Antioxidant activity and toxicity of Annona muricata leaves extract
Mohd Kamal N.H., Abd Rashid L., Azman M., Hafizi R., Muhammad Khair M.A.

Abstract
Annona muricata leaf is used in traditional medicine to treat many diseases and their complications. This study aimed to optimize the preparation of A. muricata water extract with a high antioxidant effect and determination of its toxicity on brine shrimp and rat. In this study, water extraction was performed at different temperature (40oC, 60oC, 80oC and 100oC) for different times (15 min, 30 min, 1 h, 2 h, and 3 h). Antioxidant in-vitro tests such as DPPH, FRAP and TPC were used for the optimization of extract. The results showed that the best parameter for A. muricata extract preparation was 100oC/30 min. The extract was again prepared by using the parameter of 100oC/30 min based on the antioxidant test. The brine shrimp lethality test (BSLT) and single-dose acute toxicity test on rat were carried out to study its toxicity. Based on BSLT results, the LC50 (median lethal concentration) values were not detected. Besides that, all rats that were given A. muricata extract were not died after 14 days of treatment. In a conclusion, the results showed that the optimized A. muricata extract might be not toxic.

Keywords: Annona muricata, water extract, antioxidant, phenolic compound, brine shrimp lethality test, acute 
toxicity test