Alternariol is the mycotoxin produced by Alternaria fungi. It occurs naturally in foodstuffs and is frequently found as contaminant in fruit and grain products. It forms reactive oxygen species and interacts with DNA topoisomerase, thereby generating both single- and double-strand DNA beaks. Alternariol demonstrated dual inhibition of acetylcholinesterase (AChE) and monoamine oxidase (MAO-A) enzymes extracted from whole and five different parts of male albino rat brains; namely: frontal cortex, basal ganglia, cerebellum, pons, medulla oblongata. In vitro studies have suggested that Alternariol may be linked to reduced immune response in case of infections and/or a disturbed balance of the adaptive immune system. Although the absorption appears to be relative low, it is nevertheless important to further clarify the mode of genotoxicity.

Trihydroxychalcone (Isoliquiritigenin, ISL) is a flavonoid found in licorice root and several other plants that displays antioxidant,anti-inflammatory,and antitumor activities as well as hepatoprotection against steatosis-induced oxidative stress. Trihydroxychalcone is a potent antimetastatic agent, which can markedly inhibit the metastatic and invasive capacity of prostate cancer cells. The inhibition of JNK/AP-1 signaling may be one of the mechanisms by which ISL inhibits cancer cell invasion and migration. Trihydroxychalcone has been shown to be a BACE1 inhibitor, which could ameliorate memory impairment in mice, and is expected to be potentially used as a lead compound for further anti-AD reagent development.

Phenformin is a biguanide hypoglycemic agent with actions and uses similar to those of metformin. It activates AMP-activated protein kinase (AMPK) and inhibits mTORC1 signaling. Phenformin used for the treatment of diabetes. Phenformin was removed from the U.S. market 20 years ago because of a high incidence of lactic acidosis. Risk factors for the development of lactic acidosis include renal deficiency, hepatic disease, cardiac disease, and drug interaction such as cimetidine. Phenformin exerts potential anti-neoplastic action.

Angelicin (isopsoralen), is a furocoumarin, occuring in a number of plants belonging to the Umbelliferae family. It acts as a photosensitizer by forming DNA monoadducts. Angelicin is able to inhibit monoamine oxidase (MAO) activities in rat brain mitochondria. Angelicin exerts antineoplastic and antidiabetic properties in animal models.

Rosmarinic acid (α-o-caffeoyl-3,4-dihydroxyphenyllactic acid; RA) is a naturally occurring hydroxylated compound commonly found in species of the subfamily Nepetoideae of the Lamiaceae and Boraginaceae, such as Rosmarinus officinalis, Salvia officinalis, and Perilla frutescens. RA is biosynthesized from the amino acids L-phenylalanine and L-tyrosine by eight enzymes that include phenylalanine ammonia lyase and cinnamic acid 4-hydroxylase. Recently, RA and its derivatives have attracted interest for their biological activities, which include anti-inflammatory, anti-oxidant, anti-angiogenic, anti-tumor, and anti-microbial functions. Clinically, RA attenuates T cell receptor-mediated signaling, attenuates allergic diseases like allergic rhinitis and asthma, and 2,4-dinitrofluorobenzene-induced atopic dermatitis-like symptoms, protects from neurotoxicity, and slows the development of Alzheimer's disease. Rosmarinic Acid seems to be able to suppress 5-lipoxygenase and 5-HETE synthesis (a pro-inflammatory compound in the omega-6 metabolic chain). Rosmarinic acid appeared to be effective in suppressing allergies in a dose-dependent manner, with 30% of the placebo group reporting symptom relief compared to 55.6% of the 50mg group and 70% of the 200mg group.

Indeloxazine is a neuroleptic, originally developed and marketed in Japan. It is indicated to allay autonomic hyperactivity following cerebral infarction, cerebral haemorrhage or atherosclerosis. It was found to be a weak inhibitor of both type A and type B monoamine oxidases. Indeloxazine-induced facilitation of acetylcholine release in frontal cortex is mediated by endogenous 5-HT and involves at least in part cortical 5-HT4 receptors. As a potential teratogen, Indeloxazine must not be consumed or handled by pregnant or nursing women, or by women who might become pregnant. It was removed from the market reportedly for lack of effectiveness.

Bifemelane is a psychotropic drug, was found to inhibit monoamine oxidase (MAO). It inhibited type A MAO (MAO-A) competitively and type B (MAO-B) noncompetitively and it was a more potent inhibitor of MAO-A than of MAO-B. Bifemelane is an antidepressant and cerebral activator that is used in Japan for the treatment of cerebral infarction patients with depressive symptoms, and in the treatment of senile dementia as well. It also appears to be useful in the treatment of glaucoma.

Debrisoquin is an antihypertensive drug having guanethidine-like properties, which inhibits monoamine oxidase (MAO) and does not enter the brain. Debrisoquine was used for the treatment of hypertension. Debrisoquine hydroxylation phenotype has been the most used test in humans to evaluate CYP2D6 activity. Two debrisoquine hydroxylation phenotypes have been described: poor and extensive metabolizers. A group with a very low debrisoquine metabolic ratio within the extensive metabolizers, named ultrarapid metabolizers, has also been distinguished. This CYP2D6 variability can be for a large part alternatively determined by genotyping, which appears to be of clinical importance given CYP2D6 involvement in the metabolism of a large number of commonly prescribed drugs.

Toloxatone is an antidepressant launched in 1984 in France for the treatment of depression. It is a selective reversible inhibitor of MAO-A (RIMA).

Metralindole (Inkazan) is a reversible inhibitor of monoamine oxidase A (RIMA) which was used in Russia as an antidepressant. Inkasan (3-methyl-8-methoxy-3H, 1,2,5,6- tetrahydropyrazine /1.2.3-ab/-beta-carboline hydrochloride) has pharmacological properties characteristic of antidepressants. The clinical antidepressant effect of inkasan is combined with stimulating action. The drug is primarily indicated for patients in whom adynamic (anergic) disturbances are predominant in the clinical picture of depression.