| Turmeric is the main plant sources of saponin pharmaceutical production. The residue of Turmeric after extracted saponin is a kind of solid waste. Most of the solid waste after saponin production is piled or burned arbitraryly. It not only caused great waste of biomass resources, but also residues of toxic organic or inorganic substances eventually enter into the soil and the water, leading to severe pollution of the environment. At the same time, because the particles of residue is small, loose and low energy density, it also brings atmospheric dust pollution. The main components of residue of saponin production are cellulose, hemicellulose, lignin and starch. Therefore it has good conditions for the conversion of ethanol. It is a rare material of bio-energy production.Based on the residual containing a lot of cellulose material characteristics, this paper used the method of acid-bacteria-enzyme mixed treatment to investigate the saccharification process. To discuss the optimum condition of yeast ethanol fermentation, this study compared simultaneously saccharification fermentation (SSF) with separate hydrolysis fermentation (SHF). Meanwhile, solid fermentation and liquid fermentation under the optimal conditions and yeast mutation were studyed. The results are as follows:(1) Residue after saponin production using Turmeric mainly contained 17.05% cellulose, 10.40% lignin, 0.79% reducing sugar, 24.02% hemicellulose, 33.69% starch. It had good potential for the conversion of ethanol.(2) Residue after saponin production using Turmeric was treated by the method of acid-microorganism-enzyme co-degradation. The results showed that the optimal conditions of the acid-microorganism-enzyme saccharification technology, which used acid to hydrolyze residue first, then lignin in the residue was degraded by Phanerochaete chrysosporium, prior to ethanol enzyme hydrolysis, were as follows. At first, saponin production residue after the high-temperature steam treatment was hydrolyzed by acid under the best conditions, which involved 100℃, ratio of liquid-solid 20:1, the dilute sulfuric acid concentration 4%, hydrolysis time for 120 min; And then the optimum degradation condition of Phanerochaete chrysosporium was: 30℃, pH 6, the bacteria suspension liquid 100 mL/L. Under this condition, the saponin production residue was degraded for 4 d. After fermentation, waste residue degraded continue to be further hydrolyzed by ethanol enzyme. The optimal process of enzyme hydrolysis was quantity of enzyme 0.9 mL, temperature 50℃, pH 4.8, enzymatic hydrolysis time for 100 min. After the saponin production residue was treated under the best conditions, lignin removal rate reached 42.82%, and total reducing sugar yield was up to 59.72%, which was the highest.(3) The factors that impact the SHF were studied respectively by orthogonal tests. The results showed the best conditions for the time 72 h, temperature 31℃, the pH 4.8 and inoculation amount of 10% (v/v). SHF optimal results showed that the order of the factors effecting on the rate of ethanol conversion was temperature> time> pH> inoculation. Under this condition, the conversion rate of reducing sugar is 61.41%, and the ethanol conversion rate is 60.04%.(4) The factors that impact the SSF were studied respectively by single factors and orthogonal tests. The results showed that the optimum conditions for the time 72 h, temperature 38℃, the pH 6.0, inoculation amount of 10% (v/v), and ethanol enzyme dosage 0.9 mL. Under the condition, the conversion rate of reducing sugar is 75.51%, and the ethanol conversion rate is 67.65%. SSF optimal results showed that the order of the factors effecting on the rate of ethanol conversion and the conversion rate of reducing sugar was the same: temperature> time> pH> inoculation. Compared with the two kind of fermentation patterns of SSF and SHF, SSF had the merit such as shorter fermention time, higher ethanol concentration. Fermention time of SHF was 144 h, while fermention time of SSF was 72 h. Fermention time of SSF reduced 72 h. Ethanol concentration of SHF was 60.04%, while ethanol concentration of SSF was 67.65%, and the latter was 7.61% higher than the former.(5) In order to improve the yeast fermentation temperature, the study applied UV mutagenesis and heat shock treatment. And the three mutation bacteria 98#, 6# and 18# were screened. Both of performance of heat-resistant and ethanol tolerance were significantly better than the pro-strain after heat shock induced and UV treatment of strain. Ethanol fermentation tests after yeast mutation results showed that the highest conversion of ethanol was 69.13% after yeast treated with the UV-induced. It was approximately 26% more than the conversion rate of ethanol 55.05% of non-mutation. Under the optimum conditions of liquid simultaneous saccharification fermentation, the ethanol conversion rate was 69.13% after mutation of yeast, while the ethanol conversion rate of the solid simultaneous saccharification fermentation was 67.65%.
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