Judul: Hidrolisis Limbah Agroindustri Glukomanan secara Asam dan Enzimatis.
Abstrak: Pengolahan umbi iles-iles (Amorphophallus oncophyllus) menjadi tepung glukomanan menyisakan limbah berupa serbuk padat yang merupakan hasil samping proses pemisahan glukomanan. Limbah tersebut memiliki kandungan pati, serat, serta sisa glukomanan yang masih dapat dimanfaatkan menjadi gula sederhana melalui hidrolisis. Tujuan penelitian ini adalah mengkaji proses hidrolisis limbah agroindustri glukomanan menggunakan metode asam dan enzimatis sebagai pembanding serta untuk mengetahui pengaruhnya terhadap produk dan hasil samping yang terbentuk. Hidrolisis asam menggunakan pemanasan konvensional (otoklaf) dan gelombang mikro dengan asam encer yaitu HCl dan H2SO4 pada konsentrasi 0.5 M dan 1 M. Hidrolisis enzimatis menggunakan konsorsium α-amilase (1.75 dan 3.5 U/g), amiloglukosidase (0.3 dan 0.6 U/g), serta selulase (1 dan 2 U/g). Hasil penelitian memperlihatkan potensi limbah dengan komponen utama terdiri atas pati (47.26 ± 0.29 %), serat (15.79 ± 0.62 %), sisa glukomanan (12.64 ± 0.26 %). Hidrolisis asam menggunakan HCl memberikan hasil yang sedikit lebih tinggi dibandingkan H2SO4. Hidrolisis otoklaf menghasilkan gula dengan DE yang tinggi namun dengan rendemen yang lebih rendah, sedangkan hidrolisis gelombang mikro menghasilkan gula dengan DP dan rendemen yang lebih tinggi. Semakin tinggi konsentrasi asam, nilai gula pereduksi, DE, dan HMF semakin tinggi, namun DP semakin rendah. Pada hidrolisis enzimatis peningkatan dosis enzim memberikan hasil yang tidak berbeda nyata. Perlakuan terbaik diperoleh dari hidrolisis enzimatis dengan dosis normal karena memiliki gula pereduksi dan total gula yang tinggi serta HMF yang rendah.
Keyword: asam, enzimatis, hidrolisis, limbah agroindustri glukomanan

Judul: Pemurnian Glukomanan secara Enzimatis dari Tepung Iles-iles
Abstrak: Glucomannan is typical polysaccharide derived from konjac tuber. Conventional fractionation of glucomannan in konjac flour is by mechanical separation method, but it produces low purity glucomannan flour and needs further purification methods. This research is explored the glucomannan purification by enzymatic hydrolysis directly from konjac flour. Since konjac flour mainly consisted of starch, glucomannan and fiber, in this research sole thermophilic α-amylase enzyme and consortium of enzymes (amylase, xylanase and cellulose) were applied on 50 and 65 oC of incubation temperature for 2 hours. The results showed that consortium of enzymes can not be used for glucomannan purification; because glucomannan component is hydrolyzed by xylanase and cellulose. Glucomannan flour produced from sole α-amylase with incubation temperature of 50ᵒC has the highest yield (42.7%) compared to incubation temperature of 65ᵒC (31.6%). Duration of incubation also influenced to the glucomannan yield, and two hours of incubation time gave the best glucomannan flour with highest yield (37.0%), purity (46.1%), viscosity (42.3 cPs) and good whiteness (12.7%). Enzymatic hydrolysis of konjac flour also produced starch syrup (DE 55.6 – 77.9) as by- products.
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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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