How do the chemical characteristics of jasmine vary with species, harvest time, and extraction method? In March 2026, Mohamed S. Yassen and colleagues at Ain Shams University in Egypt published a study comparing the compounds in flowers and extracts from four species. They also examined inhibition of an enzyme called MAO-A by the extracts and its association with their composition.
The background is a need to understand jasmine’s chemical characteristics in detail, both to authenticate perfumery materials and to detect adulteration. After introducing the study’s two main strands, this article considers how to view flowers and absolutes. It was not a study in which people smelled fresh flowers and raw materials side by side to establish the causes of differences in their impressions.
- How Are Concretes and Absolutes Made?
- Analyzing Four Flowers and Two Types of Extract
- A Prominent Flower Compound Is Not Necessarily Abundant in Its Extract
- Even Within Jasmine, Species and Month Matter
- The Second Strand: MAO-A Inhibition by the Extracts
- How Far Can the Authors’ Conclusions Be Taken?
- Summary
- References
How Are Concretes and Absolutes Made?
In this study, the flowers were first soaked in a solvent called hexane to extract their components, after which the solvent was evaporated. The resulting semisolid extract, which also contains plant waxes and other substances, is called a concrete.
Next, the concrete was treated with ethanol, chilled to remove waxes, and finally the ethanol was evaporated. The perfumery material left behind is an absolute. The terms may sound technical, but the process becomes easier to follow if you think of first extracting components from flowers and then separating them further by using differences in solubility.
Compounds emitted from flowers into the air and compounds that dissolve in a solvent differ in how readily they are collected. After extraction, there are also filtration and solvent-removal stages. An absolute’s composition therefore cannot simply be assumed to be a concentrated version of the air around a flower in unchanged proportions.
Analyzing Four Flowers and Two Types of Extract
The four species were Jasminum sambac, Jasminum grandiflorum, Jasminum azoricum, and Jasminum multiflorum. Flowers were collected early in the morning at several sites in Egypt during summer 2022. The researchers examined grandiflorum and azoricum flowers from June through August, and sambac and multiflorum flowers from July through August.
Concretes and absolutes were prepared in the laboratory from the August flowers. Grandiflorum concrete and absolute obtained from a factory were also included for comparison.
The analytical instrument used was GC–MS, which separates a mixture and examines its components’ characteristics to identify them. In addition to analyzing extracts, the team performed headspace analysis: fresh flowers were placed in small vials and compounds entering the space above them were examined.
However, the flower analysis used an instrument setting of 80°C and an equilibration period of 8 minutes before measurement. It did not collect the air around garden flowers at ambient temperature. This heating condition is important when interpreting the results.
A Prominent Flower Compound Is Not Necessarily Abundant in Its Extract
Across the study, 157 compounds were reported. Their identities and relative proportions varied not only by flower species but also by sample form: flower headspace, concrete, or absolute.
Take linalool, a compound associated with floral and fruity scents. In August sambac flowers, its reported relative proportion was 25.41%. In the laboratory-prepared concrete of the same species, it was 0.73%, and it was not detected in the absolute.
Another compound, cis-3-hexenyl acetate, accounted for a large proportion in August sambac flowers but was not detected in the concretes or absolutes examined here. Conversely, compounds different from those prominent in flower headspace accounted for large proportions of the extracts.
The percentages here are relative proportions of the composition reported by instrumental analysis. They do not mean that 25% of the flower’s weight is linalool, or that it accounts for 25% of the perceived scent. Nor does “not detected” prove that the amount is exactly zero; it means the compound could not be confirmed under these measurement conditions.
The flower-headspace and extract profiles obtained under these differing analytical conditions did not match. However, the differences involve not only extraction and purification but also differences in the range of compounds the measurements can capture. This comparison alone cannot separate those contributions, and the numerical differences cannot simply be converted into a percentage lost during extraction.
Even Within Jasmine, Species and Month Matter
Differences also appeared between flower-headspace samples. The relative proportion of linalool in grandiflorum changed from 14.03% in June to 21.71% in July and 38.19% in August. In sambac, by contrast, it was 63.06% in July and 25.41% in August. Even for the same compound, monthly patterns were not the same in the two species.
In multiflorum, linalool was not detected, while another compound, nerolidol, accounted for a large proportion. Different combinations of compounds therefore lie within the single name “jasmine.”
The team also used statistical analyses that compare many compounds together and place compositionally similar samples close to one another. These results likewise showed differences by species, sample form, and harvest month. Because collection sites differed between species, however, not all differences can be attributed to species alone. Comparisons with factory products also include differences in suppliers and production conditions.
The Second Strand: MAO-A Inhibition by the Extracts
Using human MAO-A, an enzyme involved in breaking down neurotransmitters and other substances, the team measured in vitro how strongly the extracts suppressed its activity. The concretes and absolutes examined showed inhibitory activity, and in corresponding sample pairs the absolutes reduced enzyme activity by half at lower concentrations.
Statistical comparison of mixture composition with inhibitory activity also found positive associations for several compounds, including linalool, indole, and benzyl acetate. However, these results did not come from testing each compound on its own to establish its action. Further work is needed to determine which compounds contribute, by how much, and whether combinations of compounds are involved.
The authors position these findings as a starting point for future mechanistic research and also mention possible applications to depression. At the same time, they state that in-vivo and clinical validation is needed. What was tested here was a reaction between enzymes and extracts, not the mood of people smelling jasmine or an antidepressant effect in humans.
How Far Can the Authors’ Conclusions Be Taken?
From the chemical analysis, the authors conclude that August is the best harvest time and link characteristic grandiflorum compounds with its value in perfumery. However, the study contains no human sensory evaluation. Chemical comparisons from these locations, this year, and these harvest months cannot establish superiority of scent or the best month in other growing regions.
The original paper’s conclusion also describes the headspace method as “heat-free,” whereas the methods section states that measurements were made at 80°C. This article follows the methods section and distinguishes the measurement from directly capturing the scent of a flower blooming at ambient temperature. Potential usefulness for identifying components is also a different stage from demonstrated accuracy as a practical adulteration-detection method.
Summary
The contribution of this study lies in not treating jasmine as a single scent, but comparing chemical characteristics by species, harvest month, and sample form, and examining their association with enzyme inhibition by extracts. It provides information for characterizing raw materials and candidates for subsequent mechanistic research. It has not established the causes of differences in perceived scent or therapeutic effects in humans.
Broadening How We Look at Fragrance Materials
Taking the study as a starting point, we might view an absolute as more than simply “the flower’s scent made stronger,” paying attention to the plant species, harvest time, and extraction process too. This is an interpretation of fragrance materials developed from the chemical comparison, not a conclusion established through scent testing in this study.
Rather than seeing the difference between a fresh flower and a raw material merely as a failure to reproduce the flower, consider which aspect of the flower you sense in that material. Asking that question may let you enjoy fragrances sharing the name jasmine in finer detail.
References
Authors: Mohamed S. Yassen, Iriny M. Ayoub, Sherweit H. El-Ahmady, Abdel Nasser B. Singab
Article title: Comparative analysis of flower volatiles from four Jasminum species growing in Egypt using multivariate analysis
Journal: Scientific Reports 16, 8947 (2026)
First publication: March 11, 2026 (publisher’s version-of-record date: March 13)
DOI: 10.1038/s41598-026-39688-w
Original full text: Publisher’s article page
Original study license: CC BY 4.0
