In-situ extraction and separation of salvianolic acid B from Salvia miltiorrhiza Bunge by integrated expanded bed adsorption

This article describes the development of an integrated expanded bed extraction and separation method for in-situ recovery of salvianolic acid B from Salvia miltiorrhiza Bunge. Twenty-five grams of the herb was extracted in a dynamic extraction column for 3 h, while the target was simultaneously absorbed onto an expanded bed column without any further processing. Then, the expanded bed column was eluted with 1 bed volume (BV) of water and 5 BVs of 50% (v/v) ethanol aqueous solution with a flow rate of 2.4 BV/h. From this, 1438.8 mg of salvianolic acids, containing 55.7% of pure salvianolic acid B, was harvested with an 88.0% recovery. Six evaluation parameters – purity, recovery, process throughput, process efficiency, process environmental impact and general process evaluation – were used as indices for evaluation of different methods. The results indicate that the in-situ method we have developed is a promising process for the recovery of salvianolic acid B from the herb of S. miltiorrhiza Bunge.

► This work indicates an in-situ extraction and separation method and its application in target recovery from herbal material.
► The expanded ratio of 1.4 in expanded bed was suitable for recovery of salvianolic acid B.
► The value of general process evaluation parameter in in-situ method was about 8.3-fold of that in the conventional method.