Fig. 3From: Application of methanol and sweet potato vine hydrolysate as enhancers of citric acid production by Aspergillus niger Citric acid accumulation (a), pH values change (b), reducing sugar consumption (c) and citrate synthase activities (d) of A. niger sp. ZJUY under different cultivation conditions. Citrate synthase activities are the values determined at the end point of fermentation. SM SVH and methanol, S SVH, M methanol, O the original conditionsBack to article page