Abstract: The objective of this work was to produce citric acid from corn starch using a newly isolated mutant of Aspergillus , and to analyze the relationship between changes in the physiological properties of A. induced by carbon ion irradiation and citric acid accumulation. Our results showed that the physiological characteristics of conidia in A. niger were closely related to citric acid accumulation and that lower growth rate and viability of conidia may be beneficial to citric acid accumulation. Using corn starch as a raw material, a high-yielding citric acid mutant, named HW2, was obtained. In a 10-L bioreactor, HW2 can accumulate 118.9 g/L citric acid with a residual total sugar concentration of only 14.4 g/L. This represented an 18% increase in citric acid accumulation and a 12.5% decrease in sugar utilization compared with the original strain.

碳离子束诱导黑曲霉生理特性的改变与其柠檬酸积累关系的研究

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