Bob Rastall

Affiliation: Professor of Food Biotechnology in the Department of Food Biosciences, The University of Reading, UK

Short Biography:

Professor Bob Rastall is Professor of Food Biotechnology in the Department of Food and Nutritional Sciences at the University of Reading in the UK. He has been involved in prebiotic oligosaccharide research for more than 20 years. His interests are predominantly in the structure-function relationships in prebiotics and the generation of novel candidate prebiotics using biotechnological approaches. Utilisation of agrifood processing wastes for this purpose is a particular current focus.
Previous posts: 1987-1993: University of Westminster, London, UK. During this time I worked on two research projects: “The development of enzymatic synthesis protocols to manufacture oligosaccharides as phytoalexin elicitors” and “Bioinformatics of complex oligosaccharide sequences”
Education: 1980-1984: BSc Applied Biology, The University of Greenwich, London, UK. Specialising in microbiology, biochemistry and biotechnology. Final year research project on outer membrane proteins of Pseudomonas morsprunorum.
1984-1987: PhD “The cell surface biochemistry of Erwinia amylovora”. 

Current Research: 

My research at this time focussed on the cell surface carbohydrates of this pear tree pathogen, attempting to identify the structure of the cell surface polysaccharides elaborated by the bacterium and their postulated role in virulence in planta.

Research activities:
i) Development of manufacturing technologies for functional oligosaccharides based on enzymes. This has involved using glycosidases to synthesise novel candidate prebiotics from simple oligosaccharides such as sucrose and lactose. By rational choice of synthetic catalyst it may be possible to produce highly targeted oligosaccharide preparations to stimulate populations and activities of specific beneficial microbes. Control of enzymatic synthesis conditions may also allow the control of molecular weight distribution, possibly affecting the kinetics of fermentation in the gut.

ii) Manufacture of functional oligosaccharides from waste plant biomass sources. This has involved the use of glycanases and physical treatment approaches to perform controlled hydrolysis of plant polysaccharides. Polysaccharides such as arabinoxylans, pectins, galactans and arabinogalactans can be obtained in large quantities from a range of agri-food wastes. Selection of the most appropriate enzyme and control of hydrolysis conditions allows production of novel oligosaccharides with defined molecular weight distributions.

iii) Evaluation of structure-function relationships in fermentable carbohydrates. Whilst our ability to manufacture novel oligosaccharides has grown significantly we still have scant understanding of the relationship between carbohydrates structure and the metabolism of these structures by the human gut microbiota. Such an understanding of structure-function relationships will allow rational decisions over which structures should be developed further into products and will open up new avenues in functional carbohydrates, such as the targeting of specific metabolite production by the microbiota. This work involves the use of in vitro models of human gut carbohydrate fermentation with molecular microbiological methods and metabonomic analysis of fermentation products to probe the ecological and metabolic consequences of feeding carbohydrates with a range of structures.

iv) Rational development of synbiotics. A combination of the probiotic and prebiotic approaches, synbiotics offer a lot of potential for management of gut disorders. Most studies on synbiotics have been carried out on mixtures designed by purely commercial considerations. If, however, we are to fully exploit the potential of the synbiotic approach, we need a more rational design process. Consequently we are investigating the interaction between probiotics and carbohydrate fibres in the context of health benefits and using the synthesis technologies described above to use probiotics to synthesise their own prebiotics.

Recent publications

Marina Diez-Municio; Sofia Kolida; Miguel Herrero;Robert A. Rastall; F Javier Moreno (2015) In vitro faecal fermentation of novel oligosaccharides enzymatically synthesized using microbial transglycosidases acting on sucrose. Journal of Functional Foods (In Press)

Moniz P, Ho AL, Duarte LC, Kolida S, Rastall RA, Pereira H, Carvalheiro F (2016) Carbohydr. Polym. Assessment of the bifidogenic effect of substituted xylo-oligosaccharides obtained from corn straw. Epub 2015. doi: 10.1016/j.carbpol.2015.09.046

Lamichhane S, Yde CC, Forssten S, Ouwehand AC, Saarinen M, Jensen HM, Gibson GR, Rastall R, Fava F, Bertram HC. (2014) Impact of dietary polydextrose fiber on the human gut metabolome. J Agric Food Chem. 62: 9944-51.

