There is increasing evidence that non-nutrient components of fruit and vegetables (FAV) may have key roles in providing the health benefits associated with diets rich in FAV. The main thrust of my research examines the possibility that phytochemicals in plant foods can influence human health. The focus has been on soft fruit, particularly on polyphenols in berries, as there is already evidence for the effectiveness of these components from other foods and beverages and berries are a particularly rich and palatable source.
My research has four main overlapping and interdependent areas:
To accrue evidence that berry phytochemicals have bioactivities that can influence human health or mitigate disease progression, I have initiated collaborations with a range of biomedical experts who have relevant model systems for cardiovascular health, neurodegeneration, diabetes, and cancers. These model systems range from in vitro enzyme screens, ex vitro cell or tissue studies to animal or human trials. I also developed key in-house screens and assays. In each case, extracts with closely defined compositions have been used and the studies include analysis of the metabolic fate of the components to define the mechanisms of action and the candidate active ingredients. In human trials, bioavailability studies of the levels of metabolites in blood, urine and faeces have been completed.
Through these studies, I have confirmed that different polyphenol components from berries can have different effects in different model systems and that overall efficacy is often decided by a combination of bioactivity, stability and longevity/bioavailability in the system. These cross-disciplinary collaborations have led to close associations particularly with the University of Ulster and the University of Dundee. These approaches are currently being applied to studies on Alzheimer’s disease through the EU-funded BrainHealthFood [2] project.
Along with Ilka Abreu [3] and Sean Connor, I have established novel MS based methods for following polyphenol diversity. This has enabled us to begin to link polyphenol inheritance to the genetic maps being developed for raspberry and blackcurrant by the Genetics Programme (with Rex Brennan [4] and Julie Graham [5]). Through this approach, we hope to enable accelerated breeding of improved varieties with elevated levels of healthy components. Importantly, I have also directed research to establish if environmental conditions influence polyphenol levels, which has informed us that certain genetic markers are consistently associated with enhanced polyphenol content across years with widely differing climatic conditions. The high-through-put methods developed have been employed to track the diversity of polyphenols from growing berries under different agronomic conditions, in different latitudes or after different processing methods with collaborators from across Europe (ClimaFruit Project [6]). These areas form part of the new programme of work planned for the Scottish Government.
I have also been involved in studies that correlate the metabolic and molecular changes associated with aspects of food quality. For example, through close working with Mark Taylor [7] and Rob Hancock [8] and collaborators from the University of Colorado, we correlated changes in metabolite profiles and gene expression in coloured and non-coloured potato tuber tissues.
With industrial and University partners, I have applied our analytical capacities to solve problems associated with berry flavour, juice manufacture and the effects of processing and cooking on bioactive components from diverse sources such as seaweeds and oats (see Quoats project [9]).
I have also applied expertise in cell wall chemistry and biochemistry to studies on potato flavour and texture led by Mark Taylor within PPFQ. We are assessing the genetic and biochemical basis of potato tuber texture by comparing differences in textural properties between Solanum tuberosum and Solanum phureja varieties. These varieties have consistent year-on-year differences in texture and cooking properties, which are correlated with differences in cell wall structure and cohesiveness. We have identified that these differences are mainly associated with subtle differences in pectin structure and localisation which directly influence cell-to-cell adhesion. Indeed, microarray analysis has identified candidate genes involved in pectin methylation and decoration whose expression has subsequently been manipulated to provide evidence for their involvement in the textural traits.
This work has involved collaborations with British Universities including Bath, Glasgow, Ulster, Dundee, Reading, Abertay, Queen Margaret, Newcastle, Sheffield Hallam, Strathclyde, Aberystwyth, University of the Highlands and Islands and St Andrews. International collaborations are in place with scientists from Universities and Research Institutes in, for example, Germany, Italy, Bulgaria, Spain, Norway, Sweden, Denmark, France, Holland, Ireland, Portugal, USA and New Zealand. We also have a number of research partners in UK and European companies.
Links:
[1] https://orcid.org/0000-0002-2285-0124
[2] http://cordis.europa.eu/fetch?CALLER=FP7_PROJ_EN&ACTION=D&DOC=5&CAT=PROJ&QUERY=012dc50c89ec:cfb2:70322035&RCN=94145
[3] https://www.hutton.ac.uk/ilka-abreu
[4] http://rex-brennan
[5] https://www.hutton.ac.uk/julie-graham
[6] http://www.northsearegion.eu/ivb/projects/details/&tid=122
[7] https://www.hutton.ac.uk/mark-taylor
[8] https://www.hutton.ac.uk/robert-hancock
[9] http://www.quoats.org/