PENGARUH KONDISI KULTUR PADA AKTIVITAS SELULASE ISOLAT Pycnoporus sp. DAN Phlebiopsis sp. (EFFECTS OF CULTURE CONDITIONS ON CELLULASE ACTIVITIES PRODUCED BY Pycnoporus sp. AND Phlebiopsis sp.)

The effects of media, pH and temperature on cellulase-complex enzyme produced by Pycnoporus sp. FORDACC-03452 and Phlebiopsis sp. FORDACC-02482 cultivated in rice bran and corn cobs media under solid state fermentation with pH 4–7 and temperature 30°C–45°C were investigated. Rice bran media showed a propensity to induce endo-β,1,4-glucanase and cellobiohydrolase productions, while corn cobs media induce β-glucosidase production. However, the mixture of rice bran and corn cobs did not result in better cellulase complex enzyme activities. Cellulase-complex produced by Pycnoporussp. showed superior activities compared to those produced by Phlebiopsissp. Crude enzyme of Pycnoporus sp. showed optimum specifc-activities of endo-β-1,4-glucanase at pH 6, temperature 35°C (0.403 ± 0.010 IU/mg), cellobiohydrolase at pH 6, temperature 40°C (0.540 ± 0.020 IU/mg) and β-glucosidase at pH 4, temperature 30 °C (0.022 ± 0.001 IU/mg). While Phlebiopsis sp. showed optimum specifc-activities of endo-β-1,4-glucanase at pH 6, temperature 35°C (0.202 ± 0.005 IU/mg), cellobiohydrolase at pH 4, temperature 45°C (0.180 ± 0.002 IU/mg) and β-glucosidase at pH 6, temperature 45°C (0.007 ± 0.001 IU/mg). Due to low β-glucosidase activities, the cellulase-complex generated from this study were not able to completely hydrolyse lignocellulosic waste and yielded unsufficient sugars content. Further investigation to optimize cellulase-complex production from these fungal isolates is still required.ABSTRAKPenelitian pengaruh media kultivasi, pH dan suhu inkubasi terhadap produksi enzim selulase-kompleks dari Pycnoporus sp. FORDACC-03452 dan Phlebiopsis sp. FORDACC-02482 yang ditumbuhkan di media dedak padi dan tongkol jagung dengan metode kultur padat pada variasi pH 4–7 dan suhu 30°C–45°C, telah dilakukan. Hasil memperlihatkan bahwa media dedak padi cenderung menginduksi produksi endo-β-1,4-glukanase dan selobiohidrolase, sedangkan media tongkol jagung menginduksi produksi β-glukosidase. Namun, campuran kedua substrat tersebut tidak menghasilkan aktivitas selulase yang lebih baik. Selulase-kompleks yang dihasilkan Pycnoporus sp. menunjukkan aktivitas lebih baik dibandingkan dengan yang diproduksi Phlebiopsis sp. Filtrat kasar Pycnoporus sp. menunjukkan aktivitas-spesifk endo-β-1,4-glukanase optimum pada pH 6, suhu 35°C (0,403 ± 0,010 IU/mg); selobiohidrolase pada pH 6, suhu 40°C (0,540 ± 0,020 IU/mg); dan β -glukosidase pada pH 4, suhu 30°C (0,022±0,001 IU/mg). Sementara, Phlebiopsis sp. menunjukkan aktivitas-spesifk endo-β-1,4-glukanase optimum pada pH 6, suhu 35°C (0,202 ± 0,005 IU/mg); selobiohidrolase pada pH 4, suhu 45°C (0,180 ± 0,002 IU/mg); dan β-glukosidase pada pH 6, suhu 45°C (0,007 ± 0,001 IU/mg). Rendahnya aktivitas β-glukosidase menyebabkan selulase-kompleks dari penelitian ini belum dapat menghidrolisis limbah lignoselulosa dengan sempurna dan kadar glukosa yang diperoleh masih rendah. Oleh karena itu, optimasi produksi selulasekompleks dari Pycnoporus sp. dan Phlebiopsis sp. masih perlu diteliti lebih lanjut.