Isolasi Bakteri Selulolitik dari Bekatul dan Uji Aktivitas Enzim Selulase pada media dengan berbagai sumber Nitrogen

ABSTRAK

Pemanfaatan bekatul telah diterangkan Allah dalam Firmannya surat Ali
'Imran [3]: 191. Penelitian ini bertujuan untuk mengisolasi bakteri selulolitik dari bekatul dan mengetahui bagaimana pengaruh pemberian sumber nitrogen pada media pertumbuhan dalam uji aktivitas enzim selulase isolat bakteri dari bekatul.

Tahapan penelitian meliputi Isolasi dan karakterisasi bakteri selulolitik dari bekatul dengan pengukuran rasio zona bening. Selanjutnya, dipilih satu isolat bakteri dengan rasio zona bening terbesar kemudian dilakukan uji aktivitas enzim selulase pada media pertumbuhan dengan variasi sumber nitrogen 0,4 % (b/v) antara lain: yeast ekstrak, pepton, kalium nitrat dan ammonium nitrat. Data hasil pengukuran dianalisis menggunakan ANOVA One-way dengan bantuan minitab dilanjutkan dengan uji beda nyata terkecil (BNT) 1%.

Hasil penelitian menunjukkan bahwa dari 13 isolat yang berhasil diisolasi, dipilih satu isolat terbaik dengan rasio zona bening sebesar 1,62 yaitu isolat BK 7 dengan karakterisasi bakteri gram negatif, aerob dan endospora positif. Adapun hasil uji aktivitas enzim menunjukkan bahwa yeast ekstrak memberikan aktivitas enzim tertinggi yakni sebesar 0.0021247 unit/ mL. Sedangkan kalium nitrat 0,0014926 unit/ mL; pepton 0,0009025 unit/ mL dan ammonium nitat 0,0001414 unit/ mL.

ABSTRACT

Utilization of rice bran has been described by Allah Swt in holy Qur’an surah Ali 'Imran [3]: 191.This study aimed to isolate cellulolytic bacteria from rice bran and find out how the effects of nitrogen source given to growth media in cellulase enzyme activity assay bacterial isolates from rice bran.

Stages of the research included isolation and characterization of cellulolytic bacteria of rice bran by measuring the ratio of clear zone. And then, choose a bacteria isolate with the largest clear zone ratio activity test of enzyme cellulase was done on growth media with various of nitrogen source 0.4% (w / v) include: extract yeast, peptone, nitrate potassium and nitrate ammonium. The data of measuring result were analyzed by using the measurement results One-way ANOVA with help of Minitab continued by the least significant difference test (LSD) 1%.

The result of research showed that among 13 isolates that were isolated, selected one of the best isolate with clear zone ratio of 1.62 was isolates BK 7 with the characterization of negative gram bacteria, aerobic and positive endospore. The test result of enzyme activity showed that extract yeast gave the highest enzyme activity namely 0.0021247 units/ mL. While nitrate potassium is 0.0014926 units/ mL; peptone is 0,0009025 units/ mL and nitrat ammonium is 0.0001414 units/ mL.