Yield, Antioxidant Activity, and Toxicity of Ethanol Extracts from Air- and Sun-Dried Sikkam Leaves (Bischofia javanica Blume) Obtained by Maceration and Soxhlet Extraction

Abstract

Sikkam (Bischofia javanica Blume) is a species of the genus Bischofia in the Euphorbiaceae family that can be used as a traditional medicine. This study aimed to determine the yield, antioxidant activity, and toxicity of sikkam leaf extract. Sikkam leaves were dried at room temperature (air-dried) and under direct sunlight (sun-dried). The extracts were obtained using the maceration and Soxhlet extraction methods with 96% ethanol as the solvent. The yields of air-dried (A-D) and sun-dried (S-D) sikkam leaf extracts isolated by maceration and Soxhlet extraction differed significantly (p<0.05), with average values of 20.48±2.30, 22.32±1.19, 24.31±2.01 and 24.71±0.09% for A-D maceration, S-D maceration, A-D Soxhlet extraction, and S-D Soxhlet extraction, respectively. The antioxidant activity (IC₅₀) of sikkam leaf extracts, tested using the DPPH method, showed significantly different mean values (p<0.05), with the following averages: 11.13±1.30, 12.86±2.88, 11.36±1.47, and 14.82±1.19 µg/mL for A-D maceration, S-D maceration, A-D Soxhlet extraction and S-D Soxhlet extraction, respectively. The ethanol extracts of air-dried and sun-dried sikkam leaves isolated via maceration and Soxhlet extraction fall into the category of very strong antioxidant activity. The toxicity (LC₅₀) of the sikkam leaf extracts tested using the Brine Shrimp Lethality Test (BSLT) differed significantly (p<0.05), namely 941±37, 914±67, 985±72 and 700±39 µg/mL for A-D maceration, S-D maceration, A-D Soxhlet extraction and S-D Soxhlet extraction, respectively. Ethanol extracts of air-dried and sun-dried sikkam leaves, isolated by maceration and Soxhlet extraction, are classified as non-toxic.