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Pantothenic acid, also called vitamin B5, is a water-soluble vitamin required to sustain life. Pantothenic acid is needed to form coenzyme-A (CoA), and is thus critical in the metabolism and synthesis of carbohydrates, proteins, and fats. Its name is derived from the Greek pantothen meaning "from everywhere" and small quantities of pantothenic acid are found in nearly every food, with high amounts in whole grain cereals, legumes, eggs, meat, and royal jelly. Pantothenic acid is classified as a member of the secondary alcohols. Secondary alcohols are compounds containing a secondary alcohol functional group, with the general structure HOC(R)(R') (R,R'=alkyl, aryl). Pantothenic acid is considered to be soluble (in water) and acidic.

Creatinine, or creatine anhydride, is a breakdown product of creatine phosphate in muscle. The loss of a water molecule from creatine results in the formation of creatinine. Creatinine is transferred to the kidneys by blood plasma, whereupon it is eliminated from the body by glomerular filtration and partial tubular excretion. Creatinine is usually produced at a fairly constant rate by the body. Measuring serum creatinine is a simple test and it is the most commonly used indicator of renal function. A rise in blood creatinine levels is observed only with marked damage to functioning nephrons. Therefore, this test is not suitable for detecting early kidney disease. The typical reference range for women is considered about 45-90 µmol/L; for men 60-110 µmol/L. Creatine and creatinine are metabolized in the kidneys, muscle, liver, and pancreas.

Xanthurenic acid, also known as xanthurenate or 8-hydroxykynurenic acid, is a member of the class of compounds known as quinoline carboxylic acids. Quinoline carboxylic acids are quinolines in which the quinoline ring system is substituted by a carboxyl group at one or more positions. Xanthurenic acid is slightly soluble (in water). Xanthurenic acid can be found primarily in blood, feces, and urine, as well as in human epidermis tissue. Within the cell, xanthurenic acid is primarily located in the membrane. Xanthurenic acid exists in all eukaryotes, ranging from yeast to humans. In humans, xanthurenic acid is involved in the tryptophan metabolism. Moreover, xanthurenic acid is found to be associated with citrullinemia type I, which is an inborn error of metabolism. Xanthurenic acid is a metabolite from tryptophan catabolism. It is a substrate of the enzyme methyltransferases (EC 2.1.1.-) in pathway tryptophan metabolism (KEGG).

Xanthosine, also known as xanthine riboside, belongs to the class of organic compounds known as purine nucleosides. Purine nucleosides are compounds comprising a purine base attached to a ribosyl or deoxyribosyl moiety. Xanthosine is a nucleoside derived from xanthine and ribose. Xanthosine exists in all living species, ranging from bacteria to plants to humans. In plants xanthosine is the biosynthetic precursor to 7-methylxanthosine which is produced by the action of the enzyme known as 7-methylxanthosine synthase. 7-Methylxanthosine in turn is the precursor to theobromine (the active alkaloid in chocolate), which in turn is the precursor to caffeine, the active alkaloid in coffee and tea. Within humans, xanthosine participates in a number of enzymatic reactions. In particular, xanthosine can be biosynthesized from xanthylic acid; which is catalyzed by the enzyme cytosolic purine 5'-nucleotidase. In addition, xanthosine can be converted into xanthine and ribose 1-phosphate; which is mediated by the enzyme purine nucleoside phosphorylase. Xanthosine monophosphate (XMP) is an intermediate in purine metabolism, formed from IMP (inosine monophosphate).

Benzeneacetonitrile is found in garden cress. Benzeneacetonitrile is isolated from oil of garden cress (Lepidium sativum) and other plant oils.

