In the submerged cultures of R. oryzae BCRC 33071 and R. oryzae
ATCC 9363, the chemical damage on fungal cells resulting from
ammonia, a neutralizing agent, was successfully reduced when
ammonium bicarbonate and urea were added to ammonia water.
More lactic acid was produced in submerged fermentation with R.
oryzae BCRC 33071 than that with R. oryzae ATCC 9363. Compared
to other work which using ammonia as neutralizing agent, this
method improved the productivity of lactic acid by 15%.