Spring 2009 Newsletter
The Fragrance of Flowers: A Chemist's Quest for Love
It’s spring again…the sun is shining, the air is fresh, and the flowers are blooming! As the sweet smells of spring fill the air, Darren, a love-sick Chemir chemist wondered what makes up those beguiling scents?….and, more importantly, could he impress young ladies with detailed knowledge of the flowery fragrances?
As a faithful advocate of the scientific method, Darren understood there was only one way to find out…
After a trip to the florist, Darren had assembled a beautiful and odor-ific bouquet of wax flowers, genista, and roses. Analysis by headspace gas chromatography with mass spectrometry (headspace GC/MS) yielded the results Darren craved: the identities of the chemicals that synergistically produce the lovely scents of spring.
Wax flowers, or Geraldton wax, (Chamelaucium uncinatum) are native to Western Australia. They are relatively hardy and are most commonly white or mauve. They grow as small to medium shrubs with narrow leaves and tiny bowl-shaped flowers with five rounded petals. They are described as having a citrus or nutty fragrance. When Darren analyzed the volatile components of the wax flowers, he understood the origin of this fragrance. The combination of pinene, camphene, and limonene (Chart 1 and Table 1) provided the pleasing fragrance emanating from these dainty flowers.
Chart 1: Mass Spectra of Volatile Components in Wax Flowers
Table 1: Wax Flowers
Retention Time (Minutes) |
Identity [CAS #] |
Scent |
| 1.91 |
(+)α-pinene [7785-70-8] |
minty |
| 2.77 | β-pinene [127-91-3] |
herbal |
| 3.73 | (+)-camphene [5794-03-6] |
woody |
| 4.41 | (±)-limonene [138-86-3) |
citrus, herbal, camphor |
Genista, also known as French Broom, Cape Broom, or Montpellier Broom, (Genista monspessulana) is a woody perennial shrub, native to the Mediterranean region. The flowers are yellow, and its seeds develop in pods, as it is in the legume family. The presence of ocimene, an unsaturated octenol, and methyl anthranilate account for the woody fragrance of the genista (Chart 2 and Table 2).
Chart 2: Mass Spectra of Volatile Components in Genista
Table 2: Genista
Retention Time (Minutes) |
Identity [CAS #] |
Scent |
| 5.86 | β-ocimene [3338-55-4] |
citrus, tropical, woody |
| 9.19 | 1-octen-3-ol [3391-86-4] |
earthy |
| 14.95 | methyl anthranilate [134-20-3] |
fruity, grape, orange flower |
In the course of his research, Darren was intrigued to find that when genista catches fire, the leaves and seeds release alkaloids poisonous to many large domestic animals. Examples of chemicals in the alkaloid family include cocaine, caffeine, nicotine, morphine, and quinine.
Making a mental note to avoid romantic candlelit dinners with bouquets of genista, Darren continued his laboratory experiment with an investigation into roses, those ancient symbols of love and beauty!
Roses, a perennial flower shrub, are a family of over 100 species that come in a variety of colors. They have sharp prickles, commonly mistaken as thorns. The fragrance of roses has been used to make perfumes for centuries. Darren found the fragrant alcohols geraniol and 1-citronellol as well as Beta-damascenone as major components of the scent of his rose sample.
Armed with this knowledge, a feeling of accomplishment, and a fragrant boutonnière, Darren ventured into the world to meet and woo a special lady… she who enjoys the beauty of fresh flowers and possesses a sense of wonder about the chemistry of volatile chemicals and fragrances!