Title:High Level of Menaquinone-7 Production by Milking Menaquinone-7 with Biocompatible Organic Solvents
Volume: 19
Issue: 3
Author(s): Dinali Ranmadugala, Alireza Ebrahiminezhad*, Merilyn Manley-Harris, Younes Ghasemi and Aydin Berenjian*
Affiliation:
- Department of Pharmaceutical Biotechnology, School of Pharmacy and Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz,Iran
- Faculty of Science and Engineering, The University of Waikato, Hamilton,New Zealand
Keywords:
MK-7, B. subtilis, milking, fermentation, viability, n-hexane, n-butanol.
Abstract: Background: The effect of milking menaquinone-7 (MK-7) with biocompatible organic
solvents on MK-7 production in B. subtilis fermentation was studied. Periodic milking of MK-7 from
the fermentation medium by n-hexane significantly enhanced the total MK-7 production ~ 1.7 fold at
the end of 72 hours of fermentation (p < 0.05) as compared to the control medium.
Methods: Milking of MK-7 with a mixture of n-hexane phase modified with n-butanol was also
explored. Although milking of MK-7 by a mixture of n-hexane and n-butanol (1:2, v/v), was found to
be appropriate in terms of high extraction capacity, no significant increase in total MK-7 concentration
was observed. Biocompatibility between the extraction solvents and B. subtilis was also examined.
Results and Conclusion: The results indicated that the mixture of n-hexane and n-butanol exhibited
some detrimental effects. However, n-hexane alone exhibited delayed toxicity starting at 84 hours of
periodic milking and could, therefore, be considered as the most promising organic solvent for milking
MK-7 in B. subtilis fermentation while enhancing the productivity of the system.