Therapeutic Uses
- Antimicrobial, Antifungal, and Antiviral Properties – The essential oils derived from the steam-distillation of lemongrass leaves have shown activity against 20 different bacteria (including Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Enterobacter faecalis, Salmonella, and Shigella), seven different yeasts (including Candida albicans), and 15 different fungi (including common food-storage fungi).
In vitro studies have shown that lemongrass essential oil can be more effective than antibiotics against certain pathogenic bacteria. Lemongrass oil appears to increase the range of action of phenoxyethanol (a preservative for pharmaceuticals, cosmetics, and home care products) against E. coli, Staphylococcus aureus, and Pseudomonas aeruginosa. As antibiotic resistance becomes more common, the use of lemongrass essential oil shows promise in the control of a wide range of bacterial infections.
Citral, linalool, myrcene, and geraniol, which are present in lemongrass essential oil, have antifungal properties. In vitro studies with Candida albicans demonstrate linalool’s ability to reduce cell size and cause abnormal germination, which inhibits the ability of Candida species to replicate efficiently. Citral appears to inhibit both mycelial and yeast-form growth of C. albicans. These effects could lead to the reduction and potential inhibition of the biofilm formation necessary for Candida species to thrive.
A 0.1% concentration of lemongrass oil completely inhibited herpes simplex virus-1 replication in vitro. In a small, randomized, controlled trial, lemongrass tea was found to effectively treat oral thrush (a fungal infection of the mucous membranes of the mouth that is caused by Candida species) in patients with human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS).
- Antioxidant Properties – Lemongrass is a good source of protective antioxidant compounds such as vitamin C and flavonoids. In the food industry, there has been increased interest in natural methods of food preservation, and essential oils derived from plants can be used to inhibit microorganisms that cause food spoilage and shorten the shelf-life of food products. The strong inhibitory effects of lemongrass essential oil against a wide variety of pathogens, combined with its antioxidant potential, make it a potential food preservative.
An in vitro study demonstrated the protective effects of lemongrass against hydrogen peroxide-induced oxidative stress and liver damage. Lemongrass intake was associated with a decrease in hydrogen peroxide-induced elevation of liver enzymes and a reduction of oxidative stress-induced pathological changes. In a rat study, citral isolated from lemongrass was shown to enhance detoxification in the liver by inducing glutathione S-transferase, an enzyme involved in the detoxification process.
- Gastroprotective Properties – In another rat study, lemongrass was investigated for its gastroprotective benefits. A lemongrass extract was found to have protective effects against stomach lesions. A similar study investigated the effects of lemongrass essential oil against damage caused by ethanol and aspirin exposure. The essential oil showed a protective effect against ethanol-and aspirin-induced lesions. For people who regularly consume alcohol or use non-steroidal anti-inflammatory drugs (NSAIDs), these results suggest that lemongrass oil may help protect the lining of the stomach, which can be damaged by use of NSAIDs and alcohol.
- Anxiolytic Properties – In aromatherapy, lemongrass essential oil often is used as a mood enhancer. While some studies support lemongrass’s sedative and anxiety-reducing effects on the central nervous system, these effects have not been consistently demonstrated.
Studies on lemongrass aqueous root extract and methanolic leaf extract have demonstrated anxiolytic effects. These effects could be related to the flavonoids, alkaloids, and terpenoids present in lemongrass extracts, all of which have been associated, in other plant extracts, with reduced anxiety.
Empirical studies show that inhalation of lemongrass essential oil has an inhibitory effect on the central nervous system by increasing levels of the neurotransmitter gamma-aminobutyric acid (GABA) in the brain. This suggests that the anxiolytic effects of lemongrass essential oils may be mediated by acting upon the GABA-benzodiazepine interaction complex.
- Neuropharmacological Properties – Lemongrass water extracts (teas or broths) contain neuroprotective nutrients such as zinc, magnesium, and folate, which are associated with improved memory, concentration, and information processing. In a mouse study, lemongrass essential oil was found to be three times more effective than sodium thiopental, a common anesthetic, at prolonging sleep. Additionally, lemongrass essential oil has been shown to raise the seizure threshold and reduce convulsive episodes in rats and should be further investigated for use in managing epilepsy in humans.
- Hypoglycemic and Hyperlipidemic Properties – A rat study examined the effects of oral intake of three different doses of lemongrass tea on weight reduction, serum cholesterol levels, and fasting plasma glucose. Researchers observed a dose-dependent reduction in weight, with the higher dose leading to a greater weight reduction, and the maintenance of low blood glucose levels. Additionally, this study reported a significant, dose-dependent reduction in levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, and very low-density lipoprotein (VLDL) cholesterol, while high-density lipoprotein (HDL) cholesterol increased significantly. Levels of triglycerides were unaffected.
In a small open-label human clinical trial, effects of lemongrass tea on 31 patients with hypertension were observed. Participants were given a lemongrass infusion twice daily for 16 weeks. Lemongrass tea intake had a significant effect on reducing blood pressure, but no significant effect on heart rate or other recorded study parameters.
Medicinal Uses: * Aromatherapy * Cellulite * Culinary/Kitchen * Herbal Teas * Insect Repellent
Lemongrass Side Effects: Essential oil for external use only.
Lemongrass Drug Interactions: None Noted
