Material guide · 180
Material guide: lemongrass oil — two species under one name, and West Indian lemongrass is not from the West Indies
· 18 min read
CAS 8007-02-1, 88 suppliers. Its systematic name field is not one name but two: cymbopogon citratus dc and cymbopogon flexuosus oil. The notes field spends a paragraph explaining why — lemongrass oil comes from two distinct Cymbopogon species, one native to the East Indies (C. flexuosus) and one, C. citratus, that the catalogue itself says carries the somewhat confusing name West Indian lemongrass. It is not from the West Indies; it was simply transplanted worldwide. Better still, the TSCA definition on the last line of that same paragraph names only one of the two species. A 2021 Egyptian paper measured one field across four seasons: oil yield ran from 0.15% in winter to 0.46% in spring, and GC-MS identified 61, 25, 50 and 63 components in spring, summer, autumn and winter — same grass, a 2.5-fold spread in component count. One more database detail: CAS 5392-40-5 holds two records, one for citral itself (135 suppliers, 12 hours substantivity) and one for terpeneless litsea cubeba oil (3 suppliers, 24 hours). Strip the terpenes and the catalogue considers it to be the compound.
About a 4 minute read.
Too long, didn't read
- Name: lemongrass oil, CAS 8007-02-1, 88 suppliers
- The systematic name field holds two botanical names:
cymbopogon citratus dc and cymbopogon flexuosus oil - Odor type citrus; odor: fresh, sweet, lemon, grassy, green, bois de rose, tomato leaf, floral, citrus
- Substantivity 92 hours, flash point > 91.67 °C, shelf life 24 months, specific gravity 0.887–0.899
- The regulatory field holds FEMA GRAS and nothing else
- The notes field calls West Indian lemongrass a somewhat confusing name, in those words
One name, two species
Most natural oils carry a single botanical name. This one reads:
cymbopogon citratus dc and cymbopogon flexuosus oil
Two species, joined by an and. The notes field then spends a paragraph on why:
Lemongrass oil is produced from two distinctly different species of Cymbopogon. One is native to the East Indies, where it grows wild, and is now cultivated in a relatively limited area of western India. This plant is Cymbopogon flexuosus, and only the cultivated plants are distilled. The other plant, Cymbopogon citratus, is probably native to Ceylon and parts of the East Indies but is now found only under cultivation. Unlike C. flexuosus, citratus has become widely distributed throughout the world, and it has been given the somewhat confusing name of West Indian lemongrass.
West Indian lemongrass is not from the West Indies. It is an eastern grass that picked up the name by being transplanted to the Caribbean. Whoever wrote the catalogue entry evidently thought this needed saying, which is why the phrase "somewhat confusing" is in there at all.
The notes field then lists where it grows now: Africa, the Congo, Angola, equatorial Africa, Madagascar, the Comoros, Central America, the West Indies, Haiti, Jamaica, South America, and Formosa, Indo-China, Indonesia, Malaya. That is a colonial-era crop map.
The last line of the same paragraph is the TSCA definition: cymbopogon citratus, gramineae. A whole paragraph about two species, and the formal definition names one
of them.
CAS 8007-02-1 holds three records in the database: lemongrass oil (88 suppliers), Guatemalan lemongrass oil (21) and Chinese lemongrass oil (9). The origins were split out. The species were not.
One field, four seasons, a 2.5-fold spread in component count
In 2021 Madi and colleagues at Cairo University measured C. citratus cultivated in Egypt, comparing oils from four harvest seasons (PMID 31960718).
Yield: hydrodistillation of fresh leaves gave 0.15% to 0.46% (w/w), highest in spring, lowest in winter, a threefold range.
Component count: GC-MS identified 61, 25, 50 and 63 components in the spring, summer, autumn and winter samples. Same species, same field, and the summer sample resolved 40% as many components as the winter one.
Composition: every sample was dominated by oxygenated monoterpenes, at 73.22% to 89.32%. Citral content was highest in the autumn and summer samples.
The authors also tested acetylcholinesterase inhibition. The winter oil was moderate (IC50 2.86 ± 0.17 mg/mL) against physostigmine at 0.012 mg/mL, with the other samples weaker (IC50 2.86–5.40 mg/mL).
For a buyer the reading is direct: the words "lemongrass oil" specify neither species nor season, and both move the composition. The COA is the answer for that drum.
Strip the terpenes and the catalogue calls it citral
CAS 5392-40-5 holds two records in the database:
| Record | Suppliers | Odor type | Odor | Substantivity |
|---|---|---|---|---|
| Citral | 135 | citrus | sharp, lemon, sweet, fresh, juicy | 12 hours |
| litsea cubeba oil terpeneless | 3 | citrus | sweet, lemon, citrus | 24 hours |
A natural oil with its terpenes removed, filed under a pure compound's CAS. The catalogue's judgement is that what remains is citral.
The two records disagree on substantivity, 12 hours against 24. Same CAS, two numbers. Same CAS, different odor type measured that pattern.
The oil outlasts its own main component
Line up the substantivity figures across the citral family:
| Material | Suppliers | Substantivity (hours) | Shelf life |
|---|---|---|---|
| Citral | 135 | 12 | 24 months |
| Litsea cubeba oil | 71 | 44 | 12 months |
| Lemongrass oil | 88 | 92 | 24 months |
| Guatemalan lemongrass oil | 21 | 99 | (empty) |
Citral on its own gets 12 hours. Lemongrass oil, which is mostly citral, gets 92 — nearly eight times longer.
Other components in a natural oil holding back evaporation is expected. The shelf life column is the one that jumps around: 12 months for litsea cubeba, 24 for lemongrass, and 24 for citral itself. The ginger root oil guide noted that oxidised citral is a sensitiser, and it is one of the 26 allergens the EU requires by name. Against that risk, 24 months is an unopened figure, not an opened one.
Buying and storing
Eighty-eight suppliers, easy to find. More to ask than usual:
- Ask which species. C. flexuosus (East Indian) and C. citratus (West Indian) are two grasses under one CAS. Write the botanical name if it matters.
- Ask about harvest season. The paper above measured both component count and yield moving with it.
- Ask for citral content. That is what it does in a formula, and it decides whether the allergen declaration applies.
- The 24-month shelf life is unopened. Oxidised citral sensitises, so decant on opening, date the bottle, keep it dark and cold.
- Flash point > 91.67 °C is high for a natural oil, which makes shipping and storage easier than for citrus peel oils.
- Specific gravity 0.887–0.899 is a field you can verify yourself on arrival. The optical rotation field is empty for this one.
→ Lemongrass oil in the database: full properties, 88 suppliers and suggested blends.
What this article does not establish
- "West Indian lemongrass is not from the West Indies" is the notes field's own claim, and I did not chase the etymology to a primary source.
- The origin list in the notes field carries no date. Names like Formosa and the Belgian Congo point at a very old source.
- The Egyptian paper is one location in one year, not a survey of lemongrass oil worldwide. The 25-to-63 spread in component count may also carry analytical variation between runs, which the abstract does not separate out.
- Terpeneless litsea cubeba oil sits under citral's CAS and I only describe that, without judging whether the classification is right.
- I attribute "the oil outlasts its main component" to other components holding back evaporation. That is the usual explanation, but these substantivity figures come from different suppliers' blotter records, not from one set of experiments.