Five ratios of RSC to wheat bran (5:5, 6:4, 7:3, 8:2 and
9:1) were used to study their effects on the degradation
rate of Gls in RSC (Figure 1A). When the ratio was 6:4
or 7:3, A. niger cell grew well and degradation rate of
Gls significantly higher (P < 0.05) than 5:5. When RSC
content increased to 80% or 90%, both filamentous fungi
growth and the degradation rate of Gls (36.98% and
31.97%) markedly decreased (P < 0.05). The above results
showed the optimum ratio of RSC to wheat bran in solid
medium was 6:4 or 7:3. Fermented medium containing
70% RSC was selected and used for subsequent studies.
The optimal temperature for the degradation rate of
Gls was found to be 34°C (Figure 1B), indicating this
temperature being favorable for A. niger growth in RSC
medium. The degradation rate in FRSC was 69.16% at
34°C, markedly higher (P < 0.05) than at 28°C and 31°C,
but there was no significant difference (P > 0.05) with
FRSC at 37°C.