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"Bakteri telah lama diketahui dapat menghasilkan listrik. Namun, pengembangan teknologi tersebut baru dilakukan beberapa tahun terakhir. MFC (Microbial Fuel Cell) adalah salah satu teknologi yang mengadaptasi prinsip kerja tersebut. MFC berpotensi sebagai penghasil energi listrik alternatif terbarukan melalui konversi limbah menjadi energi listrik. Kenyataaannya, teknologi ini masih menghasilkan listrik yang belum mencapai target nilai voltase minimum. Penelitian ini difokuskan untuk meninjau pengaruh penambahan bakteri gram positif dan negatif serta volume optimal penambahan bakteri gram dengan menggunakan tubular single chamber membranless reactor. Penambahan selektif mixed culture adalah melakukan penambahan gram bakteri masing-masing, yaitu positif dan negatif yang terdapat dalam limbah cair tempe. Gram bakteri ini telah melalui tahap isolasi dan kultur ulang terlebih dahulu sebelum dimasukkan ke dalam substrat sistem MFC. Hasil penelitian didapatkan bahwa penambahan selektif mixed culture dapat meningkatkan produksi tegangan listrik pada sistem MFC. Bakteri gram negatif mendominasi limbah cair tempe dan lebih mampu mentransferkan elektron daripada gram positif. Tegangan bertambah seiring penambahan jumlah bakteri sampai pada titik tertentu yang menyebabkan transfer elektron menurun. Penambahan bakteri gram negatif sebanyak 1 mL memberikan hasil paling optimal yang mampu meningkatkan hasil listrik mencapai 16,50 mV atau 92,14% terhadap eksperimen awal dengan tegangan rata-rata sebesar 17,91 mV. Variasi penambahan optimum ini juga memberikan hasil yang baik pada penggunaan limbah industri, yaitu tegangan dan power density listrik tertinggi sebesar 8,90 mV dan 0,02 mW/m2.

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Bacteria have long been known could produce electricity. However, the development of these new technologies carried out in recent years. MFC (Microbial Fuel Cell) is one of the technologies that adapt that working principle. MFC potential as a producer of renewable alternative electrical energy through the conversion of waste into electrical energy. The fact, this technology still produces electricity that has not reached the target value of the minimm voultage. This research is focused on reviewing the effect of the addition of gram positive and negative bacteria as well as the optimal volume additions gram using a tubular single chamber membranless reactor. The addition of selective mixed culture of bacteria is adding gram respectively, the positive and negative contained in tempe liquid waste. These gram bacteria have been through the stages of isolation and culture before incorporated into the substrate MFC system. The result showed that the addition of selective mixed culture can increase the production of electric voltage on the system MFC. Gram negative bacteria dominate liquid waste tempe and better able to transfer electrons than gram-positive. The voltage increases with increasing number of bacteria up to a point that causes the electron transfer decreases. Addition of gram-negative bacteria in 1 mL provide the most optimal results that can improve the electrical results reached 16.50 mV or 92.14% against the strart experiment with the average voltage of 17.91 mV. Variations optimum additions also give good results on the use of industrial waste, with electrical voltage and power density high of 8.90 mV and 0.02 mW/m2."

"Lovastatin is an anti-cholesterol agent that was produced by Aspergillus terreus using solid state fermentation (SSF). During this fermentation process, sulochrin is also produced as an unwanted co-metabolite. However, our previous result showed that sulochrin had potential as antidiabetes because it is an inhibitor agent of α-glucosidase. In this paper, we reported our observation on lovastatin and sulochrin production pattern in relation with inhibitor α-glucosidase activity during eleven days fermentation of A. terreus koji (SSF) ethyl acetate extract. Koji obtained from solid state fermentation with rice as the substrate and incubated at room temperature, sample is taken daily for eleven day (D-1 toD-11). Lovastatin and sulochrin production was measured by Liquid Chromatography- Mass Spectrometer based on their molecular weight m/z 404.5 and 332.3 respectively. The in hibitory activity is measured by inhibition model of koji extract against α-glucosidase (EC 3.2.1.20) from Saccharomyces cereviceae. The results show that lovastatin production was started on the day 2 (0.04 mg/g) and achieving the optimal production on day 7 (11.46 mg/g), while sulochrin production was started on day 4 (0.60 mg/g) and keep produced until the end of fermentation period at Day 11 (3.11 mg/g). Koji extract was started to show inhibitory to α-glucosidase activity on Day 5 (IC50= 23.34 μg/mL) and keep showed activity until Day 11 (IC50=3.33 μg/mL). These results suggest that inhibitory activity of koji extract to α-glucosidase activity have relation with sulochrin biosynthesis production. "

