Efektivitas Kombinasi Pakan Ampas Tahu dan Pelet untuk Pertumbuhan Ikan Lele Sangkuriang (Clarias SP)

Pakan merupakan bagian utama dalam menunjang keberhasilan kegiatan budidaya yang dilakukan. Dengan demikian, diperlukan kajian yang intensif untuk mencari formulasi yang tepat agar tujuan tersebut dapat tercapai secara optimal. Penelitian ini dilakukan untuk menguji persentase yang optimal antara ampas tahu dengan pelet untuk meningkatkan pertumbuhan ikan lele sangkuriang dan menekan biaya pakan seminimal mungkin. Metode analisa data yang digunakan berupa rancangan acak kelompok non-faktorial dengan 5 (lima) perlakuan dan 3 (tiga) kali ulangan, selanjutnya data dianalisis dengan uji F. Perlakuan tersebut berupa: 1) Pakan A: Ampas tahu 80% + pelet 20%; 2) Pakan B: Ampas tahu 60% + pelet 40%; 3) Pakan C: Ampas tahu 40% + pelet 60%; 4) Pakan D: Ampas tahu 20% + pelet 80%; dan 5) Pakan E: Pelet 100% (kontrol). Parameter penelitian meliputi efisiensi pakan, laju pertumbuhan ikan, dan kelangsungan hidup. Hasil penelitian menunjukkan bahwa nilai efisiensi pakan terbaik pada pakan kontrol (pelet) sebesar 77,61%, laju pertumbuhan harian ikan lele sangkuriang yang terbaik diperoleh dari pakan pelet (kontrol) sebesar 3,64%. Sementara untuk kelangsungan hidup yang terbaik didapat pada perlakuan pakan B dan C yaitu sebesar 100%.Feed is a major part in the success of farming activities undertaken. Thus, the necessary intensive study to find the right formulation so that these objectives can be achieved optimally. This study was conducted to test the optimal percentage of tofu by product (TbP) with the pellets to increase fish growth and suppress catfish feed costs to a minimum. Data analysis method used in the form of non-factorial randomized design with 5 (five) treatments and 3 (three) replications, then the data were analyzed by F test. These treatments include: 1) Feed A: TbP 80% + 20% pellets; 2) Feed B: TbP 60% + 40% pellets; 3) Feed C: TbP 40% + 60% pellets; 4) Feed D: TbP 20% + 80% pellets; and 5) Feed E: Pellet 100% (control). Parameter research include feed efficiency, growth rate of fish, and survival. The results showed that the best feed efficiency in the control diet (pellets) amounted to 77.61%, daily growth rate of fish catfish are best obtained from feed pellets (control) of 3.64%. While survival is best obtained at treatment of feed B and C equal to 100%

Theoretical investigation on electron transfer-based antioxidant activity of melinjo resveratrol

We employ density functional calculations to study the electron transfer-based antioxidant activity of resveratrol derivatives from melinjo. The derivatives are monomer resveratrol which is trans-resveratrol, and dimer resveratrol which are gnetin C, gnetin L, and gnemonoside C. The results show that gnetin C has the lowest adiabatic ionization potential both in gas phase and water environment. Furthermore, our results demonstrate that dimer resveratrol is consistent to have better electron transfer ability than its monomer. This may due to the destabilization of the high occupied molecular orbital energy of resveratrol. However, the presence of glucoside in gnemonoside C does not affect the electron transfer-based antioxidant activity of dimer resveratrol

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