The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.

Uptake of substances through the lining of the INTESTINES.

The process of breakdown of food for metabolism and use by the body.

Uptake of substances through the SKIN.

The extent to which the active ingredient of a drug dosage form becomes available at the site of drug action or in a biological medium believed to reflect accessibility to a site of action.

Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.

The middle portion of the SMALL INTESTINE, between DUODENUM and ILEUM. It represents about 2/5 of the remaining portion of the small intestine below duodenum.

Analysis of the energy absorbed across a spectrum of x-ray energies/wavelengths to determine the chemical structure and electronic states of the absorbing medium.

A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.

The portion of the GASTROINTESTINAL TRACT between the PYLORUS of the STOMACH and the ILEOCECAL VALVE of the LARGE INTESTINE. It is divisible into three portions: the DUODENUM, the JEJUNUM, and the ILEUM.

The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.

The first stomach of ruminants. It lies on the left side of the body, occupying the whole of the left side of the abdomen and even stretching across the median plane of the body to the right side. It is capacious, divided into an upper and a lower sac, each of which has a blind sac at its posterior extremity. The rumen is lined by mucous membrane containing no digestive glands, but mucus-secreting glands are present in large numbers. Coarse, partially chewed food is stored and churned in the rumen until the animal finds circumstances convenient for rumination. When this occurs, little balls of food are regurgitated through the esophagus into the mouth, and are subjected to a second more thorough mastication, swallowed, and passed on into other parts of the compound stomach. (From Black's Veterinary Dictionary, 17th ed)

Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.

The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

The shortest and widest portion of the SMALL INTESTINE adjacent to the PYLORUS of the STOMACH. It is named for having the length equal to about the width of 12 fingers.

A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.

The rate dynamics in chemical or physical systems.

The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

Foodstuff used especially for domestic and laboratory animals, or livestock.

Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.

The section of the alimentary canal from the STOMACH to the ANAL CANAL. It includes the LARGE INTESTINE and SMALL INTESTINE.

Complexing agent for removal of traces of heavy metal ions. It acts also as a hypocalcemic agent.

The sum of the weight of all the atoms in a molecule.

A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.

Any of a group of polysaccharides of the general formula (C6-H10-O5)n, composed of a long-chain polymer of glucose in the form of amylose and amylopectin. It is the chief storage form of energy reserve (carbohydrates) in plants.

Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.

The giving of drugs, chemicals, or other substances by mouth.

Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.

Unstable isotopes of zinc that decay or disintegrate emitting radiation. Zn atoms with atomic weights 60-63, 65, 69, 71, and 72 are radioactive zinc isotopes.

The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.

The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.

Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.

Unstable isotopes of iron that decay or disintegrate emitting radiation. Fe atoms with atomic weights 52, 53, 55, and 59-61 are radioactive iron isotopes.

Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.

Stable zinc atoms that have the same atomic number as the element zinc, but differ in atomic weight. Zn-66-68, and 70 are stable zinc isotopes.

Regular course of eating and drinking adopted by a person or animal.

Human colonic ADENOCARCINOMA cells that are able to express differentiation features characteristic of mature intestinal cells, such as ENTEROCYTES. These cells are valuable in vitro tools for studies related to intestinal cell function and differentiation.

Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.

The remnants of plant cell walls that are resistant to digestion by the alimentary enzymes of man. It comprises various polysaccharides and lignins.

General term for a group of MALNUTRITION syndromes caused by failure of normal INTESTINAL ABSORPTION of nutrients.

A serine endopeptidase secreted by the pancreas as its zymogen, CHYMOTRYPSINOGEN and carried in the pancreatic juice to the duodenum where it is activated by TRYPSIN. It selectively cleaves aromatic amino acids on the carboxyl side.

Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.

An enzyme that catalyzes the endonucleolytic cleavage to 3'-phosphomononucleotide and 3'-phospholigonucleotide end-products. It can cause hydrolysis of double- or single-stranded DNA or RNA. (From Enzyme Nomenclature, 1992) EC 3.1.31.1.

An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.

Short-chain fatty acids of up to six carbon atoms in length. They are the major end products of microbial fermentation in the ruminant digestive tract and have also been implicated in the causation of neurological diseases in humans.

A family of sterols commonly found in plants and plant oils. Alpha-, beta-, and gamma-isomers have been characterized.

A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.

The interstitial fluid that is in the LYMPHATIC SYSTEM.

