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L-Theanine, also known as L-gamma-glutamylethylamide or N-gamma-ethyl-L-glutamine, is a member of the class of compounds known as glutamine and derivatives. These compounds contain glutamine or a derivative thereof resulting from a reaction of glutamine at the amino group or the carboxy group, or from the replacement of any hydrogen of glycine by a heteroatom. L-Theanine is slightly soluble (in water) and a moderately acidic compound (based on its pKa). L-Theanine can be found in saliva. The regulatory status of theanine varies by country. In Japan, L-theanine has been approved for use in all foods, including herb teas, soft drinks, and desserts. Restrictions apply to infant foods. In the United States, the Food and Drug Administration (FDA) considers it to be generally recognized as safe (GRAS) and allows its sale as a dietary supplement. The German Federal Institute for Risk Assessment, an agency of their Federal Ministry of Food and Agriculture, objects to the addition of L-theanine to beverages. The European Food Safety Authority EFSA advised negatively on health claims related to L-theanine and cognitive function, alleviation of psychological stress, maintenance of normal sleep, and reduction of menstrual discomfort. Therefore, health claims for L-theanine are prohibited in the European Union (Wikipedia). L-Theanine is found in mushrooms and is a constituent of tea (Thea sinensis) and of the fungus Imleria badia. L-Theanine has been shown to exhibit neuroprotectant and neuroprotective functions (PMID: 20416364, 20416364).

Itaconic acid is a dicarboxylic acid that is methacrylic acid in which one of the methyl hydrogens is substituted by a carboxylic acid group. It has a role as a fungal metabolite and a human metabolite. It is a dicarboxylic acid and an olefinic compound. It derives from a succinic acid. It is a conjugate acid of an itaconate(2-). This dicarboxylic acid is a white solid that is soluble in water, ethanol, and acetone. Historically, itaconic acid was obtained by the distillation of citric acid, but currently it is produced by fermentation. The name itaconic acid was devised as an anagram of aconitic acid, another derivative of citric acid. Itaconic acid, also known as itaconate, belongs to the class of organic compounds known as branched fatty acids. These are fatty acids containing a branched chain. Itaconic acid is a very hydrophobic molecule, practically insoluble in water, and relatively neutral. Since the 1960s, it is produced industrially by the fermentation of carbohydrates such as glucose or molasses using fungi such as Aspergillus itaconicus or Aspergillus terreus. For A. terreus the itaconate pathway is mostly elucidated. The generally accepted route for itaconate is via glycolysis, tricarboxylic acid cycle, and a decarboxylation of cis-aconitate to itaconate via cis-aconitate-decarboxylase. The smut fungus Ustilago maydis uses an alternative route. Cis-aconitate is converted to the thermodynamically favoured trans-aconitate via aconitate-Δ-isomerase (Adi1). trans-Aconitate is further decarboxylated to itaconate by trans-aconitate-decarboxylase (Tad1). Itaconic acid is also produced in cells of macrophage lineage. It was shown that itaconate is a covalent inhibitor of the enzyme isocitrate lyase in vitro. As such, itaconate may possess antibacterial activities against bacteria expressing isocitrate lyase (such as Salmonella enterica and Mycobacterium tuberculosis). It is also sythesized in the laboratory, where dry distillation of citric acid affords itaconic anhydride, which undergoes hydrolysis to itaconic acid.

Benzocaine is a surface anesthetic that acts by preventing transmission of impulses along nerve fibers and at nerve endings. Benzocaine is a local anesthetic commonly used as a topical pain reliever. It is the active ingredient in many over-the-counter analgesic ointments. Benzocaine is an ester, a compound made from the organic acid PABA (para-aminobenzoic acid) and ethanol. The process in which this ester is created is known as Fischer esterification.

2-Amino-3-methylbutanoic acid

The D-enantiomer of phenylalanine." []

Racemethionine, also known as DL-methionine or hmet, belongs to the class of organic compounds known as methionine and derivatives. Methionine and derivatives are compounds containing methionine or a derivative thereof resulting from reaction of methionine at the amino group or the carboxy group, or from the replacement of any hydrogen of glycine by a heteroatom. Methionine is an alpha-amino acid with the chemical formula HO2CCH(NH2)CH2CH2SCH3. This essential amino acid is classified as nonpolar. Racemethionine exists in all living organisms, ranging from bacteria to humans. Racemethionine is a mild, acidic, and sulfurous tasting compound. Racemethionine is found, on average, in the highest concentration within a few different foods, such as wheats, oats, and ryes and in a lower concentration in spinachs, white cabbages, and green zucchinis. Racemethionine is used as a flavouring ingredient and dietary supplement.

