Methyleugenol is a natural chemical compound and belongs to the phenylpropanoid family, a class of organic compounds synthesised by the plant kingdom (Cassia, Eucalyptus. Ginger, Myristica fragrans, Melaleuca alternifolia, Mentha piperita, Sassafras albidum, Vanilla planifolia...). 

It is used in the following products:

• air care products
• biocides
• disinfectants
• pest control products
• perfumes and fragrances
• transparencies and waxes
• textile treatment products
• colorants
• cosmetics
• personal care products

Methyleugenol  is found, as phenylpropanoid, in numerous herbs and spices and in particular in basil. It is present above all in young basil seedlings, that is those that are less than 10 cm in height. It is classified by the European Union Scientific Committee on Food as a genotoxic carcinogen. May cause damage to the human colon (1).

Experiments on rats by Chinese researchers have found the inhibition of excitatory synaptic transmission in the central respiratory unit (2).

The dangerousness of this component in basil, it seems to understand, also depends on the quantity assumed (3) and on the role that nevadensin, another component of basil, plays as a contrast to the Methyleugenol  (4).

On the other hand, Methyleugenol  has been shown to have antiallergic and anti-inflammatory effects, at the concentrations tested (0-100 microns) (5).

The most relevant studies on this chemical compound have been selected with a summary of their contents:

Methyleugenol  studies

• Molecular Formula: C₁₁H₁₄O₂
• Linear Formula H₂C=CHCH₂C₆H₃(OCH₃)₂
• Molecular Weight: 178.231 g/mol
• UNII: 29T9VA6R7M
• CAS: 93-15-2
• EC Number: 202-223-0
• FEMA Number: 2475
• PubChem Substance ID 24901119
• MDL number MFCD00008652
• Council of Europe no. 185
• Beilstein Registry Number 1910871

Synonyms:

• 4-Allyl-1,2-dimethoxybenzene
• Eugenol methyl ether
• 4-Allyl-1,2-dimethyoxybenzene
• Eugenyl methyl ether
• 3,4-Dimethoxyallylbenzene
• 3-(3,4-dimethoxyphenyl)-1-propene
• 4-Allylveratrole
• 4-Allylveratrol
• 1,2-dimethoxy-4-(prop-2-en-1-yl)benzene
• Benzene, 1,2-dimethoxy-4-(2-propen-1-yl)-
• methyl-eugenol
• Eugenol methylether
• Methyleugenol,(S)
• Eugenol-methyl ether
• Methy l eugenyl ether
• Methyleugenol (4-Allyl-1,2-dimethoxybenzene)
• 1,2-Dimethoxy-4-(2-propen-1-yl)benzene
• O-Methyleugenol
• 1,2-dimethoxy-4-prop-2-enylbenzene
• 1-(3,4-Dimethoxyphenyl)-2-propene
• Benzene, 1,2-dimethoxy-4-(2-propenyl)-
• 1,2-Dimethoxy-4-allylbenzene
• 1,2-Dimethoxy-4-allyl benzene
• 2-Methoxy-4-propenylphenol methyl ether
• 1, 2-Dimethoxy-4-(2-propenyl)benzene
• 4-Allyl-1, 2-dimethoxybenzene
• 1-(3, 4-Dimethoxyphenyl)-2-propene
• Dimethoxy-4-(2-propenyl)benzene
• O-Methyl eugenol
• 4-allyl-1,2-dimethoxy-benzene
• Eugenol methyl
• 3,4-Dimethoxyallyl benzene
• Allyl-1,2-dimethoxybenzene
• Benzene,2-dimethoxy-4-(2-propenyl)-
• Benzene, 4-allyl-1,2-dimethoxy-
• 1,3,4-Eugenol methyl ether
• Methyl eugenol ether
• Veratrole methyl ether
• 1,2-Dimethoxy-4-(2-propenyl)benzene
• 1-Allyl-3,4-dimethoxybenzene
• Methyl eugenyl ether

(1) Groh IA, Rudakovski O, Gründken M, Schroeter A, Marko D, Esselen M.  Arch Toxicol. 2016 Methyleugenol and oxidative metabolites induce DNA damage and interact with human topoisomerases.  Nov;90(11):2809-2823. doi: 10.1007/s00204-015-1625-3. 