Formed from pig pepsinogen by cleavage of one peptide bond. The enzyme is a single polypeptide chain and is inhibited by methyl 2-diaazoacetamidohexanoate. It cleaves peptides preferentially at the carbonyl linkages of phenylalanine or leucine and acts as the principal digestive enzyme of gastric juice.

Properties and processes of the DIGESTIVE SYSTEM as a whole or of any of its parts.

Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.

The process of cleaving a chemical compound by the addition of a molecule of water.

Proteins obtained from foods. They are the main source of the ESSENTIAL AMINO ACIDS.

The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

Absorptive cells in the lining of the INTESTINAL MUCOSA. They are differentiated EPITHELIAL CELLS with apical MICROVILLI facing the intestinal lumen. Enterocytes are more abundant in the SMALL INTESTINE than in the LARGE INTESTINE. Their microvilli greatly increase the luminal surface area of the cell by 14- to 40 fold.

Passage of food (sometimes in the form of a test meal) through the gastrointestinal tract as measured in minutes or hours. The rate of passage through the intestine is an indicator of small bowel function.

Elements of limited time intervals, contributing to particular results or situations.

A plant species of the family POACEAE. It is a tall grass grown for its EDIBLE GRAIN, corn, used as food and animal FODDER.

Iron or iron compounds used in foods or as food. Dietary iron is important in oxygen transport and the synthesis of the iron-porphyrin proteins hemoglobin, myoglobin, cytochromes, and cytochrome oxidase. Insufficient amounts of dietary iron can lead to iron-deficiency anemia.

Calcium compounds used as food supplements or in food to supply the body with calcium. Dietary calcium is needed during growth for bone development and for maintenance of skeletal integrity later in life to prevent osteoporosis.

The parts of a macromolecule that directly participate in its specific combination with another molecule.

A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.

An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.

A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.

A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.

Inorganic or organic compounds that contain divalent iron.

Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).

Any food that has been supplemented with essential nutrients either in quantities that are greater than those present normally, or which are not present in the food normally. Fortified food includes also food to which various nutrients have been added to compensate for those removed by refinement or processing. (From Segen, Dictionary of Modern Medicine, 1992)

Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

An annual legume. The SEEDS of this plant are edible and used to produce a variety of SOY FOODS.

Steroid acids and salts. The primary bile acids are derived from cholesterol in the liver and usually conjugated with glycine or taurine. The secondary bile acids are further modified by bacteria in the intestine. They play an important role in the digestion and absorption of fat. They have also been used pharmacologically, especially in the treatment of gallstones.

Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.

A large family of narrow-leaved herbaceous grasses of the order Cyperales, subclass Commelinidae, class Liliopsida (monocotyledons). Food grains (EDIBLE GRAIN) come from members of this family. RHINITIS, ALLERGIC, SEASONAL can be induced by POLLEN of many of the grasses.

The consumption of edible substances.

A mammalian pancreatic extract composed of enzymes with protease, amylase and lipase activities. It is used as a digestant in pancreatic malfunction.

The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.

A class of organic compounds known as STEROLS or STEROIDS derived from plants.

A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.

A group of organs stretching from the MOUTH to the ANUS, serving to breakdown foods, assimilate nutrients, and eliminate waste. In humans, the digestive system includes the GASTROINTESTINAL TRACT and the accessory glands (LIVER; BILIARY TRACT; PANCREAS).

Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.

Azetidines are saturated, organic compounds containing a 4-membered ring with two carbon atoms and two nitrogen atoms (one as a secondary amine), which can be found in certain pharmaceuticals and natural substances, although they are less common than other cyclic amines.

A proteolytic enzyme obtained from Streptomyces griseus.

The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).

Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the pH of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity.

Seeds from grasses (POACEAE) which are important in the diet.

Measurement of the intensity and quality of fluorescence.

Studies comparing two or more treatments or interventions in which the subjects or patients, upon completion of the course of one treatment, are switched to another. In the case of two treatments, A and B, half the subjects are randomly allocated to receive these in the order A, B and half to receive them in the order B, A. A criticism of this design is that effects of the first treatment may carry over into the period when the second is given. (Last, A Dictionary of Epidemiology, 2d ed)

Carbohydrates present in food comprising digestible sugars and starches and indigestible cellulose and other dietary fibers. The former are the major source of energy. The sugars are in beet and cane sugar, fruits, honey, sweet corn, corn syrup, milk and milk products, etc.; the starches are in cereal grains, legumes (FABACEAE), tubers, etc. (From Claudio & Lagua, Nutrition and Diet Therapy Dictionary, 3d ed, p32, p277)

A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).

