Study On The Effect Of Probiotics On Seafarers’ Intestinal Microorganism

Compared with land-based workers,the risk of seafarers’ physical and mental illnesses increase during the long-distance voyages.In order to analyze the changes of seafarers’ gut microbes during voyages and explore the influence of probiotics intake on seafarers’ gut microbes,this study took 82 marine workers as the research objects and randomly divided them into two groups,including probiotics group(n = 40)and placebo group(n = 42).They were used for a 30-day long-distance voyage,and stool samples were collected at 0 day and 30 day.The metagenomic sequencing technology and specific primers combined with Pac Bio SMRT sequencing technology were utilized to deeply explore the changes in the structure of seafarers’ intestinal flora during voyages,and the influence of probiotics intake on the intestinal flora.The results of the study are as follows:1.A total of 415 strains were identified by metagenomic sequencing analysis,of which 23 strains had an average relative abundance over 1%.The PCo A analysis results showed that there were significant differences in intestinal flora’s structure at baseline and at the end of voyages in placebo group.α diversity analysis found that the placebo group’s gut microbial diversity decreases significantly at the end of voyage.Some bacteria in the placebo group changed significant in relative abundance.Bacteroides faecis and Roseburia hominis abundance significantly decreased,while Streptococcus infantis,Streptococcus gordonii and Streptococcus salivarius abundance significantly increased.After the voyage,the toluene degradation ability of the intestinal microorganisms in the placebo group of seafarers,and the ability to synthesize amino acids and glycogen decreased.The relative abundance of carbohydrate active enzyme genes in the intestinal flora were significantly reduced,of which glycoside hydrolases,glycosyltransferases and polysaccharide lyases were the most significantly reduced.The above indicates that voyages can cause disturbances of seafarers’ intestinal flora.2.The results of PCoA analysis showed that there was no significant difference in the structure of the gut microbiota of seafarers in the probiotic group at baseline and at the end of voyages.The α diversity analysis showed that the diversity of intestinal microbes in the probiotic group remained stable,but the relative content of some microbes in the probiotic group significantly changed.Bifidobacterium longum,Bifidobacterium animalis and Lactobacillus plantarum significantly increased,while Clostridium leptum,Klebsiella pneumoniae and Prevotella copri decreased significantly.The probiotic group seafarers’ gut microbial carbohydrate active enzyme gene diversity did not change significantly.In addition,we explored the correlation between the probiotics and other species with anxiety index.It is found that Klebsiella pneumoniae,Streptococcus salivarius are significantly positively correlated with anxiety index,while Bifidobacterium longum,Bifidobacterium animalis are significantly negatively correlated with anxiety index.It shows that probiotics may maintain intestinal health to a certain extent,and prevent seafarers from anxiety during long voyages.3.160 lactic acid bacteria strains and 29 Bifidobacteria strains were identified through specific primers and Pac Bio SMRT sequencing methods.After the voyage,the diversity and structure of intestinal lactic acid bacteria in the probiotic group and the placebo group remained stable,but at the end of voyage,the relative content of Streptococcus parasanguinis and Streptococcus sanguinis was significantly different between the two groups.After the voyage,there were significant differences in the structure of the intestinal Bifidobacteria in the probiotic group and the placebo group.The Bifidobacteria diversity of the probiotic group increased a lot.After the voyage,Bifidobacterium breve,Bifidobacterium longum and Bifidobacterium ruminantium in the probiotic group increased significantly.In this study were used metagenomic sequencing technology and specific primers combined with Pac Bio SMRT sequencing technology to analyze the intestinal flora of seafarers,and long-distance voyages could cause the structure imbalance and dysfunction in the intestinal flora of seafarers were found,while the intake of probiotics can maintain the stable state of the tract flora and functional metabolism.At the same time probiotics intake can alleviate the people’s anxiety state during sailing,providing a feasible method for maintaining the intestinal homeostasis and the fitness of long-distance sailors.