The Anti-obesity And Gut Microbiota Amelioration Effect Of Aloe Vera Fermented Beverage

In recent years,the obesity rate has continuously increased explosively worldwide.Obesity and obesity-induced metabolic syndrome have gradually become a significant threat to public health.However,the anti-obesity products on the market always lead to undesirable side effects and drug resistance issues.Therefore,the beverages with anti-obesity function and without side effects have high research value and excellent market prospects.Aloe vera has been proven to have multiple medicinal effects including anti-inflammatory,anti-obesity,and hypoglycemic effects,and no side effects have been found in existing studies.A variety of plant fermented beverages have also been reported to have multiple biological activities such as anti-obesity,hypoglycemia,and amelioration of gut microbiota.However,the impact of Aloe vera fermented beverage（AFB）on obesity and its complications is still unclear.In this study,the crude components of AFB were measured,and the effects of AFB on anti-obesity and amelioration of gut microbiota were studied by intervening the Hep G2 cells in a high-fat environment and the mice with a high-fat diet.The main results are as follows:（1）Detection of crude components of AFB:The total polyphenols,flavonoids,sugar,reducing sugar and protein,were detected by spectrophotometry,and compared with commercial fermented beverages.The results showed that the content of total sugar,reducing sugar and active substances such as total polyphenols,flavonoids,in AFB samples were higher than those in commercial samples,while the concentration of total protein in AFB was slightly lower than those in commercial samples.（2）Effect of AFB on Hep G2 cells in a high-fat environment:When the concentrations of palmitic acid（PA）were higher than 200μmol·L^-1,Hep G2 cells cultured for 48 hours showed a significant decrease in cell viability during high fat modeling.Therefore,200μmol·L^-1 was the optimal modeling concentration for PA.When the dose of AFB exceeds 2%,there was a significant decrease in cell viability when compared to the control group,so 2%was the optimal dose for AFB.When Hep G2 cells exposed to 200μmol·L^-1 PA and 2%AFB,the cell viability significantly increased compared to the PA group without AFB,indicating that AFB alleviated the damage to Hep G2 cells in a high lipid environment.The results of Oil Red O staining showed that AFB inhibited the lipid synthesis of Hep G2 cells in a high lipid environment.（3）Effect of AFB on mice with a high-fat diet:After 6 weeks of administration,low,medium,and high doses of AFB significantly inhibited body weight gain in mice with a high-fat diet,and high doses of AFB significantly reduced liver weight and perirenal adipose weight in mice,alleviated liver fat infiltration,and significantly reduced the size of adipocytes.In addition,high doses of AFB significantly decreased the concentration of total cholesterol（TC）,alanine aminotransferase（ALT）,interleukin-10（IL-10）,in the serum of mice.The above results indicate that AFB can inhibit obesity caused by high-fat diet and metabolic syndrome caused by obesity.（4）The ameliorates effects of AFB on the gut microbiota of mice fed a high-fat diet:The Chao index,ACE index,and Shannon index of mice fed a high-fat diet increased after the administration of AFB,while the Simpson index decreased,indicating that the intervention of AFB improved the richness and diversity of the gut microbiota of mice.Principal Co-Ordinates Analysis（PCo A）,showed that AFB caused significant changes in gut microbiota of mice with a high-fat diet,and the changes were dose dependent.At the phylum level,AFB decreased the relative abundance of Firmicutes,increased the relative abundance of Bacteroidota,and significantly decreased the F/B ratio.At the genus level,AFB intervention led to the significantly increase relative abundance of norank＿f＿Muribaculaceae,Akkermansia,Oscillospiraceae,Alistipes,Rikenellaceae＿RC9＿gut＿group,and significantly decrease relative abundance of Faecalibaculum.Spearman correlation analysis showed that among the above strains,norank＿f＿Muriaculaceae,Alistipes,and Rikenellaceae＿RC9＿gut＿group had the greatest impact on mice.They had a significant negative relationship between their body weight and perirenal fat weight.There was also a significant positive correlation with the content of propionate and isobutyrate in the gut.Therefore,norank＿f＿Muribaculaceae,Rikenellaceae＿RC9＿gut＿group,and Alistipes might play important roles in the obesity inhibition process of AFB.