Enzymatic Preparation of Low-Molecular-Weight Laminaria japonica Polysaccharides and Evaluation of Its Effect on Modulating Intestinal Microbiota in High-Fat-Diet-Fed Mice

Abstract

Recent studies have shown that seaweed polysaccharides can ameliorate high-fat-diet (HFD)-induced metabolic syndromes associated with the regulatory function of gut microbiota. However, kelp, a natural source of seaweed polysaccharides, is highly viscous, making it difficult to prepare dietary fiber by simple degradation. Therefore, we developed a novel method of preparing low-molecular-weight polysaccharides from Laminaria japonica by combining high-pressure pretreatment and composite enzymatic degradation and evaluated the obesity prevention activity of these polysaccharides. Seaweed L. japonica polysaccharides (SJP) were rapidly utilized by the human fecal microbiota in vitro, resulting in the generation of short-chain fatty acids (SCFAs), specifically acetate and propionate. The in vivo effects of SJP on the intestinal microbiota were also investigated using HFD-fed C57BL/6J mice. SJP reduced weight gain and fat deposition in HFD-fed mice and increased the concentration of total SCFAs, including acetate, propionate, and butyrate in the feces. SJP ameliorated HFD-induced gut microbiota dysbiosis, resulting in increased abundance of Faecalibaculum, Romboutsia, and Clostridium sensu stricto 1 and decreased abundance of Blautia and Lactobacillus. Further, SJP enhanced the abundance of Akkermansia muciniphila in mice provided with HFD and normal chow. Single-strain culture experiments also revealed that SJP promoted the growth of A. muciniphila. This study highlights the potential use of SJP, prepared using composite enzymatic degradation (cellulase and recombinant alginate lyase), in preventing obesity and restoring intestinal homeostasis in obese individuals.

Efficacy and Mechanism of Pueraria lobata and Pueraria thomsonii Polysaccharides in the Treatment of Type 2 Diabetes

“…The pathways involved in the microbiota affected by T2D mellitus were the same as those involved in the metabolites affected by T2D mellitus in serum metabolomics. The significantly increased Romboutsia bacteria content after GG polysaccharide treatment was negatively correlated with tauroursocholic acid, The significantly reduced Klebsiella content after FG polysaccharide treatment was positively correlated with uric acid, Romboutsia [ 24 ], and Klebsiella [ 10 ], which are qualities associated with T2D. These results indicated that T2D affected the metabolic environment in the body by affecting the gut microbiota, and the GG and FG polysaccharides were able to ameliorate the metabolites in the serum by regulating the gut microbiota.…”

Seaweed polysaccharide relieves hexavalent chromium-induced gut microbial homeostasis

“…After acclimatization for 3 days, these mice were randomly divided into three groups namely control group (Con), Cr (VI)-induced group (Cr), seaweed polysaccharide treatment group (SP, 200 mg/kg). The dosage of seaweed polysaccharide and Cr (VI) refers to the previous research with slight improvements ( Ben et al, 2016 ; Fu et al, 2021 ). The proportion of male and female in each groups was 1:1.…”

“…Numerous studies indicated that seaweed polysaccharide has anti-inflammatory, antiviral, immunomodulatory and anti-tumor effects ( Lomartire and Goncalves, 2022 ). Moreover, recent research on seaweed polysaccharide also showed its vital roles in the gastrointestinal disease and improve antioxidant ability ( Fu et al, 2021 ). Although increasing evidence showed the positive role of seaweed polysaccharide on the host health, it remains unclear whether seaweed polysaccharide can alleviate gut microbial imbalance caused by hexavalent chromium.…”