Fig. 2
From: 3-Methylxanthine production through biodegradation of theobromine by Aspergillus sydowii PT-2
Effect of candidate isolates on theobromine degradation in different substrate concentrations. Theobromine concentrations were 100 mg/L (a), 200 mg/L (b), and 300 mg/L (c), respectively. All data were present by mean value ± SD of three replications. The significance level between A. niger PT-1 and other candidate isolates was assessed by using the independent t-test of SPSS 20.0. * p < 0.05; ** p < 0.01; *** p < 0.001