Summary: | Brassicaceae plant is a commodity of edible plant that is very important for Indonesia, with cabbage worm (Plutella xylostella) as its main pest. Pest control with biopesticide is needed to preserve environment and increase crops production. Several biological substance is toxic to cabbage worm, including bromelain enzyme and isothiocyanates. Extraction of bromelain is experimented by varying mixing duration (15, 30, 45, 60 mins) and solvent type (distilled water and phosphate buffer). Extraction of isothiocyanate is experimented by varying the solvent ratio (1:1, 1:2, 1:3), using dichloromethane as solvent. For the broccoli stem sample, phosphate buffer is added to maintain pH. Enzyme activity test is used with product tyrosin concentration as standard. Isothiocyanate is determined with GC-MS analysis. The most effective extraction method for bromelain is with distilled water as solvent with 15 min mixing time. The most effective extraction method for isothiocyanate is with 1:1 solvent ratio at 37°C temperature without adding phosphate buffer. Efficacy of each sample to cabbage worm is also experimented by feeding it broccoli leaf spread with sample and observing the mortality rate. Bromelain and isothiocyanate proved to be toxic to cabbage worm and can be used as alternative bioinsecticide with the highest mortality of cabbage worm is by isothiocyanate from radish peel, reaching 100%.
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