 Gen info
- Pelargonium graveolens, known as rose geranium, is one of more than 250 species in the genus Pelargonium, belonging to the Geraniaceae family.
- Etymology: The genus name Pelargonium derives from Greek pelargos, meaning "stork", referring to the shape of the geranium flower, which resembles a stork's beak.
The species epithet graveolens refers to the strong-smelling leaves.
Botany
• Malvarosa is a small branching hairy shrub growing about a meter high. Leaves are
long-petioled, palmately compound, 5- to 7-lobed or parted and fragrantly
mint-scented. Flowers are many, pink or light purple on long peduncles. Calyx is hairy and almost sessile.
• Pelargonium graveolens is a shrub up to 1.3 m tall. Foliage: Deeply incised leaves are covered in soft, glandular hairs that produce rose-scented oils. Flowers: White to pink flowers are produced in rounded clusters that look like umbel inflorescences. Fruit: Fruits are shaped like the long beak of a stork. (36)
 Distribution
- Cultivated, not naturalized.
- Cultivated for its aromatic and ornamental foliage and for its medicinal value.
- Native to South Africa.
Constituents
• Essential oil
contains myrcene, or beta-myrcene, an olefinic monoterpene, used
in traditional and commercial repellent preparations.
• Yields citronellol, linalool, isomenthone, geraniol (widely used in the pharmaceutical industry) and citronellyl formate.
• Study of essential oil of P. graveolens yielded
24 compounds; major constituents were: ß-citronellol 36.4%, citronellyl formate 12.1%, geraniol 10.7%, isomenthone 7.3%, linalool 5.1%, ß-caryophyllene 3.4%, cis-rose oxide 2.8%, para-menthone 2.7%, geranyl formate 2.6%, geranyl n-butyrate 1.3%, germacrene D 1.3%. (16)
• Study of geranium essential oil from Tajikistan yielded 79 components representing 95.1% of total oil identified. Main constituents were: citronellol (37.5%), geraniol (6.0%), caryophyllene oxide (3.7%), menthone (3.1%), linalool (3.0%), β-bourbonene (2.7%), iso-menthone (2.1%) and geranyl formate (2.0%). (17)
- Study of aerial parts for essential oil yielded
major constituents of citronellol (28.90%), trans-geraniol (18.03%), 10-epi-y-eudesmol (8.27%). isomenthone (5.44%), linalool (5.13%), geranyl acetate (4.52%), γ-cadinene (2.89%), geranyl butyrate (2.53%), geranyltiglate (2.50%), and gemacrene D (2.05%) as major constituents. (24)
- GC-MS analysis yielded 70 chemicals, with oxygenated terpenoids the most abundant group. Citronellol (24.44%), citronelly formate (15.63%), γ-eudesmol (7.60%), and iso-menthone (7.66%) were the dominant chemical markers. (see study below) (25)
Properties
• Astringent and hemostatic.
• Considered anti-inflammatory, antiseptic, astringent, sedative, anti-cancer, antioxidant, antibacterial.
- Studies have suggested antioxidant, antibacterial, antibiotic synergism
, hypoglycemic, hypolipidemic, antifungal, spermatogenesis, wound healing, antinociceptive, anticancer, α-glucosidase inhibitory, anti-dermatophytic, anti-inflammatory properties.
Parts used
Leaves, flowers, essential oil.
Uses
Edibility / Culinary
- Flowers and leaves are edible; usually added to salads.
- Fresh leaves as condiment or tea.
- Rose-scented leaves used as flavoring in desserts, jellies, vinegars.
Folkloric
- Used in various traditional medical systems for treatment of hemorrhoids, dysentery, inflammation, and cancer.
-
Decoction of leaves used for cough and stomach aches.
- Herbal tea from leaves used to reduce anxiety, inflammation, and body pains.
- Elsewhere used to stop bleeding, for wound healing and for antibacterial properties.
- Used for rheumatism, colitis, hepatopancreatic afflictions.
- Used as emmenagogue.
- In Tunisia, used in the treatment of hyperglycemia.
Aromatherapy
- Leaf essential oil used in aromatherapy and massage for stress and skin problems. Essential oil considered to have antidepressant properties but has not been proven by clinical studies.
Others
- Ornamental: Planted as ornamental plant for beauty and fragrant aroma.
Cultivars impart a wide variety of scents.
- Scent: Used in perfumery, cosmetics, and aromatherapy.
Leaves used in potpourri for perfuming rooms.
- Cosmetic: Popular ingredient in cosmetic products for acne, anti-wrinkling, anti-stretch marks preparations.
- Repellent: The oil is used to repel mosquitoes, head lice and other creepers.
