Extraction, purification and identification of menaquinones from Flavobacterium meningosepticum fermentation medium

Autor: Fang Zhiwei, Genhai Zhao, Zhiming Zheng, Hefang Wu, Peng Wang, Hongfei Wei, Li Wang
Rok vydání: 2018
Předmět:
Zdroj: Process Biochemistry. 66:245-253
ISSN: 1359-5113
Popis: Menaquinones (MK-n) can be produced by the fermentation of Flavobacterium meningosepticum. This article deals with the process of extraction, purification and identification of MK-4, MK-5 and MK-6. Among the organic solvents tested, the maximum extraction yields (99.1%) were obtained using three successive 20-min methanol extractions. Purification and separation of the menaquinone homologs, extracted from dry microbial cells with methanol, was achieved using adsorption chromatography, gel permeation chromatography and reverse-phase C18 chromatography on columns with large processing capacities (0.95–7.0 mg menaquinones per packing gram). The purities of MK-5 and MK-6 crystals reached 96.3% and 99.2%, respectively, as calculated by the external standard method. High recovery rates of 94.7% (not crystallized), 87.3% and 88.2% of MK-4, MK-5 and MK-6, respectively, were achieved for the overall process from extraction to crystallization. Throughout the entire process, the only organic solvents used were methanol and dichloromethane, facilitating the recycling of these solvents and, hence, application of the method on a large scale. The vitamin K2 homologs were identified as MK-4, MK-5 and MK-6 by MS, IR and 1H NMR.
Databáze: OpenAIRE