• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.181-185
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• 1983

The possibility of the ethanol fermentation from raw cassava starch without cooking was investigated. Saccharification yield in the simultaneous saccharification-fermentation (SSF) system was compared with that in saccharification of raw cassava starch, using glucoamylase of Aspergillus shirousmi. Although the saccharification yield of raw cassava starch with 10 folds of the enzyme was 60% compared to cooked cassava starch, higher saccharification could be obtained by SSF This result is maybe due to the elimination of end product inhibition in saccharification of raw starch by glucoamylase. Final ethanol yield from raw cassava starch was about 88% under the condition of 3$0^{\circ}C$, 120 rpm shaking after 3 days in the SSF system.

• Animal Bioscience
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• v.36 no.6
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• pp.908-919
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• 2023

Objective: Information about the chemical composition of cassava-based feed ingredients is needed to accurately formulate animal diets. A study was conducted to determine the chemical composition of cassava-based feed ingredients and to test the hypothesis that there is variation in chemical composition among cassava products originating from different South-East Asian countries. Methods: Sources of dried peeled and unpeeled cassava roots, cassava chips, cassava meal, high-ash cassava meal, and cassava residue were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid-hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Samples of peeled and unpeeled cassava roots, cassava chips, and cassava meal were also analyzed for sugars. Results: High-ash cassava meal had greater (p<0.05) dry matter and ash, but lower (p<0.05) total starch and gross energy than all other cassava products. Peeled cassava roots, unpeeled cassava roots, and cassava chips had greater (p<0.05) total starch than the other cassava-based ingredients. Cassava residue had greater (p<0.05) concentrations of lysine, insoluble dietary fiber, and soluble dietary fiber compared with the other cassava products, but tryptophan and glutamic acid were greater (p<0.05) in peeled cassava roots, cassava chips, and cassava meal samples compared with the other ingredients. Concentration of most minerals was greater (p<0.05) in high-ash cassava meal than in the other cassava products. Conclusion: Cassava-based ingredients sold as peeled roots, unpeeled roots, chips, or meal have chemical compositions that are not different from each other, and peeling has little impact on chemical composition. High-ash cassava meal has lower nutritional quality compared with other cassava products due to low starch and gross energy. The high fiber content in cassava residue makes this ingredient more suitable for ruminants and sows than for younger pigs or poultry.

• The Korean Journal of Mycology
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• v.15 no.4
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• pp.231-237
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• 1987

A. niger IMI 41873 was shake-cultured in Cassava starch medium, then mycelial dry weight and mycelial protein were measured. The effects of Cassava starch concentrations, various nitrogen sources and concentrations on the levels of mycelial production and mycelial protein were investigated. The results were as follows; In each medium containg 4%, 6%, 8% and 10% of Cassava starch, mycelial production was 13.35 mg/ml, the medium containg 6% of Cassava starch was proved to be most effective. The levels of mycelial protein in shake culture with medium of 6% Cassava starch and $NaNO_3(1.5\;g/l)$ were the highest. Among nitrate, ammonium sulfate, and urea, the nitrate was the most effective on mycelial production.

• The Korean Journal of Mycology
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• v.15 no.3
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• pp.158-168
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• 1987

Several species of the fungi were isolated from cassava(Manihot esculenta Gruntz) starch which had formed into pellet, those had been stored for a while in southern part of Thailand. The species of Rhizopus, Aspergillus niger, and Aspergillus fumigatus were identified. The experimental results are as follows; Dry weight increases were checked during the static liquid culture with modified Czapek Dox medium to which cassava starch was partly replaced to sugar, Aspergillus niger and Aspergillus fumigatus had grown more than Rizopus species when 6% cassava starch was replaced to sugar and had been cultured for 72 hours. Amounts of mycelial protein of Aspergillus niger were checked, the highest amount was shown in 6% cassava starch involved medium. When nitrogen sources were varied such as ammonium sulfate or urea against sodium nitrate, there was no significant difference in mycelial production. Alpha amylase activity of each fungus isolated here was checked, those of Aspergillus niger have shown the highest peak at 72 hours.

• Mycobiology
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• v.34 no.3
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• pp.128-130
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• 2006

The solid waste of sago industry using cassava was fermented by Aspergillus niger, Aspergillus terreus and Rhizopus stolonifer in solid state fermentation. Cassava waste contained 52 per cent starch and 2.9 per cent protein by dry weight. The amylase activity was maintained at a high level and the highest amylase activity was observed on the $8^{th}$ day in R. stolonifer mediated fermentation. R. stolonifer was more efficient than Aspergillus niger and Aspergillus terreus in bioconverting cassava waste into fungal protein (90.24 mg/g) by saccharifying 70% starch and releasing 44.5% reducing sugars in eight days of solid state fermentation.