Studies
• Essential Oils / Antioxidant: Study of essential oil and monomer as well as residue and waste water after distillation from buds, stems, and leaves of Pelargonium graveolens showed antioxidant effect using DPPH assay. (1)
• Antibacterial Effect / Antibiotic Synergism: Study was done to verify the possible synergistic effect between P graveolens essential oil and the antibiotic Norfloxacin. The results showed the occurrence of pronounced synergism between P graveolens essential oil and Norfloxacin against three bacterial species. (3)
• Effect of High Dose on the Liver and Kidney: Study evaluated the effect of a high dose of plant extract on two vital organs i.e. liver and kidney. Animals were given geranium extract 869 mg/kg/day orally for 20 days. Biochemical analysis showed significantly increased AST, ALT, GGT, LDH, urea, creatinine, total lipid and cholesterol after treatment and 10-day recovery period. Glucose, total protein and albumin and globulin were significantly decreased after the treatment period. Histological exam of liver showed evidence of degeneration, necrosis, and mononuclear infiltration; kidney sections showed tubular degeneration and glomerular atrophy post-treatment and degenerative changes in proximal and medullary tubules at recovery periods. Some changes disappeared after 20-day recovery period. Study suggests over dose of geranium extract cause liver and kidney damage. The plant should be used caution in dosing for clinical therapy, and suggests periodic testing of liver and kidney functions for long term use or therapy (4)
• Essential Oil / Antibacterial: Study analyzed essential oils of Pelargonium graveolens and Vitus agnus-castus for antibacterial activity. ß-citronellol is a prominent component of P. graveolens volatile oil. The essential oils yielded similar compounds: α-terpineol, citronellyl acetate, ß-caryophyllene, α-humulene and caryophyllene oxide. The essential oils were active against all of the studied bacteria except Listeria monocytogenes. (6)
• Denture Stomatitis / Essential Oil: In a double-blind randomized clinical trial, the application of a 1% Geranium oil topical gel formulation showed to be more effective than placebo in the treatment of denture stomatitis. (7)
• Hypoglycemic / Leaf Essential Oil: Study evaluated leaf essential oil for hypoglycemic and antioxidative properties. Results showed a hypoglycemic effect significantly more effective than that of glibenclamide, and suggests the essential oil may be helpful in the prevention of diabetic complications. (8)
• Antibacterial Against Staph Aureus Stains / Oil: Study evaluated the antibacterial properties of geranium oil from P. graveolens against one standard S. aureus ATCC 433000 strain and 70 clinical S. aureus strains. Results showed P. graveolens has strong activity against all clinical S. aureus isolates, including multidrug resistant strains. (9)
• Hypoglycemic / Hypolipidemic / Essential Oil: Study evaluated essential oil and aqueous leaf extract of P. graveolens against pancreatic triacylglycerol lipase, α-amylase and α-glucosidase. Comparable to acarbose, PG leaves aqueous extracts (AEs) were identified as in vitro potent and efficacious dual inhibitors of α-amylase and α-glucosidase with IC50: 4.6±0.1 mg/mL (p<0.001, n=3). Results suggest the leaves, as nutraceutical modulating gastrointestinal carbohydrate and lipid digestion and absorption, maybe advocated for obesity/diabetes/metabolic syndrome management. (10)
• Benefits of Male Reproductive System / Hypolipidemic / Essential Oil: Study showed a positive influence of geranium essential oil in animal male reproductive system through by prevention of testicular oxidative damage induced by delmathrin in mice with improved total sperm motility, viability and morphology in mice spermatozoa. (11)
• Benefits of Nanosilver Application on Photosynthetic Pigments: Study evaluated the potential effects of nanosilver application on variations of photosynthetic pigments (chlorophyll and carotenoids) and essential oil content and composition of P. graveolens. Results showed nanosilver application can maintain and enhance the photosynthetic pigments and essential oil content of P. graveolens. (12)
• Antifungal / Pityriasis Versicolor: Study showed Z. multiflora, P. graveolens and C. cyminum essential oils have considerable anti-Malassezia activities, suggesting further studies for clinical applications for the treatment of pityriasis versicolor. (13)