Caffeine is a methyl xanthine alkaloid that is also classified as a purine. Formally, caffeine belongs to the class of organic compounds known as xanthines. These are purine derivatives with a ketone group conjugated at carbons 2 and 6 of the purine moiety. Caffeine is chemically related to the adenine and guanine bases of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It is found in the seeds, nuts, or leaves of a number of plants native to Africa, East Asia and South America and helps to protect them against predator insects and to prevent germination of nearby seeds. The most well-known source of caffeine is the coffee bean. Caffeine is the most widely consumed psychostimulant drug in the world. 85% of American adults consumed some form of caffeine daily, consuming 164 mg on average. Caffeine is mostly is consumed in the form of coffee. Caffeine is a central nervous system stimulant that reduces fatigue and drowsiness. At normal doses, caffeine has variable effects on learning and memory, but it generally improves reaction time, wakefulness, concentration, and motor coordination. Caffeine is a proven ergogenic aid in humans. Caffeine improves athletic performance in aerobic (especially endurance sports) and anaerobic conditions. Moderate doses of caffeine (around 5 mg/kg) can improve sprint performance, cycling and running time trial performance, endurance and cycling power output (PMID: 32551869). At intake levels associated with coffee consumption, caffeine appears to exert most of its biological effects through the antagonism of the A1 and A2A subtypes of the adenosine receptor. Adenosine is an endogenous neuromodulator with mostly inhibitory effects, and adenosine antagonism by caffeine results in effects that are generally stimulatory. Some physiological effects associated with caffeine administration include central nervous system stimulation, acute elevation of blood pressure, increased metabolic rate, and diuresis. A number of in vitro and in vivo studies have demonstrated that caffeine modulates both innate and adaptive immune responses. For instance, studies indicate that caffeine and its major metabolite paraxanthine suppress neutrophil and monocyte chemotaxis, and also suppress production of the pro-inflammatory cytokine tumor necrosis factor (TNF) alpha from human blood. Caffeine has also been reported to suppress human lymphocyte function as indicated by reduced T-cell proliferation and impaired production of Th1 (interleukin [IL]-2 and interferon [IFN]-gamma), Th2 (IL-4, IL-5) and Th3 (IL-10) cytokines. Studies also indicate that caffeine suppresses antibody production. The evidence suggests that at least some of the immunomodulatory actions of caffeine are mediated via inhibition of cyclic adenosine monophosphate (cAMP)-phosphodiesterase (PDE), and consequential increase in intracellular cAMP concentrations. Overall, these studies indicate that caffeine, like other members of the methylxanthine family, is largely anti-inflammatory in nature, and based on the pharmacokinetics of caffeine, many of its immunomodulatory effects occur at concentrations that are relevant to normal human consumption. (PMID: 16540173). Caffeine is rapidly and almost completely absorbed in the stomach and small intestine and distributed to all tissues, including the brain. Caffeine metabolism occurs primarily in the liver, where the activity of the cytochrome P450 isoform CYP1A2 accounts for almost 95% of the primary metabolism of caffeine. CYP1A2-catalyzed 3-demethylation of caffeine results in the formation of 1,7-dimethylxanthine (paraxanthine). Paraxanthine may be demethylated by CYP1A2 to form 1-methylxanthine, which may be oxidized to 1-methyluric acid by xanthine oxidase. Paraxanthine may also be hydroxylated by CYP2A6 to form 1,7-dimethyluric acid, or acetylated by N-acetyltransferase 2 (NAT2) to form 5-acetylamino-6-formylamino-3-methyluracil, an unstable compound that may be deformylated nonenzymatically to form 5-acetylamino-6-amino-3-methyluracil. Caffeine concentrations in coffee beverages can be quite variable. A standard cup of coffee is often assumed to provide 100 mg of caffeine, but a recent analysis of 14 different specialty coffees purchased at coffee shops in the US found that the amount of caffeine in 8 oz (=240 ml) of brewed coffee ranged from 72 to 130 mg. Caffeine in espresso coffees ranged from 58 to 76 mg in a single shot. (PMID: 16507475).