"Bioetanol telah disepakati pemerintah sebagai bahan bakar alternatif yang perlu dikembangkan. Melalui PERMEN ESDM No. 32 tahun 2008, pemerintah menetapkan program jangka panjang 2016-2025 memfokuskan material lignoselulosa limbah pertanian memasok 4,99 juta kilo liter gasohol. Sorgum manis merupakan tanaman serealia yang mulai dibudidayakan sebagai salah satu penyokong swasembada pangan nasional. Budidaya sorgum kini tidak kurang menghasilkan 1.212.187,03 ton/hektar limbah. Dari hasil analisis limbah sorgum mengandung 22,3184% air, 2,5312% ekstraktif, 6,2579% abu, 26,420% lignin, selulosa dan hemiselulosa. Hidrolisis selulosa limbah sorgum manis varietas unggul Numbu dengan katalis H2SO4 akan menghasilkan glukosa. Fermentasi glukosa oleh Saccharomyces cerevisiae menghasilkan etanol. Penelitian ini dilakukan untuk mengetahui kondisi optimum hidrolisis asam limbah sorgum dan waktu fermentasi untuk menghasilkan yield bioetanol terbesar. Hidrolisis dilakukan pada suhu 121°C selama 30 menit menghasilkan kadar glukosa terbesar 2204,6014 ppm dari 1 gram sampel dengan konsentrasi H2SO4 3%. Perolehan etanol tertinggi dari fermentasi selama 24 jam sebesar 645,00 ppm atau 0,0817% (v/v).

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Bioethanol has been compromised as most potential resource for alternative biofuel. Through PERMEN ESDM No.32/2008, government declared long term program for 2016-2025 focus on processing lignoselulotic materials from agricultural residues supply 4,99 billion liters national gasohol. Sweet sorghum is cerealia plant which is cultivated for supporting in national food self-sufficient program. Sorghum produces up to 1.212.187,03 tons/ha agricultural residues.

From chemical anlysis found that Numbu, the best variety of sweet sorghum consist of 22,184% water, 2,5132% extractive, 6,2579% ash, 26,420% lignin, cellulose and hemicellulose. Acid hydolysis with H2SO4 degrade cellulose in Numbu-waste materials to glucose. Glucose is converted to bioethanol by Saccharomyces cerevisiae fermentation.

This research was done to find optimum condition of acid hydolysis and fermentation time to produce higher bioethanol. Hydolisis run on condition 121°C for 30 minutes yield the highest glucose 2204,6014 ppm from 1 gram sample with 3% H2SO4 concentration.The highest ethanol yield is from 24 hours fermentation which is 645,00 ppm or 0,0816% (v/v)"

"The microbial desalination cell (MDC) is a modification of the microbial fuel cell (MFC) system. The microbial desalination cell is a sustainable technology to desalinate saltwater by directly utilizing the electrical power generated by bacteria during the oxidation process of organic matter. In this study, tempe wastewater will be used as a substrate. Methylene blue (MB) at concentrations of 100 ?M, 200 ?M, and 400 ?M in the anolyte is added as a redox mediator, and the effect on electricity production and desalination performance are evaluated. The average power density increases by 27.30% and 54.54% at MB concentrations of 100 ?M and 200 ?M, respectively. On the other hand, the increase of the MB concentration in the anolyte results in a decrease in the salt removal percentage. The observation made using a scanning electron microscope showed the presence of MB adsorption on the surface of the anion exchange membrane (AEM) and is suspected to be the cause of the disruption of anion transfer between MDC chambers causing a decrease in the salt removal percentage."

"Jartopha curcas L. is a potential source of a non-edible biofuel. Conventional propagation of J. curcas technique has some limitations. Somatic embryo can produce a large number of embryos and obtain a large number of plant ..."

"To provide an interdisciplinary readership with the necessary toolkit to work with micro- and nanofluidics, this book provides basic theory, fundamentals of microfabrication, advanced fabrication methods, device characterization methods and detailed examples of applications of nanofluidics devices and systems. Case studies describing fabrication of complex micro- and nanoscale systems help the reader gain a practical understanding of developing and fabricating such systems. The resulting work covers the fundamentals, processes and applied challenges of functional engineered nanofluidic systems for a variety of different applications, including discussions of lab-on-chip, bio-related applications and emerging technologies for energy and environmental engineering."

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