A proteolytic enzyme obtained from Carica papaya. It is also the name used for a purified mixture of papain and CHYMOPAPAIN that is used as a topical enzymatic debriding agent. EC 3.4.22.2.

A suborder of the order ARTIODACTYLA whose members have the distinguishing feature of a four-chambered stomach, including the capacious RUMEN. Horns or antlers are usually present, at least in males.

The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.

A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.

A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).

Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.

Photochemistry is the study of chemical reactions induced by absorption of light, resulting in the promotion of electrons to higher energy levels and subsequent formation of radicals or excited molecules that can undergo various reaction pathways.

That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.

A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.

The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.

A statistical means of summarizing information from a series of measurements on one individual. It is frequently used in clinical pharmacology where the AUC from serum levels can be interpreted as the total uptake of whatever has been administered. As a plot of the concentration of a drug against time, after a single dose of medicine, producing a standard shape curve, it is a means of comparing the bioavailability of the same drug made by different companies. (From Winslade, Dictionary of Clinical Research, 1992)

Any aspect of the operations in the preparation, processing, transport, storage, packaging, wrapping, exposure for sale, service, or delivery of food.

The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.

Iron-containing proteins that are widely distributed in animals, plants, and microorganisms. Their major function is to store IRON in a nontoxic bioavailable form. Each ferritin molecule consists of ferric iron in a hollow protein shell (APOFERRITINS) made of 24 subunits of various sequences depending on the species and tissue types.

Enzymes that are part of the restriction-modification systems. They catalyze the endonucleolytic cleavage of DNA sequences which lack the species-specific methylation pattern in the host cell's DNA. Cleavage yields random or specific double-stranded fragments with terminal 5'-phosphates. The function of restriction enzymes is to destroy any foreign DNA that invades the host cell. Most have been studied in bacterial systems, but a few have been found in eukaryotic organisms. They are also used as tools for the systematic dissection and mapping of chromosomes, in the determination of base sequences of DNAs, and have made it possible to splice and recombine genes from one organism into the genome of another. EC 3.21.1.

A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.

Enzymes which catalyze the hydrolases of ester bonds within DNA. EC 3.1.-.

The segment of LARGE INTESTINE between the CECUM and the RECTUM. It includes the ASCENDING COLON; the TRANSVERSE COLON; the DESCENDING COLON; and the SIGMOID COLON.

Generally refers to the digestive structures stretching from the MOUTH to ANUS, but does not include the accessory glandular organs (LIVER; BILIARY TRACT; PANCREAS).

Xylose is a monosaccharide, a type of sugar, that is commonly found in woody plants and fruits, and it is used in medical testing to assess the absorptive capacity of the small intestine.

The white liquid secreted by the mammary glands. It contains proteins, sugar, lipids, vitamins, and minerals.

Glycoside Hydrolases are a class of enzymes that catalyze the hydrolysis of glycosidic bonds, resulting in the breakdown of complex carbohydrates and oligosaccharides into simpler sugars.

Inorganic compounds derived from hydrochloric acid that contain the Cl- ion.

In ruminants, the stomach is a complex, multi-chambered organ consisting of the rumen, reticulum, omasum, and abomasum, which functions to soften and breakdown ingested plant material through microbial fermentation and mechanical churning before further digestion in the small intestine.

The evacuation of food from the stomach into the duodenum.

An indication of the contribution of a food to the nutrient content of the diet. This value depends on the quantity of a food which is digested and absorbed and the amounts of the essential nutrients (protein, fat, carbohydrate, minerals, vitamins) which it contains. This value can be affected by soil and growing conditions, handling and storage, and processing.

Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.

Nutritional physiology of animals.

An emulsifying agent produced in the LIVER and secreted into the DUODENUM. Its composition includes BILE ACIDS AND SALTS; CHOLESTEROL; and ELECTROLYTES. It aids DIGESTION of fats in the duodenum.

Fats present in food, especially in animal products such as meat, meat products, butter, ghee. They are present in lower amounts in nuts, seeds, and avocados.

(Z)-9-Octadecenoic acid 1,2,3-propanetriyl ester.

Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.

Treatment process involving the injection of fluid into an organ or tissue.

Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.

Minute projections of cell membranes which greatly increase the surface area of the cell.

