Toxicity of Ruta angustifolia (Rutaceae) Leaves Extracts Using Brine Shrimp Lethality Test (BSLT)

Ruta angustifolia L. (Rutaceae) which commonly known as “Garuda”, “Aruda” or “Inggu” grown as herb and can be found in Malaysia and Indonesia. It has been used for extensively by local people to treat fever, influenza, cough (plant decoction) and headaches (plant decoction). However, there are lacking of scientific data found on this species on its toxicity level and the bioactive components. The objective of this study was to determine the toxicity of R. angustifolia leaves extracts using BSLT. The crude ethanol extract was obtained by ultrasonication process in an ultrasonic bath. The ethanol extract later subjected to liquid-liquid partitioning to obtain various partitions; hexane, dichloromethane, ethyl acetate and butanol partitions. The lethality test was performed against brine shrimp nauplii with various concentrations of extracts; 1000, 500, 250, 125, 62.5, 31.25, 15.625 μg/ml. The toxicity activity was determined by calculating the percentage of mortality within 24 hours to obtain LC50 values which is the lethal concentration required that can kill half the population of nauplii. Dichloromethane and hexane partitions exhibited the highest toxicity level with the LC50 values of 76.00±7.99 μg/ml and 81.21±3.20 μg/ml, respectively, while
LC50 values for other partitions; ethanol is 125.84±18.21 μg/ml, ethyl acetate is 318.67±30.76 μg/ml and butanol is 3197.74±378.02 μg/ml. Potassium dichromate (the control) showed LC50 value of 27.62±3.01 μg/ml. Hence, the findings reveal that this plant is only safe to be consumed at a certain dosage only.