Study On The Immunoregulatory Effect Of Lactobacillus Helveticus Fermented Goji Berry Juice On Mice

Lycium barbarum L.has been added to the medicinal and edible resources for its medicinal value.The Ningxia goji berry is the most locally distinctive plant resource in China rich in polysaccharides,polyphenols,carotenoids and many other compounds,which are also the material basis for the goji berry’s ability to protect the liver and improve eyesight,antioxidant,anti-tumour and immune system.In contrast,the fermented supernatant of goji berry is rich in active substances that are protective of human health,providing a new direction for research into the use of fermented products in the protection against disease.In this paper,the protective effect of Lactobacillus helveticus fermented goji berry juice supernatant on cyclophosphamide-induced immunosuppressed experimental mice was investigated by fermenting the active substance goji berry with Lactobacillus helveticus fermented goji berry juice supernatant selected from laboratory kimchi,and the related effect of human intestinal bacteria 4-2-1 on the active substance Lycium barbarum polysaccharide was investigated by fermenting the active substance Lycium barbarum polysaccharide with a strain of bacteria 4-2-1 selected from the human intestinal flora.The main findings and conclusions of the study are as follows:1.Preparation of fermented goji berry juice supernatant by Lactobacillus helveticus:After pretreatment of dried goji berry,Lactobacillus helveticus was inoculated for fermentation,and the fermented goji berry juice supernatant was obtained by centrifugation.By detecting the main components in the fermented supernatant and unfermented goji berry juice,it was found that the polysaccharide content in the fermented goji berry juice supernatant increased by 25%,and the polyphenol content was 88%of the original.2.Study on the protective effect of the supernatant of goji berry juice fermented by Lactobacillus helveticus on immunosuppressive mice induced by cyclophosphamide:The experimental model of immunosuppression in BALB/c mice induced by cyclophosphamide was established,and the changes of related indexes were determined.The results showed that unfermented goji berry juice and supernatant of goji berry juice fermented by Lactobacillus helveticus could reverse the phenomena of weight loss,poor representation,reduced diet and water consumption of immunosuppressive mice induced by cyclophosphamide,improve the proliferation function of spleen lymphocytes and organ indexes(spleen,thymus,liver and gallbladder),and increase the contents of serum immunoglobulin(IgG,IgM)and blood routine related indexes,showing a good protective effect.To sum up,the supernatant of goji berry juice fermented by Lactobacillus helveticus and the unfermented goji berry juice showed the protective effect on cyclophosphamide-induced immunosuppressive mice.3.Based on MAPKs signaling pathway,the effect of supernatant of goji berry juice fermented by Lactobacillus helveticus on immunosuppression was explored.The results showed that unfermented goji beery juice and Lactobacillus helveticus fermented goji berry juice supernatant alleviated the damage to the intestinal mucosa and inflammatory infiltration,significantly increased the number of cupped cells and mucin in the intestinal,and led to an increase in the number of red marrow and white marrow in the spleen with better defined borders.In addition,unfermented goji berry juice and Lactobacillus helveticus fermented goji berry juice supernatant both increased the mRNA level of cytokines.Meanwhile,Lactobacillus helveticus fermented goji berry juice supernatant could reduce the protein content of ERK/P38 in intestinal tissue and increase the protein levels of iNOS,P38 and JNK in spleen tissue.To sum up,both unfermented goji berry juice and supernatant of goji berry juice fermented by Lactobacillus helveticus could affect immunosuppression through MAPKs signaling pathway,and the supernatant of goji berry juice fermented by Lactobacillus helveticus had a better effect.As the content of polysaccharide in fermented supernatant was higher than that in unfermented goji berry juice,it may be that Lycium barbarian polysaccharide in fermented goji berry juice supernatant enters intestinal flora to stimulate MAPKs signal pathway to regulate the immunity of mice.4.In order to investigate the role of intestinal bacteria in the absorption of Lycium barbarum polysaccharides(LBP),a strain of bacteria was isolated from human intestinal feces,and the strain was applied in the fermentation of LBP.The total number of bacteria,pH,polysaccharide content,reducing sugar content and molecular weight in the fermentation were measured and analysed to initially elucidate the digestion and absorption of LBP.The results showed that the strain was Enterobacter hormaechei through morphological and molecular biology identification,marked 4-2-1,which is a Gram-negative bacterium,and that it reached its maximum total bacterial count at 12 h.After fermentation,the pH of the medium changed from 7.98 to 7.75,the polysaccharide content changed from 682 μg/mL to 205.7μg/mL,the reducing sugar content changed from 225 μg/mL to 91.32 μg/mL,and the molecular weight changed from 8.02 to 3.44 kDa,the content of LBP decreased to about 30.2%,the content of reducing sugar decreased to about 40.6%and the molecular weight decreased to 42.9%.It indicated that the intestinal bacteria could ferment and utilize LBP,which provided a basis for further study on the interaction between LBP and intestinal bacteria.