Effects of Brassica on human gut lactobacilli - version 2
Research type
Research Study
Full title
A human intervention trial investigating the effects of Brassica on human gut lactobacilli.
IRAS ID
158266
Contact name
Richard Mithen
Contact email
Sponsor organisation
Institute of Food Research
Research summary
Brassica vegetables, such as broccoli and cauliflower, are an important part of the diet and are associated with a reduced risk of many chronic diseases. The protective effect may be as a result of compounds contained within these vegetables, called glucosinolates (GSLs). GSLs can be changed into active compounds called isothiocyanates (ITCs) by a protein called myrosinase, which is found in the same vegetables. When we cook vegetables the myrosinase is inactivated and the change from GSLs to ITCs is carried out by our gut bacteria. It is the ITCs that are thought to be responsible for the protective effects against diseases. Our gut bacteria are also thought to help prevent diseases, in particular the lactobacilli which are often used as probiotic supplements. In this study we will ask participants to consume a low and high Brassica vegetable diet, consisting of broccoli, cauliflower, and a broccoli and sweet potato soup. We are interested in whether eating a diet rich in Brassica vegetables increases the number of gut lactobacilli and how the composition of the gut bacteria of the participant affects the rate of ITC excretion. We will collect stool samples from each participant and use these for phylogenetic analysis of the gut microbiota, and to see if the number of lactobacilli increases. We will collect urine samples to look at the rate of ITC excretion and assess whether these rates are associated with the gut microbiota. We will attempt to link eating a diet rich in Brassica vegetables, with increases in lactobacilli, and correlate bacterial phylogeny to the rate and/or the amount of GSL to ITC conversion by an individual. To date, very little work has investigated the effects of Brassica vegetables on lactobacilli, or the effects of GSLs on the bacterial community of the human gut as a whole.
REC name
East of England - Cambridgeshire and Hertfordshire Research Ethics Committee
REC reference
14/EE/1078
Date of REC Opinion
18 Sep 2014
REC opinion
Further Information Favourable Opinion