Judul: Aktivitas enzim ligninolitik fungi pelapuk putih Omphalina sp. dan pleurotus ostreatus pada limbah lignoselulosa
Abstrak: Fungi Pelapuk Putih (FPP) Omphalina sp. dan Pleurotus ostreatus mampu mendegradasi lignin pada limbah lignoselulosa seperti Tandan Kosong Kelapa Sawit (TKKS) dan bagas tebu dengan memproduksi enzim ligninolitik. Penelitian bertujuan mengoptimumkan produksi enzim ligninolitik oleh Fungi Pelapuk Putih (FPP) pada TKKS dan bagas tebu dengan pemberian suplemen CuSO4, dedak, dan kombinasi CuSO4 dan dedak, serta mengkarakterisasi pH optimum enzim ligninolitik. Aktivitas rata-rata tertinggi enzim lakase ditunjukkan oleh isolat P.ostreatus pada media TKKS, pada perlakuan kontrol sebesar 0,223 U/mL, CuSO4 0,546 U/mL, dan kombinasi CuSO4 dan dedak sebesar 0,626 U/mL, berbeda dengan tiga perlakuan lainnya, pada perlakuan dedak aktivitas rata-rata tertinggi enzim lakase sebesar 0,383 U/mL ditunjukkan oleh isolat P.ostreatus pada media bagas tebu. Aktivitas rata-rata tertinggi enzim lignin peroksidase ditunjukkan oleh isolat P.ostreatus pada media TKKS, perlakuan kontrol sebesar 1,983 U/mL, perlakuan CuSO4, dedak, dan kombinasi CuSO4 dan dedak sebesar 2,198 U/mL, 2,061 U/mL, dan 2,372 U/mL. Aktivitas rata-rata tertinggi enzim mangan peroksidase ditunjukkan oleh isolat P.ostreatus pada media TKKS, perlakuan CuSO4 sebesar 0,872 U/mL, dedak 0,923 U/mL, dan kombinasi CuSO4 dan dedak sebesar 0,877 U/mL, sedangkan pada perlakuan kontrol ditunjukkan oleh isolat P.ostreatus pada media bagas tebu dengan aktivitas rata-rata sebesar 0,643 U/mL.. Aktivitas rata-rata enzim ligninolitik optimum pada pH 5.
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Judul: Aktivitas Lakase Pleurotus ostreatus pada Pelepah Sawit dan Tandan Kosong Kelapa Sawit sebagai Substrat
Abstrak: Volume of midrib of oil palm and empty fruit bunches of oil palm (EFB) increase every year. This wastes haven’t been used optimumly. Wastes contain lignocellulosic. Pleurotus ostreatus can degradation of lignocellulosic material, because it has ligninolytic enzymes. One of the ligninolytic enzyme is laccase. This research is aimed to know the laccase activity from two strains of P.ostreatus to hydrolisis substrat of midrib and EFB. Isolate P.ostreatus were isolated from SEAMEO Biotrop baglog and Gadok baglog. Laccase activity in midrib media and EFB media which incubated by JTG was better than incubated by JTB. The laccase activity in midrib media which incubated by JTG was 1,024 U/ml at 30 days, and laccase activity increased 2,002 U/ml at 35. The laccase activity in EFB media which incubated by JTG was 1,561 U/ml at 30 days, and there weren’t laccase activity in EFB media which incubated by JTB and JTG at 35 days after incubation. Protein in midrib media which incubated by JTG was 9,009 mg/ml at 30 days, and increased to 11,371 mg/ml at 35 days. Protein in midrib media which incubated by JTG better than protein in midrib media which incubated by JTB. Protein EFB media which incubated by JTG was 14,535 mg/ml at 30 days. The substrate midrib of oil palm and EFB of oil palm colored light brown after incubation 30 days. The tekstur of substrate midrib of oil palm was crumby. The empty fruit bunches of oil palm tekstur was easier to become apart.
Keyword: Bogor Agricultural University (IPB), Empty fruit bunches of oil palm (EFB)., midrib of oil palm, laccase, Pleurotus ostreatus

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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