Deoxyadenosine is a derivative of the nucleoside adenosine. It is composed of adenine attached to a deoxyribose moiety via a N9-glycosidic bond. Deoxyribose differs from ribose by the absence of oxygen in the 3' position of its ribose ring. Deoxyadenosine is a critical component of DNA. When present in sufficiently high levels, deoxyadensoine can act as an immunotoxin and a metabotoxin. An immunotoxin disrupts, limits the function, or destroys immune cells. A metabotoxin is an endogenous metabolite that causes adverse health effects at chronically high levels. Chronically high levels of deoxyadenosine are associated with adenosine deaminase (ADA) deficiency, an inborn error of metabolism. ADA deficiency damages the immune system and causes severe combined immunodeficiency (SCID). People with SCID lack virtually all immune protection from bacteria, viruses, and fungi. They are prone to repeated and persistent infections that can be very serious or life-threatening. These infections are often caused by "opportunistic" organisms that ordinarily do not cause illness in people with a normal immune system. The main symptoms of ADA deficiency are pneumonia, chronic diarrhea, and widespread skin rashes. The mechanism by which dATP functions as an immunotoxin is as follows: because deoxyadenosine is a precursor to dATP, a buildup of dATP in cells inhibits ribonucleotide reductase and prevents DNA synthesis, so cells are unable to divide. Since developing T cells and B cells are some of the most mitotically active cells, they are unable to divide and propagate to respond to immune challenges. High levels of deoxyadenosine also lead to an increase in S-adenosylhomocysteine, which is toxic to immature lymphocytes.

Cinnamic acid, also known as (Z)-cinnamate or 3-phenyl-acrylate, belongs to the class of organic compounds known as cinnamic acids. These are organic aromatic compounds containing a benzene and a carboxylic acid group forming 3-phenylprop-2-enoic acid. Cinnamic acid can be obtained from oil of cinnamon, or from balsams such as storax. Cinnamic acid is a weakly acidic compound (based on its pKa). It is a white crystalline compound that is slightly soluble in water, and freely soluble in many organic solvents. Cinnamic acid exists in all living organisms, ranging from bacteria to plants to humans. Outside of the human body, cinnamic acid has been detected, but not quantified in, chinese cinnamons. In plants, cinnamic acid is a central intermediate in the biosynthesis of myriad natural products include lignols (precursors to lignin and lignocellulose), flavonoids, isoflavonoids, coumarins, aurones, stilbenes, catechin, and phenylpropanoids.

Butyrylcarnitine, also known as (3R)-3-(butyryloxy)-4-(trimethylammonio)butanoate or L-carnitine butyryl ester, is classified as a member of the acylcarnitines. Acylcarnitines are organic compounds containing a fatty acid with the carboxylic acid attached to carnitine through an ester bond. Butyrylcarnitine is considered to be practically insoluble (in water) and acidic. Butyrylcarnitine is elevated in patients with short-chain acyl-CoA dehydrogenase (SCAD) deficiency, in infants with acute acidosis and generalized muscle weakness, and in middle-aged patients with chronic myopathy localized in muscle (OMIM: 201470).

Oxidized glutathione, also known as glutathione disulfide or GSSG, belongs to the class of organic compounds known as peptides. Peptides are compounds containing an amide derived from two or more amino carboxylic acid molecules (the same or different) by the formation of a covalent bond from the carbonyl carbon of one to the nitrogen atom of another. In humans, oxidized glutathione is involved in the metabolic disorder called leukotriene C4 synthesis deficiency pathway. Outside of the human body, oxidized glutathione has been detected, but not quantified in several different foods, such as leeks, star anises, mamey sapotes, climbing beans, and common persimmons. Oxidized glutathione is a glutathione dimer formed by a disulfide bond between the cysteine sulfhydryl side chains during the course of being oxidized. Glutathione participates in leukotriene synthesis and is a cofactor for the enzyme glutathione peroxidase. It is also important as a hydrophilic molecule that is added to lipophilic toxins and waste in the liver during biotransformation before they can become part of the bile. Glutathione is also needed for the detoxification of methylglyoxal, a toxin produced as a by-product of metabolism. This detoxification reaction is carried out by the glyoxalase system. Glyoxalase I (EC 4.4.1.5) catalyzes the conversion of methylglyoxal and reduced glutathione into S-D-lactoyl-glutathione. Glyoxalase II (EC 3.1.2.6) catalyzes the hydrolysis of S-D-lactoyl-glutathione into glutathione and D-lactate.

4,6-Dihydroxy-2-quinolinecarboxylic acid is found in fats and oils. 4,6-Dihydroxy-2-quinolinecarboxylic acid is an alkaloid from Ginkgo biloba (ginkgo).

