PhD Study : An investigation into the prebiotic potential of fibre derived from sustainably sourced Laminaria digitata and its potential impact on metabolic syndrome

Summary

The colonic microbiota is a relatively stable and balanced ecosystem containing 1014 bacteria with each bacteria species possessing an established ecological and nutritional niche. Disruption in the balance of the colonic bacteria composition or activity within the established microbiota (dysbiosis) has been implicated as a potential contributory factor in the pathogenesis of a range of conditions including obesity, type 2 diabetes and cardiovascular disease (Tilg et al. 2014). There is increasing interest in identifying novel dietary strategies to manipulate the composition and metabolism of the microbiota to prevent the progression of dysbiosis associated with chronic disease.

The use of fermentable fibres to modify the microbiota is one approach that has been extensively investigated and there is a need to identify novel fibres (Everard et al. 2013) The high fibre content of seaweeds alongside the evidence to support a role for seaweed consumption in the reduced incidence of metabolic complications such as obesity, dyslipidaemia and type II diabetes (Brown et al. 2013) makes it a plausible candidate as a potential source of fermentable fibres. In vitro studies have demonstrated that the crude extract of Laminaria digitata (LD) can be effectively fermented however, there is a need to investigate the efficacy of food grade LD crude extract in human intervention trials.

This project aims to isolate polysaccharide rich extract from harvest rope cultured LD and assess its fermentability in vitro and subsequently determine its efficacy on markers of health in human intervention trials.

Study 1: Production and characterisation of polysaccharide extract This process will involve: extraction, desalination (membrane filtration and electrodialysis), ethanol precipitation, and spray drying to produce a food grade extract and subsequent nutritional analysis for macronutrients and micronutrients. The crude extract will also undergo depolymerisation treatment to produce low, medium and high molecular weight extracts.

Study 2: Product development and organoleptic testing The LD polysaccharides extract candidates (Untreated LD polysaccharide spray dried extract; low/medium/high MW depolymerised LD polysaccharide spray dried extracts) will be incorporated into a range of foods and produced for sensory analysis and associated focus groups.

Study 3: Prebiotic assessment of functional food using batch culture fermenter systems. The fermentability of the final LD polysaccharide extract enriched food product will be assessed following simulated in vitro digestion using the new 24 vessel batch culture system which will facilitate high throughput analysis on the efficacy of the product. Samples will be collected and the short chain fatty acids (GC-FID) and changes in microbiota composition (next generation sequencing).

Study 4: An investigation into the impact of consuming LD polysaccharide extract enriched food product on markers of metabolic syndrome. This randomised placebo controlled crossover human intervention study will investigate the effect of consuming seaweed polysaccharide enriched food on faecal microbiota composition and associated metabolites and faecal short chain fatty acids. to investigate changes pertinent to biomarkers of metabolic syndrome, including: lipid status (cholesterol and triglycerides), inflammatory status (C-reactive protein and cytokine profile) and markers of glycaemic control (fasting glucose).

References:

Tilg, H. and Moschen, A.R., 2014. Microbiota and diabetes: an evolving relationship. Gut, 63(9), pp.1513-1521.

Everard, A. and Cani, P.D., 2013. Diabetes, obesity and gut microbiota. Best practice & research Clinical gastroenterology, 27(1), pp.73-83.

Essential criteria

Applicants should hold, or expect to obtain, a First or Upper Second Class Honours Degree in a subject relevant to the proposed area of study.

We may also consider applications from those who hold equivalent qualifications, for example, a Lower Second Class Honours Degree plus a Master’s Degree with Distinction.

In exceptional circumstances, the University may consider a portfolio of evidence from applicants who have appropriate professional experience which is equivalent to the learning outcomes of an Honours degree in lieu of academic qualifications.

• Sound understanding of subject area as evidenced by a comprehensive research proposal

Desirable Criteria

If the University receives a large number of applicants for the project, the following desirable criteria may be applied to shortlist applicants for interview.

• First Class Honours (1st) Degree
• Masters at 65%
• Research project completion within taught Masters degree or MRES
• Practice-based research experience and/or dissemination
• Experience using research methods or other approaches relevant to the subject domain
• Work experience relevant to the proposed project
• Publications - peer-reviewed
• Experience of presentation of research findings
• A comprehensive and articulate personal statement
• Relevant professional qualification and/or a Degree in a Health or Health related area

Funding and eligibility

The University offers the following levels of support:

Vice Chancellors Research Studentship (VCRS)

The following scholarship options are available to applicants worldwide:

• Full Award: (full-time tuition fees + £19,000 (tbc))
• Part Award: (full-time tuition fees + £9,500)
• Fees Only Award: (full-time tuition fees)

These scholarships will cover full-time PhD tuition fees for three years (subject to satisfactory academic performance) and will provide a £900 per annum research training support grant (RTSG) to help support the PhD researcher.

Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Please note: you will automatically be entered into the competition for the Full Award, unless you state otherwise in your application.

Department for the Economy (DFE)

The scholarship will cover tuition fees at the Home rate and a maintenance allowance of £19,000 (tbc) per annum for three years (subject to satisfactory academic performance).

This scholarship also comes with £900 per annum for three years as a research training support grant (RTSG) allocation to help support the PhD researcher.

• Candidates with pre-settled or settled status under the EU Settlement Scheme, who also satisfy a three year residency requirement in the UK prior to the start of the course for which a Studentship is held MAY receive a Studentship covering fees and maintenance.
• Republic of Ireland (ROI) nationals who satisfy three years’ residency in the UK prior to the start of the course MAY receive a Studentship covering fees and maintenance (ROI nationals don’t need to have pre-settled or settled status under the EU Settlement Scheme to qualify).
• Other non-ROI EU applicants are ‘International’ are not eligible for this source of funding.
• Applicants who already hold a doctoral degree or who have been registered on a programme of research leading to the award of a doctoral degree on a full-time basis for more than one year (or part-time equivalent) are NOT eligible to apply for an award.

Due consideration should be given to financing your studies. Further information on cost of living