Osmolarity controlled fermentation method for acarbose preparation

摘要

Preparation of acarbose (I) by fermentation is carried out such that: (i) the osmolality is adjusted to and maintained at 200-600 (preferably 300-500) mosmol/kg; (ii) 1 nutrient component is added during the fermentation (preferably to maintain osmolality as in (i), and preferably by continuous addition (optionally together with continuous removal of (I)-containing culture broth) or by portionwise addition); (iii) portionwise removal of (I)-containing culture solution is alternated with portionwise addition of fresh nutrient solution; (iv) fermentation is a through-flow process in which flowing substrate solution is added portionwise or continuously, or (v) fermentation is a continuous process.