Exploring the therapeutic potential of porphyran extracted from Porphyra haitanensis in the attenuation of DSS-induced intestinal inflammation.

Ulcerative colitis is a chronic, spontaneous inflammatory bowel disease that primarily affects the colon. This study aimed to explore how Porphyra haitanensis porphyran (PHP) modulates the immune response and the associated mechanisms that alleviate dextran sulphate sodium-induced colitis in mice. Histological assessments via H&E staining and AB-PAS staining revealed that PHP intervention partially restored the number of goblet cells and improved intestinal mucosal function. Immunohistochemical and Western blot analyses of claudin-1, occludin, and MUC-2 demonstrated that PHP could repair the intestinal barrier and reduce colon damage by upregulating the expression of these proteins. PHP intervention was associated with a decrease in pro-inflammatory cytokine expression and an increase in anti-inflammatory cytokine expression. Moreover, the expression of proteins involved in intestinal immune homing, such as CCR-9, CCL-25, MAdCAM-1, and α4ß7, was significantly suppressed in response to PHP treatment. Conversely, PHP upregulates the expression of CD40 and TGF-ß1, both of these can promote healing and reduce inflammation in the gut lining. This study demonstrates that PHP can ameliorate ulcerative colitis by enhancing the intestinal barrier and modulating immune responses. These findings offer valuable insights into the potential utility of P. haitanensis as a promising natural product for managing ulcerative colitis.

Recent advances in marine algae oligosaccharides: structure, analysis, and potential prebiotic activities.

Marine algae contain abundant polysaccharides that support a range of health-promoting activities; however, the high molecular weight, high viscosity, and low solubility of marine algae polysaccharides (MAPs) limit their application in food, agriculture and medicine. Thus, as the degradation products of MAPs, marine algae oligosaccharides (MAOs) have drawn increasing attention. Most MAOs are non-digestible by digestive enzyme in the human gastrointestinal tract, but are fermented by bacteria in the gut and converted into short-chain fatty acids (SCFAs). MAOs can selectively enhance the activities of some populations of beneficial bacteria and stimulate a series of prebiotic effects, such as anti-oxidant, anti-diabetic, anti-tumour. However, the exact structures of MAOs and their prebiotic activities are, to a large extent, unexplored. This review summarizes recent advances in the sources, categories, and structure analysis methods of MAOs, emphasizing their effects on gut microbiota and its metabolite SCFAs as well as the resulting range of probiotic activities.

Structural characteristics of Gracilaria lemaneiformis oligosaccharides and their alleviation of dextran sulphate sodium-induced colitis by modulating the gut microbiota and intestinal metabolites in mice.

Ulcerative colitis (UC) is a chronic lifetime disorder with a high incidence worldwide. A functional food-based method to prevent UC would be a good option for disease control. G. lemaneiformis oligosaccharides (GLOs) should have potent benefits for the gastrointestinal tract, based on in vitro fermentation assessed in our previous study. This study evaluated the therapeutic potential of GLOs in UC, as well as their possible mechanisms of action. The administration of GLOs was able to reduce the severity of dextran sulphate sodium-induced colitis by protecting mice from weight loss, reductions in colon length, inflammatory infiltration, and colon damage. Gut microbiota composition analysis showed that at the phylum level, GLOs could restore the composition of Bacteroidetes and decrease the level of Firmicutes. Consistently, it increased the contents of beneficial microbial metabolites and short-chain fatty acids in the mouse colitis model. In conclusion, GLOs could comprise a promising functional food strategy to alleviate UC symptoms.

Quantification of 3,6-anhydro-galactose in red seaweed polysaccharides and their potential skin-whitening activity.

This study determined the composition of the monosaccharide, 3, 6-anhydrogalactose (AnGal), in red algae and explored the potential whitening activity of the extract. Using gas chromatography-mass spectrometry (GC-MS), the AnGal composition of six different species of red seaweed (Porphyra haitanensis, Gracilaria chouae, Gracilaria blodgettii, Gracilaria lemaneiformis, Eucheuma galetinae, and Gelidium amansii) was successfully analyzed, revealing molar ratios ranging from 1.0:1.0 to 1.0:3.1 of AnGal and galactose (Gal), respectively. Employing the tyrosinase inhibition assay, the skin-whitening effect of AnGal red seaweed polysaccharides was determined. Polysaccharides from P. haitanensis, G. chouae, and G. blodgettii as well as their degradation products showed higher tyrosinase inhibitory activity (inhibition rates 24.2-26.8%). These results suggest that the GC-MS approach could conveniently be used in quality control or for the quantitative determination of AnGal and Gal in red seaweed polysaccharides as well as exploring their potential application in cosmetic and functional food products. The findings here exhibited that red seaweed polysaccharides and their degradation products were potential ingredients for cosmeceutical industries.