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Effect of L. Plantarum Probiotic Supplementation on Broccoli Sulforaphane Bioavailability: Randomised Double-blind Placebo-controlled Crossover Study

Not Applicable
Not yet recruiting
Conditions
Nutrition, Healthy
Interventions
Dietary Supplement: Broccoli sprouts extract supplementation
Registration Number
NCT06561893
Lead Sponsor
University of Exeter
Brief Summary

Broccoli has the precursor of an active compound (sulforaphane) that has shown a wide range of health promoting benefits. Sulforaphane formation depends on the conversion of glucoraphanin (precursor) by myrosinase enzyme. Thus, the bioavailability of sulforaphane is affected by myrosinase activity. Some bacteria, such as L. plantarum (probiotic), have shown they can also convert glucoraphanin to sulforaphane in vitro. This study investigates the effect of short-term L. plantarum supplementation on broccoli sulforaphane bioavailability in humans using a randomised double-blind placebo-controlled crossover trial.

Detailed Description

Brassicas (i.e. broccoli, kale, cabbage) are a group of edible plants that contain a phytochemical called glucoraphanin that upon enzymatic hydrolysis forms the bioactive form sulforaphane. Sulforaphane has shown consistent in vitro and in vivo (animals) anti-cancer activity. The enzyme responsible for this conversion is called myrosinase; however, the enzymatic activity of myrosinase can be affected by several biological factors (e.g. plant variety, growth conditions, etc...) and food processing (e.g. cooking, drying, etc...). Broccoli is one of the richest sources of glucoraphanin, but its myrosinase activity can be easily lost during cooking: 10 minutes at 70 °C reduces the enzyme activity by 95%. This means broccoli prepared this way will contain little to no biologically active sulforaphane. Therefore, is important to find strategies to increase the bioavailability of sulforaphane in broccoli and other brassicas for human consumption.

Certain bacteria have shown myrosinase-like activity and were able to convert glucoraphanin to sulforaphane in vitro, one of these bacteria is Lactiplantibacillus plantarum. This bacterium is present in the human gut, however, there is a large biological variability in the prevalence of this bacteria between individuals. Several human studies have demonstrated that chronic (\>1 week) consumption of probiotic supplements containing L. plantarum was able to increase the presence of this bacterium in human gut participants. Thus, the investigators aim to test if supplementing participants with L. plantarum will increase the bioavailability of sulforaphane, compared to placebo.

Recruitment & Eligibility

Status
NOT_YET_RECRUITING
Sex
All
Target Recruitment
12
Inclusion Criteria
  • healthy adults (male and female)
  • age range of 18-65 years
  • BMI range of 18-30 kg/m2
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Exclusion Criteria
  • have been on a course of antibiotics within the period of the past 3 months.
  • have allergies or intolerance towards probiotic substances or broccoli used in the study and/or food intolerances associated with gastrointestinal upset.
  • have been taking pre- or probiotics supplements regularly during the last month prior (this does not include foods containing probiotics and/or prebiotics foods)
  • are following any restricting diet (e.g., vegan, FODMAP, etc.).
  • have a gastrointestinal inflammatory condition (e.g., irritable bowel syndrome, inflammatory bowel diseases, coeliac diseases, constipation, etc.).
  • have a medical condition or take medication for any heart, endocrine, or metabolic condition, such as high blood pressure, high cholesterol, insulin resistance, or diabetes, or autoimmune disease.
  • are a pregnant and/or breastfeeding.
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Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Probiotic (L. plantarum) supplementationBroccoli sprouts extract supplementationDose: 20 Billion CFU/day for 14 days (total of two pills of 10 Billion CFU)
Placebo (dextrose) supplementationBroccoli sprouts extract supplementationDose: 700 mg of dextrose (total of two pills; 2 x 350 mg pills)
Primary Outcome Measures
NameTimeMethod
Bioavailability of sulforaphaneFrom baseline to the end of each condition at 2 weeks, followed by 2 weeks of wash-out, and before and after the next condition

Bioavailability (%) of sulforaphane (will be estimated by dividing the cumulative amount of sulforaphane mercapturic acid excreted in urine in 24 h by the consumed amount of glucoraphanin (Vermeulen et al., 2008)) before and after chronic consumption of L. plantarum compared with placebo.

Secondary Outcome Measures
NameTimeMethod
Sulforaphane pharmacokinetics: Area under the curveFrom baseline to the end of each condition at 2 weeks, followed by 2 weeks of wash-out, and before and after the next condition.

Measurement of the definite integral of the concentration of sulforaphane (and its metabolites) in blood plasma as a function of time.

Sulforaphane pharmacokinetics: TmaxFrom baseline to the end of each condition at 2 weeks, followed by 2 weeks of wash-out, and before and after the next condition.

Measurement of the time taken for sulforaphane (and its metabolites) to reach the maximum concentration (Cmax) after administration of the supplement that needs to be absorbed.

Sulforaphane pharmacokinetics: CmaxFrom baseline to the end of each condition at 2 weeks, followed by 2 weeks of wash-out, and before and after the next condition.

Measurement of the maximum plasma concentration (Cmax) of sulforaphane (and its metabolites) indicating the value of the highest concentrations reached in the plasma.

Trial Locations

Locations (2)

The Department of Public Health and Sport Sciences, University of Exeter Medical School, Faculty of Health and Life Sciences, University of Exeter

🇬🇧

Exeter, Devon, United Kingdom

Richard's Building, St Luke's Campus

🇬🇧

Exeter, Devon, United Kingdom

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