Immunomodulatory and Acute Toxicity Tests of Rhizome Ethanol Extract of Etlingera Flexuosa Poulsen (Zingiberaceae) on Male Mice (Mus Musculus)

Abstract

Introduction: Immunomodulators are molecules of synthetic or biological origin that help to regulate the immune system. Many studies have focuses on exploring for phytochemical compounds that used as immunomodulatory properties in Indonesia, as well as in Sulawesi. The immunomodulatory activity of rhizome extract of E. flexuosa, an endemic flowering plant of Sulawesi on male mice were studied. Methods: 25 male mice (Mus musculus) used were randomly divided into 5 groups and Staphylococcus aureus (ATCC 25923) was used as inducer. The negative control group was given 0.5% Na-CMC (Carboxymethyl Cellulosa Sodium), positive control group was given stimuno® and treatment groups were an ethanol extract of E. flexuosa with successive doses of 200, 400 and 800 mg/kg body weight (BW) respectively. Each group was given the preparation orally for 7 days and on the 8th day the test animals were induced by Staphylococcus aureus bacteria intraperitoneally. The mice were dissected and the peritoneal fluid was taken to determine the activity of the macrophage cells. Meanwhile, Thomson and Weil method was used to study the acute toxicity test and determine the lethal dose 50 (LD50). Results: The percentage of macrophage activity in each group of negative control, positive control, extract doses of 200, 400 and 800 mg/kg BW respectively were 40.40%, 82.65%, 53.05%, 69.38% and 82.06%. Based on the results obtained, it was shown that the E. flexuosa rhizome extract has an optimum dose of 800 mg/kg BW, which was not significantly different from the positive control. Meanwhile, the symptoms of toxicity began to appear from a dose of 600 mg/kg BW to a dose of 2400 mg/kg BW including decreased motor activity, tremor, ataxia, lids and writhing. LD50 expressed in LD50 within the criteria of being practically nontoxic. Conclusions: The E. flexuosa rhizome ethanolic extract showed the immunomodulatory activity at optimum dose of 800 mg/kg BW by the increasing of macrophage phagocytosis activity. Moreover, the extract was also practically non-toxic based on LD50 value. Key words: Etlingera flexuosa, Phagocytosis, Macrophages, Immunomodulators, Immunostimulants, Lethal Dose 50, Toxicity.