<![CDATA[This research was conducted to determine effect of material:solvent ratio and extraction time with mi crowaves on ethanol extrac of robusta coffee husk as a source of antioxidant activity and to obtain the best material:solvent ratio and to extraction time wich can produce ethanol extrac of robusta coffee husk as a source of antioxidants. The experimental design used in this research was a factorial randomized block design, which are grouped into 2 groups based on the implementation time and consisted of two factors. The first factor was material:solvent ratio which consisted of 3 level that namely 1:20 ; 1:30 ; 1:40. The second factor was the time of extraction which consisted of 3 level namely 5, 10, and 15 minutes. The data were analyzed by analysis of variance and continued with Tukey test. The result showed that the material:solvent ratio and time extraction had a very significant effect on yield, total phenolic, total flavonoid, and antioxidant activity. Interaction between treatments had a very significant effect on anti-oxidant activity and total flavonoid. And had sigificant effect on total phenolic content. The solid to sol-vent ratio and extraction time did not significant effect of robusta coffee husk yield. The best treatment showed that the solid to solvent ratio 1:30 for 10 minutes using microwaves which characteristic yield was 8.86±0.08%, total phenol was 8.55±0.13 mg GAE/g extract, total flavonoid was 6.87±0.12 mg QE/g extract, and antioxidant activity was 37.84±0.14 mg GAE/g extract.]]>
