Betara's areca nuts are high quality areca nuts from Betara, Tanjung Jabung Barat, Jambi, Indonesia. Areca contains many nutrients and active compounds such as flavonoids, phenolics, catechin, quercetin, and a small percentage of tannins, beneficial for natural antioxidants. The natural antioxidants can be separated through Ultrasonic Assisted Extraction or UAE technique. The advantages of the UAE technique are that it uses low temperature, reduces solvent use, and is costeffective and quick. The ultrasonic waves in the UAE technique will accelerate the penetration of the liquid into the cell membrane wall so that the immediate release of active compounds. This study aims to determine the effect of excitation time on antioxidant activity in extracting antioxidants using the UAE method. The result showed that increasing excitation time increased the water content from 78% to 89% and increased the yield from 6.5% to 7.1%. The antioxidant activity (IC50) ranged from 4.9 to 3.5 ppm (db), suggesting that the areca nuts have a very high antioxidant activity.

A paradigm progressive encourages the community to implement a new approach in mitigation that integrates disaster prevention, edu-eco-tourism, economic recovery, early warning system, and community preparedness. Volcanic eruptions are disasters that occur due to natural changes in earth conditions or natural phenomena that cannot be avoided by their existence or occurrence. In dealing with volcanic eruption disasters, disaster mitigation measures are needed. One of the scientific efforts to mitigate the Mount Semeru disaster is to observe its dynamic activities with a scientific approach which is monitored directly. An integrated lab specially designed for observing the activity of Mount Semeru and developed area at Pronojiwo for multi purposes such as training center, edu-ecotourism center, and early warning system.