Table 1.
Clusters and odors related to each cluster (Domain classification is based on Mori and Sakano [31]; summarized using Mori et al. [30] and Mori and Sakano [31]).
| Domain | Cluster | Examples of the Odorous Chemical Compounds, which Activated the Cluster | Odor Quality |
|---|---|---|---|
| Dorsal (DI) |
A | Fatty acids and alkylamines [31]. Aliphatic acids, aliphatic aldehydes as well as “the subsets of these odorants with a similar carbon chain length” [30]. Diketones, benzaldehyde, and benzoic acid; common features are “a carboxyl group (-COOH), a diketone group (-(CO)(CO)-), or an ester group (-COO-)”. | Fatty Rancid sour pungent |
| Dorsal (DII) |
B | Aliphatic alcohols, aliphatic ketones, and phenyl ethers [31]. “Aliphatic alcohols with relatively long carbon chain and to a wide range of aliphatic ketones”. Subsets of esters. Anisole and its derivatives with a methoxy group (-O-CH3). Combination “of elongated carbon chain structures with a hydroxyl group (-OH), an alkoxyl group (-O-R), or a carbonyl group (>C=O)”. | Floral Fruity Green and grassy Anisic |
| Dorsal DII |
C | Phenols and phenyl ethers [31]. “Phenol family odorants, molecules having a hydroxyl group attached to the benzene ring”. Phenyl ethers; “molecular features of a benzene ring with hydroxyl group, a methoxy group, or an ethoxy group”. | Phenolic Medicinal Spicy Ethereal |
| D | Aliphatic and aromatic ketones [31]; “responses to a variety of ketones: aliphatic ketones, aliphatic-aromatic ketones, diketones, and cyclic ketones”. | Spicy Minty |
|
| Lateral/ventral | E | Not specified in Mori et al. [30] nor in Mori and Sakano [31]; weak responses to ethers [30]. | |
| F | Aliphatic “ketones, phenyl ethers, diketones, aliphatic-aromatic ketones, and cyclic ketones”. | ||
| G | Phenyl “ethers, diketones, aliphatic ketones with relatively short side chains, aliphatic-aromatic ketones, cyclic ketones and ethers”. | ||
| H | “Benzene-family odorants”. No response “or only a weak response to cyclic terpene hydrocarbons”. Some “respond to open-chain hydrocarbons”. “benzene derivatives with a polar functional group, such as anisole”, phenol, benzaldehyde, or acetophenone. | Gassy and kerosene-like odor | |
| I | “respond to at least one of the cyclic terpene hydrocarbons”. Subset of benzene-family odorants; cyclic terpene ketones, cyclic terpene alcohols | Citrusy Woody |
|
| Dorsal DII |
J | Thiazoles and thiazolines [31]. |
*: Cited parts (““) are from Mori et al. [30].