• Mycobiology
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• v.35 no.4
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• pp.196-204
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• 2007

The growth and bioconversion potential of selected strains growing on cassava waste substrate during solid state fermentation were assessed. Rhizopus stolonifer showed the highest and the fastest utilization of starch and cellulose in the cassava waste substrate. It showed 70% starch utilization and 81% cellulose utilization within eight days. The release of reducing sugars indicating the substrate saccharification or degradation potential of the organisms reached the highest value of 406.5 mg/g by R. stolonifer on cassava waste during the eighth day of fermentation. The protein content was gradually increased (89.4 mg/g) on the eighth day of fermentation in cassava waste by R. stolonifer. The cellulase and amylase activity is higher in R. stolonifer than A. niger and P. chrysosporium. The molecular mass of purified amylase and cellulase seemed to be 75 KDal, 85 KDal respectively.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.412-422
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• 2019

The present study reports the morphological and molecular characterization of the fungal strain, CMSS06 and evaluates its raw starch hydrolyzing ability in four different agricultural substrates (rice bran, banana peel, cassava tubers, and coconut water). The potential use of each agricultural substrate to replace the expensive fermentation media was evaluated with six different fermentation media: rice bran (RB), banana peel (BP), cassava starch (CS), cassava in coconut water (CSCW), cassava in modified coconut water (CMCW), and pure Coconut water (CW). The fungal strain CMSS06 was identified as Thielaviopsis ethacetica by the analysis of the ITS sequences. The T. ethacetica alpha amylase enzyme exhibited maximum alpha amylase activity at 72 h, pH 7.0, and $40^{\circ}C$ on soluble starch. This species resulted in the highest enzyme activity (mU/ml) of 26.06, 10.89, 58.82, 14.2, and 54.67 with the RB, BP, CS, CSCW, and CMCW fermentation media, respectively. The results indicate that CS can be used as a carbon substrate and CMCW can be used to accelerate the fermentation by T. ethacetica. The enzyme was partially purified by 40-60% ammonium sulphate fraction, and it showed total enzyme activity, total protein content, specific activity, purification fold, and a recovery of 2400 mU, 30 mg, 80 mU/mg, 2.7, and 71.1%, respectively. The molecular mass of the T. ethacetica alpha amylase was estimated on SDS-PAGE, and two bands around 50 kDa and 70 kDa were identified. The present study implies that T. ethacetica can produce alpha amylase, and it can be used to hydrolyze raw starch during the fermentation processes.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.342-356
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• 2016

Purpose: The drying of a thin layer of native cassava starch in a tray dryer was modeled to establish an equation for predicting the drying behavior under given conditions. Methods: Drying tests were performed using samples of native cassava starch over a temperature range of $40-60^{\circ}C$. We investigated the variation in the drying time, dynamic equilibrium moisture content, drying rate period, critical moisture content, and effective diffusivity of the starch with temperature. The starch diffusion coefficient and drying activation energy were determined. A modification of the model developed by Hii et al. was devised and tested alongside fourteen other models. Results: For starch with an initial moisture content of 82% (db), the drying time and dynamic equilibrium moisture content decreased as the temperature increased. The constant drying rate phase preceded the falling rate phase between $40-55^{\circ}C$. Drying at $60^{\circ}C$ occurred only in the falling rate phase. The critical moisture content was observed in the $40-55^{\circ}C$ range and increased with the temperature. The effective diffusivity of the starch increased as the drying temperature increased from 40 to $60^{\circ}C$. The modified Hii et al. model produced randomized residual plots, the highest $R^2$, and the lowest standard error of estimates. Conclusions: Drying time decreased linearly with an increase in the temperature, while the decrease in the moisture content was linear between $40-55^{\circ}C$. The constant drying rate phase occurred without any period of induction over a temperature range of $40-55^{\circ}C$ prior to the falling rate period, while drying at $60^{\circ}C$ took place only in the falling rate phase. The effective diffusivity had an Arrhenius relationship with the temperature. The modified Hii et al. model proved to be optimum for predicting the drying behavior of the starch in the tray dryer.

• Microbiology and Biotechnology Letters
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• v.12 no.4
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• pp.261-264
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• 1984

The optimal condition of the ethanol fermentation from raw cassava starch by simultaneous saccharification - fermentation (SSF) was studied using glucoamylase from Aspergillus sp. and a yeast strain. The rate and yield of ethanol production were optimum at pH 3.6 with shaking. The fine milling treatment was effective for both saccharification and SSF of raw cassava starch. The presaccharification at 6$0^{\circ}C$ for 1 hr before SSF increased the rate and yield of ethanol production, as well. To increase the ethanol concentration after fermentation the substrate concentration could be increased up to 2195 without the problem of viscosity. The use of high concentration ethanol tolerant yeast strains and high substrate concentration produced ethanol higher than 10%(W/V) after fermentation for 5 days.

• Preventive Nutrition and Food Science
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• v.7 no.2
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• pp.133-138
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• 2002

To examine the cholesterol-towering effects of extruded products made with cassava starch (CS) and blends of cassava starch with either resistant starch (CS-RS) or oat fiber (CS-OF) hamsters were fed with diets containing a high-cholesterol (2%) and high-fat (17%) diet for 20 days. Hamsters fed with a diet containing no cholesterol were used as a control. Total cholesterol (TC) levels in the CS-RS and CS-OF groups were significantly (p>0.05) lower compared to the CS group by 11.5% and 8.5%, respectively. Also, the diets containing fibers decreased the value of low-density lipoproteins plus very low-density lipoproteins fraction by 32.4% (CS-RS diet) and 51.7% (CS-OF), respectively, as compared to the CS diet. Total lipid values were significantly (p<0.05) lower in hamsters fed the CS-RS diet (916 mg/dL) and CS-OF diet (964 mg/dL) as compared to those fed the CS diet (1661 mg/dL). The results obtained in this study suggest that extruded products containing cassava starch blended with either resistant starch or oat fleer, could prevent health problems associated with high levels of cholesterol and hypertriglyceridemia induced by a high cholesterol and fat diet.