Judul: Pengaruh gelombang mikro pada hidrolisis asam empulur sagu untuk produksi bioetanol
Abstrak: Sago starch, has a cheap price, a lower quality. Some problems associated with low quality of sago starch including low degrees of whiteness, starch particle size is not uniform, and the declining in starch content during the extraction process in rural areas. Color change of starch during the extraction process is a factor that causes decreasing of starch quality. When the trunk is cut and shredded, browning reaction occurs and strongly bound to the starch granule. Sago starch, isolated from the stem of sago palm, a white granule, is tasteless and odorless. Starch granules are not soluble in cold water. In the extraction, sago pith used must be fresh and must be directly processed. If it delayed would cause starch reduced in the degree of whiteness. Some starch importing countries were unsatisfied with the variety of quality of sago starch, which mostly have very low quality. This causes limited application of sago in the industry. One way to overcome the low quality of sago is to utilize for the production of glucose syrup, which does not depend on the nature of native sago starch.
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Judul: Pengaruh pemanasan gelombang mikro dua tahap pada hidrolisis asam empulur sagu untuk produksi bioetanol
Abstrak: Sago is a genus of palm that can be utilized to produce fermentable sugars as substrate for bioethanol. Sago pith is a heterogeneous substrate consists of starch and fiber. Acid hydrolysis by microwave heating radiation can break down starch and fibers together in a very short time, so it is considered to be very efficient. The use of microwave energy (as power level) and variation of heating time can produce fermentable sugar with certain characteristics. This study included the preparation of sago pith flour, pith composition analysis including proximate components, starch, and fiber components, the process of acid hydrolysis (0.3 M and 0.5 M sulphuric acid) with two steps microwave heating (power level 30% with time variation 1 minute, 2 minutes and 3 minutes the next step followed by power level 70% for 3 minutes), and characterization of fermentable sugar. As comparison, conventional treatment carried out using the autoclave on 121oC for 15 minutes. The highest sugar (105.7 g/l) contents of fermentable sugar is produced from microwave heating with power level 30% for 2 minutes followed by the power level 70% for 3 minutes. This hydrolyzate then used as substrate fermentation for Issatchenkia orientalis with different acidity (pH 3, 4 and 5), but highest ethanol produced from substrate with pH 5. Ethanol produced is still low (2.8 g/l) compared with autoclave treatment (14.5 g/). Not all sugar were consumed and it is proved that Issatchenkia orientalis only consumed glucose for growth and ethanol production.
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Judul: Posisi Filogenetik Kura-Kura Carettochelys Insculpta  (Reptillia: Testudinata)
Abstrak: Carettochelys insculpta is an endemic freshwater turtle of southern Papua and northern Australia. Phylogenetic position of this turtle is remain unresolved until now. Most of the research conducted show close relationships of C. insculpta and members of Trionychidae family. However, some of the research show distance between C. insculpta and members of Trionychidae family. This research is conducted to analyze phylogenetic relationship between C. insculpta and other members of Testudinata using 12S rRNA, 16S rRNA, and both gene as markers. DNA samples were obtained from three different organisms of C. insculpta. Two species used as outgroups were Alligator mississippiensis and Iguana iguana. Phylogenetic analysis was carried out using Neighbor-Joining method with Felsenstein 1981 (F81) modeltest. A polytomy tree of Testudinata was produced by using 12S rRNA gene. However, analysis using 16S rRNA and both genes as markers confirmed that C. insculpta was located between the Chelonidae and the Trionychidae family.
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