pediaLemongrass oil is an essential oil with a sharp, fresh lemon scent obtained through steam distillation of the leaves of Cymbopogon citratus (DC.) Stapf (Poaceae/Gramineae family), a tropical grass plant native to Southeast Asia. While lemongrass, a perennial tropical grass plant, is widely used as a culinary herb in Thai and Vietnamese cuisines, its essential oil occupies an important position in the aromatherapy and cosmetic industries. Lemongrass oil, with citral as its main component (65-85%), has been the subject of in vitro studies in scientific literature; additionally, the components citral and geraniol are being researched in the context of insect repellent properties.
This article is not a product promotion. The information contained herein does not contain any therapeutic claims.
Botanical source and traditional use
Cymbopogon citratus (DC.) Stapf belongs to the Poaceae (grass) family and is a perennial tropical grass plant native to Southeast Asia (India, Sri Lanka, Myanmar). It is characterized by long, narrow, light green leaves that can reach 1–2 meters in height. When the leaves are crushed, they emit an intense lemon scent — this fragrance is the source of the citral component.
The Cymbopogon genus comprises more than 55 species. The most important species from a cosmetic and aromatherapy perspective are: C. citratus (West Indian lemongrass), C. flexuosus (East Indian lemongrass — Cochin lemongrass), C. nardus (citronella — mosquito repellent), and C. martinii (palmarosa). Each species has a different chemical profile and scent character.
In Hindu Ayurvedic tradition, lemongrass is known as "bhustrina" or "sera" and has been used in the context of fire, digestive issues, and skin care. It has also been utilized in traditional Southeast Asian practices; these historical and traditional uses belong to a medical (pharmaceutical) context and are outside the scope of this cosmetic monograph.
Chemical profile
Citral: main component (65-85%)
The main component of lemongrass oil is citral, which is actually a mixture of two geometric isomers — geranial (citral a, trans-isomer) and neral (citral b, cis-isomer). Geranial is usually found in higher concentrations than neral. Citral is one of the monoterpene aldehydes and is the primary natural source of lemon scent — it is widely used in the perfumery industry to obtain "lemon notes." In the EU Cosmetic Regulation (EC/1223/2009), citral is listed among 26 components requiring allergen declaration. In cosmetic products exceeding certain concentration thresholds, it must be specifically mentioned in the INCI list.
Other components
Other important components of lemongrass oil include: myrcene (5-15% — aromatic character), geraniol (2-5%), citronellal, limonene, linalool, and geranyl acetate. Myrcene is the source of the oil's "green-herbaceous" undertone note.
Place in scientific literature
Antimicrobial research
In a review published by Shah and colleagues (2011) in the Journal of Advanced Pharmaceutical Technology & Research, the pharmacological properties of C. citratus were comprehensively evaluated. Lemongrass oil has been examined in in vitro studies against gram-positive and gram-negative bacteria, Candida species, and dermatophytes (these in vitro observations do not constitute cosmetic effect claims). In these studies, the prominent component was citral, and the mechanism of interaction at the chemical level with cell membranes is being investigated.
In vitro microbiological studies
Lemongrass oil has been examined in in vitro studies on Candida albicans, Aspergillus species, and dermatophytes (Trichophyton, Microsporum) (these in vitro observations do not constitute cosmetic effect claims). These observations reflect scientific interest in citral chemistry.
Insect repellent property
Lemongrass, a close relative of citronella (C. nardus), is also being researched as a natural mosquito repellent. The components citral and geraniol are used in insect repellent formulations. It is being evaluated as a natural alternative to DEET, although its duration of efficacy is shorter compared to synthetic repellents.
Aromatherapy context
Lemongrass oil is classified in aromatherapy as an "uplifting" and "refreshing" oil. Inhalation studies exist in the context of relaxation and stress, but evidence is still limited.
Safety profile
Citral and contact allergy
Citral is listed among components requiring allergen declaration in the EU Cosmetic Regulation. Contact allergy potential exists — particularly in high concentrations or in oxidized oil, the risk increases. IFRA (International Fragrance Association) has established concentration limits for formulations containing citral.
Skin irritation
Lemongrass oil may cause skin irritation when applied undiluted (neat). In cosmetic formulations, it is typically used at low concentrations (0.5-3%). In sensitive skin types, the risk of irritation is higher — a patch test is recommended.
Phototoxicity
Unlike citrus essential oils, lemongrass oil is not classified as phototoxic — this is a consequence of its steam distillation method (cold-pressed citrus oils carry a phototoxicity risk from furanocoumarins; distilled oils do not contain these components).
Lemongrass oil in soap making
Method of addition and ratio
Lemongrass oil is added during the trace stage in soap making, typically at a ratio of 3-5% of the total oil content. In an alkaline environment, the citral component may undergo chemical transformations such as aldol condensation over time — therefore, there may be slight changes in scent (the fresh lemon note gradually softens, transforming into a more "green-herbaceous" note).
Properties it imparts to soap
Lemongrass oil imparts a sharp, fresh, energetic lemon scent to soap. This fragrance profile is similar to citrus essential oils (orange, lemon) but contains a more "herbal-green" undertone. Scent retention capacity is moderate to good — longer-lasting than cold-pressed citrus oils. Direct color effect on soap is minimal (slight yellowish tone).
Compatible blends
Lemongrass oil creates "tropical refreshing" combinations with mint, "clean-green" with eucalyptus, "flowery-citrus" with lavender, "spicy-warm" with ginger, and "full citrus" with orange.
Frequently asked questions
What is lemongrass oil?
Lemongrass oil is an essential oil obtained through steam distillation of the leaves of Cymbopogon citratus, rich in citral (65-85%).
What is lemongrass oil used for in soap?
It imparts a sharp, fresh lemon scent to soap. It is added at a 3-5% ratio during the trace stage. Its scent retention capacity is superior to citrus oils.
Is lemongrass oil an allergen?
Its main component, citral, is among the components requiring allergen declaration in the EU Cosmetic Regulation. At low concentrations and in fresh oil, the risk is minimal.
Are lemongrass oil and citronella the same?
No. Lemongrass (C. citratus) and citronella (C. nardus) are different species of the same genus. While citronella contains mainly citronellal, lemongrass contains mainly citral. Their fragrance profiles and applications differ.
Chailea products containing this ingredient
- Natural Lemon Grass Soap 100 g
Bibliography
1. Shah, G., et al. (2011). Scientific basis for the therapeutic use of Cymbopogon citratus, stapf (lemon grass). Journal of Advanced Pharmaceutical Technology & Research, 2(1), 3-8. doi:10.4103/2231-4040.79796
2. Ekpenyong, C. E., et al. (2015). Cymbopogon citratus Stapf (DC) extract ameliorates atherogenic cardiovascular risk in diabetes-induced dyslipidemia in rats. British Journal of Medicine and Medical Research.
3. Boukhatem, M. N., et al. (2014). Lemon grass (Cymbopogon citratus) essential oil as a potent anti-inflammatory and antifungal drugs. Libyan Journal of Medicine, 9(1), 25431.