RESUMEN
Laminaria japonica is rich in alginate (Alg) and galactofucan (GF) which have both been reported to regulate gut microbiota composition. To reveal the effect of L. japonica on human gut microbiota, the fecal microbiota of 12 volunteers before and after 14-day L. japonica intake was sequenced and compared, and the capabilities of the gut microbiota to utilize Alg and GF were also investigated. The 16S rRNA gene sequencing results demonstrated that Firmicutes/Bacteroidetes ratio could be balanced by L. japonica supplementation. The ability of gut microbiota to utilize Alg was significantly enhanced by L. japonica supplementation. Furthermore, the multiple linear regression analysis suggested that bacteria from Bacteroidaceae and Ruminococcaceae were positively correlated with Alg utilization while those from Erysipelotrichaceae, Bacteroidaceae, and Prevotellaceae participated in GF degradation. Moreover, the production of acetic acid and the total short-chain fatty acids (SCFAs) in fermentation were consistent with the consumption of Alg or GF, and propionic acid content was positively correlated with Alg consumption. In addition, the percentage of monosaccharides in the consumed GF after the fermentation suggested that gut microbiota from individuals could consume GF with different monosaccharide preferences. These findings shed a light on the impacts of dietary L. japonica on human health.
RESUMEN
Using a sulfated polysaccharide from the gonad of pacific abalone (AGSP), a novel polysaccharide-Fe(III) complex, AGSP-Fe(III), was synthesized, and it was characterized by a series of methods including ultraviolet-visible (UV-vis) spectroscopy, Fourier transform-infrared (FT-IR) spectroscopy, circular dichroism (CD) spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). The results showed that AGSP-Fe(III) was formed by the Fe-O bond between sulfate, carboxyl, and hydroxyl groups in AGSP and Fe, its particle size reached a maximum of 200 nm after aggregating, and its surface morphology presented relatively regular columnar or spherical. Moreover, the iron release of AGSP-Fe(III) during simulated gastrointestinal digestion was exhibited, and its good iron supplementary efficiency was also shown using Caco-2 cells. In addition, compared to FeCl3, AGSP-Fe(III) showed better solubility and stability in the presence of polyphenol/trypsin. The present study demonstrated the potential of AGSP-Fe(III) as a novel iron supplement.
RESUMEN
Antibiotic treatment, as an important therapeutic intervention, can cause damage to the host microbiome and the intestinal mucosal barrier. In order to find a way to alleviate the side effects of antibiotics, the present study investigated the effects of fucoidan (ANP) isolated from Ascophyllum nodosum on gut microbiota dysbiosis and colonic inflammation induced by ciprofloxacin-metronidazole (CiMe) in C57BL/6J mice. Our results showed that dietary ANP prevented colon shortening, alleviated the colonic tissue damages, and partially reversed the alteration of gut microbiota by increasing the abundance of potentially beneficial bacteria, e.g., Ruminococcaceae_UCG_014 and Akkermansia and decreasing the abundance of harmful bacteria, e.g., Proteus and Enterococcus. ANP also suppressed the overproduction of TNF-α, IL-1ß, and IL-6 and promoted the expression of IL-10. In addition, ANP reversed the decreased production of short-chain fatty acids in CiMe-treated mice. Furthermore, correlation analysis indicated the presence of critical gut microbiota, which played important roles in reducing the inflammation-related indices. Thus, the present study suggests that fucoidan isolated from Ascophyllum nodosum is effective in providing protection against the negative effects of antibiotics on gut microbiota and colonic health.