Analysis of PEPTIDES that are generated from the digestion or fragmentation of a protein or mixture of PROTEINS, by ELECTROPHORESIS; CHROMATOGRAPHY; or MASS SPECTROMETRY. The resulting peptide fingerprints are analyzed for a variety of purposes including the identification of the proteins in a sample, GENETIC POLYMORPHISMS, patterns of gene expression, and patterns diagnostic for diseases.

A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.

The relationship between the dose of an administered drug and the response of the organism to the drug.

Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.

A system of organs and tissues that process and transport immune cells and LYMPH.

Surgical creation of an external opening into the ILEUM for fecal diversion or drainage. This replacement for the RECTUM is usually created in patients with severe INFLAMMATORY BOWEL DISEASES. Loop (continent) or tube (incontinent) procedures are most often employed.

Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.

A plant species of the family FABACEAE widely cultivated for ANIMAL FEED.

Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.

Hydrolases that specifically cleave the peptide bonds found in PROTEINS and PEPTIDES. Examples of sub-subclasses for this group include EXOPEPTIDASES and ENDOPEPTIDASES.

A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.

Carbonic acid calcium salt (CaCO3). An odorless, tasteless powder or crystal that occurs in nature. It is used therapeutically as a phosphate buffer in hemodialysis patients and as a calcium supplement.

The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.

The glyceryl esters of a fatty acid, or of a mixture of fatty acids. They are generally odorless, colorless, and tasteless if pure, but they may be flavored according to origin. Fats are insoluble in water, soluble in most organic solvents. They occur in animal and vegetable tissue and are generally obtained by boiling or by extraction under pressure. They are important in the diet (DIETARY FATS) as a source of energy. (Grant & Hackh's Chemical Dictionary, 5th ed)

The insertion of a tube into the stomach, intestines, or other portion of the gastrointestinal tract to allow for the passage of food products, etc.

Enzyme systems containing a single subunit and requiring only magnesium for endonucleolytic activity. The corresponding modification methylases are separate enzymes. The systems recognize specific short DNA sequences and cleave either within, or at a short specific distance from, the recognition sequence to give specific double-stranded fragments with terminal 5'-phosphates. Enzymes from different microorganisms with the same specificity are called isoschizomers. EC 3.1.21.4.

Atomic species differing in mass number but having the same atomic number. (Grant & Hackh's Chemical Dictionary, 5th ed)

A non-metal element that has the atomic symbol P, atomic number 15, and atomic weight 31. It is an essential element that takes part in a broad variety of biochemical reactions.

Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.

Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.

A polysaccharide with glucose units linked as in CELLOBIOSE. It is the chief constituent of plant fibers, cotton being the purest natural form of the substance. As a raw material, it forms the basis for many derivatives used in chromatography, ion exchange materials, explosives manufacturing, and pharmaceutical preparations.

Any substances taken in by the body that provide nourishment.

A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.

A segment of the LOWER GASTROINTESTINAL TRACT that includes the CECUM; the COLON; and the RECTUM.

The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity.

The spectrometric analysis of fluorescent X-RAYS, i.e. X-rays emitted after bombarding matter with high energy particles such as PROTONS; ELECTRONS; or higher energy X-rays. Identification of ELEMENTS by this technique is based on the specific type of X-rays that are emitted which are characteristic of the specific elements in the material being analyzed. The characteristic X-rays are distinguished and/or quantified by either wavelength dispersive or energy dispersive methods.

Enzymes that catalyze the hydrolysis of ester bonds within RNA. EC 3.1.-.

Fluids originating from the epithelial lining of the intestines, adjoining exocrine glands and from organs such as the liver, which empty into the cavity of the intestines.

The largest class of organic compounds, including STARCH; GLYCOGEN; CELLULOSE; POLYSACCHARIDES; and simple MONOSACCHARIDES. Carbohydrates are composed of carbon, hydrogen, and oxygen in a ratio of Cn(H2O)n.

The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.

The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.

An enzyme that catalyzes the hydrolysis of keratin, and of other proteins with subtilisin-like specificity. It hydrolyses peptide amides. Endopeptidase K is from the mold Tritirachium album Limber. (Enzyme Nomenclature, 1992) EC 3.4.21.64.

The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.

A series of steps taken in order to conduct research.

The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.

Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.

Unstable isotopes of carbon that decay or disintegrate emitting radiation. C atoms with atomic weights 10, 11, and 14-16 are radioactive carbon isotopes.

Colloids formed by the combination of two immiscible liquids such as oil and water. Lipid-in-water emulsions are usually liquid, like milk or lotion. Water-in-lipid emulsions tend to be creams. The formation of emulsions may be aided by amphiphatic molecules that surround one component of the system to form MICELLES.