Valine (Val) or L-valine is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. L-valine is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Valine is found in all organisms ranging from bacteria to plants to animals. It is classified as a non-polar, uncharged (at physiological pH) aliphatic amino acid. Valine was first isolated from casein in 1901 by Hermann Emil Fischer. The name valine comes from valeric acid, which in turn is named after the plant valerian due to the presence of valine in the roots of the plant. Valine is essential in humans, meaning the body cannot synthesize it, and it must be obtained from the diet. Human dietary sources are foods that contain protein, such as meats, dairy products, soy products, beans and legumes. L-valine is a branched chain amino acid (BCAA). The BCAAs consist of leucine, valine and isoleucine (and occasionally threonine). BCAAs are essential amino acids whose carbon structure is marked by a branch point at the beta-carbon position. BCAAs are critical to human life and are particularly involved in stress, energy and muscle metabolism. BCAA supplementation as therapy, both oral and intravenous, in human health and disease holds great promise. BCAAs have different metabolic routes, with valine going solely to carbohydrates (glucogenic), leucine solely to fats (ketogenic) and isoleucine being both a glucogenic and a ketogenic amino acid. The different metabolism accounts for different requirements for these essential amino acids in humans: 12 mg/kg, 14 mg/kg and 16 mg/kg of valine, leucine and isoleucine respectively. Like other branched-chain amino acids, the catabolism of valine starts with the removal of the amino group by transamination, giving alpha-ketoisovalerate, an alpha-keto acid, which is converted to isobutyryl-CoA through oxidative decarboxylation by the branched-chain α-ketoacid dehydrogenase complex. This is further oxidised and rearranged to succinyl-CoA, which can enter the citric acid cycle. Furthermore, these amino acids have different deficiency symptoms. Valine deficiency is marked by neurological defects in the brain, while isoleucine deficiency is marked by muscle tremors. Many types of inborn errors of BCAA metabolism exist, and are marked by various abnormalities. The most common form is the maple syrup urine disease, marked by a characteristic urinary odor. Other abnormalities are associated with a wide range of symptoms, such as mental retardation, ataxia, hypoglycemia, spinal muscle atrophy, rash, vomiting and excessive muscle movement. Most forms of BCAA metabolism errors are corrected by dietary restriction of BCAA and at least one form is correctable by supplementation with 10 mg of biotin daily. BCAA are decreased in patients with liver disease, such as hepatitis, hepatic coma, cirrhosis, extrahepatic biliary atresia or portacaval shunt. Valine in particular, has been established as a useful supplemental therapy to the ailing liver. Valine, like other branched-chain amino acids, is associated with insulin resistance: higher levels of valine are observed in the blood of diabetic mice, rats, and humans (PMID: 25287287). Mice fed a valine deprivation diet for one day have improved insulin sensitivity and feeding of a valine deprivation diet for one week significantly decreases blood glucose levels (PMID: 24684822). In diet-induced obese and insulin resistant mice, a diet with decreased levels of valine and the other branched-chain amino acids results in reduced adiposity and improved insulin sensitivity (PMID: 29266268). In sickle-cell disease, valine substitutes for the hydrophilic amino acid glutamic acid in hemoglobin. Because valine is hydrophobic, the hemoglobin does not fold correctly. Hypervalinemia is another example of an inborn error of metabolism involving valine.

Allopurinol is only found in individuals that have used or taken this drug. It is a xanthine oxidase inhibitor that decreases uric acid production. It also acts as an antimetabolite on some simpler organisms. [PubChem]Allopurinol and its active metabolite, oxypurinol, inhibits the enzyme xanthine oxidase, blocking the conversion of the oxypurines hypoxanthine and xanthine to uric acid. Elevated concentrations of oxypurine and oxypurine inhibition of xanthine oxidase through negative feedback results in a decrease in the concentrations of uric acid in the serum and urine. Allopurinol also facilitates the incorporation of hypoxanthine and xanthine into DNA and RNA, leading to a feedback inhibition of de novo purin synthesis and a decrease in serum uric acid concentrations as a result of an increase in nucleotide concentration.

A benzoate ester that is the ethyl ester of 3-aminobenzoic acid. Used (in the form of its methanesulfonate salt) as an anaesthetic for fish." []

Achromycin is a natural product found in Allium sativum with data available. A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.

An alpha-amino acid that is pyrrolidine bearing a carboxy substituent at position 2." []

Mesaconic acid, also known as 2-methylfumarate or citronic acid, belongs to the class of organic compounds known as methyl-branched fatty acids. These are fatty acids with an acyl chain that has a methyl branch. Usually, they are saturated and contain only one or more methyl group. However, branches other than methyl may be present. Mesaconic acid is a dicarboxylic butenoic acid, with a methyl group in position 2 and the double bound between carbons 2 and 3. Mesaconic acid was first studied for its physical properties in 1874 by Jacobus van ‘t Hoff (https://web.archive.org/web/20051117102410/http://dbhs.wvusd.k12.ca.us/webdocs/Chem-History/Van%27t-Hoff-1874.html). It is now known to be involved in the biosynthesis of vitamin B12 and it is also a competitor inhibitor of the reduction of fumarate.

