Batang kelapa sawit mengandung kadar pati yang tinggi sehingga memiliki potensi digunakan sebagai bahan baku bioplastik. Kadar amilosa dalam pati batang kelapa sawit dapat dinaikkan melalui proses modifikasi dengan pelarut asetat. Tujuan dari penelitian ini adalah untuk meningkatkan sifat kimia (kadar amilosa) dan termal pati batang kelapa sawit melalui proses modifikasi sebagai bahan baku bioplastik. Dalam penelitian ini, pati batang kelapa sawit diperoleh melalui proses ekstraksi. Modifikasi pati batang kelapa sawit dilakukan dengan menggunakan larutan asetat (CH3COOH+CH3COONa) pH 7. Karakterisasi pati batang sawit dilakukan dengan melihat komposisi kimia (kadar air, abu, protein, lemak, amilosa, dan amilopektin), analisis gugus , dan karakteristik termal. Hasil karakterisasi komposisi kimia pati batang kelapa sawit termodifikasi menunjukkan peningkatan kadar amilosa dari 26% menjadi 29%. Kandungan rantai lurus dalam amilosa yang semakin banyak akan meningkatkan kestabilan pati. Hasil Thermal Gravimetry Analysis (TGA) menunjukkan bahwa pati batang kelapa sawit termodifikasi lebih cepat terdegradasi dibandingkan pati batang kelapa sawit tidak termodifikasi/alami, sedangkan data Derivative Thermal Gravimetry (DTG) dan analisis Differential Scanning Calorimetry (DSC) menunjukkan pengurangan massa pati batang kelapa sawit termodifikasi lebih kecil dari pati batang kelapa sawit tidak termodifikasi/alami serta pati batang kelapa sawit termodifikasi mempunyai Tg (Gelatinization Temperature) yang lebih rendah. Hasil penelitian pati batang kelapa sawit termodifikasi ini diharapkan dapat diaplikasikan sebagai bahan baku bioplastik yang ramah lingkungan.

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Petroleum-based plastic causes a threat to the environment at the end of its use because it cannot decompose naturally. Therefore it is necessary to develop bioplastic for food packaging but has the same function as conventional plastic. Starch based bioplastic, generally made from cassava starch. The disadvantage of this bioplastic is its low mechanical strength and damage if exposed to water. One way to increase the mechanical strength of bioplastic is to add fiber. Oil palm trunks are the source of natural fiber that is available in considerable amounts. The purpose of this study was to find out the characteristics of bioplastic from cassava starch with the addition of oil palm trunk fiber, in various amount. Bioplastics are made by heating a solution of cassava starch (tapioca: distilled water = 1:20) at 70 °C for 1 hour while stirring. After starch solution was gelatinized, glycerol (0.3%) and citric acid (1%) was added, and stirring was continued for 15 minutes. Oil palm fiber from oil palm trunk is added to the solution of cassava starch as much as 0%, 1%, 3% and 5% of the weight of cassava starch. The bioplastic solution is then poured into a (20x20) cm acrylic sheet with a thickness of ± 5mm. Furthermore, it is cooled at room temperature for 3 days so that the bioplastic sheet is ready for mechanical strength testing based on ASTM D 882-75b Tensile Properties of Thin Plastic Sheeting, and for thermal properties testing with Thermo Gravimetry Analyzer. The addition oil palm trunk (OPT) cellulose fibers into bioplastic made from modified cassava starch, produce bioplastic with higher tensile strength compare to modified cassava starch bioplastic with addition of OPT pulp fibers. The decomposition temperature of bioplastic made from modified cassava starch with 1% OPT cellulose was higher than of bioplastic with 1% OPT pulp, indicates that bioplastic with 1% OPT cellulose fibers have better thermal stability compare to bioplastic with 1% OPT pulp fibers

Sonokeling (Dalbergia latifolia Roxb) stands are widely lost throughout the world. Sonokeling is currently classified as an Appendix II CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) wood. Therefore, a study on the existence and characteristics of Sonokeling were expected to contribute in providing population data and basic properties of the wood. Exploration was conducted in Plot No. 25, KPH (Forest Management Unit) Gundih, Perum Perhutani Cepu, Central Java. Sonokeling stands have been planted since 1975 (more than 40 years-old) in an area of 54.20 ha, which was not productive for Teak and mixed with Mahogany. Sample was taken from upper part of stem with around 30 cm in diameter and 30 cm in length. The sample was further cutted into 2 x 2 x 2 cm for physical, 30 x 2 x 2 cm for Modulus of Elasticity (MOE) and Modulus of Rupture (MOR), and 4 x 2 x 2 cm for Compression Strength Parallel to the Grain (CSPG) tests. The results showed that specific gravity of sapwood dan heartwood were 0.79 and 0.82, respectively. The average values of MOE, MOR, and CSPG were 117,722, 1122.19, and 1022.93 kgf/cm2, respectively. Therefore, Sonokeling can be classified into Strength Class II.

Sweet sorghum bagasse (SSB) obtained after juice extraction is a potential feedstock for fermentable sugars production that can be further fermented to different kinds of products, such as ethanol or lactic acid. The proper particle size resulted from phsyical pretreatment and different pretreatment processes including water, alkali, hydrothermal, and alkali hydrothermal for improving enzyme susceptibility of SSB have been investigated. After grinding to particle sizes of <250 μm, 250-420 μm, and, > 420 μm the sweet sorghum bagasse was washed to eliminate residual soluble sugars present in the bagasse. Dosages of cellulase enzyme used in saccharification were 60 and 100 FPU/g substrate, respectively. The results showed that SSB with particle sizes of 250-420 μm had the highest cellulose (38.33%) and hemicellulose content (31.80%). Although the yield of reducing sugar of 250-420 μm size particles was lower than that of smaller particle (<250 μm), the former was more economical in the energy consumption for milling process. The yields of reducing sugar obtained from enzymatic hydrolysis of alkali hydrothermal pretreated sweet sorghum bagasse were 1.5 and 0.5 times higher than that from untreated sweet sorghum bagasse at enzyme loading of 100 and 60 FPU/g substrate, respectively. Furthermore, alkali hydrothermal pretreatment was able to remove as much as 85% of lignin. Morphological analysis using SEM (Scanning Electron Microscope) showed that samples treated with alkali hydrothermal have more pores and distorted bundles than that of untreated sweet sorghum bagasse. Meanwhile, XRD (Xray diffraction) analysis showed that pretreated samples had a higher crystallinity and smaller crystallite size than untreated sweet sorghum bagasse, which might be due to removal of amorphous lignin components.