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Characteristics of Anaerobic Growth and Wxygen Toxicity of Rhizopus from
Starters Made by Soild State Fermentation
Abstract
Sorghum liquor brewing (SB) is a typical Chinese traditonal process of
solid state fermentation, The obligate aerobie cultures of Rhixzopus
isolated from the natural starter never showed spore germination and
saccharification in solid sorghum mashes; whereas a small portion of the
mashes transferred into a flask or a jar did. It seems that the anaerobic
or microaerobic condition within the dry and compact cake starter may be
selective for the right saccharolytic molds for SB. Since the natural
starter was a kind of undefined mixed cultures, the yield and quality of
sorghum liquor varied every season. Hence, a pure culture of saccharolytic
Rhizopus sp. with microaerophile-like or facultative anaerobic
characteristics might be favorable to SB. The characteristics of anaerobic
growth and oxygenn toxicity in Rhizopus cultures, which were isolated from
dismutase activity among the Rhizopus cultures tested. Six strains,
RT-1-8, RT-43, RT-2, RJP, TBR, and C-1, showed quite low catalase activity
about 3-10 time less than that of RT-3, Rh-6, and A25975. It is
interesting that these six strains also showed definite mycelial growth in
subsurface area, and their aerial hypha growth was much improved by
supplement of the detoxifying agents. Im addition, RT-1-8, RT-43, RT-2,
C-1 and TBR had chlamydospores more than the other cultures, when
cultivated under aerobic condition. However, only a few chlamydospores was
observed under microaerobic condition. It reveals that aerobic condition
may be fairly unfavorable to some Rhizopus cultures, such as RT-1-8,
RT-43, and C-1, but microaerobic condition is favorable.
No direct evidences could account for that catalase deficiency in some
Rhizopus cultures was the main cause of oxygen toxicity in aerobic
condition. In conclusion, It is possible that some Rhizopus cultures from
the starters exhibited both the patterns of microaerophilic and aerobic
growth owing to some physiological changes caused by growth under low
oxygen condition. Since gas diffusion within the compact cake starters is
limited. It appears that the Rhizopus culture with microaerophile-like
characteristics is applicable for the full scale operation of SB, a nearly
anaerobiosis system.
目錄
第一章 緒 論：研究背景及目的
第一節 高梁酒的固態醱酵
1.固態醱酵
2.高粱酒的釀造
3.有關高粱酒醱酵的研究
4.基質初含水量對微生物生長的影響
5.糖化黴菌純粹培養高粱酒醱酵
第二節 混合培養的麴菌特性及固態醱酵的嫌氣生長
第三節 微生物的氧分子代謝及氧毒防衛機制
1.氧分子代謝與氧毒害的生成
2.微生物的超氧物歧化
3.微生物的過氧化氫
第四節 研究目的
參考文獻
第二章 一特異的耐微氧性根黴菌，RT-1-8，的純粹培養高粱酒固態醱酵
中文摘要
前言
材料與方法
結果
討論
參考文獻
第三章 醱酵麴根黴菌的嫌氣生長及氧毒害特性
中文摘要
前言
材料與方法
結果
討論
參考文獻
第四章 麴根黴菌的過佯化氫及超氧物歧化之研究
中文摘要
前言
材料與方法
結果
討論
參考文獻
第五章 結論
英文摘要
附錄(Appendix)
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