Judul: Bioetanol berbahan dasar amaps rumput laut Kappaphycus alvarezii
Abstrak: Berdasarkan catatan Ditjen Perikanan Budidaya Departemen Kelautan dan Perikanan, produksi rumput laut nasional pada tahun 2007 adalah 1.343.700 ton, dengan areal strategis untuk budidaya rumput laut di seluruh Indonesia adalah 21.500 Ha. Besarnya potensi pengolahan rumput laut masih belum diimbangi dengan penanganan limbah pengolahannya. Kandungan limbah yang dihasilkan oleh pengolahan rumput laut salah satunya adalah karbohidrat yaitu berupa selulosa dan sisa karaginanyang tidak terekstrak. Limbah ini dapat diolah secara fermentasi dengan menggunakan biakan Saccharomyces cerevisiae. Khamir dari jenis Saccharomyces cerevisiae dapat memfermentasi gula sehingga menghasilkan etanol. Tujuan dari penelitian ini adlah untuk memanfaatkan ampas rumput laut Kappaphycus alvarezii sebagai bahan baku pembuatan bioetanol dan mengetahui waktu optimum fermentasi dalam menghasilkan bioetanol dalam jumlah maksimal dengan kadar terbaik
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Judul: Produksi Bioetanol dari Rumput Laut Kappaphycus alvarezii Menggunakan Khamir Saccharomyces cerevisiae IPBCC ALXVII
Abstrak: Kappaphyus alvarezii contains carrageenan type polysaccharide which consists galactose as its monomers. After acidly hydrolysis process, galactose can be converted into ethanol through fermentation process. However, some yeasts prefer glucose as their food substrate. One of the yeast from Surfactant and Bioenergy Research Centre (SBRC) Laboratory is Saccharomyces cerevisiae IPBCC ALXVII is expected can convert galactose inside hydrolyzed seaweed into ethanol. This study aims to analyze the potential of S. cerevisiae IPBCC ALXVII in production of ethanol from K. alvarezii seaweed. In this study, the inoculum of S. cerevisiae IPBCC ALXVII was prepared by repeated batch for eight times. Fermentation process used two hydrolyzed seaweed with different concentrate of sugar reductor. Fermentation with 150.46 g/L sugar reductor concentrate produced lower content of ethanol i.e. 1.69 g/L while with 57.33 g/L produced the highest content of ethanol i.e. 14.56 g/L with fermentation efficiency about 49.80%. The optimum fermentation time using S. cerevisiae IPBCC ALXVII was 144 hours.
Keyword: Bogor Agricultural University (IPB), energy, ethanol, hydrolysis, Kappaphycus alvarezii

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology