The Anti-oxidation Activity Of Sargassum Fusiforme Polysaccharide (SFPS) And Discussion On Its Effect On Anti-aging

Aging has always been an important direction for people to study,especially anti-aging study which is a hotspot from the ancient period to the present.In recent years,aging is mainly caused by free radicals and is closely related to the intestinal flora.Moreover,the disorder of the intestinal microecology will result in aging and diseases.Polysaccharides are one of the most abundant components in the diet and has a complex structure,which mainly decomposed and used by the microorganisms in the gastrointestinal tract.Therefore,polysaccharides are important for maintaining intestinal microflora homeostasis.Sargassum fusiforme is a nutrient-rich alga which apply to medicine and diet.The polysaccharides extracted from the Sargassum fusiforme mainly include alginate,fucoidan and brown algae starch.As for fucoidan activity has been widely studied.In recent years,studies have revealed that Sargassum fusiforme polysaccharides are a very promising natural anti-oxidant drug,but there is less research on its anti-aging activity,especially the intestinal flora.In this paper,the mechanism of the anti-aging activity of Sargassum fusiforme polysaccharides was studied by identifying its antioxidative activity,its effect on the life span of Drosophila,and the regulation of intestinal flora in aging mice.The results showed as follows: Firstly,feeding on Sargassum fusiforme polysaccharides for several days,which found that Sargassum fusiforme polysaccharides can significantly improve the survival rate and average life span of Drosophila melanogaster in the oxidative damage environment.In addition,various antioxidant-related enzyme activities have been promoted.The expression Nrf2 gene is increased and Keap1 gene is decreased.The expression of downstream antioxidant genes is upregulated such as SOD,GCLC,HO-1 and so on,but there is a gender difference,and content of MDA is decreased in Drosophila melanogaster.So Sargassum fusiforme polysaccharides increased antioxidant system functions.Secondly,through the detection of intestinal protein and genes in different groups of mice.It was found that the expression of Nrf2 and related downstream genes was significantly up-regulated in the polysaccharide group in comparison with the aging mic group,which indicate that Sargassum fusiforme polysaccharides activate Nrf2/ARE signaling pathway to restore the protective capacity of the small intestine during aging.Thirdly,sequencing and analysis of 16 S RNA of intestinal flora in different groups of mice by high-throughput sequencing.It revealed that feeding on Sargassum fusiforme polysaccharides for long-term is not only increased the diversity of intestinal microflora in aging mice,but also significantly reduced the F/B ratio of gut microbiota in aged mice.In addition,the abundance of some beneficial bacteria(such as Atopostipes,Clostridium sensu stricto,etc.)in the intestine is increased,and many harmful bacteria(such as Thaumarchaeota,Cyanobacteria phyla,etc.)are inhibited.In summary,Sargassum fusiforme polysaccharide has strong anti-oxidation activity,which not only prolongs the lifespan of Drosophila melanogaster,but also improves the composition of the intestinal microflora in aging mice.Therefore,this paper speculated that a possible mechanism for the anti-aging acticity of Sargassum fusiforme polysaccharide is to prolong life by improving the intestinal microflora structure.