Pengaruh Proses Freeze-Drying dan Penyimpanan pada Suhu Kamar terhadap Viabilitas dan Patogenisitas Plasma Nutfah Mikroba Pasteurella Multocida - Siti Chotiah (Balai Besar Penelitian dan Pengembangan Bioteknologi dan Sumberdaya Genetik Pertanian, 2006)
The effect of freeze-drying process and preserving in a vacuum at room temperature against viability and pathogenicity of veterinary microbe germ plasma of Pasteuerella multocida BCC 2331 was investigated at Balitvet. The aim of this study was to find out the most effective and efficient conservation method. As much as 5,2 x 1011 colony forming unit (CFU)/ml of bacteria suspension in 7.5% glucose serum as the preservation medium being pathogenic in mice with LD50 of 9,8 CFU/ml was freeze dried then stored at room temperature (±27oC) until the study was completed. Viability and pathogenicity test were done immediately after the process, 1 and 2 months after storage. The results showed that there were viability decreases amounted 1,3 x 101 CFU/ml, 102 CFU/ml and 8,2 x l02 CFU/m1 due to the effects of the process, one month and two-month storage respectively. The decreases of pathogenicity on mice were shown by the increases of LD50 amounting log 1, log 2, and log 3 a day after the process, one month and two-month storage respectively. AbstrakPengaruh proses kering beku dan penyimpanan hasil proses pada suhu kamar 27oC terhadap viabilitas dan patogenisitas plasma nutfah mikroba veteriner telah dipelajari di Balitvet untuk menentukan cara pelestarian yang efektif dan efisien. Dalam kegiatan ini dipakai bakteri Pasteurella multocida koleksi Balitvet Culture Collection nomor koleksi B2331. Suspensi bakteri sebanyak 5,2 x l011 coloni forming unit (CFU)/ml dalam medium preservan 7,5% glukosa, serum dan bersifat patogen pada mencit dengan LD50 9,8 CFU/ml diproses kering beku, kemudian disimpan pada suhu kamar (+27oC) sampai penelitian selesai. Uji viabilitas dan patogenisitas dilakukan langsung setelah proses dan pada 1 serta 2 bulan setelah penyimpanan. Hasil penelitian menunjukkan terjadi penurunan viabilitas sebanyak 1,3 x 101 CFU, dan 8,2 x 102 CFU/ml masingmasing karena pengaruh proses, pengaruh penyimpanan selama 1 dan 2 bulan. Patogenisitas pada mencit menurun yang ditandai oleh adanya peningkatan LD50 sebanyak log 1, log 2, dan log 3 masing-masing 1 hari setelah proses, 1 dan 2 bulan setelah penyimpanan.