Aphichat Trakooncharoenvit1, Seiya Tanaka1, Erika Mizuta1, Tohru Hira1,2, Hiroshi Hara3,4. 1. Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan. 2. Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan. 3. Graduate School of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan. hara@chem.agr.hokudai.ac.jp. 4. Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589, Japan. hara@chem.agr.hokudai.ac.jp.
Abstract
PURPOSE: To investigate the effects of water-soluble dietary fibers (pectin, soybean fiber, and guar gum) on the bioavailability of quercetin glucoside mixture (Q3GM) comprising quercetin-3-O-glucoside (Q3G, 31.8%) and its glucose adducts. METHODS: Male Wistar/ST rats were fed test diet containing 0.7% Q3GM with or without 5% of each dietary fiber for 8 weeks. Total quercetin derivatives were evaluated with liquid chromatograph tandem mass spectrometry (LC-MS/MS) as total quercetin derivatives after enzymatic deconjugation in plasma, urine, and fecal samples on week 2, 4, 6 and 8. Quercetin glucuronides excreted in feces were also measured. RESULTS: Fiber feeding elevated cecal weight and reduced cecal pH, indicative of cecal fermentation promotion. Changes in plasma and urinary quercetin levels revealed three phases of quercetin metabolism, including cumulative, transient, and stable phases. On week 2, total quercetin derivatives were higher in plasma samples from three fiber-fed groups than those control groups; however, urinary excretion increased in fiber-fed groups on week 4. Soybean fiber upregulated plasma and urinary quercetin levels on week 6 and 8. Intestinal degradation of quercetin by bacteria, calculated from differences between aglycone ingestion and sum of urinary and fecal excretion, was suppressed after dietary fiber supplementation especially in pectin fiber, which may partly contribute to the increase in quercetin bioavailability. Fecal quercetin glucuronide excretion was high in soybean fiber-fed rats, suggestive of the reduction of β-glucuronidase in colon. CONCLUSION: Water-soluble dietary fibers, especially soybean fiber, enhanced quercetin bioavailability after chronic feeding and may promote beneficial effects of quercetin on disease prevention.
PURPOSE: To investigate the effects of water-soluble dietary fibers (pectin, soybean fiber, and guar gum) on the bioavailability of quercetin glucoside mixture (Q3GM) comprising quercetin-3-O-glucoside (Q3G, 31.8%) and its glucose adducts. METHODS: Male Wistar/ST rats were fed test diet containing 0.7% Q3GM with or without 5% of each dietary fiber for 8 weeks. Total quercetin derivatives were evaluated with liquid chromatograph tandem mass spectrometry (LC-MS/MS) as total quercetin derivatives after enzymatic deconjugation in plasma, urine, and fecal samples on week 2, 4, 6 and 8. Quercetin glucuronides excreted in feces were also measured. RESULTS: Fiber feeding elevated cecal weight and reduced cecal pH, indicative of cecal fermentation promotion. Changes in plasma and urinary quercetin levels revealed three phases of quercetin metabolism, including cumulative, transient, and stable phases. On week 2, total quercetin derivatives were higher in plasma samples from three fiber-fed groups than those control groups; however, urinary excretion increased in fiber-fed groups on week 4. Soybean fiber upregulated plasma and urinary quercetin levels on week 6 and 8. Intestinal degradation of quercetin by bacteria, calculated from differences between aglycone ingestion and sum of urinary and fecal excretion, was suppressed after dietary fiber supplementation especially in pectin fiber, which may partly contribute to the increase in quercetin bioavailability. Fecal quercetin glucuronide excretion was high in soybean fiber-fed rats, suggestive of the reduction of β-glucuronidase in colon. CONCLUSION:Water-soluble dietary fibers, especially soybean fiber, enhanced quercetin bioavailability after chronic feeding and may promote beneficial effects of quercetin on disease prevention.
Authors: Álvaro Fernández-Ochoa; María de la Luz Cádiz-Gurrea; Patricia Fernández-Moreno; Alejandro Rojas-García; David Arráez-Román; Antonio Segura-Carretero Journal: Molecules Date: 2022-01-25 Impact factor: 4.411