Biomedical Engineering Reference
In-Depth Information
Radix pueraria
Steam explosion (0.8-1.0MPa,2-4min)
Yeast
Saccharifying enzyme
Solid state fermentation
50% ethanol
distrilltation
Ethanol
residues
Vacuum concentration
Ethanol precipitation
liquid
solid
Ethanol reflux
Ethanol supernatant
fiber wasters
Concentration
Fiber
(paper materials)
Protein
(protein feed)
Macroporous
adsorption
resin to refine
Total isoflavones
Fig. 10.24
Ethanol and isoflavone production from steam-pretreated
Radix pueraria
by solid-state
fermentation
the smash energy consumption and hinder the highly effective dissolution of the
starch from
Radix puerariae
. Furthermore, liquid fermentation easily produces a
great deal of wastewater, which would cause serious environmental pollution and
make it difficult to extract
Radix puerariae
isoflavones.
In the last 20 years, I and my colleagues started a promising journey in
biomass utilization through the development of solid-state fermentation and steam
explosion technology. Aiming at the foregoing problems of the fermentation of
Radix puerariae
, low-pressure steam explosion was introduced to pretreat
Radix
puerariae
, then the production of ethanol by simultaneous saccharification and
fermentation of steam-pretreated
Radix puerariae
was presented. The isoflavones
were extracted from the fermentation residues. The gelatinization process of the
starch is replaced by an unpolluted steam explosion pretreatment, reducing energy
consumption. The fiber structure of the materials would be destroyed to improve
the dissolution efficiency of the
Radix puerariae
starch and isoflavones. Solid-state
fermentation is a clean technology by which it is easy to extract isoflavones from
the fermentation residues [
48
-
52
]. The process was shown in Fig.
10.24
.
Optimal technological conditions were obtained:
Radix puerariae
was steam
pretreated at a saturated vapor pressure of 0.8 MPa for 3.5 min; glucoamylase
(65 U
g
1
), 0.1 % (NH
4
)
2
SO
4
,0.1%KH
2
PO
4
, and activated
yeasts were added, and fermentation took place at 35-37
ı
C for 60 h. Under
g
1
), cellulase (1.5U
