Acid and enzymatic hydrolysis of sweet sorghum juice
In order to obtain carbon source available for heterotrophic
microalgal C. protothecoides cultivation, sucrose should be hydrolyzed
to reducing sugars. The hydrolytic methods applied were
acid and enzymatic hydrolysis.
The experiments of acid hydrolysis were carried out at 112 C.
The reaction pH and time were two main factors which can influence
the hydrolysis of sucrose, so the hydrolysis ratio of sucrose
with reaction pH 1–3 and reaction time in the range of 20 to
30 min was investigated. As shown in Table 2, we can appreciate
that the optimal condition of acid hydrolysis was at pH 2 and
112 C for 25 min.
The enzymatic hydrolysis curves of sucrose in SJ with different
dose of invertase ANL were shown in Fig. 2. Within 45 min, the
hydrolysis ratio of sucrose in sweet sorghum juice increased with
the increase of invertase ANL dose. But in 60 min, when invertase
ANL dose was 0.5 and 0.6 ml L1, the hydrolysis ratio reached the