• Potentiation of Antimicrobial Activity of Ciprofloxacin / Essential Oil: Study evaluated the antimicrobial effect of P. graveolens essential oil in combination with ciprofloxacin on uropathogens, viz., K. pneumoniae, P. mirabilis, and S. aureus. Results showed synergism of PG essential oil with ciprofloxacin which may be applied for the treatment of urinary tract infections. (14)
• Antioxidant / Antibacterial / Antifungal: Study on in-vitro antioxidant activity showed IC50 of 14.49 ± 0.46 µg ml; antibacterial activity MIC of 2000 µg ml; and antifungal activity MIC 3330 of µg ml. (15)
• Antibacterial / Essential Oil: Study of essential oil for antibacterial activity showed growth inhibition against E. coli, P. aeruginosa, S. aureus, B. subtilis, and S. enteritidis. The most sensitive strain was Staphylococcus aureus, (see constituents above) (16)
• Inhibition of Proteus mirabilis / Essential Oil: Study evaluated the anti-swarming potential of P. graveolens essential oil against Proteus isolate. Results showed inhibition of swarming by P. graveolens EO and suggests a potential as a product for preventing P. mirabilis infections. (18)
• Protective Effect against Lead Acetate on Spermatogenesis / Leaves: Study investigated the protective effect of P. graveolens leaf extract on spermatogenesis process in male rats treated by lead. Results showed the PG extract inhibited the detrimental effects of lead acetate on rat testes. PGE increased testosterone hormone and number of sperms in the treated rats. (19)
• Wound Management: Study of ethanolic extract formulation showed strong activity against clinical pathogens such as E. coli and P. aeruginosa. Results reveal that ethanolic extract of P. graveolens may be a suitable drug to develop into nanofilm as wound dressing material for advanced wound management. (20)
• Antinociceptive / Leaves: Study of PG extract of leaves showed antinociceptive effects in male mice using Tail Flick and Writhing models of testing. The analgesic effect may be related to its flavonoid composition and its effect on the opioid system. (21)
• Activity Against House Dust Mites / Leaves: Study evaluated the mite-control activities of materials obtained from P. graveolens oil against Dermatophagoides farinae and D. pteronyssinus compared to commercial benzyl benzoate and DEET. Results showed the mites were controlled more effectively by application of geraniol and ß-citronellol. Results suggest their potential in the management of populations of D. farinae and D. pteronyssinus owing to their selective actions and safety for mammals. (22)
• Silver Nanoparticles / Antibacterial: Study reports on a simple, low cost, clean, nontoxic, and rapid approach for bioreduction and synthesis of silver nanoparticles from P. graveolens leaf extract. The nanoparticles showed antibacterial activity against P. aeruginosa, P. mirabilis, E. coli, S. flexneri, S. somenesis and K. pneumonia. (23)
• Effect on Chemical Markers / Antimicrobial / α-Glucosidase Inhibitory / Cytotoxicity / Essential Oil of Dried Leaves: Study evaluated the chemical markers, cytotoxic, antioxidant, antimicrobial, metabolic, and cyclooxygenase (COX) enzymes inhibitory characteristics of P. graveolens dried leaves essential oil from Palestine. GC-MS analysis yielded 70 chemicals, with oxygenated terpenoids the most abundant group. Citronellol (24.44%), citronelly formate (15.63%), γ-eudesmol (7.60%), and iso-menthone (7.66%) were the dominant chemical markers. The EO exhibited strong antioxidant activity (IC50 3.88 µg/mL) and weak lipase and
α-amylase suppressant effects. It exhibited high
α-glucosidase inhibitory activity compared with Acarbose with IC50s of 52.44 and 37.15 µg/mL, respectively.
The EO also significantly repressed growth of methicillin-resistant S. aureus (MRSA), more than ampicillin and ciprofloxacin, and strongly inhibited Candida albicans compared to fluconazole. Cytotoxic effect was highest against MCF-7, followed by Heb3B and HeLa cancer cells, with IC50s of 32.71, 40.71, and 315.19 µg/mL, respectively. The EO also showed selective inhibitory activity against COX-1 (IC50 275.97 µg/mL). (25)
• Essential Oil Biological Activities at Three Different Phenological Stages: Study evaluated the volatile compounds and biologic activities of aerial parts at three developmental stages. Main constituents were menthol, menthene, eremophilene, isoborneol, isogeraniol, α-pinene, linalyl acetate, and 3-carene, with quantitative differences at the three phenological stages.
