A Spotlight on Archaea in Humans, Livestock and Poultry: A Review

The microbiota includes prokaryotes (archaea and bacteria) and eukaryotes. Archaea are single-celled prokaryotes and essential part of gut microbiome. Researches on archaea in ruminants and humans are more than mono-gastric. The low abundance of archaea in the gut depends on the method used (metagenomics or meta-transcriptomic) and age of people or poultry. The lack of complete recognition of archaea is due to their small number and method of identifying them (16S rRNA gene primers). The uses of archaea include analytical kit, reduce oil pollution, archaeosomes or drugs production, vaccines agents, lipid carriers in the pharmaceutical industry and molybdenum extraction in the nuclear industry. The nutritional functions of methanogenic archaea including feed utilization (ruminants) and efficiency, hydrogen reducing (human), fat deposition and enhancement of energy harvesting in mice, CAZymes genes, cecal fermentation, syntrophic potential, carotenoid source and improved transit time and appetite and SCFAs production. Archaea acting as antibiotics (produce archaeocins, sulfolobicins and halocin KPS1) and as probiotics (archaeobiotics) can reduce TMAU (trimethylaminuria) disease, cardiovascular diseases (CVDs), and atherosclerosis, brain abscess, cancer, colorectal cancer, inflammatory bowel disease (IBD), constipation, obesity, food allergies, asthma and anti-inflammation which can be prevented by using archaea, and other functions include energy homeostasis, heat shock protein (HSP) production and reducing aging.