We found significant differences between control lean and obese rats and between control and RE-supplemented animals suggesting important differences in the production, absorption and metabolism of these metabolites between the two types of rats. ICG-001 microbiota and SCFA metabolism differences between the lean and obese Zucker rats may be essential to explain the different metabolic and inflammatory response of the animals to the RE and warrant further research. Other plant extracts rich in bioactive compounds, polyphenols themselves and/or their derived metabolites have been shown to confer some of the effects attributed to prebiotics. A pomegranate extract, rich in punicalagin and ellagic acid, increases caecum content and Bifidobacterium and reduces serum cholesterol and the expression of inflammatory markers in mice adipose tissue and, both a pomegranate extract and its main microbiota-derived metabolite urolithin increase the counts of fecal Bifidobacterium, Lactobacillus and Clostridium spp. and decrease inflammatory markers in the rat. Wild blueberry, green tea extracts and resveratrol are all able to increase counts of Lactobacillus and/or Bifidobacterium. Although some of these plant products need to be fully characterized to determine or exclude the presence of prebiotic fiber, these results and our results show that plant bioactive compounds from different origins and molecular composition or their derived metabolites are able to modify gut microbiota composition and to promote beneficial changes with an impact into the host metabolism and inflammatory response. It is conceivable that plant food bioactive compounds may gradually be considered or classified as ‘prebiotics’ or as compounds with some ‘prebiotic effects’. The latest prebiotic concept may need to be expanded in the future to include these other food components, even though they are not necessarily fermented by the microbiota. Bioactive-enriched plant derived products constitute an additional strategy to combat metabolic disorders and associated inflammatory processes but further research is required to fully characterize these products, to unravel their mechanisms of action and to demonstrate their effects in humans. In conclusion, a RE enriched in bioactive diterpenoids and that exhibits body weight reducing effects and beneficial metabolic and inflammatory properties has also a significant impact on the microbiota composition and b-glucosidase activity in the caecum of female Zucker rats and increases fiber fecal excretion. Importantly, the presence of a recessive mutation in the leptin receptor has a critical effect on the microbiota caecum composition and on the host response to the consumption of RE. A limitation of our study is that only a few groups of bacteria members of the Firmicutes, Bacteroidetes, and Actinobacteria phyla were investigated and that they constitute a small % of the total bacteria.