Judul: Laju Pertumbuhan Biomassa dan Uji Kadar Karbohidrat Gelidium latifolium pada Kultivasi Menggunakan Sistem Injeksi Co2.
Abstrak: Macro algae is a potential feedstock for bioethanol energy development. The species of macro algae are very diverse in nature so that need to explore and research about biological characteristic, such as biomass growth rate. This research analyzed the levels of carbohydrate yield and measure the biomass growth rate of Gelidium latifolium on carbon dioxide (CO2) injection as source of photosynthesis The research was conducted at Laboratory of Microbiology, Surfactant and Bioenergy Research Center (SBRC) of Bogor Agricultural University, Baranangsiang, on February until July 2012. Macro algae Gelidium latifolium is taken from Ujung Kulon, Banten. Experimental design used is Randomized Block Design (RBD) and Duncan Test with some treatments, namely control, P1 injection of 2.000 cc (200 cc x 10 minutes per 3 days) and aeration, P2 injection of 3.000 cc (200 cc x 15 minutes per 3 days) and aeration, P3 injection of 2.000 cc (200 cc x 10 minutes per 3 days) without aeration, and P4 injection of 3.000 cc (200 cc x 15 minutes per 3 days) without aeration. Initial weight of the Gelidium latifolium cultivation samples are similar, 3 grams and time of cultivation is 42 days. The results showed that the highest average wet weight at the end of cultivation is P2 (4.16 ± 0.14 gram), P1 (4.03 ± 0.12 gram), P3 (0.23 ± 3.66 gram), control (3.54 ± 0.06 gram), and P4 (40.23 ± 3.26 gram). The daily growth rate value of Gelidium latifolium during study ranged from 0.02 to 1.06%. The highest daily growth rate of all treatments occurred in P2 is 1.06 ± 0.14% at 4th week, while the lowest daily growth rate of all treatments occurred in P4 is 0.02 ± 0.85% in the 2nd week . The weight of P4 treatment macro algae decreased drastically in the 2nd week caused by fungi that grow around the thallus. The different treatments make significant effect on the growth rate of Gelidium latifolium, so need a test to determine effect of treatments to growth rate at 95% confidence interval. Carbohydrate yield before cultivation is 18.23%, while after cultivation for control carbohydrate yield is 19.40%, P1 is 20.40%, P2 is 19.40%, P3 is 16.87%, and P4 is 16.40% .
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Judul: Seleksi dan karakterisasi ganggang mikro indigen air tawar sebagai penghasil karbohidrat untuk energi terbarukan
Abstrak: The objective of this research is to explore and isolate indigenous micro algae that have a high carbohydrate producer as potentially for bioethanol production. The exploration from indigenous fresh water fifteen micro algae carried out in a BG 11 media and resulted four different types of micro algae such as ICBB-CC (9111, 9112, 9114 and 6354 PLB). By morpholgical identification, they were identified as Crucigenia quadrata, Scenedesmus bijuga, Chlorella vulgaris, and Chlorella vulgaris respectively. They were cultivated in a 5 L reactor using three types media of BG 11, MBM and PHM. The fastest growing isolate was ICBB 9111 of C. quadrata in MBM medium. The production biomassa of four isolates were developed in the raceway of 90-100L using MBM modifications medium with TSP aims , because of media has a value of optical density (OD) which increased from 0.09 to 0,200 within 3 (three) days. Harvesting is done from the OD value ≥ 0.6 continuously and harvesting stopped at OD values ≤ 0.5. Harvesting by means of filtration and drying naturally at room temperature. Temperature micro algae in ponds ranging channel 30-35 oC and maintained volume in such a way as early cultivation (by adding water to take advantage of existing nutrients). Production of dried-biomass/L/d and the results of the proximate analysis of carbohydrates into four isolates : Crucigenia quadrata ICBB 9111, Scenedesmus bijuga ICBB 9112, Chlorella vulgaris ICBB 9114 and Chlorella vulgaris PLB 6354) is 0,038 (42.27% dry weight), 0,035 (21.30% dry weight), 0.019 (16.66% dry weight) and 0,018 (17.22% dry weight). Production of dry biomass / L / day and the results of the proximate analysis of carbohydrates into four isolates ICBB-CC (9111, 9112, 9114 and 6354 PLB) is 0,038 (42.27% dry weight), 0,035 (21.30% dry weight), 0.019 (16.66% dry weight) and 0,018 (17.22% dry weight). Result of the selection of four types of micro algae ICBB-CC (9111, 9112, 9114 and 6354 PLB,) with modifications MBM TSP aims to get local micro algae isolates that have high carbohydrate content potentially for the production of ethanol.Optimal conditions for hydrolysis process 48 hours using a commercial enzyme that includes two stages: liquefaction process using enzymes α-amylase 600U at 95 ° C with a pH of 6 while for the saccharification process using enzymes amiloglukosidase 145U at a temperature of 60 ° C, pH 4.5 and 120 rpm rotation .Ethanol content of 40-hour fermented using S. Cerevisiae each sample, namely: 9111 amounted to 50.47 ppm, 105.86 ppm for 9112, 9114 amounted to 53.38 ppm and 41.17 ppm of PLB 6354.
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Judul: Grup dan Homomorfisma Grup pada Rubik Revenge
Abstrak: Rubik cube is a kind of puzzle game. A player must arrange rubik sides, which have been disordered, back to the position where every side has the same colour. This paper does not focus on the settlement solution, but instead on proving the existence of a group homomorphism between rubik movement group and S96 symmetric permutation group in rubik revenge. Firstly, it has been proved that rubik movement set is a group. Then, it also has been proved that the M set, which contains numeric labels of 1 until 96 in cubinos sides, is S96 symmetric permutation group.
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