Judul: Hidrolisis Pati dari Empulur Sagu dan Ampas Sagu untuk Produksi Sirup Glukosa
Abstrak: Sago starch is extracted from the pith of sago trunk, while sago hampas is solid waste generated sago starch processing. Sago hampas still contained some starch which depends on the extraction technique. In glucose syrup production, only starch components are hydrolysis by using acid and enzyme. The objectives of this research are to investigate the direct hydrolysis of sago pith and utilization of sago hampas for glucose syrup production, compared to native sago starch. The results showed the high amount of starch in sago pith (86,0%) and sago hampas (55,3%). Glucose syrup produced from enzymatic hydrolysis has higher dextrose content (DE 71-74) compared to acid hydrolysis (DE 33-42). Glucose syrup produced from sago pith and sago hampas have similar characteristic with glucose syrup produced from native sago starch, but with lower yield.
Keyword: enzymatic hydrolysis, acid hydrolysis, sago starch, sago hampas, sago pith

Judul: Sakarifikasi Empulur Sagu (Metroxylon sagu) dengan Konsorsium Enzim Amilolitik dan Holoselulolitik untuk Produksi Bioetanol
Abstrak: Starchy materials such as sago in bioethanol production is one effort in finding solutions to the depletion of fossil fuel reserves but leaving a large amount of wastes. In this research, native sago pith was used directly for bioethanol production. Sago pith is heterogeneous substrates that need pretreatment to reduce the level of crystallinity of fibers and dissolve the starch; also required a number of enzymes to hydrolyze. This research aim is to determine the effects of microwave treatment and consortia of enzymes (α-amylase, amyloglucosidase and pullulanase, cellulase and xylanase) in fermentable sugar production process from the pith of sago palm and its utilization for bioethanol production. This study included the preparation of raw materials sago pith, pith composition analysis including proximate components, starch, amylose and the composition of fiber (cellulose, hemicellulose, and lignin), characterization and preparation of enzymes for determining the optimum temperature, the process of hydrolysis and characterization of syrup. Furthermore, the results of hydrolysis are used in the production of bioethanol in batch and closed systems. The results showed that, microwave treatment made starch easy to swell and break the crystalline structure of fiber. Enzymes consortia in saccharification increased the fermentable sugar production but S. elippsoides used tend to convert glucose into organic acids in spite ethanol.
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Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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