The species Cynara cardunculus is consumed as part of the Mediterranean diet and consists of the globe artichoke [var. scolymus (L.) Fiori], the cultivated cardoon (var. altilis DC.), and the wild cardoon [var. sylvestris (Lamk) Fiori]. The objective of this study was to investigate, in immature inflorescences, the main flavonoids and phenolic acids (caffeoylquinic acids, apigenin, and luteolin derivatives) by HPLC/diode array detection/mass spectrometry. Apigenin derivatives represented the major class in all samples investigated, highest in cardoon forms. Caffeoylquinic acids and luteolin derivatives were observed in var. scolymus only. Data allowed discrimination of globe artichoke from the related species on the basis of the profile of compounds analyzed. Our results suggest the possible use of cultivated and wild cardoon as a source of phenolic acids and flavonoids and indicate that artichoke consumption is an excellent dietary source of apigenin and other flavones.

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Human bioavailability of the flavonoid dihydrochalcones is little understood, and no evidence exists for C-glycosyl flavonoid absorption in humans. The present study uses catechol-O-methyltransferase to generate methylated metabolites of aspalathin (a C-glycosyl dihydrochalcone from rooibos tea). One of the methylated forms, both with and without glucuronidation, was detected using LC-MS/MS in the urine of human subjects (n = 6), demonstrating that deglycosylation is not a prerequisite for C-glycosyl flavonoid absorption. Methylation is catalysed by both intestine and liver cytosolic extracts. The results show that flavonoid C-glycosides are methylated and glucuronidated in vivo in an intact form in humans.

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BackgroundAspartame is a commonly used intense artificial sweetener, being approximately 200 times sweeter than sucrose. There have been concerns over aspartame since approval in the 1980s including a large anecdotal database reporting severe symptoms. The objective of this study was to compare the acute symptom effects of aspartame to a control preparation.MethodsThis was a double-blind randomized cross over study conducted in a clinical research unit in United Kingdom. Forty-eight individual who has self reported sensitivity to aspartame were compared to 48 age and gender matched aspartame non-sensitive individuals. They were given aspartame (100mg)-containing or control snack bars randomly at least 7 days apart. The main outcome measures were acute effects of aspartame measured using repeated ratings of 14 symptoms, biochemistry and metabonomics.ResultsAspartame sensitive and non-sensitive participants differed psychologically at baseline in handling feelings and perceived stress. Sensitive participants had higher triglycerides (2.05 ± 1.44 vs. 1.26 ± 0.84mmol/L; p value 0.008) and lower HDL-C (1.16 ± 0.34 vs. 1.35 ± 0.54 mmol/L; p value 0.04), reflected in 1H NMR serum analysis that showed differences in the baseline lipid content between the two groups. Urine metabonomic studies showed no significant differences. None of the rated symptoms differed between aspartame and control bars, or between sensitive and control participants. However, aspartame sensitive participants rated more symptoms particularly in the first test session, whether this was placebo or control. Aspartame and control bars affected GLP-1, GIP, tyrosine and phenylalanine levels equally in both aspartame sensitive and non-sensitive subjects.ConclusionUsing a comprehensive battery of psychological tests, biochemistry and state of the art metabonomics there was no evidence of any acute adverse responses to aspartame. This independent study gives reassurance to both regulatory bodies and the public that acute ingestion of aspartame does not have any detectable psychological or metabolic effects in humans.Trial RegistrationISRCTN Registry ISRCTN39650237

Physiologically obtainable quercetin concentrations are capable of ameliorating angiotensin II-induced endothelial nitric oxide and superoxide imbalance via protein kinase C-independent restoration of p47(phox) gene and protein expression.

A et al (2020) Physiologically relevant screening of polyphenol-rich commercial preparations for bioactivity in vascular endothelial cells and application to healthy volunteers: A viable workflow and a cautionary tale. Biochemical Pharmacology. 173: 113754. Rights