Fig. 2From: Effect of media and fermentation conditions on surfactin and iturin homologues produced by Bacillus natto NT-6: LC–MS analysisConcentration of surfactin homologues (a), iturin homologues (b) and lipopeptide (c) production at different shaking speeds. Values are expressed as mean ± SD, n = 5. The different letters indicate significant differences between treatments (p < 0.05)Back to article page