Agritech

Detail Cakupan

The objective of this research was screening of pectinesterase (PE) producing bacteria which are potential in clarification of keprok garut citrus juice (Citrus nobilis var microcarpa) and characterization of the resulted pectinesterase (optimum pH and temperature, pH and thermal stability, KM and Vmaks). The screening result showed that enzyme of isolates AR 2, AR 4, AR 6, and KK 2 was found to be a potential enzyme for clarification of keprok garut citrus juice. Enzyme pektinesterase of isolates AR 2, AR 4, AR 6, and KK 2 had optimum pH at 8; 7.5; 8.5; and 6.5 and stable at pH 4-9, 4-9, 6-9, and 3-8. The optimum temperature enzyme of isolates AR 2 and AR 6 were 55ºC and that of AR 4 and KK 2 were 60ºC. Enzyme of isolate AR 2 was stable at 30-50ºC and inactive at 80ºC, AR 4 and KK 2 were stable at 30-60ºC and inactive at 90ºC whereas AR6 was stable at 30-60ºC and still wasn’t inactive at 90ºC. KM value of isolates AR 2, AR 4, AR 6, and KK 2 were 0.604; 0.338; 0.971; and 0.392 mg/ml. Vmaks value of isolates AR 2, AR 4, AR 6, and KK 2 were 1.218; 0.826; 0.969; and 1.080 u/ml. Pectinesterase enzyme of isolates KK 2 was found to be the most potential enzyme for clarification of keprok garut citrus juice.ABSTRAKTujuan dari penelitian ini adalah untuk melakukan screening bakteri penghasil enzim pektinesterase (PE) yang berpotensi dalam proses klarifikasi sari buah jeruk keprok garut (Citrus nobilis var microcarpa) serta mengetahui karakteristik enzim pektinesterase yang dihasilkan (pH optimum, suhu optimum, kestabilan pH dan suhu, serta nilai KM dan Vmaks). Hasil screening didapatkan isolat AR 2, AR 4, AR 6, dan KK 2 sebagai isolat penghasil enzim pektinesterase yang berpotensi dalam proses klarifikasi sari buah jeruk keprok garut. Aktivitas enzim pektinesterase isolat AR 2, AR 4, AR 6 dan KK 2 berturut-turut optimum pada pH 8; pH 7,5; pH 8,5; dan pH 6,5, serta stabil pada pH 4-9, pH 4-9, pH 6-9, dan pH 3-8. Suhu optimum enzim pektinesterase isolat AR 2, AR 4,