Biodiesel is one of alternative fuels. Biodiesel can be made from coconut oil and is referred to as cocodiesel. Thisresearch studies the optimum condition of cocodiesel production by methanolysis reaction between coconut oiland methanol using heterogen catalyst of calcium carbonate (CaCO 3) is calcined for 1.5 hours at 900oC. In order toget optimum condition, several experimental parameters are applied such as catalyst concentration 1-3 %-wt andmolar ratio of methanol/coconut oil 4:1-12:1. The optimum condition obtained from this experimental as follow:catalyst concentration was 2%, molar ratio of methanol/coconut oil was 8:1 at 600C, produced the higgest conversionof cocodiesel 75.02%. The cocodiesel meet the requirement of Standar Nasional Indonesia (SNI) specifications.Based on data analysis, the product has a qualification as diesel fuel. SNI Biodisel is density (40 0C) 850-890Kg/m3,kinematic viscosity (40 0C) 2,3-6,0 mm2/s, cetane number min 51, iod number max 115 gr iod/100 gram,moisture content max 0,05 % volum, acid number max 0,8 mg KOH/g, flash point min 100 0C.

Penggunaan biomassa mikroalga sebagai bahan baku untuk memproduksi bioetanol sangat menjanjikan, hal ini disebabkan oleh sejumlah besar karbohidrat terdapat dalam fisiologi sel mikroalga. Kendala utama dari hidrolisis enzimatik dalam rangka memproduksi bioetanol adalah terikatnya granula pati dalam dinding sel yang kaku. Oleh sebab itu langkah pre-treatment diperlukan untuk melepaskan dan mengkonversi karbohidrat komplek menjadi gula sederhana sebelum proses fermentasi. Mikroalga spesies Tetraselmis chuii merupakan mikroalga hijau (Chlorophyta) yang mana dinding selnya mengandung selulosa dan hemiselulosa sebagai konstituen utama, oleh karena itu, penelitian ini melihat pengaruh penggunaan enzim selulase dan xilanase sebagai strategi untuk membuka dinding sel mikroalga. Parameter yang berbeda yang akan diselidiki adalah konsentrasi enzim, suhu, pH, serta metode penggunaan enzim. Hasil penelitian menunjukkan bahwa yield tertinggi glukosa yang diperoleh adalah 31,912% (w/w) dan ini dicapai pada kondisi proses suhu 45 0 C, pH 4,5, jumlah biomassa mikroalga 5 g/L, konsentrasi enzim selulase dan xilanase masing-masing 30% (w/w) pada waktu 40 menit pada mekanisme penggunaan enzim selulase dan xilanase secara simultan. AbstractThe use of biomass of microalgae as a feedstock to produce bioethanol is very promising, it is caused by a large amount of carbohydrates contained in microalgae physiology cell. The main obstacle of enzymatic hydrolysis in order to produce bioethanol is the bound starch granules in a rigid cell wall. Therefore, pre-treatment steps needed to remove and convert complex carbohydrates into simple sugars before the fermentation process. Tetraselmis Chuii microalgae species are green microalgae (Chlorophyta) in which the cell wall containing cellulose and hemicellulose as the main constituent, therefore, this study observe the effect of the use of cellulase enzymes and xylanase as a strategy to open up the cell walls of microalgae. Another investigated parameter is the enzyme concentration, temperature, pH, and methods of use of enzymes. The results showed that the highest yield of glucose obtained was 31.912% (w / w) and is achieved under the conditions of a temperature of 45 o C, pH of 4.5, the amount of biomass of microalgae as 5 g/L, the concentration of cellulase enzymes and xilanase 30% (w / w) at 40 minute at mechanism using cellulase and xylanase enzymes simultaneously.

This article aims to describe a new paradigm of sustainable community service. The background is the phenomenon is that there is no mutualism symbiosis of various parties and the key actors of empowerment in fulfilling the needs, challenges, and implementation of the community, either directly or indirectly. The method used in this article is literature studies and from various experiences of the author in doing community service. To run and understand the new paradigm of community service, there are at least three models that can be used, namely triple helix, quadruple helix, and quintuple helix. The dynamics of community empowerment require innovations that support sustainable development. The quintuple helix model is relevant for viewing current and future conditions.

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