Chemistry of Natural Products (PHG 322)

A substance like oil of anise that becomes solid at temperatures below room temperature (15°C).

The point at which a substance changes from a liquid to a solid state. For oil of anise, this is below room temperature (15°C).

The solidification point of oil of rose is 18°C, meaning it changes from a liquid to a solid state below this temperature.

Oil of lemon, unlike many other essential oils, leaves a thick, sticky residue when it evaporates.

A substance that does not readily evaporate at room temperature, like oil of lemon, which leaves a gummy residue behind.

Ketones are a class of organic compounds that contain a carbonyl group (C=O) bonded to two alkyl groups. This chemical structure is responsible for their pleasant smell.

Nitriles are organic compounds containing a cyano group (C≡N) attached to an alkyl or aryl group. They possess a distinctive odour.

Isomers are molecules with the same molecular formula but different spatial arrangements of atoms. This structural difference can lead to variations in their physical and chemical properties, including odor.

d-Carvone and l-Carvone are examples of enantiomers, a type of isomer where molecules are mirror images of each other. Their different 3D structures influence their scent perception.

The specific spatial arrangement of atoms within a molecule, known as its stereochemistry, can significantly influence its odor. This is because the shape of the molecule impacts how it interacts with odor receptors in our nose.

Essential oils that dissolve better in weak alcohol solutions.

A smaller amount of this type of essential oil is needed to achieve the same intensity of aroma.

Essential oils containing a higher proportion of oxygen-containing compounds.

The characteristic scent of an essential oil

The process of dissolving an essential oil in alcohol.

Essential oils are classified into 'groups' based on the number of carbon atoms in their molecules. These groups are named using prefixes like "Mono", "Di", and "Tri", indicating 10, 20, and 30 carbon atoms, respectively.

Each group of essential oils includes both oxygenated and non-oxygenated compounds. Non-oxygenated compounds are often called hydrocarbons.

The oxygenated compounds within an essential oil group are generally responsible for the characteristic scent or aroma of the oil.

Essential oils are classified into 'groups' based on the number of carbon atoms in their molecules, with prefixes indicating carbon count: "Mono" - 10, "Di" - 20, "Tri" - 30. Within each group, there are both oxygenated and non-oxygenated compounds, with oxygenated compounds primarily responsible for the oil's scent.

Essential oils contain both oxygenated and non-oxygenated components. Oxygenated components contribute to the oil's aroma, while non-oxygenated components are primarily hydrocarbons.

Terpenoid content in essential oils can lead to a decrease in the oil's aroma due to its impact on the volatile compounds responsible for the scent.

A high concentration of terpenoids in essential oils makes them less soluble in low-strength alcohols, leading to a separation of the oil and alcohol.

Elevated terpenoid content in an essential oil can accelerate the process of resinification, causing the oil to thicken and form a sticky residue.

Terpeneless oils are produced by removing terpenes from natural oils. This process makes the oils more stable and less prone to changes over time.

While terpeneless oils offer greater stability, they are usually more expensive than their natural counterparts due to the additional processing involved.

A separation technique used to isolate components of a mixture based on their differing affinities for a stationary phase (silica gel) and a mobile phase (solvents). The mobile phase moves through the stationary phase, carrying different components at different rates, resulting in their separation.

A solvent commonly used in column chromatography to elute (separate) hydrocarbons, which are non-polar compounds. Its low polarity helps to weakly interact with the stationary phase and allow hydrocarbons to move faster.

A solvent commonly used in column chromatography to elute oxygenated compounds, which are more polar. Its higher polarity allows it to interact more strongly with the stationary phase, slowing down the oxygenated compounds and separating them from hydrocarbons.

A technique used to selectively isolate oxygenated compounds from a mixture by using a solvent (dilute alcohol) that preferentially interacts with these compounds. The solvent is then removed by distillation, leaving behind the concentrated oxygenated compounds.

Separation technique used to purify liquids by vaporizing them and then condensing the vapor, removing impurities. The compounds with different boiling points vaporize and condense at different temperatures, leading to their separation.