Isovalerylalanine, also known as isopentanoylalanine, belongs to the class of organic compounds known as N-acyl-L-alpha-amino acids. These are N-acylated alpha amino acids which have the L-configuration of the alpha-carbon atom. Isovalerylalanine results from the formal condensation of the carboxy group of isovaleric acid with the amino group of L-alanine. Isovalerylalanine is one of the constituents of the organic acid profile in isovaleric acidemia, it is believed to be formed by the action of the enzyme glycine N-acylase on alanine, using isovaleryl-CoA as a substrate (PMID: 6197208). Isovaleric acidemia was the first organic acid acidemia to be documented in humans. It is an autosomal recessive inborn error in the metabolism of leucine, caused by a deficiency of the mitochondrial enzyme isovaleryl-CoA dehydrogenase (IVD) that results in the accumulation isovaleryl-CoA derivatives (PMID: 16602101). The excess of isovaleryl-CoA in plasma allows for the formation of condensation derivatives, such as isovalerylalanine which makes it one of the biomarkers for this condition.

3-Hydroxykynurenic acid is a member of quinolines. 3-Hydroxykynurenic acid is a natural product found in Aplysina cavernicola with data available.

6-Hydroxykynurenic acid is a member of quinolines. 6-Hydroxykynurenic acid is a natural product found in Ephedra pachyclada, Ephedra regeliana, and other organisms with data available.

The 7,8-dihydro-7,8-dihydroxy derivative of kynurenic acid." []

Glycyl-Isoleucine is a dipeptide composed of glycine and isoleucine. It is an incomplete breakdown product of protein digestion or protein catabolism. Some dipeptides are known to have physiological or cell-signaling effects although most are simply short-lived intermediates on their way to specific amino acid degradation pathways following further proteolysis. This dipeptide has not yet been identified in human tissues or biofluids and so it is classified as an 'Expected' metabolite.

N-methyltyramine (NMT) is a phenolic amine. NMT is a potent stimulant of gastrin release present in alcoholic beverages produced by alcoholic fermentation, but not by distillation (i.e.: beer.). NMT is well absorbed in the small intestine, especially in the duodenum and jejunum. NMT is metabolized in the liver (the site of first-pass metabolism), but not in the small-intestinal mucosa. NMT is occasionally present in the stools of children and infants. Satisfactory results have been obtained in treating infective shock with injection of natural Fructus Aurantii immaturus (nat-FAI); the anti-shock effective compositions in FAI have been proved to be synephrine and NMT. (PMID: 10772638, 2570680).

Isobutyryl-L-carnitine

Cinnamic acid is a monocarboxylic acid that consists of acrylic acid bearing a phenyl substituent at the 3-position. It is found in Cinnamomum cassia. It has a role as a plant metabolite. It is a member of styrenes and a member of cinnamic acids. It is a conjugate acid of a cinnamate. trans-Cinnamic acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Cinnamic acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Cinnamic acid is a natural product found in Ipomoea leptophylla, Camellia sinensis, and other organisms with data available. Cinnamic acid has the formula C6H5CHCHCOOH and is an odorless white crystalline acid, which is slightly soluble in water. It has a melting point of 133 degree centigrade and a boiling point of 300 degree centigrade. Cinnamic acid is a metabolite found in or produced by Saccharomyces cerevisiae. See also: Cinnamon (part of); Chinese Cinnamon (part of); Stevia rebaudiuna Leaf (part of) ... View More ...

A hydroxy-1,4-naphthoquinone that is 1,4-naphthoquinone substituted by hydroxy and 3-methylbut-2-en-1-yl groups at positions 2 and 3, respectively. It is a natural compound that exhibits antibacterial and anticancer properties, first isolated in 1882 from the bark of Tabebuia avellanedae." []

A benzochromenone that is 3,4-dihydro-2H-benzo[h]chromene-5,6-dione substituted by geminal methyl groups at position 2. Isolated from Tabebuia avellanedae, it exhibits antineoplastic and anti-inflammatory activities." []

3-methoxy-4',5-dihydroxy-trans-stilbene is a stilbenoid that is trans-resveratrol in which one of the meta-hydroxy groups is converted to the corresponding methyl ether. It is functionally related to a trans-resveratrol. 3-Methoxy-4',5-dihydroxy-trans-stilbene is a natural product found in Soymida febrifuga, Streptomyces avermitilis, and other organisms with data available.

5-[2-(4-methoxyphenyl)ethenyl]benzene-1,3-diol is a stilbenoid. (E)-5-(4-Methoxystyryl)benzene-1,3-diol has been reported in Alpinia hainanensis, Dracaena cochinchinensis, and other organisms with data available.

