Flatulence is the expulsion of gas from the intestines via the anus, commonly referred to as farting. "Flatus" is the medical word for gas generated in the stomach or bowels. A proportion of intestinal gas may be swallowed environmental air, and hence flatus is not entirely generated in the stomach or bowels. The scientific study of this area of medicine is termed flatology.
Dietary fiber or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical composition, and can be grouped generally by their solubility, viscosity, and fermentability, which affect how fibers are processed in the body. Dietary fiber has two main components: soluble fiber and insoluble fiber, which are components of plant-based foods, such as legumes, whole grains and cereals, vegetables, fruits, and nuts or seeds. A diet high in regular fiber consumption is generally associated with supporting health and lowering the risk of several diseases. Dietary fiber consists of non-starch polysaccharides and other plant components such as cellulose, resistant starch, resistant dextrins, inulin, lignins, chitins, pectins, beta-glucans, and oligosaccharides.
Clostridium is a genus of anaerobic, Gram-positive bacteria. Species of Clostridium inhabit soils and the intestinal tract of animals, including humans. This genus includes several significant human pathogens, including the causative agents of botulism and tetanus. It also formerly included an important cause of diarrhea, Clostridioides difficile, which was reclassified into the Clostridioides genus in 2016.
A coccus is any bacterium or archaeon that has a spherical, ovoid, or generally round shape. Bacteria are categorized based on their shapes into three classes: cocci (spherical-shaped), bacillus (rod-shaped) and spiral. Coccus refers to the shape of the bacteria, and can contain multiple genera, such as staphylococci or streptococci. Cocci can grow in pairs, chains, or clusters, depending on their orientation and attachment during cell division. In contrast to many bacilli-shaped bacteria, most cocci bacteria do not have flagella and are non-motile.
Lactobacillus acidophilus is a rod-shaped, Gram-positive, homofermentative, anaerobic microbe first isolated from infant feces in the year 1900. The species commonly found in humans, specifically the gastrointestinal tract and oral cavity as well as various fermented foods such as fermented milk or yogurt. The species most readily grows at low pH levels, and has an optimum growth temperature of 37 °C. Certain strains of L. acidophilus show strong probiotic effects, and are commercially used in dairy production. The genome of L. acidophilus has been sequenced.
Lactiplantibacillus plantarum is a widespread member of the genus Lactiplantibacillus and commonly found in many fermented food products as well as anaerobic plant matter. L. plantarum was first isolated from saliva. Based on its ability to temporarily persist in plants, the insect intestine and in the intestinal tract of vertebrate animals, it was designated as a nomadic organism. L. plantarum is Gram positive, bacilli shaped bacterium. L. plantarum cells are rods with rounded ends, straight, generally 0.9–1.2 μm wide and 3–8 μm long, occurring singly, in pairs or in short chains. L. plantarum has one of the largest genomes known among the lactic acid bacteria and is a very flexible and versatile species. It is estimated to grow between pH 3.4 and 8.8. Lactiplantibacillus plantarum can grow in the temperature range 12 °C to 40 °C. The viable counts of the "L. plantarum" stored at refrigerated condition (4 °C) remained high, while a considerable reduction in the counts was observed stored at room temperature.
The Clostridia are a highly polyphyletic class of Bacillota, including Clostridium and other similar genera. They are distinguished from the Bacilli by lacking aerobic respiration. They are obligate anaerobes and oxygen is toxic to them. Species of the class Clostridia are often but not always Gram-positive and have the ability to form spores. Studies show they are not a monophyletic group, and their relationships are not entirely certain. Currently, most are placed in a single order called Clostridiales, but this is not a natural group and is likely to be redefined in the future.
Staphylococcus xylosus is a species of bacteria belonging to the genus Staphylococcus. It is a Gram-positive bacterium that forms clusters of cells. Like most staphylococcal species, it is coagulase-negative and exists as a commensal on the skin of humans and animals and in the environment.
Gut microbiota, gut microbiome, or gut flora are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut microbiota. The gut is the main location of the human microbiome. The gut microbiota has broad impacts, including effects on colonization, resistance to pathogens, maintaining the intestinal epithelium, metabolizing dietary and pharmaceutical compounds, controlling immune function, and even behavior through the gut–brain axis.
Peptostreptococcus is a genus of anaerobic, Gram-positive, non-spore forming bacteria. The cells are small, spherical, and can occur in short chains, in pairs or individually. They typically move using cilia. Peptostreptococcus are slow-growing bacteria with increasing resistance to antimicrobial drugs. Peptostreptococcus is a normal inhabitant of the healthy lower reproductive tract of women.
