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Oil palm empty fruit bunches (OPEFB) have not been properly utilized by most palm oil mills and communities in Indonesia. The processing and utilization of OPEFB by palm oil mills are still limited. Due to high cellulose contents, it potentially made into various bioproducts, especially as biomaterials. Therefore, a proper extraction technology is needed to obtain a high level of cellulose purity because alkaline treatment can solely remove a part of hemicellulose and lignin. A higher cellulose content can be obtained by further chemical treatments through the bleaching process. However, no information regarding the difference of the isolation performance method to produce cellulose purity by delignification first or vice versa bleaching as an initial stage. The research determined the purity of EFB cellulose with differences in the sequence of bleaching and alkaline delignification stages. The three methods were carried, namely the first method by bleaching using sodium chlorite 3% two times, followed by delignification of NaOH 10% at room temperature, second method with the same conditions but delignification of NaOH 10% at a temperature of 70-80°C and third method by delignification and continued bleaching under the same conditions. The results showed the bleaching method of sodium chlorite of 2 cycles and continued by alkaline delignification (NaOH 10%) at room temperature resulted in higher cellulose purity than other methods. The FTIR test results indicated the detection of the C-O functional group at a wavelength of 1196 cm-1 and the C-H functional group at a wavelength of 2967 cm-1.

Background and Objective: Kalanchoe tomentosa is identified and their different characteristics regarding the antibacterial and antioxidant properties have a vast effect. Fresh K. tomentosa leaves obtained from Bandung, Indonesia was extracted using n-hexane followed by serial dichloromethane maceration. Materials and Methods: N-hexane and ethyl acetate were used to separate the dichloromethane extract using vacuum liquid chromatography and the isolated compounds were recrystallized with n-hexane. Results: About 37 mg of dichloromethane extract was obtained from the extraction process. Recrystallized compound isolates were identified as stigmast-5-en-3-ol or $-sitosterol. Both dichloromethane extract and $-sitosterol isolated compounds showed strong bacteriostatic activity against S. aureus with MIC = 15.63 and 7.81 µg mLG 1 and K. pneumonia with MIC = 7.81 and 31.25 µg mLG 1 , respectively. However, only dichloromethane extract exhibited a bactericidal effect (7.81 µg mLG 1 ). Conclusion: The pure $-sitosterol compound was isolated from K. tomentosa dichloromethane extract. Both the dichloromethane extract and the isolated $-sitosterol compound had antibacterial effects against S. aureus and K. pneumonia.