Supplementation with Chlorella vulgaris, Chlorella protothecoides, and Schizochytrium sp. increases propionate‐producing bacteria in in vitro human gut fermentation

Abstract

BACKGROUND Gut microbiota are major contributors to host metabolism and are considered as potential targets of novel therapeutics. Microalgae have a strong potential for use as prebiotics because they are a rich source of proteins, fatty acids, fiber, and minerals for nutritional supplementation in humans. Nevertheless, there has been insufficient research into the effect of microalgae on gut microbiota. To investigate the effects of three edible microalgae (Chlorella vulgaris, Chlorella protothecoides, and Schizochytrium sp.) on gut microbiota, simulated digestion and colonic fermentation were examined. RESULTS Following in vitro digestion, the microalgae displayed different levels of bioaccessibility and the nutrient analysis revealed that unabsorbed nutrients during the digestion process could be used for colonic fermentation. Following colonic fermentation, the control, inulin, and microalgae groups displayed different metabolite tendencies when investigated with nuclear magnetic resonance (NMR) spectroscopic analysis. In particular, microalgae supplementation increased the proportion of propionate in the colonic culture (control: 19.14%, Inulin: 18.38%, C. vulgaris: 25.80%, C. protothecoides: 25.46%, and Schizochytrium sp.: 25.56%). Microbial profiling analysis using 16S rRNA gene sequencing also disclosed that the relative abundance of Bacteroides (control: 1.91%, inulin: 2.61%, C. vulgaris: 14.77%, C. protothecoides: 11.17%, and Schizochytrium sp.: 5.51%) and Dialister (control: 0.08%, inulin: 2.06%, C. vulgaris: 6.79%, C. protothecoides: 4.45%, and Schizochytrium sp.: 4.48%), involved in propionate metabolism increased more than in the inulin group. CONCLUSION Our findings suggest the potential use of microalgae as a functional food to increase propionate generation because propionate has been reported to be effective in weight loss and the inhibition of pathogen infection. © 2020 Society of Chemical Industry

Influence of Chlorella vulgaris on growth, digestibility and gut morphology and microbiota of weaned piglet

“…Microbiome results suggest that the use of C. vulgaris in piglet feeding, in combination or not with enzymes, significantly affects the faecal bacterial structure of piglets, as previously observed in humans 14 . In addition, C. vulgaris incorporation supplemented with 0.005% Rovabio increased the relative abundance of Lactobacillus and Oscillospira .…”

Assessment of the Effects of Edible Microalgae in a Canine Gut Model

“…We selected these four species because they currently represent the microalgae of greatest interest in the food and feed sector [ 8 , 13 ]. We hypothesized that composition and metabolism of canine fecal microbiota would be influenced by microalgae supplementation; particularly, we expected an increase concentration of the three major SCFA (acetate, propionate and butyrate), in accordance with previously in vitro cited studies [ 31 , 32 ], and higher concentration of microbial species known to be SCFA producers (i.e., Ruminococcaceae, Clostridium cluster XIV, Turicibacter spp., C. leptum, C. coccoides) [ 37 ]; in addition, we assumed that microbial species thought to have undesired influences on canine gut health would decrease. Lastly, we hypothesized a decrease of metabolites deriving from bacterial proteolysis (ammonia, BCFA, biogenic amines) due to the enhanced saccharolytic activities of bacterial populations.…”

“…Microalgae biomass showed a selective stimulation of beneficial microorganisms and inhibition of undesired bacteria on colonic microbiota. A previous study conducted by Jin et al [ 32 ] reported that supplementation with Chlorella vulgaris and other microalgae increased propionate-producing bacteria in an in vitro human gut fermentation model. According to the previously cited studies, in order to evaluate the effects of microalgae on intestinal microbiota, it is appropriate to use an in vitro digestion procedure and subsequently undergo the digested biomass to colonic in vitro fermentation, with the aim to examine the potential microbiota modulation activities of microalgae [ 31 , 32 ].…”

An in vitro batch fermentation protocol for studying the contribution of food to gut microbiota composition and functionality

“…Other authors also used this protocol to study the modulatory effect of polyphenols and sesquiterpene lactones from artichoke heads 22 or Chlorella spp. 23 on gut microbiota composition and functionality.…”