Chemical Composition, Analgesic and Anti-Inflammatory Activity of Pelargonium peltatum Essential Oils from Eastern Cape, South Africa

Abstract

Pelargonium species are native to South Africa, and they have a long history in medicinal use. This study aimed to extract essential oils from different parts of P. peltatum, determine the chemical composition of the essential oils, and assess the essential oils’ biological potential as analgesic and anti-inflammatory agents. The essential oils were obtained by hydro-distilling different parts of P. peltatum, and the essential profile was determined by GC-FID and GC-MS. The analgesic activity of the essential oil was determined by using a tail immersion in hot water method in rats, whereas the anti-inflammatory activity of the essential oils was assessed according to right hind paw oedema induced by egg albumin; the three doses selected for each experiment were 100, 200, and 400 mg/kg. According to the GC-FID and GC-MS analysis, camphene (3.6–33.4%), α-terpineol (4.8–19.1%), α-thujone (1.5–15.6%), piperitone (0.9–12.2%), linalool (1.6–11.7%), myrcene (5.2–10.7%), germacrene D (3.7–10.4%), β-caryophyllene (1.2–9.5%), β-cadinene (3.4–6.7%), and β-bourbonene (4.2–6.2%) were some of the major compounds identified in the oil. P. peltatum essential oils demonstrated analgesic activity by increasing pain latency in hot water; furthermore, in an inflammation test, the essential oil reduced the egg-albumin-induced paw oedema in both the first and second phases. Therefore, the current findings suggest that P. peltatum essential oils have analgesic and anti-inflammatory properties.