Sarbini SR, Kolida S, Deaville ER, Gibson GR, . (2014) Potential of novel dextran oligosaccharides as prebiotics for obesity management through in vitro experimentation. Br J Nutr. 112:1303-14.

Likotrafiti E, Tuohy KM, Gibson GR, . (2014) An in vitro study of the effect of probiotics, prebiotics and synbiotics on the elderly faecal microbiota. Anaerobe. 2014 27:50-5.

Childs CE, Röytiö H, Alhoniemi E, Fekete AA, Forssten SD, Hudjec N, Lim YN, Steger CJ, Yaqoob P, Tuohy KM, , Ouwehand AC, Gibson GR. (2014) Xylo-oligosaccharides alone or in synbiotic combination with Bifidobacterium animalis subsp. lactis induce bifidogenesis and modulate markers of immune function in healthy adults: a double-blind, placebo-controlled, randomised, factorial cross-over study. Br J Nutr. 24:1-12.

Ho AL, Carvalheiro F, Duarte LC, Roseiro LB, Charalampopoulos D, . (2014) Production and purification of xylooligosaccharides from oil palm empty fruit bunch fibre by a non-isothermal process. Bioresour Technol. 152:526-9.

Rodriguez-Colinas B, Kolida S, Baran M, Ballesteros AO, Rastall RA and Plou FJ. (2013) Analysis of fermentation selectivity of purified galacto-oligosaccharides by in vitro human faecal fermentation. Appl. Microbiol Biotechnol. 97:5743-52.

Osman A, Tzortzis G, Rastall RA, Charalampopoulos D. (2013) High Yield Production of a Soluble Bifidobacterial β-Galactosidase (BbgIV) in E. coli DH5α with Improved Catalytic Efficiency for the Synthesis of Prebiotic Galactooligosaccharides. J Agric Food Chem. 61 (9), pp 2213–2223.

Likotrafiti E, Tuohy KM, Gibson GR, Rastall RA. (2013) Development of antimicrobial synbiotics using potentially-probiotic faecal isolates of Lactobacillus fermentum and Bifidobacterium longum. Anaerobe. 20:5-13.

Sarbini, SR, Kolida, S, Gibson, GR, Rastall, RA. (2012) In vitro fermentation of commercial α-gluco-oligosaccharide by faecal microbiota from lean and obese human subjects. British Journal of Nutrition. 2:1-10.

Maneerat S, Lehtinen MJ, Childs CE, Forssten SD, Alhoniemi E, Tiphaine M, Yaqoob P, Ouwehand AC and Rastall RA (2013) Consumption of Bifidobacterium lactis Bi-07 by healthy elderly adults enhances phagocytic activity of monocytes and granulocytes Journal of Nutritional Science Volume 2 e44

Costabile, A., Fava, F., Roytio, H., Forssten, S.D., Olli, K., Klievink, J., Rowland, I., Ouwehand, A.C., Rastall, B., Gibson, G. and Walton, G. (2012) Impact of polydextrose on the faecal microbiota: a double-blind, crossover, placebo-controlled feeding study in healthy human subjects. British Journal of Nutrition. 108 pp. 471-481.

Walton, G., van den Heuvel, E., Kosters , M.H., Rastall, B., Tuohy, K. M. and Gibson, G. (2012) A randomised crossover study investigating the effects of galacto-oligosaccharides on the faecal microbiota in men and women over 50 years of age. British Journal of Nutrition. 107 pp.1466-1475.

Cardelle-Cobas, A., Agustín Olano, A., Corzo, N, Villamiel, M., Collins, M., Kolida, S. and Rastall, R.A. (2012) In Vitro Fermentation of Lactulose-Derived Oligosaccharides by Mixed Fecal Microbiota Journal of Agricultural and Food Chemistry. 60 pp. 2024-2032.

Osman, A., Tzortzis, G., Rastall, R. A. and Charalampopoulos, D. (2012) BbgIV is an important Bifidobacterium β-galactosidase for the synthesis of prebiotic galactooligosaccharides at high temperatures. Journal of Agricultural and Food Chemistry. 60 (3), pp 740–748

Hernandez-Hernandez, O., Sanz, M. L., Kolida, S., Rastall, B. and Moreno, F. J. (2011) In vitro fermentation by human gut bacteria of proteolytically digested caseinomacropeptide nonenzymatically glycosylated with prebiotic carbohydrates. Journal of Agricultural and Food Chemistry, 59 (22). pp. 11949-11955.