Bacteroides is a genus of Gram-negative, obligate anaerobic bacteria. Bacteroides species are non endospore-forming bacilli, and may be either motile or nonmotile, depending on the species. The DNA base composition is 40–48% GC. Unusual in bacterial organisms, Bacteroides membranes contain sphingolipids. They also contain meso-diaminopimelic acid in their peptidoglycan layer.
Bacteroides fragilis is an anaerobic, Gram-negative, pleomorphic to rod-shaped bacterium. It is part of the normal microbiota of the human colon and is generally commensal, but can cause infection if displaced into the bloodstream or surrounding tissue following surgery, disease, or trauma.
Clostridium cadaveris is an enteric, gas-forming, motile, strictly anaerobic gram-positive bacterium of the genus Clostridium. First described by Klein in 1899, it was noted to be the most prominent bacteria during human decomposition; historically it was described as "putrefying flora".
Bifidobacterium is a genus of gram-positive, nonmotile, often branched anaerobic bacteria. They are ubiquitous inhabitants of the gastrointestinal tract though strains have been isolated from the vagina and mouth of mammals, including humans. Bifidobacteria are one of the major genera of bacteria that make up the gastrointestinal tract microbiota in mammals. Some bifidobacteria are used as probiotics.
The altered Schaedler flora (ASF) is a community of eight bacterial species: two lactobacilli, one Bacteroides, one spiral bacterium of the Flexistipes genus, and four extremely oxygen sensitive (EOS) fusiform-shaped species. The bacteria are selected for their dominance and persistence in the normal microflora of mice, and for their ability to be isolated and grown in laboratory settings. Germ-free animals, mainly mice, are colonized with ASF for the purpose of studying the gastrointestinal (GI) tract. Intestinal mutualistic bacteria play an important role in affecting gene expression of the GI tract, immune responses, nutrient absorption, and pathogen resistance. The standardized microbial cocktail enabled the controlled study of microbe and host interactions, role of microbes, pathogen effects, and intestinal immunity and disease association, such as cancer, inflammatory bowel disease, diabetes, and other inflammatory or autoimmune diseases. Also, compared to germfree animals, ASF mice have fully developed immune system, resistance to opportunistic pathogens, and normal GI function and health, and are a great representation of normal mice.
Coprococcus is a genus of anaerobic cocci which are part of the human faecal microbiota. Despite the depletion of Coprococcus was found in colon cancer, there is no evidence for its protective role against colon cancer.
Finegoldia is a genus of Gram-positive bacteria. They are anaerobic cocci of the class Clostridia, with Finegoldia magna being the type species. F. magna was formerly known, along with several other Gram-positive anaerobic cocci (GPACs), as Peptostreptococcus magnus, but was moved into its own genus in 1999. The name is in honor of Sydney M. Finegold, an American microbiologist, while magna is Latin for large. It is an opportunistic human pathogen that normally colonizes skin and mucous membranes. It is often seen in biofilms on chronic ulcers such as in diabetic foot or decubitus ulcers. Most surveys have found it to be susceptible to penicillins, carbapenems and metronidazole, though resistant strains have been identified. Resistance to clindamycin is common and has been seen in over 10% of isolates in the US. One review stated that "the combination of diminished antimicrobial susceptibility, its prevalence, and the described virulence factors gives F. magna a special position among the GPAC."
Anaerococcus is a genus of bacteria. Its type species is Anaerococcus prevotii. These bacteria are Gram-positive and strictly anaerobic. The genus Anaerococcus was proposed in 2001. Its genome was sequenced in August 2009. The genus Anaerococcus is one of six genera classified within the group GPAC. These six genera are found in the human body as part of the commensal human microbiota.
Peptidiphaga gingivicola is a Gram-positive, non-spore forming, coccus shaped bacterium. Coccus are spherical and generally round in shape. Coccus are differentiated by their groupings that can range from chains, groups, or grape-like clusters. Peptidiphaga gingivicola was observed to grow in groups of 2-5 cocci between 0.2-0.9 mm in diameter. Growth was observed when cultured under anaerobic conditions between 33 and 40 degrees celsius on Blood Brucella agar for 4 days. Peptidiphaga gingivicola has been cultured from patients with periodontal disease, primarily caused by bacterial plaque formation on the gum and teeth of the oral cavity. The microbe is known to break down peptides of the gum causing tissue damage and tooth decay, leading to serious implications for oral health.
Lillian Haldeman Moore was an American microbiologist who was instrumental in founding The Anaerobe Lab at Virginia Tech. The Anaerobe Lab was built in 1970 and lab scientists led the world in developing techniques to grow and identify anaerobic bacteria in culture. She was an authority in the field of anaerobic bacteriology and food poisoning.