Native, inorganic or fossilized organic substances having a definite chemical composition and formed by inorganic reactions. They may occur as individual crystals or may be disseminated in some other mineral or rock. (Grant & Hackh's Chemical Dictionary, 5th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

A mixture of related phosphoproteins occurring in milk and cheese. The group is characterized as one of the most nutritive milk proteins, containing all of the common amino acids and rich in the essential ones.

Presence of warmth or heat or a temperature notably higher than an accustomed norm.

The contents included in all or any segment of the GASTROINTESTINAL TRACT.

An organ of digestion situated in the left upper quadrant of the abdomen between the termination of the ESOPHAGUS and the beginning of the DUODENUM.

Baked food product made of flour or meal that is moistened, kneaded, and sometimes fermented. A major food since prehistoric times, it has been made in various forms using a variety of ingredients and methods.

A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.

An enzyme catalyzing the endonucleolytic cleavage of RNA at the 3'-position of a guanylate residue. EC 3.1.27.3.

Measurement and evaluation of the components of substances to be taken as FOOD.

The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.

Injections made into a vein for therapeutic or experimental purposes.

A plant genus of the family POACEAE that is the source of EDIBLE GRAIN. A hybrid with rye (SECALE CEREALE) is called TRITICALE. The seed is ground into FLOUR and used to make BREAD, and is the source of WHEAT GERM AGGLUTININS.

A disaccharide of GLUCOSE and GALACTOSE in human and cow milk. It is used in pharmacy for tablets, in medicine as a nutrient, and in industry.

A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as AMMONIUM HYDROXIDE.

Cyanogen bromide (CNBr). A compound used in molecular biology to digest some proteins and as a coupling reagent for phosphoroamidate or pyrophosphate internucleotide bonds in DNA duplexes.

The pharmacological result, either desirable or undesirable, of drugs interacting with components of the diet. (From Stedman, 25th ed)

The condition resulting from the absence or deficiency of LACTASE in the MUCOSA cells of the GASTROINTESTINAL TRACT, and the inability to break down LACTOSE in milk for ABSORPTION. Bacterial fermentation of the unabsorbed lactose leads to symptoms that range from a mild indigestion (DYSPEPSIA) to severe DIARRHEA. Lactose intolerance may be an inborn error or acquired.

Polysaccharides are complex carbohydrates consisting of long, often branched chains of repeating monosaccharide units joined together by glycosidic bonds, which serve as energy storage molecules (e.g., glycogen), structural components (e.g., cellulose), and molecular recognition sites in various biological systems.

Tritium is an isotope of hydrogen (specifically, hydrogen-3) that contains one proton and two neutrons in its nucleus, making it radioactive with a half-life of about 12.3 years, and is used in various applications including nuclear research, illumination, and dating techniques due to its low energy beta decay.

A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.

A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.

Nitric acid (HNO3). A colorless liquid that is used in the manufacture of inorganic and organic nitrates and nitro compounds for fertilizers, dye intermediates, explosives, and many different organic chemicals. Continued exposure to vapor may cause chronic bronchitis; chemical pneumonitis may occur. (From Merck Index, 11th ed)

A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.

Cholesterol present in food, especially in animal products.

The general name for a group of fat-soluble pigments found in green, yellow, and leafy vegetables, and yellow fruits. They are aliphatic hydrocarbons consisting of a polyisoprene backbone.

That portion of the electromagnetic spectrum from the UHF (ultrahigh frequency) radio waves and extending into the INFRARED RAYS frequencies.

A thermostable extracellular metalloendopeptidase containing four calcium ions. (Enzyme Nomenclature, 1992) 3.4.24.27.

A diuretic and renal diagnostic aid related to sorbitol. It has little significant energy value as it is largely eliminated from the body before any metabolism can take place. It can be used to treat oliguria associated with kidney failure or other manifestations of inadequate renal function and has been used for determination of glomerular filtration rate. Mannitol is also commonly used as a research tool in cell biological studies, usually to control osmolarity.

Proteins prepared by recombinant DNA technology.

Chromatographic techniques in which the mobile phase is a liquid.

The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.

Proteins found in any species of bacterium.

The blind sac or outpouching area of the LARGE INTESTINE that is below the entrance of the SMALL INTESTINE. It has a worm-like extension, the vermiform APPENDIX.

In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.

Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.