Rights: University of Waikato Published 1 July 2011 Download

Dr Juliet Ansell is a Science Group Leader at Plant & Food Research, Palmerston North. Juliet outlines the research project she leads that investigates the interactions between food, gut bacteria and health. There are 3 parts to the research involving in vitro work, animal models and human clinical trials.


Dr Juliet Ansell

We’re really interested in the interactions that go on between food, bacteria and our own health. One of the exciting things that we’ve found recently is that foods can have an impact on the immune system via the microbes.

A lot of work that we do in the labs is in vitro work, and that’s when we simulate what’s happening in our bodies, so the digestion mouth to stomach, the fermentation in the large bowel. We’re trying to get information about what’s happening to different foods and what effects those might be having in the body.

Secondary focus is using animal models to look at whether what we found in vitro really does happen. The whole body is a hugely complex system so you can really only test that in a whole-animal system. Then the third area of human clinical trials, we’re feeding people and then measuring what’s happening in terms of their gut health.

One of the major difficulties with mimicking the large intestine is that, in real life, it’s inside our bodies. It’s completely anaerobic in parts – that means there’s no oxygen there. We use things called anaerobic chambers – a whole big chamber where you actually put your hands in and work with it – and we have mini anaerobic chambers – small shoebox-size boxes where you can put things in and you also put in a little sachet that quenches all the oxygen out of the atmosphere. So it’s sort of creating an anaerobic environment.

So we’ll do work in vitro where we’re mimicking the large intestine, and then we’ll also carry out an animal trial, a human feeding trial and collect faecal samples and look at how those 2 things relate. It’s really, really expensive to carry out human clinical trials, so when you get to the stage where you want to do a human clinical trial, you want to be sure that you’ve got your 1 thing that you want to test. But to get to that point, you need to do a whole lot of screening in vitro. In vitro screening is cheap, you can test lots and lots of things and get a really good idea. It’s like a funnel process.