Essential oil at flowering stage showed best antioxidant activity. The EO also exhibited significant effects against α-amylase, α-glucosidase, lipase, 5-lipoxygenase, and tyrosinase. EO extracted at full flowering stage showed best antibacterial effect with inhibition zones ranging from 11mm to17.30mm and MIC values from 0.25% to 2% v/v. Results suggest the full flowering stage as the best optimal harvest time for food and pharmaceutical applications. (26)
• Anti-Dermatophyte Activity / Essential Oil: Study evaluated the anti-dermatophyte effects of nine P. graveolens essential oils against Microsporum canis, M. gypseum, Trichophyton rubrum, T. mentagrophytes, and T. schoenleinii by mycelium growth percentage inhibition and micro-broth dilution assays. Highest growth inhibition percent and lowest MIC values of EO against dermatophytes were for E20 with 90% geraniol content, followed by E4 and E14 with highest amounts of geraniol (21%) and citronellol (30-35%). Results suggest use of P. graveolens EOs with high geraniol and citronellol is recommended for dermatophytes. The efficacy of EO in animal model studies should be confirmed in human studies. (27)
• Water-Soluble Polysaccharide / Antioxidant: A decoction of P. graveolens yielded an antioxidant-rich extract and water-soluble polysaccharide. Study evaluated the
effects of parameters (extraction time and temperature) on the antioxidant activity of the decoction and extraction yield of crude P. graveolens polysaccharide (CPGP). The antioxidant-rich decoction yielded about 19.76 mg RE/g DM of flavonoids and 5.31 mg CE/g DM of condensed tannins. The CPGP contained 87.27% sugar. Results suggest the rheological characteristics of CPGP
are suitable for applications industries, especially food. (28)
• Anti-Inflammatory / Essential Oil: Study evaluated the anti-inflammatory activities of essential oil of rose geranium (RGEO).
GC-MS study showed major components of citronellol (29.13%), geraniol (12.62%), and citronellyl formate (8.06%). In carrageenan-induced paw edema, the RGEO at 100 mg/kg was able to significantly reduce paw edema with comparable effect to diclofenac. The RGEO showed potent effect by topical treatment in croton oil-induced ear edema. At 5 or 10 µl of RGEO per ear, there was 73% and 88% reduction of inflammation, respectively. Histological exam confirmed RGEO inhibition of inflammatory response in the skin. (29)
• Wound Healing in Diabetic Food Ulcer Model / Essential Oil: Study evaluated the efficacy of herbal cream containing Pelargonium graveolens and Oliveria decombens essential oils topically applied for treatment of diabetic foot ulcers (DFUs) in STZ-induced diabetic rats. The herbal formulations reduced the size of the wounds in rats with DFUs. The cream containing combined herbals of PG and OD essential oils showed highest tissue repair in DFU rat models. (30)
• Effect on Inflammatory Bowel Disease / Essential Oil: Study evaluated the preventive effect of P. graveolens essential oil product (Deproherb®) in controlling induced inflammatory bowel disease (IBD) in rats. IBD was induced by acetic acid in animals pretreated with Deproherb® 100, 200, and 400 mg/kg p.o. for 5 days. All doses of Deproherb® and sulfasalazine-treated groups showed significant lower score values of macroscopic and microscopic characters compared to acetic acid-treated group. Deproheb® inhibited acetic acid toxic reactions in the rat bowel.
Results suggest anti-inflammatory potential of Deproherb® Oral drop in the experimentally induced colitis. (31)
• Effect on Glucose Metabolism / Leaves: Study evaluated the antihyperglycemic activity of aqueous extract of leaves of P. graveolens (PGLAE).
Single and repeated oral doses of PGLAE
40 mg/kg caused significant reduction in blood glucose levels of normal and diabetic rats. In acute toxicity study, all treated animals survived with no apparent adverse effects. The oral LD50 of PGLAE was greater than 2000 mg/kbw. PGLAE also improved the histological structure of the liver and potential antioxidant effect in vitro. (32)
• Antitumor / Antioxidant / Leaves: Study evaluated the the antioxidant and anti-tumor properties of P. graveolens leaves. The methanol extracts reduced the concentration of DPPH radicals in a dose-dependent manner with IC50 up to 484 µg/mL. The methanol extract showed highest antitumor activity with reduction in cell viability against MCF-7 in a dose-dependent manner with IC50 of 288 µg/mL. The ME dose-dependently inhibited cell growth of MCF-7 cells with maximum inhibition of 53.92% at 200 µg/mL. (33)
• Effects of Inhalation of Essential Oil on the Autonomic Nervous System / Linalool: Autonomic nervous system disorders have many causes for which no effective remedy has been established. Study in mice evaluated the effects of inhalation of geranium essential oil on the autonomic nervous system.
Inhalation did not affect the heart rate but made the activity of the parasympathetic nervous system dominant. The effect was attributed to linalool, a component of the essential oil, which has anti-depressant like effects in the central nervous system and vasodilatory effects in the periphery. As a mechanism of action, study suggests inhalation of essential oil may have cause the linalool to migrate into the brain via the blood and affect the autonomic nervous system. (34)
Availability
- Cultivated for aromatic
medicinal and ornamental uses. |
