The effect of rutin on the stool metabolome

Bc. Michaela Antošová

Master's thesis

Abstract:

Rutin is the glycoside combining with the flavonol quercetin and it is found in a number of edible plants (buckwheat, black tea, martyrs and apples). It is a low toxicity flavonol that is easily absorbed and metabolized in the human body. Rutin has anti–inflammatory, anti– allergenic, antioxidant, anti–inflammatory and anti–cancer effects. Due to its properties, it is widely used in therapy and the cosmetic industry. The practical part of the diploma thesis was focused on the catabolism of rutin by faecal microbiota of large intestine. Rutin was fermented in an in vitro fecal fermentation system using fresh stool samples from 20 different donors. Spectral changes and metabolite formation were monitored at fermentation times 0, 2, 4, 8 and 24 hours. The samples were subjected to NMR analysis, the spectra were analyzed in XCMS and Chenomx 8.5, and then the results were statistically evaluated. The aim of the practical part was to determine the main catabolites of rutin and stool metabolom in the colon model. Rutin was metabolically transformed by a colon microbiota. Differences in the microbial transformation of rutin and its metabolites have been shown. The resulting metabolites were quercetin, quercetin-3-galactoside, 3-hydroxyphenylacetic acid, phloroglucinol and taxifolin. Differences in conversion rate and metabolic rate were found between stool samples obtained from individual donors. The second objective was to evaluate how the addition of rutin affects the stool metabolome. Based on the paired t-test performed between the results of the treated variants and the control, it can be said that there is no statistically significant difference between them. Thus, the metabolome was not affected by the addition of rutin. Furthermore, the effect of age on the metabolome composition after rutin treatment (difference observed for leucine and ethanol) was also found for the control variant regardless of rutin. For ethanol, fructose and glucose, a statistically significant difference was found in the intestinal metabolome concentration of the control variant. Ethanol at hour 0 was found to be 1.7 % more concentrated in the younger group than in the older group. At the same time, fructose was also present at a 1.1 % higher concentration in the younger group at hour 0, while at hour 2 the concentration was 0.8% higher in the younger group. The glucose concentration was observed to be 4.1 % higher in the younger group. The hypothesis of this work that rutin will be microbially transformed was confirmed. The hypothesis that the addition would affect the composition of the intestinal metabolome was not proven. The composition of the intestinal metabolome differed between the two age groups studied only in the concentration of leucine, with a 4.7 % higher concentration observed in the younger group at hour 8, while this was not observed for the other substances.

Keywords

gastrointestinal tract, health effects, intestinal microbiota, flavonoids, NMR spectroscopy, rutin

Language used: English

Date on which the thesis was submitted / produced: 19. 4. 2022

Thesis defence

• Supervisor: Ing. Veronika Jarošová
• Reader: Zuzana Hroncová, Ph.D.

Czech University of Life Sciences Prague

Faculty of Agrobiology, Food and Natural Resources

Master programme:
Sustainable Agriculture and Food Security