Studies On Mass Culture Of Nostoc Sphaeroides And N. Commune (Cyanophyta) And The Structural And Physiological Characteristics Of N. Sphaeroides

The cultivation of Nostoc sphaeroides Kützing and N. commune Vauch, the two important economic cyanbacterial strains, were studied on a pilot scale. In this study, the whole process of the cultivation of Nostoc sphaeroides and N. commune was studied. At the same time, the variation of the structure on the colonies of N. sphaeroides, the physiological characteristics on different layers of the colonies and the effect of inoculum density on the growth were investigated. Main results were as follows:N. sphaeroides and N. commune was cultured indoors and outdoors using raceway-shape culture ponds. The culture volume of media was up to 5 m3 indoors. The maximum biomass productivity was about 297.4 Kg (Fw) per month and the average productivity was 180.9 Kg (Fw) per month. The culture temperature higher than 35 0C acutely reduced the biomass productivith considerably. When the culture was proformed outdoors using raceway-shape culture ponds, the productivity of N. sphaeroides and N. commune was up to 445.2 and 269.2 g·m-2·d-1 (Fw), respectively. The productivity of N. commune was positively correlated with the inoculum density when initial density was below 9 Kg/m2. As far as N. sphaeroides was concerned, the breakage of larger colonies led to the decrease in the biomass productivity. The...