農畜産 廢棄物의 嫌氣的 處理工程에 적용하기 위하여 亞寒帶 지역으로부터 分離한 Methanogen의 生化學的 特性을 조사한 결과는 다음과 같다. 低溫에서도 메탄生成量이 많았던 늪지 堆積物(Canada, 56.9。N)에서 分離된 菌은 Methanobacterium M-251, Methanobacterium M-253, 湖水 堆積物 IV(Canada, 55.0。N)에서 分離된 菌은 Methanosarcina mazei M-372, 갯벌흙 II(Korea, 37.0。N)에서 分離된 菌은 Methanobacterium formicicum M-375로 각각 동정되었다. 分離된 4종의 메탄균은 당분해능은 없으며 적정 pH는 M-251, M-375는 6.8, M-253은 6.5, 그리고 M-372는 7.0이었다. 最適 生育溫度는 M-251과 M-253은 30℃이었고 M-272와 M-375는 37℃이었다. 最低 生育溫度는 M-251, M-253은 8℃이었고, M-372, M-375는 13℃이었다. 分離菌株의 生育量은 30℃에 비하여 17.5℃에서 培養할 때 32∼50% 정도 낮았다. M-251, M-253, M-375의 菌體 生産量은 0.38∼1.21 g/1M CH₄ 범위 이었으며 M-372는 1.14∼1.51 g/CH₄범위이었다.

This study was conducted to investigate the biochemical properties of isolated bacteria, low temperature tolerant methanogens which were selected for use as inoculum for anaerobic fermentation of agricultural and livestock wasted at low temperature. The results, obtained were summarized as follows: Low temperature tolerant methanogens were isolated from the samples which showed the high methanogenesis rate by enrichment culture at low temperature in methanol medium. These methanogens, Methanobacterium M-251 and Methanobacterium M-253 were isolated from swampy sediment at latitude 56.9°, Methanosarcina mazei M-372 from lake sediment IV at latitude 55.0。N, and Methanobacterium formicicum M-375 from tidal land soil at latitude 37.0。N, respectively. The isolated anaerobic bacteria could not use sugars as carbon sources. The optimum pH value for the growth of M-251 and M-375 was 6.8, but those for M-253 and M-372 6.5 and 7.0, respectively. The minimum growth temperature of isolated, M-251 and M-253 were 8℃ and the optimum temperature 30℃, while the minimum of M-392 and M-395 were 13℃ and the optimum 37℃. The growth rate of isolates at 17.5℃ were lower by 32-50% than that of 30℃. The isolated Methanobacterium strains such as M-251, M-253, and M-375 have lower cell yield, 0.38-1.21g/1M CH₄than 1.14-1.51g/1M CH₄of Methanosarcina mazei M-372.