Aconitic acid is a tricarboxylic acid that is prop-1-ene substituted by carboxy groups at positions 1, 2 and 3. It is a conjugate acid of an aconitate(3-). Aconitic acid is a natural product found in Glycine max, Zea mays, and other organisms with data available. A tricarboxylic acid with the formula (COOH)-CH2-C(COOH)=CH-COOH.

Linoleic acid is a doubly unsaturated fatty acid, also known as an omega-6 fatty acid, occurring widely in plant glycosides. In this particular polyunsaturated fatty acid (PUFA), the first double bond is located between the sixth and seventh carbon atom from the methyl end of the fatty acid (n-6). Linoleic acid is an essential fatty acid in human nutrition because it cannot be synthesized by humans. It is used in the biosynthesis of prostaglandins (via arachidonic acid) and cell membranes (From Stedman, 26th ed). Linoleic acid is found to be associated with isovaleric acidemia, which is an inborn error of metabolism.

An alpha-amino acid that is phenylalanine bearing a hydroxy substituent at position 4 on the phenyl ring." []

Piperidine (Azinane after the Hantzsch Widman nomenclature) is an organic compound with the molecular formula (CH2)5NH. This heterocyclic amine consists of a six-membered ring containing five methylene units and one nitrogen atom. It is a colorless fuming liquid with an odor described as ammoniacal, pepper-like; the name comes from the genus name Piper, which is the Latin word for pepper. Piperidine is found in barley, black pepper (Piper nigrum). Piperidine has been found to be a microbial metabolite. Piperidine is a flavouring agent and it is also widely used as a building block and chemical reagent in the synthesis of organic compounds, including pharmaceuticals. Piperidine is a widely used secondary amine. It is used to convert ketones to enamines. Enamines derived from piperidine can be used in the Stork enamine alkylation reaction. Piperidine is used as a solvent and as a base. The same is true for certain derivatives: N-formylpiperidine is a polar aprotic solvent with better hydrocarbon solubility than other amide solvents, and 2,2,6,6-tetramethylpiperidine is highly sterically hindered base, useful because of its low nucleophilicity and high solubility in organic solvents.

Pyroglutamic acid (5-oxoproline) is a cyclized derivative of L-glutamic acid. It is an uncommon amino acid derivative in which the free amino group of glutamic acid cyclizes to form a lactam. It is formed nonenzymatically from glutamate, glutamine, and gamma-glutamylated peptides, but it can also be produced by the action of gamma-glutamylcyclotransferase on an L-amino acid. Elevated blood levels may be associated with problems of glutamine or glutathione metabolism. This compound is found in substantial amounts in brain tissue and other tissues in bound form, especially skin. It is also present in plant tissues. It is sold, over the counter, as a "smart drug" for improving blood circulation in the brain. Pyroglutamate in the urine is a biomarker for the consumption of cheese. When present in sufficiently high levels, pyroglutamic acid can act as an acidogen and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of pyroglutamic acid are associated with at least five inborn errors of metabolism including 5-oxoprolinuria, 5-oxoprolinase deficiency, glutathione synthetase deficiency, hawkinsinuria, and propionic acidemia. Pyroglutamic acid is an organic acid. Abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of the untreated IEMs mentioned above. Many affected children with organic acidemias experience intellectual disability or delayed development. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. It has been shown that pyroglutamic acid releases GABA from the cerebral cortex and displays anti-anxiety effects in a simple approach-avoidance conflict situation in the rat. In clinical pharmacology experiments, pyroglutamic acid significantly shortens the plasma half-life of ethanol during acute intoxication.