Abstract. Methyleugenol is a substituted alkenylbenzene found in several herbs and spices. It is classified by the European Union's Scientific Committee on Food as a genotoxic carcinogen. We addressed the biological mechanism of the genotoxic properties of methyleugenol and its oxidative metabolites. Methyleugenol and the oxidative metabolites significantly enhanced the DNA damage in human colon carcinoma cells (HT29). Methyleugenol did not affect the protein status of γH2AX, a biomarker of DNA double-strand breaks, whereas its metabolites methyleugenol-2',3'-epoxide and 3'-oxomethylisoeugenol significantly increased the cellular phosphorylated H2AX level. Both of these metabolites also showed a significant induction of micronuclei in HT29 cells. Furthermore, we investigated whether topoisomerase interaction contribute to the observed effect on DNA integrity. Methyleugenol-2',3'-epoxide and 3'-oxomethylisoeugenol inhibited the activity of recombinant topoisomerase I. In HT29 cells, neither methyleugenol nor the metabolites affected the level of topoisomerase protein bound to DNA, excluding a topoisomerase poisoning mode of action. In addition, 3'-oxomethylisoeugenol potently diminished the level of camptothecin-stabilized topoisomerase I/DNA intermediates and camptothecin-induced DNA strand breaks. In conclusion, it could be suggested that 3'-oxomethylisoeugenol may also interact with classical or food-borne topoisomerase I poisons, diminishing their poisoning effectiveness.

(2) Hou L, Zhou X, Zhang M, Liu Z, Zhang G.   Zhonghua Yi Xue Za Zhi. Effects of Methyleugenol on central respiratory drive to inspiratory-activated airway vagal preganglionic neurons.   2015 Mar 31;95(12):933-7. 

Abstract. Objective: To explore the effects of methyleugenol (MEG) on central respiratory drive to inspiratory-activated airway vagal preganglionic neurons (IA-AVPNs)....Conclusion: MEG inhibits central respiratory drive to IA-AVPNs through inhibiting excitatory synaptic transmission.

(3) Alhusainy W, Williams GM, Jeffrey AM, Iatropoulos MJ, Taylor S, Adams TB, Rietjens IM. The natural basil flavonoid nevadensin protects against a methyleugenol-induced marker of hepatocarcinogenicity in male F344 rat.   Food Chem Toxicol. 2014 Dec;74:28-34. doi: 10.1016/j.fct.2014.08.016. 

(4) Alhusainy W1, Paini A, Punt A, Louisse J, Spenkelink A, Vervoort J, Delatour T, Scholz G, Schilter B, Adams T, van Bladeren PJ, Rietjens IM.  Identification of nevadensin as an important herb-based constituent inhibiting estragole bioactivation and physiology-based biokinetic modeling of its possible in vivo effect.  Toxicol Appl Pharmacol. 2010 Jun 1;245(2):179-90. doi: 10.1016/j.taap.2010.02.017

(5) Tang F, Chen F, Ling X, Huang Y, Zheng X, Tang Q, Tan X. Inhibitory effect of methyleugenol on IgE-mediated allergic inflammation in RBL-2H3 cells. Mediators Inflamm. 2015;2015:463530. doi: 10.1155/2015/463530. 

Abstract. Allergic diseases, such as asthma and allergic rhinitis, are common. Therefore, the discovery of therapeutic drugs for these conditions is essential. Methyleugenol (ME) is a natural compound with antiallergic, antianaphylactic, antinociceptive, and anti-inflammatory effects. This study examined the antiallergic effect of ME on IgE-mediated inflammatory responses and its antiallergy mechanism in the mast cell line, RBL-2H3. We found that ME significantly inhibited the release of β-hexosaminidase, tumor necrosis factor- (TNF-) α, and interleukin- (IL-) 4, and was not cytotoxic at the tested concentrations (0-100 μM). Additionally, ME markedly reduced the production of the proinflammatory lipid mediators prostaglandin E2 (PGE2), prostaglandin D2 (PGD2), leukotriene B4 (LTB4), and leukotriene C4 (LTC4). We further evaluated the effect of ME on the early stages of the FcεRI cascade. ME significantly inhibited Syk phosphorylation and expression but had no effect on Lyn. Furthermore, it suppressed ERK1/2, p38, and JNK phosphorylation, which is implicated in proinflammatory cytokine expression. ME also decreased cytosolic phospholipase A2 (cPLA2) and 5-lipoxygenase (5-LO) phosphorylation and cyclooxygenase-2 (COX-2) expression. These results suggest that ME inhibits allergic response by suppressing the activation of Syk, ERK1/2, p38, JNK, cPLA2, and 5-LO. Furthermore, the strong inhibition of COX-2 expression may also contribute to the antiallergic action of ME. Our study provides further information about the biological functions of ME.