and the effect of the human colonic microbiota. A total of 28 (poly)phenolic compounds were identified and quantified by LC-MS/MS in raw, boiled, sous vide and microwaved Tudela artichokes. Out of these, sixteen were phenolic acids, specifically caffeoylquinic acids (CQAs) and other minor hydroxycinnamic acid derivatives, ten flavonoids belonging to the family of flavones (apigenin and luteolin derivatives) and two lignans (pinoresinol derivatives). Sous vide and microwaving caused mainly transesterification reactions of CQAs but maintained or even augmented the total (poly)phenolic contents of artichokes, while boiling decreased (poly)phenolic compounds by 25% due to leaching into the boiling water. Heat treatment exerted a positive effect on the bioaccessibility of (poly)phenols after gastrointestinal digestion. In raw artichokes, only 1.6% of the total (poly)phenolic compounds remained bioaccessible after gastrointestinal digestion, while in artichoke samples cooked by sous vide, boiled and microwaved, the percentage of bioaccessibility was 60.38%, 59.93% and 39,03% respectively. After fecal fermentation, 20 native (poly)phenolic compounds and 11 newly formed catabolites were quantified. 48 h of fecal fermentation showed that native (poly)phenols are readily degraded by colonic microbiota during the first 2 h of incubation. The colonic degradation of artichoke (poly)phenols follows a major pathway that involves the formation of caffeic acid, dihydrocaffeic acid, 3-(3'-hydroxyphenyl)propionic acid, 3-phenylpropionic acid and phenylacetic acid, with 3-phenylpropionic acid being the most abundant end product. The catabolic pathways for colonic microbial degradation of artichoke CQAs are proposed.

Quantitative Assessment of Dietary (Poly)phenol Intake: A High-Throughput Targeted Metabolomics Method for Blood and Urine Samples.

Many studies have associated the consumption of (poly)phenol-rich diets with health benefits. However, accurate high-throughput quantitative methods for estimating exposure covering a broad spectrum of (poly)phenols are lacking. We have developed and validated a high-throughput method for the simultaneous quantification of 119 (poly)phenol metabolites in plasma and urine using ultra high-performance liquid chromatography coupled with triple quadrupole mass spectrometry, with a very fast sample treatment and a single run time of 16 min. This method is highly sensitive, precise, accurate, and shows good linearity for all compounds (R2 > 0.992). This novel method will allow a quantitative assessment of habitual (poly)phenol intake in large epidemiological studies as well as clinical studies investigating the health benefits of dietary (poly)phenols.

Impact of cooking process on nutritional composition and antioxidants of cactus cladodes (Opuntia ficus-indica).

The impact of cooking methods (boiling, microwaving, griddling and frying in olive and soybean oils) on nutritional composition (protein, minerals, fat, carbohydrates, fibre, fatty acid profile and energy), antioxidant capacity and (poly)phenolic compounds of cactus cladodes (Opuntia ficus-indica) was evaluated. Culinary processes, except boiling, increased soluble and insoluble fibre up to 5.0g/100g becoming a good fibre source. Cactus cladodes fried in olive oil showed a healthier fatty acid profile and lower ω-6/ω-3 ratio than in soybean oil. Flavonoids accounted for 80% of total (poly)phenolic compounds, being isorhamnetin the most abundant. Heat treatment, particularly griddling and microwaving, increased every flavonoid and phenolic acid up to 3.2-fold higher than in raw samples, and consequently their antioxidant capacity. Even boiling induced losses in total (poly)phenols and antioxidant capacity by leaching into water, the main compounds were maintained. Principal Component Analysis distributed heat treated cactus cladodes according to their distinctive polyphenols and antioxidant capacity.