Tyrosine (Tyr) or L-tyrosine is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. L-tyrosine is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Tyrosine is found in all organisms ranging from bacteria to plants to animals. It is classified as a non-polar, uncharged (at physiological pH) aromatic amino acid. Tyrosine is a non-essential amino acid, meaning the body can synthesize it – usually from phenylalanine. The conversion of phenylalanine to tyrosine is catalyzed by the enzyme phenylalanine hydroxylase, a monooxygenase. This enzyme catalyzes the reaction causing the addition of a hydroxyl group to the end of the 6-carbon aromatic ring of phenylalanine, such that it becomes tyrosine. Tyrosine is found in many high-protein food products such as chicken, turkey, fish, milk, yogurt, cottage cheese, cheese, peanuts, almonds, pumpkin seeds, sesame seeds, soy products, lima beans, avocados and bananas. Tyrosine is one of the few amino acids that readily passes the blood-brain barrier. Once in the brain, it is a precursor for the neurotransmitters dopamine, norepinephrine and epinephrine, better known as adrenalin. These neurotransmitters are an important part of the body's sympathetic nervous system, and their concentrations in the body and brain are directly dependent upon dietary tyrosine. Tyrosine is not found in large concentrations throughout the body, probably because it is rapidly metabolized. Folic acid, copper and vitamin C are cofactor nutrients of these reactions. Tyrosine is also the precursor for hormones, including thyroid hormones (diiodotyrosine), catecholestrogens and the major human pigment, melanin. Tyrosine is an important amino acid in many proteins, peptides and even enkephalins, the body's natural pain reliever. Valine and other branched amino acids, and possibly tryptophan and phenylalanine may reduce tyrosine absorption. A number of genetic errors of tyrosine metabolism have been identified, such as hawkinsinuria and tyrosinemia I. The most common feature of these diseases is the increased amount of tyrosine in the blood, which is marked by decreased motor activity, lethargy and poor feeding. Infection and intellectual deficits may occur. Vitamin C supplements can help reverse these disease symptoms. Some adults also develop elevated tyrosine in their blood. This typically indicates a need for more vitamin C. More tyrosine is needed under stress, and tyrosine supplements prevent the stress-induced depletion of norepinephrine and can help aleviate biochemical depression. However, tyrosine may not be good for treating psychosis. Many antipsychotic medications apparently function by inhibiting tyrosine metabolism. L-Dopa, which is directly used in Parkinson's, is made from tyrosine. Tyrosine, the nutrient, can be used as an adjunct in the treatment of Parkinson's. Peripheral metabolism of tyrosine necessitates large doses of tyrosine, however, compared to L-Dopa (http://www.dcnutrition.com). In addition to its role as a precursor for neurotransmitters, tyrosine plays an important role for the function of many proteins. Within many proteins or enzymes, certain tyrosine residues can be tagged (at the hydroxyl group) with a phosphate group (phosphorylated) by specialized protein kinases. In its phosphorylated form, tyrosine is called phosphotyrosine. Tyrosine phosphorylation is considered to be one of the key steps in signal transduction and regulation of enzymatic activity. Tyrosine (or its precursor phenylalanine) is also needed to synthesize the benzoquinone structure which forms part of coenzyme Q10.

Deoxycholic acid is a secondary bile acid produced in the liver and is usually conjugated with glycine or taurine. It facilitates fat absorption and cholesterol excretion. Bile acids are steroid acids found predominantly in the bile of mammals. The distinction between different bile acids is minute, and depends only on the presence or absence of hydroxyl groups on positions 3, 7, and 12. Bile acids are physiological detergents that facilitate excretion, absorption, and transport of fats and sterols in the intestine and liver. Bile acids are also steroidal amphipathic molecules derived from the catabolism of cholesterol. They modulate bile flow and lipid secretion, are essential for the absorption of dietary fats and vitamins, and have been implicated in the regulation of all the key enzymes involved in cholesterol homeostasis. Bile acids recirculate through the liver, bile ducts, small intestine, and portal vein to form an enterohepatic circuit. They exist as anions at physiological pH, and consequently require a carrier for transport across the membranes of the enterohepatic tissues. The unique detergent properties of bile acids are essential for the digestion and intestinal absorption of hydrophobic nutrients. Bile acids have potent toxic properties (e.g. membrane disruption) and there are a plethora of mechanisms to limit their accumulation in blood and tissues (PMID: 11316487, 16037564, 12576301, 11907135). When present in sufficiently high levels, deoxycholic acid can act as a hepatotoxin, a metabotoxin, and an oncometabolite. A hepatotoxin causes damage to the liver or liver cells. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. An oncometabolite is a compound, when present at chronically high levels, that promotes tumour growth and survival. Among the primary bile acids, cholic acid is considered to be the least hepatotoxic while deoxycholic acid is the most hepatoxic (PMID: 1641875). The liver toxicity of bile acids appears to be due to their ability to peroxidate lipids and to lyse liver cells. High bile acid levels lead to the generation of reactive oxygen species and reactive nitrogen species, disruption of the cell membrane and mitochondria, induction of DNA damage, mutation and apoptosis, and the development of reduced apoptosis capability upon chronic exposure (PMID: 24884764). Chronically high levels of deoxycholic acid are associated with familial hypercholanemia. In hypercholanemia, bile acids, including deoxycholic acid, are elevated in the blood. This disease causes liver damage, extensive itching, poor fat absorption, and can lead to rickets due to lack of calcium in bones. The deficiency of normal bile acids in the intestines results in a deficiency of vitamin K, which also adversely affects clotting of the blood. The bile acid ursodiol (ursodeoxycholic acid) can improve symptoms associated with familial hypercholanemia. Chronically high levels of deoxycholic acid are also associated with several forms of cancer including colon cancer, pancreatic cancer, esophageal cancer, and many other GI cancers.

