Chapter 18 - Pelargonium graveolens

Abstract

Pelargonium graveolens L’Her. (Geraniaceae), generally known as ‘rose geranium’, is an aromatic, erect plant that can reach a height of 1.3m. The young plants have soft, succulent and hairy stems that become woody as the plant ages. The rose-scented leaves have deeply indented margins. The plant’s distribution covers Mozambique, Zimbabwe, and the Limpopo and Eastern Cape provinces of South Africa. The aerial parts have been widely used in various traditional medicine systems to reduce general pain and inflammation, as well as for managing anxiety. The aromatic nature of the plant affords its various therapeutic properties that include relaxant, sedative, anxiolytic, antidepressant calming and tension-relieving effects. The plant aids to relieve premenstrual and menopausal problems, poor blood circulation, nausea, tonsilitis and gastro-intestinal disorders. Pelargonium graveolens produces a well-known commercialised essential oil, rose geranium. The global demand for rose geranium oil is high, as it a good substitute for the expensive rose oil in the fragrance industry. Pharmacological in vitro and in vivo studies of the oils and extracts of geranium have been conducted, including its anti-oxidant, antimicrobial and anti-inflammatory activities. Citronellol, geraniol, linalool, isomethone, citronellyl formate, geranyl formate and guaia-6,9-diene are marker constituents of the oils, and were identified by gas chromatography coupled to mass spectrometry (GC–MS). The presence of linalool and geraniol in the oil was also confirmed by semi- automated high-performance thin-layer chromatography (HPTLC).