EFFECT OF LOW pH ON CONTINUOUS CITRIC ACID FERMENTATION BY ASPERGILLUS NIGER
نویسندگان
چکیده
The present study is concerned with the effect of low pH on continuous citric acid fermentation by Aspergillus niger strain SK-17. Microbial cultivations were carried out in a stainless steel stirred bioreactor of 15 L total capacity. The bioconversion of glucose to citric acid at low pH was investigated on cellulose fabric. Sucrose solution (100 g/l) was made to flow through capillaries of a vertical fabric support and oxidized to citric acid at the interface. Conditions of temperature, humidity, airflow and glucose feed rate were optimised. The emerging broth contained a product concentration of 120-140 g/l of citric acid, which is higher than the expected [maximum of 109 g citric acid per 100 g sucrose] as a result of evaporative concentration during the downward flow.
منابع مشابه
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