Epicatechin is an antioxidant flavonoid, occurring especially in woody plants as both (+)-catechin and (-)-epicatechin (cis) forms. Catechin is a tannin peculiar to green and white tea because the black tea oxidation process reduces catechins in black tea. Catechin is a powerful, water soluble polyphenol and antioxidant that is easily oxidized. Several thousand types are available in the plant world. As many as two thousand are known to have a flavon structure and are called flavonoids. Catechin is one of them. Green tea is manufactured from fresh, unfermented tea leaves; the oxidation of catechins is minimal, and hence they are able to serve as antioxidants. Researchers believe that catechin is effective because it easily sticks to proteins, blocking bacteria from adhering to cell walls and disrupting their ability to destroy them. Viruses have hooks on their surfaces and can attach to cell walls. The catechin in green tea prevents viruses from adhering and causing harm. Catechin reacts with toxins created by harmful bacteria (many of which belong to the protein family) and harmful metals such as lead, mercury, chrome, and cadmium. From its NMR espectra, there is a doubt on 2 and 3 atoms configuration. It seems to be that they are in trans position.

Proline (Pro), also known as L-proline is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. Proline is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Proline is found in all organisms ranging from bacteria to plants to animals. It is classified as an aliphatic, non-polar amino acid. Proline is sometimes called an imino acid, although the IUPAC definition of an imine requires a carbon-nitrogen double bond. Proline is a non-essential amino acid that is synthesized from glutamic acid. It is an essential component of collagen and is important for proper functioning of joints and tendons. Proline is derived from the amino acid L-glutamate in which glutamate-5-semialdehyde is first formed by glutamate 5-kinase and glutamate-5-semialdehyde dehydrogenase (which requires NADH or NADPH). This semialdehyde can then either spontaneously cyclize to form 1-pyrroline-5-carboxylic acid, which is reduced to proline by pyrroline-5-carboxylate reductase, or turned into ornithine by ornithine aminotransferase, followed by cyclization by ornithine cyclodeaminase to form proline. L-Proline has been found to act as a weak agonist of the glycine receptor and of both NMDA and non-NMDA ionotropic glutamate receptors. It has been proposed to be a potential endogenous excitotoxin/neurotoxin. Studies in rats have shown that when injected into the brain, proline non-selectively destroys pyramidal and granule cells (PMID: 3409032 ). Therefore, under certain conditions proline can act as a neurotoxin and a metabotoxin. A neurotoxin causes damage to nerve cells and nerve tissues. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of proline are associated with at least five inborn errors of metabolism, including hyperprolinemia type I, hyperprolinemia type II, iminoglycinuria, prolinemia type II, and pyruvate carboxylase deficiency. People with hyperprolinemia type I often do not show any symptoms even though they have proline levels in their blood between 3 and 10 times the normal level. Some individuals with hyperprolinemia type I exhibit seizures, intellectual disability, or other neurological or psychiatric problems. Hyperprolinemia type II results in proline levels in the blood between 10 and 15 times higher than normal, and high levels of a related compound called pyrroline-5-carboxylate. Hyperprolinemia type II has signs and symptoms that vary in severity and is more likely than type I to involve seizures or intellectual disability.

Nicotinic acid, also known as niacin or vitamin B3, is a water-soluble vitamin whose derivatives such as NADH, NAD, NAD+, and NADP play essential roles in energy metabolism in the living cell and DNA repair. The designation vitamin B3 also includes the amide form, nicotinamide or niacinamide. Severe lack of niacin causes the deficiency disease pellagra, whereas a mild deficiency slows down the metabolism decreasing cold tolerance. The recommended daily allowance of niacin is 2-12 mg a day for children, 14 mg a day for women, 16 mg a day for men, and 18 mg a day for pregnant or breast-feeding women. It is found in various animal and plant tissues and has pellagra-curative, vasodilating, and antilipemic properties. The liver can synthesize niacin from the essential amino acid tryptophan, but the synthesis is extremely slow and requires vitamin B6; 60 mg of tryptophan are required to make one milligram of niacin. Bacteria in the gut may also perform the conversion but are inefficient.

