Improvement of Panax notoginseng cell culture for production of ginseng saponin and polysaccharide by high density cultivation in pneumatically agitated bioreactors

A Panax notoginseng cell culture was successfully scaled up from shake flas k to 1.0-L bubble column reactor and concentric-tube airlift reactor. High- density bioreactor batch cultivation was carried out using a modified MS me dium. The maximum cell density in batch cultures reached 20.1, 21.0 and 24. 1 g/L in the shake flask, bubble column and airlift reactors, respectively, and their corresponding biomass productivity was 950, 1140 and 1350 mg/(L. d) for each. The productivity of ginseng saponin was 70, 96 and 99 mg/(L.d) in the flask, bubble column and airlift reactors, respectively; and the po lysaccharide productivity reached 104, 119 and 151 mg/(L.d) for each. Furth ermore, a fed-batch cultivation strategy was developed on the basis of spec ific oxygen uptake rate (SOUR), i.e., sucrose feeding before a sharp decrea se of SOUR, and the highest cell density of 29.7 g/L was successfully achie ved in the airlift bioreactor on day 17 with a very high biomass productivi ty of 1520 mg/(L.d). The concentrations of ginseng saponin and polysacchari de reached about 2.1 and 3.0 g/L, respectively, and their productivity was 106 (saponin) and 158 mg/(L.d) (polysaccharide). This work successfully dem onstrated the high-density bioreactor cultivation of P. notoginseng cells i n pneumatically agitated bioreactors and the reproduction of the shake flas k culture results in bioreactors. The cell density, biomass productivity, p roduction titer and productivity of both ginseng saponin and polysaccharide obtained here were the highest that have been reported on a reactor scale for all the ginseng species.