N-Acetyl-L-valine or N-Acetylvaline, belongs to the class of organic compounds known as N-acyl-alpha amino acids. N-acyl-alpha amino acids are compounds containing an alpha amino acid which bears an acyl group at its terminal nitrogen atom. N-Acetylvaline can also be classified as an alpha amino acid or a derivatized alpha amino acid. Technically, N-Acetylvaline is a biologically available N-terminal capped form of the proteinogenic alpha amino acid L-valine. N-acetyl amino acids can be produced either via direct synthesis of specific N-acetyltransferases or via the proteolytic degradation of N-acetylated proteins by specific hydrolases. N-terminal acetylation of proteins is a widespread and highly conserved process in eukaryotes that is involved in protection and stability of proteins (PMID: 16465618). About 85% of all human proteins and 68% of all yeast proteins are acetylated at their N-terminus (PMID: 21750686). Several proteins from prokaryotes and archaea are also modified by N-terminal acetylation. The majority of eukaryotic N-terminal-acetylation reactions occur through N-acetyltransferase enzymes or NAT’s (PMID: 30054468). These enzymes consist of three main oligomeric complexes NatA, NatB, and NatC, which are composed of at least a unique catalytic subunit and one unique ribosomal anchor. The substrate specificities of different NAT enzymes are mainly determined by the identities of the first two N-terminal residues of the target protein. The human NatA complex co-translationally acetylates N-termini that bear a small amino acid (A, S, T, C, and occasionally V and G) (PMID: 30054468). NatA also exists in a monomeric state and can post-translationally acetylate acidic N-termini residues (D-, E-). NatB and NatC acetylate N-terminal methionine with further specificity determined by the identity of the second amino acid. N-acetylated amino acids, such as N-acetylvaline can be released by an N-acylpeptide hydrolase from peptides generated by proteolytic degradation (PMID: 16465618). In addition to the NAT enzymes and protein-based acetylation, N-acetylation of free valine can also occur. Excessive amounts N-acetyl amino acids including N-acetylvaline(as well as N-acetylglycine, N-acetylserine, N-acetylmethionine, N-acetylglutamate, N-acetylalanine, N-acetylleucine and smaller amounts of N-acetylglutamine, N-acetylisoleucine, and N-acetylthreonine) can be detected in the urine with individuals with acylase I deficiency, a genetic disorder (PMID: 16465618). Aminoacylase I is a soluble homodimeric zinc binding enzyme that catalyzes the formation of free aliphatic amino acids from N-acetylated precursors. In humans, Aminoacylase I is encoded by the aminoacylase 1 gene (ACY1) on chromosome 3p21 that consists of 15 exons (OMIM 609924). Individuals with aminoacylase I deficiency will experience convulsions, hearing loss and difficulty feeding (PMID: 16465618). ACY1 can also catalyze the reverse reaction, the synthesis of acetylated amino acids. Many N-acetylamino acids, including N-acetylthreonine, are classified as uremic toxins if present in high abundance in the serum or plasma (PMID: 26317986; PMID: 20613759). Uremic toxins are a diverse group of endogenously produced molecules that, if not properly cleared or eliminated by the kidneys, can cause kidney damage, cardiovascular disease and neurological deficits (PMID: 18287557).

Threonylisoleucine is a dipeptide composed of threonine and isoleucine. It is an incomplete breakdown product of protein digestion or protein catabolism. Dipeptides are organic compounds containing a sequence of exactly two alpha-amino acids joined by a peptide bond. Some dipeptides are known to have physiological or cell-signalling effects although most are simply short-lived intermediates on their way to specific amino acid degradation pathways following further proteolysis.

3,4-Dihydro-2H-1-benzopyran-2-one, also known as 3,4-dihydrocoumarin or 1,2-benzodihydropyrone, belongs to the class of organic compounds known as 3,4-dihydrocoumarins. These are 3,4-dihydrogenated coumarins. Coumarin is a bicyclic compound that are 1-benzopyran carrying an oxo group at the 2-position. 3,4-Dihydro-2H-1-benzopyran-2-one exists in all living organisms, ranging from bacteria to humans. 3,4-Dihydro-2H-1-benzopyran-2-one is a sweet, almond, and cinnamon tasting compound. 3,4-Dihydro-2H-1-benzopyran-2-one has been detected, but not quantified, in several different foods, such as green vegetables, pulses, sour cherries, and tarragons. A chromanone that is the 3,4-dihydro derivative of coumarin.

Zeanic acid is found in cereals and cereal products. Zeanic acid is isolated from corn steep liquor.