The Impact of Long‐Term Intake of Phenolic Compounds‐Rich Grape Pomace on Rat Gut Microbiota

Abstract

The aim of this work is to evaluate the impact on the rat microbiota of long-term feeding with phenolic compounds (PC) rich grape pomace extracts. Thirty, 2-mo-old rats, were divided into 5 groups. Four groups were treated with different concentrations of PC (2.5, 5, 10, and 20 mg/kg/d diluted in 0.1% DMSO), and 1 group received 0.1% Dimethyl Sulfoxide (DMSO) alone (control group). The daily treatment lasted 14 mo. Major phenolic compounds constituents were characterized by the high-performance liquid chromatography and free radical scavenging capacity was measured by means of the DPPH assay. Fecal samples from young rats (2-mo old), and rats daily fed with PC or DMSO were collected at 6 and 14 mo posttreatment. The gut microbiota composition was analyzed by quantitative polymerase chain reaction. Bifidobacterium was significantly higher in the groups PC 2.5 and PC 5 than in control and young rats. Lactobacillus decreased with time in all treated and untreated groups. Bacteroides, Clostridium leptum subgroup (Clostridium cluster IV), and Enterococcus were not significantly changed by PC at any concentration when compared to control; nevertheless, after 14 mo of treatment all concentrations of PC abolished the increase of Clostridium sensu stricto (cluster I) (Clostridium Cluster I) observed in the control group when compared to young rats. PC do modulate selectively rat gut microbiome to a healthier phenotype in long-term feeding rats, and could counteract the adverse outcomes of aging on gut bacterial population.Keywords: aging, gut microbiota, phenolic compoundsPractical Application: This research shows that phenolic-rich grape pomace extracts exhibiting a high antioxidant activity, selectively modulate rat gut microbiota to a healthier phenotype within age in a long-term feeding rats.

Effects of Dietary Grape Seed Meal Bioactive Compounds on the Colonic Microbiota of Weaned Piglets With Dextran Sodium Sulfate-Induced Colitis Used as an Inflammatory Model

“…Similarly, herein, the Firmicutes phylum was decreased in a significant way (p < 0.05) under DSS effect and was not affected by the addition of GSM into the diet in a significant way. Clostridium, Roseburia, Acidaminococcus, and Escherichia are often cited as the genera usually found in abundance in irritable bowel diseases (48)(49)(50)(51)(52) and DSS treatment, while Lactobacillus, Prevotella, and Faecalibacterium are cited as negatively impacted or inversely correlated with the severity of the disease (33,(53)(54)(55)(56). Indeed, in our work, Roseburia, Megasphera, and CF231 increased significantly under the DSS presence while Lactobacillus registered a significant decrease overall.…”

“…The observed reduction in the abundance of Lactobacillus spp. in pigs with DSSinduced inflammation or pigs with an intake of GSM diet and dramatically in DSS+GSM groups might be associated with the negative impact that the DSS has on this genus (55) as well as the interaction between Lactobacillus, the type of phenolic compounds and their concentration as described in the scientific literature (56,60). However, the findings are controversial.…”

“…The grape seed extract was also shown to inhibit the growth of Streptococcus thermophilus, Bifidobacterium lacticus, Lactobacillus fermentum, and acidophilus due to their perceived sensitivity to the polyphenol fraction flavan-3-ols (63). Nevertheless, the activity of some biological compounds could be masked by that of others, which constrain the understanding of the exact synergistic effect that could happen (56). In contrast, a significantly higher level of Prevotella belonging to Bacteroidetes phylum was observed in our study being stimulated by the interaction between DSS and GSM.…”

Long‐term intake of phenolic compounds attenuates age‐related cardiac remodeling

“…The corresponding by‐products were stored at −20°C until use. Once defrosted at room temperature, PC extraction and characterization were performed as previously described (Chacar et al, ). Briefly, the PC were extracted from grape pomace extracts via a solid–liquid extraction, and then, the solutions were spray‐dried and we obtained a powder consisting of a pure mixture of PC.…”

Coffee, type 2 diabetes and pancreatic islet function – A mini-review

“…Absorption and metabolism of phenolic acids also take place in the large intestine, where the microbiota plays an important role in further catabolizing and modifying the precursor compounds (Anhê et al, 2013;Olthof, Hollman, Buijsman, van Amelsvoort, & Katan, 2003). Some in vitro and in vivo studies have shown the potential prebiotic effects of phenolic acids to increase the population of healthy beneficial bacteria such as bifidobacteria whilst decreasing adverse populations (Chacar et al, 2018;Duncan et al, 2016;Xie et al, 2017). Thus the resulting metabolic end products from the large intestine are likely to be quantitatively more important contributors to the circulating levels of physiologically relevant metabolites than those from the small intestine and contribute to a later peak of CGAs in the blood (Gonthier et al, 2003;Renouf et al, 2010;Stalmach et al, 2014).…”