Sugarcane Bagasse as a Carrier for the Immobilization of Saccharomyces cerevisiaein Bioethanol Production

Abstract

Sugarcane bagasse was used as a carrier to immobilize Saccharomyces cerevisiae in bioethanol production. This research aims to study the potential use of sugarcane bagasse as an alternative carrier for cell immobilization and improvement in the production process of cell immobilization in bagasse. The results showed that the physical characteristics of sugarcane bagasse as a carrier were water content (7.77 ± 0.35%), water retention (4.80 ± 0.44 g/g), water absorption index (8.58 ± 0.22 g/g), and lignin content (24.40 ± 1.52 %). Determination of cell retention was performed in an inoculum volume of 50 mL yeast suspension with various carrier weights (2.5, 5, 10, and 20 g). The highest cell retention was obtained in ratio of 2.5 g carrier/50 mL cell suspension with cell retention of 5.41 ± 1.06 mg/g, or known as biocatalyst. Biocatalyst, as much as 1.5, 3, 4.5, and 6 g, were used as inoculum for a 24 hour bioethanol fermentation. The best concentration and productivity of bioethanol, obtained by using 3 g of biocatalyst, were 23.95 ± 0.28 g/L and 1.24 ± 0.01 g/L/hours. The average of bioethanol yield for a 24 hour fermentation by using immobilized cells was three times higher than the free cells system. AbstrakBagas sebagai Carrier untuk Imobilisasi Saccharomyces cerevisiae pada Produksi Bioetanol. Bagas digunakan sebagai carrier untuk imobilisasi pada produksi bioetanol. Penelitian bertujuan untuk mengetahui potensi penggunaan bagas sebagai carrier alternatif untuk imobilisasi sel dan perbaikan proses pembuatan imobilisasi sel pada bagas. Hasil penelitian menunjukkan bahwa karakteristik fisik yang dimiliki bagas sebagai carrier yaitu kadar air (7,77 ± 0,35%), retensi air (4,80 ± 0,44 g/g), indeks penyerapan air (8,58 ± 0,22 g/g), dan kadar lignin (24,40 ± 1,52%). Pengukuran retensi sel dilakukan pada variasi berat carrier (2,5, 5, 10, dan 20 g) dengan volume inokulum sebanyak 50 mL suspensi sel. Retensi sel tertinggi, diperoleh pada perbandingan 2,5 g carrier/50 mL suspensi sel, yaitu 5,41 ± 1,06 mg/g dan disebut sebagai biokatalis. Biokatalis sebanyak 1,5; 3; 4,5; dan 6 g digunakan sebagai inokulum untuk fermentasi bioetanol selama 24 jam. Konsentrasi dan produktivitas bioetanol terbaik menggunakan 3 g biokatalis yaitu 23,95 ± 0,28 g/L dan 1,24 ± 0,01 g/L/jam. Rendemen bioetanol selama 24 jam fermentasi menggunakan sel terimobilisasi adalah tiga kali lebih tinggi dibandingan dengan sel bebas.

Fermentation of acidic-pretreated glycerol for enhanced 1,3-PDO production by immobilized Clostridium butyricum JKT 37 on coconut shell activated carbon

“…adsorption in the carriers' cavities and colony development in macropores (AgudeloEscobar et al 2012;Anita et al 2016). FESEM images have con rmed the immobilization of C. butyricum JKT 37 on/into the CSAC through the adsorption mechanism.…”