2-Hydroxyglutarate exists in 2 isomers: L-2-hydroxyglutarate acid and D-2-hydroxyglutarate. Both the D and the L stereoisomers of hydroxyglutaric acid (EC 1.1.99.2) are found in body fluids. In humans it is part of butanoate metabolic pathway and can be produced by phosphoglycerate dehydrogenase (PHGDH). More specifically, the enzyme PHGDH catalyzes the NADH-dependent reduction of ?-ketoglutarate (AKG) to D-2-hydroxyglutarate (D-2HG). 2-hydroxyglutarate is also the product of gain-of-function mutations in the cytosolic and mitochondrial isoforms of isocitrate dehydrogenase (IDH). Additionally, 2-hydroxyglutarate can be converted to ?-ketoglutaric acid through the action of 2-hydroxyglutarate dehydrogenase (HGDH). Humans have to variants of this enzyme: D-2-hydroxyglutarate dehydrogenase (D2HGDH) and L-2-hydroxyglutarate dehydrogenase (L2HGDH). A deficiency in either of these two enzymes can lead to a disease known as 2-hydroxyglutaric aciduria. L-2-hydroxyglutaric aciduria (caused by loss of L2HGDH) is chronic, with early symptoms such as hypotonia, tremors, and epilepsy declining into spongiform leukoencephalopathy, muscular choreodystonia, mental retardation, and psychomotor regression. D-2-hydroxyglutaric aciduria (caused by loss of D2HGDH or gain of function of IDH) is rare, with symptoms including cancer, macrocephaly, cardiomyopathy, mental retardation, hypotonia, and cortical blindness. 2-hydroxyglutarate was the first oncometabolite (or cancer-causing metabolite) to be formally named or identified. In cancer it is either produced by overexpression of phosphoglycerate dehydrogenase (PHGDH) or is produced in excess by gain-of-function mutations in the cytosolic and mitochondrial isoforms of isocitrate dehydrogenase (IDH). IDH is part of TCA cycle and is generated in high abundance when IDH is mutated. 2-hydroxyglutarate is sufficiently similar in structure to 2-oxogluratate (2OG) that it is able to inhibit a range of 2OG-dependent dioxygenases, including histone lysine demethylases (KDMs) and members of the ten-eleven translocation (TET) family of 5-methylcytosine (5mC) hydroxylases. This inhibitory effect leads to alterations in the hypoxia induced factor (HIF)-mediated hypoxic response and alterations in gene expression through global epigenetic remodeling. The net effect is that 2-hydroxyglutarate causes a cascading effect that leads genetic perturbations and malignant transformation. Furthermore, 2-hydroxyglutarate is found to be associated with glutaric aciduria II, which is also an inborn error of metabolism. 2-Hydroxyglutarate has also been found to be a metabolite in Aspergillus (PMID: 6057807).

An amino-acid betaine that is butanoate substituted with a hydroxy group at position C-3 and a trimethylammonium group at C-4." []

Methionine (Met), also known as L-methionine, is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. Methionine is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Methionine is found in all organisms ranging from bacteria to plants to animals. It is classified as an aliphatic, non-polar amino acid. Methionine is an essential amino acid (there are 9 essential amino acids), meaning the body cannot synthesize it, and it must be obtained from the diet. It is required for normal growth and development of humans, other mammals, and avian species. In addition to being a substrate for protein synthesis, methionine is an intermediate in transmethylation reactions, serving as the major methyl group donor in vivo, including the methyl groups for DNA and RNA intermediates. Methionine is a methyl acceptor for 5-methyltetrahydrofolate-homocysteine methyltransferase (methionine synthase), the only reaction that allows for the recycling of this form of folate, and is also a methyl acceptor for the catabolism of betaine. Methionine is the metabolic precursor for cysteine. Only the sulfur atom from methionine is transferred to cysteine; the carbon skeleton of cysteine is donated by serine (PMID: 16702340 ). There is a general consensus concerning normal sulfur amino acid (SAA) requirements. WHO recommendations amount to 13 mg/kg per 24 h in healthy adults. This amount is roughly doubled in artificial nutrition regimens. In disease or after trauma, requirements may be altered for methionine, cysteine, and taurine. Although in specific cases of congenital enzyme deficiency, prematurity, or diminished liver function, hypermethioninemia or hyperhomocysteinemia may occur, SAA supplementation can be considered safe in amounts exceeding 2-3 times the minimum recommended daily intake. Apart from some very specific indications (e.g. acetaminophen poisoning) the usefulness of SAA supplementation is not yet established (PMID: 16702341 ). Methionine is known to exacerbate psychopathological symptoms in schizophrenic patients, but there is no evidence of similar effects in healthy subjects. The role of methionine as a precursor of homocysteine is the most notable cause for concern. Acute doses of methionine can lead to acute increases in plasma homocysteine, which can be used as an index of the susceptibility to cardiovascular disease. Sufficiently high doses of methionine can actually result in death. Longer-term studies in adults have indicated no adverse consequences of moderate fluctuations in dietary methionine intake, but intakes higher than 5 times the normal amount resulted in elevated homocysteine levels. These effects of methionine on homocysteine and vascular function are moderated by supplements of vitamins B-6, B-12, C, and folic acid (PMID: 16702346 ). When present in sufficiently high levels, methionine can act as an atherogen and a metabotoxin. An atherogen is a compound that when present at chronically high levels causes atherosclerosis and cardiovascular disease. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of methionine are associated with at least ten inborn errors of metabolism, including cystathionine beta-synthase deficiency, glycine N-methyltransferase deficiency, homocystinuria, tyrosinemia, galactosemia, homocystinuria-megaloblastic anemia due to defects in cobalamin metabolism, methionine adenosyltransferase deficiency, methylenetetrahydrofolate reductase deficiency, and S-adenosylhomocysteine (SAH) hydrolase deficiency. Chronically elevated levels of methionine in infants can lead to intellectual disability and other neurological problems, delays in motor skills, sluggishness, muscle weakness, and liver problems. Many individuals with these metabolic disorders tend to develop cardiovascular disease later in life. Studies on feeding rodents high levels of methionine have shown that methionine promotes atherosclerotic plaques independently of homocysteine levels (PMID: 26647293 ). A similar study in Finnish men showed the same effect (PMID: 16487911 ).

