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In vitro evaluation of the prebiotic activity of a pectic oligosaccharide-rich extract enzymatically derived from bergamot peel


The prebiotic effect of a pectic oligosaccharide-rich extract enzymatically derived from bergamot peel was studied using pure and mixed cultures of human faecal bacteria. This was compared to the prebiotic effect of fructo-oligosaccharides (FOS). Individual species of bifidobacteria and lactobacilli responded positively to the addition of the bergamot extract, which contained oligosaccharides in the range of three to seven. Fermentation studies were also carried out in controlled pH batch mixed human faecal cultures and changes in gut bacterial groups were monitored over 24 h by fluorescent in situ hybridisation, a culture-independent microbial assessment. Addition of the bergamot oligosaccharides (BOS) resulted in a high increase in the number of bifidobacteria and lactobacilli, whereas the clostridial population decreased. A prebiotic index (PI) was calculated for both FOS and BOS after 10 and 24 h incubation. Generally, higher PI scores were obtained after 10 h incubation, with BOS showing a greater value (6.90) than FOS (6.12).

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We would like to thank Grant Colder (John Innes Centre, Norwich, UK) for his help in microscopy. We gratefully acknowledge the help provided by Yvan Lemarc (Institute of Food Research) with the statistic analyses. This research was funded by the Biotechnology and Biological Research Sciences Council (UK), by the University of Messina (Italy) and by Ministero dell’Universita’ e della Ricerca, Italy (project no. 12930).

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Correspondence to A. Narbad.

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Mandalari, G., Nueno Palop, C., Tuohy, K. et al. In vitro evaluation of the prebiotic activity of a pectic oligosaccharide-rich extract enzymatically derived from bergamot peel. Appl Microbiol Biotechnol 73, 1173–1179 (2007). https://doi.org/10.1007/s00253-006-0561-9

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  • Fructo-oligosaccharides
  • Bergamot oligosaccharides
  • Prebiotics
  • Pectic
  • Lactobacilli
  • Bifidobacteria