PENGARUH KADAR OKSIGEN PADA FERMENTASI TANDAN KOSONG KELAPA SAWIT OLEH ASPERGILLUS NIGER TERHADAP PRODUKSI GULA SEDERHANA
HIMMATUN WISDA, Dr. Ir. Sarto, M.Sc; Ir. Prof. Wahyudi Budi Sediawan, S.U., Ph.D
2016 | Tesis | S2 Teknik KimiaIndonesia merupakan salah satu negara penghasil kelapa sawit terbesar di dunia. Setiap pengolahan 1 ton tandan buah segar (TBS) dari kelapa sawit ini akan dihasilkan tandan kosong kelapa sawit (TKKS) sebanyak 22-23 kg. Namun limbah kelapa sawit ini sering menimbulkan masalah karena sulit terurai di alam. Dengan kandungan selulosa yang mencapai 42-52%, tandan kosong kelapa sawit sangat berpotensi dikonversikan menjadi gula sederhana dan apabila dikonversi lagi dapat menghasilkan bioetanol yang lebih bernilai jual tinggi. Penelitian ini bertujuan mempelajari pengaruh kadar oksigen dan pretreatment 1%NaOH (150oC, 2 jam) terhadap produksi gula sederhana oleh jamur Aspergillus niger. TKKS direndam dalam 1% NaOH selama 2 jam. pada suhu 150oC. Medium basal mengandung 10 gr/L KH2PO4, 3 gr/L MgSO4, 3 gr/L CaCl2 dan 5 gr/L yeast ekstrak digunakan untuk pertumbuhan A. niger. Hidrolisis dimulai dengan menambahkan A. niger ke dalam 5 gram TKKS pada erlenmeyer. Inkubasi dilakukan selama 10 hari pada suhu ruang dengan pH awal 6. Pengambilan sampel dilakukan dengan pengukuran pH, konsentrasi gula sederhana dengan metode DNS, dan kadar protein dengan metode Lowry setiap 24 jam. Hasil penelitian menunjukkan pretreatment TKKS dengan 1%NaOH pada suhu 150oC selama 2 jam dapat meningkatkan pertumbuhan jamur dan produksi gula sederhana. Kadar oksigen yang memberikan hasil terbaik yakni aerasi dengan kadar oksigen 21%. Apabila kadar oksigen dikurangi selama aerasi, maka konsentrasi protein dan gula sederhana yang dihasilkan akan menurun pula. Model kinetika yang diajukan dapat menggambarkan secara kuantitatif proses fermentasi padat TKKS oleh jamur A. niger.
Indonesia is one of the largest palm oil producer in the world. One ton of fresh fruit bunches (FFB) produces oil palm empty fruit bunches (OPEFB) as much as 220-230kg. However, the waste of palm oil creates problem as it is difficult to be decomposed in nature. The content of cellulose in OPEFB reaches 42-52%, so that OPEFB can be potentially converted into simple sugar. These molecules can be further converted into bioethanol which is more valuable. This research is focusing on hydrolysis of OPEFB enzymatically using A. niger as enzyme producer. The aim of this research is to study the effect of oxygen content and pretreatment using 1% of NaOH at 150oC for 2 hours to the production of simpler sugar molecules by Aspergillus niger. OPEFB was soaked in 1% of NaOH solution for 2 hours at 150oC. Basal medium which contained 10 g/L of KH2PO4, 3 g/L of MgSO4, 3 g/L of CaCl2 and 5 g/L of yeast extract was made to support A.niger growth. The hydrolysis was started by adding A. niger spores into 5 grams of OPEFB in enlenmeyer. The hydrolysis was carried out for 10 days at room temperature at pH 6. Sampling was done by measuring the pH, concentration of simple sugar molecules using DNS method, and protein content using Lowry method every 24 hours. The results showed that hydrolyisis of OPEFB previously treated by 1% NaOH at 150oC for 2 hours could increase the produced sugar concentration. The most suitable aeration condition was reached with 21% of O2. When the oxygen concentration in was reduced during aeration, the concentration of protein and simple sugar produced would also declined. Kinetics modelling can quantitatively describe the hydrolysis of OPEFB in solid state using A.niger.
Kata Kunci : TKKS, kadar oksigen, aerasi, gula sederhana, Aspergillus niger, fermentasi padat
