Optimization and scale-up of L-lactic acid fermentation by mutant strain Rhizopus sp. MK-96-1196 in airlift bioreactors.
We determined the optimum culture conditions such as inoculum size, initial starch concentration, pH during the fermentation and aeration rate for L-lactic acid production by Rhizopus sp. MK-96-1196 in a 3-l airlift bioreactor. More than 90 g/l of L-lactic acid was produced from only partially enzymatically hydrolyzed corn starch with a production rate of 2.6 g/l/h and a product yield of 87% based on the starch consumed under the optimum conditions in the 3-l airlift bioreactor. Scale-up from the 3-l to a 100-l airlift bioreactor for L-lactic acid fermentation was carried out using V(s)(cm/s) as a scale-up criterion. The production rates and yields of L-lactic acid in both bioreactors appeared to be fairly well correlated with k(L)a (1/h).
Miura
Shigenobu
S
Tokyo Laboratories, Musashino Chemical Laboratory Ltd., 16-2 Miyamae 1-Chome, Suginami-ku, Tokyo 168-0081, Japan.
Arimura
Tomohiro
T
Hoshino
Minako
M
Kojima
Mami
M
Dwiarti
Lies
L
Okabe
Mitsuyasu
M