Pengujian Parameter Biji Sorghum Dan Pengaruh Analisa Total Asam Laktat Dan PH Pada Tepung Sorghum Terfermentasi Menggunakan Baker's Yeast (Saccharomyces Cereviceae)

Sorghum, Sorghum bicolor (L) Moench, adalah sereal paling penting kelima setelah beras, jagung, barley dan gandum. Hasil penelitian menunjukkan bahwa kemampuan substitusi biji sorghum terhadap tepung terigu bisa mencapai 50-75%, walaupun nilai protein pembentuk glutennya tidak dapat menyamai tepung terigu. Tujuan dari penelitian ini adalah mempelajari pengaruh waktu fermentasi terhadap penurunan total asam laktat, nilai pH, dan jumlah total khamir (baker's yeast) tanpa menggunakan nutrient kimia tambahan . Analisa komposisi biji sorghum yang diinvestigasi dalam keadaan wet basis dari laboratorium menghasilkan kadar air, lemak, serat, protein, karbohidrat, dan abu masing-masing sebesar 12.85%, 3.10%, 0.56%, 5.87%, 75.82%, dan 1.79%. Untuk nilai energi total dengan metode bomb kalori didapatkan 4375.94 kcal/kg. Pengujian biji sorghum menghasilkan C-organik sebesar 12,47%. Berdasarkan analisa didapatkan hasil optimal dalam membuat tepung sorghum terfermentasi pada proses fermentasi 60 jam dengan jumlah yeast yang dihasilkan 1,7 x 105 sel/ml dengan kondisi yield % asam laktat 0,214%

Potential of Nostoc Muscorum Cultured in Bg-ii Medium as Biodiesel Feedstock Source: Evaluation of Nutrient Requirement for Culture and Its Daily Lipid Content

Increment of industrial development and energy demands for transportation and electricity have increased diesel-fuel uses to fulfil global energy needs. Carbon emission as impact of high fossil diesel use which pollutes the air gradually increases green house gases (GHG) and increases the intensity of acid rains. Furthermore, scarcity of fossil-fuels resources has caused high price of diesel-fuel which in turn to have increased the prices of all commodities. Nostoc muscorum is filamentous Cyanobacteria species which lives both terrestrial and freshwater aquatic environment. This strain has good ability in producing high biomass and potential in producing lipid. In where, Nostoc muscorum has potential as biodiesel feedstock alternative of food-plants sources. This study was conducting to evaluate the potential of Nostoc muscorum cultured in BG-II medium as biodiesel feedstock source. Evaluation of the nutrient requirement of Nostoc muscorum cultured in BG-II medium was done through assimilation of nitrate (NaNO3)-phosphate (K2HPO4). Biomass production as growth parameter was measured by weighing the dried biomass for 14 days of culture. Daily lipid production was evaluated by lipid extraction using Soxhlet method. The result showed that Nostoc muscorum cultured in BG-II medium required 644.6795 mg/L of NO3- and 25.1566 mg/L of HPO4- with the highest biomass production 0.21 grams/300 mL. Furthermore, Nostoc muscorum as multicellular Cyanobacteria could grow well in BG-II medium at SGR 0.0964 μ/day. Lipid production of Nostoc muscorum during cultivation in BG-II for 14 days decreased day by day. The highest lipid production was reached up in day 4th of culture that was 9.53 mg/g. Based on this study, Nostoc muscorum has good potential as biodiesel feedstock through producing high biomass in BG-II medium