In Vitro Immunomodulatory Activity of Calamansi Orange Peel (Citrus microcarpa Bunge) Essential Oil on Mice Lymphocyte Cell Proliferation

Abstract

Immunomodulators remain the most crucial part of the prevention and even treatment process for various diseases related to the body’s immune system. Calamansi orange peel is a waste from the calamansi syrup industry which is widely available in Bengkulu. This can be used to extract the essential oil from the peel of calamansi orange which is known to have high antioxidant activity. The purpose of this study was to determine the potential immunomodulatory activity of calamansi orange peel essential oil on mouse lymphocyte cell proliferation in vitro. The essential oil was obtained by steam-water distillation method. immunomodulator test was carried out by taking essential oils with varying concentrations, namely 6.25- 12.5- 25- 50- and 100 g/mL. Isolated lymphocyte cells were obtained from the spleen of Swiss Webstern strain mice. Lymphocyte cell proliferation test was performed using MTT Assay and absorbance was measured using an ELISA reader at 550 nm. In this study, the essential oil yield was 2.13%. The results of the immunomodulator activity test analysis showed that the essential oil of calamansi orange peel has potential immunomodulatory activity against lymphocyte cell proliferation. The highest immunomodulatory activity was obtained at an essential oil concentration of 50 g/mL with an optical density (OD) value of 0.348.