Evaluation of chemical composition, anti-inflammatory and anti-nociceptive effects of Eugenia caryophyllata buds essential oil

Abstract

Background & Aim:<em> Eugenia caryophyllata</em> well known as Clove is a tree from Myrtaceae family that several parts of this plant traditionally used in dental care as an analgesic. This study aimed to assess the chemical composition, anti-inflammatory and anti-nociceptive activities of the essential oil extracted from Clove buds. Experimental: The essential oil of Clove buds (EOC) was extracted by Clevenger type apparatus and its chemical composition determined by gas chromatography-mass spectrometry (GC-MS). Analgesic activities of EOC were measured by formalin-induced orofacial pain and tail immersion test in rat. Also anti-inflammatory effect of the EOC was evaluated by using xylene induced ear edema test in mice. Results: EOC (100, 200 mg/kg, SC) and ketoprofen (80 and 160 mg/kg, IP) inhibit only the second phase of orofacial pain. Morphine (5 mg/kg) as a positive control significantly (p <0.05) reduced pain response in the both phases of pain. Pre-treatment of animals with naloxone did not prevent the EOC (200 mg/kg) analgesic activity. Co-administration of sub-analgesic doses of EOC (50 mg/kg) and ketoprofen (40 mg/kg) significantly (p <0.05) reduced nociceptive behavior in second phase. Also EOC (100 and 200 mg/kg) failed to increase nociceptive response latency in the tail immersion test. Meanwhile, EOC (100 and 200 mg/kg) and ketoprofen (80 mg/kg) significantly (p <0.001) attenuated xylene-induced ear edema in mice. Also according to GC-MS results the major components of the EOC were eugenol (54.86%), β-Caryophyllene (20.19%), α-Humulene (7.11%), eugenol acetat (4.85%) and Chavibetol (2.23%). Recommended applications/industries: These data showed that EOC possessed potent anti-inflammatory activity and produced non-opioid mediated analgesia in the second phase of orofacial pain without any effect on tail immersion response.