Fig. 4

Menaquinone and tocopherol level change in response to 4a and 4c compounds treatment. Comparison between treatment with 6.5 µM of 4a and 3.75 µM of 4c and untreated (control) culture, after purification by RP-HPLC. The analyzed fractions, corresponding to the retention times of the standards are: MQ—16 min and TC—17 min. An asterisk indicates a significant difference compared to untreated controls (P values of < 0.05). MQ menaquinone, TC tocopherol