The Bioavailability of Red Clover Isoflavones (KLBIO)

The Effects of Processing and Matrices on Bioavailability of Red Clover Isoflavones in Healthy Women

Previous literature has shown that the molecular form of isoflavones (as aglycones or glycosides) and food matrices can influence the bioavailability of these compounds in humans and hence their efficacy. To determine the effects of processing and food matrices on the bioavailability of active compounds derived from red clover the investigators will execute a 5 phase, cross-over design, open label, RCT using 20 healthy women aged between 18 to 40 years. Participants will receive 5 different formulations of red clover and bioavailability will be monitored in blood plasma using LC-MS.

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Dietary supplement: Fermented red clover isoflavones in aglycone form; Dietary supplement: Unfermented glycosides (as aglycone equivalents)

Detailed Description

The aim of this study is to elucidate the effects food matrices and processing on the bioavailability of active compounds on the bioavailability of red clover derived isoflavones. 20 healthy participants will receive red clover derived isoflavones in five different formulations. The five formulations are split up into five phases:

Phase 1) Fermented extract in liquid form Phase 2) Fermented extract (freeze-dried) in capsule form Phase 3) Fermented extract (freeze-dried) in tablet form Phase 4) Fermented extract (concentrated) mixed in yogurt Phase 5) Un-fermented red clover in capsule or tablet form The trial will last 5-6 weeks for each participant. Plasma sample collection will take place both pre-and post- ingestion of a formulation, participants will receive blood tests at intervals -15 min, 0 min, 2hr, 4hr, 6hr, 8hr and 12hr (on the day of ingestion) and on the subsequent two mornings (24hr and 48hr) following the initiation of a phase. There will be a minimum. 5 day intervals between all phases (washout periods). Isoflavones biochanin A, formononetin, genistein and daidzein present in plasma will be detected using HPLC-MS for each phase, thus creating a bioavailability curve that can be compared to each of the other phases. The primary endpoint is to determine whether fermented extract is more bioavailable than unfermented extract.

• Study Type: Interventional
• Enrollment (Actual): 16
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Central Jutland Region
    • Aarhus, Central Jutland Region, Denmark, 8000
      • Aarhus University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 40 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion criteria:

• Healthy women
• Age: 18-40 years

Exclusion Criteria:

• Habitual intake of soy products, chickpeas or other supplements with a high content of isoflavones
• Hormone therapy
• Pregnant or breastfeeding
• Taking drugs affecting uptake
• Participation in other clinical trials within the last 3 months
• Severe cardiovascular, psychiatric, neurological and / or kidney disease
• Alcohol or substance abuse
• Acute illness

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

5

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Capsule (aglycone); single bolus 40mg isoflavone formulation of fermented extract in freeze-dried capsule. Fermented red clover isoflavones in aglycone form	Dietary supplement: Fermented red clover isoflavones in aglycone form; Fermented isoflavones in aglycone form
Active Comparator: Tablet (aglycone); single bolus 40mg isoflavone aglycone formulation of fermented extract in freeze-dried tablet. Fermented red clover isoflavones in aglycone form	Dietary supplement: Fermented red clover isoflavones in aglycone form; Fermented isoflavones in aglycone form
Active Comparator: Yoghurt (aglycone); single bolus 40mg isoflavone aglycone formulation of fermented extract mixed with yoghurt Fermented red clover isoflavones in aglycone form	Dietary supplement: Fermented red clover isoflavones in aglycone form; Fermented isoflavones in aglycone form
Active Comparator: Liquid extract (aglycone); single bolus 40mg isoflavone aglycone formulation of fermented extract in liquid Fermented red clover isoflavones in aglycone form	Dietary supplement: Fermented red clover isoflavones in aglycone form; Fermented isoflavones in aglycone form
Active Comparator: Tablet unfermented (glycoside); single bolus 40mg isoflavone aglycone equivalent tablet formulation of unfermented red clover isoflavones Unfermented glycosides (as aglycone equivalents)	Dietary supplement: Unfermented glycosides (as aglycone equivalents); Unfermented aglycone equivalents in glycoside form

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Bioavailability of isoflavones in terms of fermented vs unfermented formulations	As measured by iAUC plasma concentrations of isoflavones over 48 hours	-15min, 0hr, 2hr, 4hr, 6hr, 8hr, 12hr, 24hr, 48hr

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Bioavailability of isoflavones in terms of matrices (tablet, capsule, yoghurt and liquid)	As measured by iAUC plasma concentrations of isoflavones over 48 hours	-15min, 0hr, 2hr, 4hr, 6hr, 8hr, 12hr, 24hr, 48hr

Collaborators and Investigators

• Sponsor: University of Aarhus
• Collaborators: Future Food Innovation; Southern Danish University; Herrens Mark A/S; Natur Drogeriet A/S
• Investigators: Principal Investigator: Per B Jeppesen, Prof. PhD, University of Aarhus

Study record dates

Study Major Dates

• Study Start: October 1, 2014
• Primary Completion (Actual): May 1, 2022
• Study Completion (Actual): May 1, 2022

Study Registration Dates

• First Submitted: October 8, 2014
• First Submitted That Met QC Criteria: October 14, 2014
• First Posted (Estimate): October 15, 2014

Study Record Updates

• Last Update Posted (Actual): May 23, 2022
• Last Update Submitted That Met QC Criteria: May 17, 2022
• Last Verified: December 1, 2015

More Information

Terms related to this study

• Keywords: Bioavailability; Human; Plasma; Isoflavones; Cross-over; Processing
• Other Study ID Numbers: KLBIO 07-10-14