Abstract Isolation of soil fungi from landfill in Medan, North Sumatera, Indonesia was conducted. The aim was to investigate the fungal that potential to decolorize waste liquid batik home industry. Results showed that twenty-three species of filamentous fungi were successfuly isolated. All of the isolates were cultured in minimum salt medium containing waste liquid batik at concentration 25, 50, and 75%. At 75% waste, only 4 fungal isolates (Ys02, Ys13, Ys14, and Ys21) showed growth response. Cultured of the fungal isolates in minimum salt medium with 25% waste + 0.5% glucose were found three fungal isolates (Ys02, Ys14, and Ys21). Whereas, medium with 25% waste with no glucose were found only two fungal isolates (Ys14, and Ys21).
Salah satu inovasi dari pengembangan energi alternatif adalah biogas. Biogas merupakan salah satu jenis energi terbarukan yang terbentuk melalui fermentasi bahan-bahan limbah organik, seperti kotoran sapi, sampah organik, serta bahan-bahan lainnya oleh bakteri metanogenik dalam kondisi anaerob (tanpa oksigen). Biogas sangat potensial sebagai sumber energi terbaru karena kandungan methan (CH4) yang tinggi dan nilai kalornya cukup tinggi. CH4 mempunyai nilai kalor 50 Mj/kg. Methan (CH4) yang memiliki satu karbon dalam setiap rantainya, dapat menghasilkan pembakaran yang lebih ramah lingkungan dibandingkan bahan bakar berantai karbon panjang. Hal ini disebabkan karena jumlah CO2 yang dihasilkan selama pembakaran bahan bakar berantai karbon pendek adalah lebih sedikit. Penelitian ini dilakukan untuk mengetahui proses terjadinya gas apabila perbandingan kotoran dan air yaitu : 1:1, 1:2, 1:3. Pada proses yang mengalami perubahan yang signifikan akan digunakan sebagai proses pencampuran selanjutnya. Pengukuran tekanan menggunakan manometer U, dengan waktu pengamatan interval waktu 2 jam. Tekanan biogas paling tinggi yaitu 0,432 kPa dengan perbandingan kotoran : air = 1:3 dan terendah 0,162 kPa dengan perbandingan air : kotoran = 1:1. Jadi dapat disimpulkan bahwa perbandingan 1:3 lebih besar dibandingkan dengan 1:1 dikarenakan proses berkembang biaknya bakteri lebih cepat didalam digester.
In the midst of demands to reduce dependence on fossil energy sources that are decreasing, this research was conducted as an effort to make bioethanol as an alternative energy source. The purpose of this study was to determine the effect of yeast variation on pH and bioethanol content. This research was conducted using the method of Completely Randomised Design (CRD) factorial pattern involving one main factor, namely yeast variation with three replicates for each treatment. Parameters in this study are pH testing and bioethanol content. The best results of both peremeter is the best pH contained in the 3rd treatment with an average amount of 4.84, in testing the bioethanol content of the best value contained in the 3rd treatment with the amount of yeast 6 grams of ethanol content average 0.9%. It can be concluded that bioethanol content is influenced by yeast, distillation, and fermentation time. the higher the yeast, the higher the pH, alcohol density, and yield produced.
