Quercetin, vanillin and umbelliferon quantification in the tissue of broiler chickens dietary supplemented with these compounds

Relevance. Plant-derived compounds are attractive alternative to antibiotic growth promoters in livestock and poultry production. In our previous study, dietary supplementation of broiler chickens with the flavonoid quercetin, the phenolic aldehyde vanillin, and the o-hydroxycinnamic acid lactone umbelliferon (7-hydroxycoumarin) modulated the ceca microbiome, reduced systemic inflammation, and increased production efficiency, as measured by the EPEF index.

Objectives. To evaluate the content of free and conjugated (glucuronidated) quercetin, vanillin and umbelliferon in the muscles and liver of broiler chickens fed a 35-day basic diet supplemented with these compounds.

Material and methods. Quercetin, vanillin and umbelliferon were extracted with acetonitrile and formic acid, evaporated and re-dissolved in deionized water, and then purified using HLB cartridges. To release the conjugated compounds, hydrolysis with glucuronidase/arylsulfatase was additionally performed. The resulting samples were analyzed by HPLC-MS using a LCMS-8050 gas chromatograph - mass spectrometer (Shimadzu Corporation, Japan) with LabSolutions software installed.

Results. Tissue samples from broiler chickens fed quercetin did not contain this compound in a detectable concentration range, which may be a consequence of the effective quercetin metabolism by intestinal microflora and xenobiotic inactivation systems. Surprisingly, quantification of vanillin showed its presence in all analyzed samples, regardless of presence or absence in supplements. This result cannot be interpreted unequivocally and is currently speculated to be due to vanillin or similar cross-reacting substances in the basic diet. Umbelliferon concentrations of 17 ng/g (free) and 125 ng/g (sum of free and conjugated forms) were detected in only one liver sample of broiler chickens that received this compound at the maximum dosage (3.0 mg per 1 kg of feed).

Conclusion. The absence or low accumulation of free and glucuronidated quercetin, vanillin and umbelliferon in the muscles and liver of diet-supplemented broiler chickens has been shown. This result indicates the safety of these plant-derived molecules in poultry production without possible migration through food chains.