trans-Aconitic acid, also known as trans-aconitate or (e)-aconitic acid, belongs to the class of organic compounds known as tricarboxylic acids and derivatives. These are carboxylic acids containing exactly three carboxyl groups. trans-Aconitic acid exists in all living species, ranging from bacteria to humans. trans-Aconitic acid is a dry, musty, and nut tasting compound. Outside of the human body, trans-aconitic acid has been detected, but not quantified in several different foods, such as garden tomato fruits, root vegetables, soy beans, and rices. trans-Aconitic acid is normally present in human urine, and it has been suggested that is present in larger amounts with Reye's syndrome and organic aciduria. trans-Aconitic acid in the urine is a biomarker for the consumption of soy products. trans-Aconitic acid is a substrate of enzyme trans-Aconitic acid 2-methyltransferase (EC2.1.1.144).

D-Malic acid is found in herbs and spices. This enantiomer of rare occurrence; reported from fruits and leaves of Hibiscus sabdariffa (roselle) although there are many more isolations of malic acid with no opt. rotn. given and some may be of the R-for

Adenosine is a nucleoside that is composed of adenine and D-ribose. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. For instance, adenosine plays an important role in energy transfer as adenosine triphosphate (ATP) and adenosine diphosphate (ADP). It also plays a role in signal transduction as cyclic adenosine monophosphate (cAMP). Adenosine itself is both a neurotransmitter and potent vasodilator. When administered intravenously adenosine causes transient heart block in the AV node. Due to the effects of adenosine on AV node-dependent supraventricular tachycardia, adenosine is considered a class V antiarrhythmic agent. Overdoses of adenosine intake (as a drug) can lead to several side effects including chest pain, feeling faint, shortness of breath, and tingling of the senses. Serious side effects include a worsening dysrhythmia and low blood pressure. When present in sufficiently high levels, adenosine 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 adenosine are associated with adenosine deaminase deficiency. Adenosine is a precursor to deoxyadenosine, which 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.

Dodecanedioic acid is an aliphatic dicarboxylic acid containing 12 carbon atoms. More formally it is an alpha,omega-dicarboxylic acid with both the first and last carbons of the aliphatic chain having carboxylic acids. Dodecanedioic acid is water soluble. It can be produced in yeast and fungi through the oxidation of dodecane via fungal peroxygenases (PMID: 27573441). High levels of dodecanedioic acid is an indicator of hepatic carnitine palmitoyltransferase I (CPT IA) deficiency (PMID: 16146704). CPT IA deficiency is characterized by hypoketotic dicarboxylic aciduria with high urinary levels of dodecanedioic acid. It is thought that carnitine palmitoyltransferase I may play a role in the uptake of long-chain dicarboxylic acids by mitochondria after their initial shortening by beta-oxidation in peroxisomes (PMID: 16146704). CPT IA deficiency is characterized by acute encephalopathy with hypoglycemia and hepatomegaly.