Production of a raw starch saccharifying amylase byBacillus alvei grown on different agricultural substrates

Achi, O. K.; Nijoku-Obi, A. N. U.

doi:10.1007/bf01195849

Cited by 16 publications

(14 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…From the view points of energy utilisation and process simplicity, industrial conversion of starch with raw starch saccharifying amylase represents an economically superior alternative to the conventional process which uses pregelatinised starch as substrate * To whom correspondence should be addressed. (Forgarty 1983;Bergmann et a1 1988;Achi and Njoku-Obi 1992). However, only few microorganisms seem to possess the ability to express raw starch saccharifying enzyme (Taniguchi et This paper reports the effects of starches from various tropical agricultural commodities on the production and raw starch digesting activities of a crude amylolytic enzyme preparation from Aspergillus niger isolated from rotting cassava tubers.…”

Section: Introductionmentioning

confidence: 99%

Production of raw starch digesting amylase by Aspergillus niger grown on native starch sources

Okolo

Ezeogu

1995

J Sci Food Agric

View full text Add to dashboard Cite

Aspergillus niger isolated from rotting cassava produced raw starch degrading amylase on cassava, maize, sorghum and soluble potato-derived starch as the sole carbon source without prior gelatinisation. Maximum activity of the amylase was attained using cassava starch as substrate. The crude enzyme solution which comprised a mixture of raw and non raw starch digesting amylase degraded both cereal and tuber or root starches significantly. Source of assay starch significantly influenced raw starch digesting activity. Optimum pH for the raw starch degrading and the extracellular amylase were 6.0 and 3.5-4.0, respectively. However, both enzyme activities appeared t o be uninfluenced across a relatively broad pH range 3.0-7.0. N o correlation was found between the capacity of starch to induce expression of the enzyme and its susceptibility to enzyme digestion. The adsorbability of the various starches to raw starch digesting amylase was directly related to their digestibility.

show abstract

Section: Introductionmentioning

confidence: 99%

Production of raw starch digesting amylase by Aspergillus niger grown on native starch sources

Okolo

Ezeogu

1995

J Sci Food Agric

View full text Add to dashboard Cite

show abstract

“…The ability to produce raw starch-hydrolyzing enzymes has been reported only in some microorganisms so far [18,24,25]. From the view of energy utilization and process simplicity, industrial conversion of starch with raw starch-saccharifying amylase is an economically superior alternative to the conventional process which uses pregelatinized starch as a substrate [26][27][28][29].…”

Section: Substrate Specificitymentioning

confidence: 99%

Thermostableα-Amylase and Glucoamylase fromThermomyces lanuginosus F1

Odibo

Ulbrich‐Hofmann

2001

Acta Biotechnol.

View full text Add to dashboard Cite

An α-amylase and a glucoamylase produced by Thermomyces lanuginosus F 1 were separated by ionexchange chromatography on Q-Sepharose fast flow. The enzymes were further purified to electrophoretic homogeneity by chromatography on Sephadex G-100 and Phenyl-Sepharose CL-4B. The molecular weights and isoelectric points of the enzymes were 55,000 Da and pH i 4.0 for α-amylase and 70,000 Da and pH i 4.0 for glucoamylase, respectively. The optimum pH and temperatures for the enzymes were found to be 5.0 and 60°C for α-amylase, and 6.0 and 70°C for glucoamylase, respectively. Both enzymes were maximally stable at pH 4.0 and retained over 80% of their activity between pH 5.0 and 6.0 for 24 h. After incubation at 90°C (1 h), the α-amylase and glucoamylase retained only 6% and 16% of their activity, respectively. The enzymes readily hydrolyzed soluble starch, amylose, amylopectin and glycogen but hydrolyzed pullulan very slowly. Glucoamylase and α-amylase had highest affinity for soluble starch with K M values of 0.80 mg/ml and 0.67 mg/ml, respectively. The α-amylase hydrolyzed raw starch granules with a predominant production of glucose and maltose. The activities of α-amylase and glucoamylase increased in the presence of Mn 2+ , Co 2+ , Ca 2+ , Zn 2+ and Fe 2+ , but were inhibited by guanidine-HCl, urea and disodium EDTA. Both enzymes possess pH and thermal stability characteristics that may be of technological significance.

show abstract

“…The concept of raw starch hydrolysis and the development of enzymes for that purpose are not new (Colonna et al,1987;Ueda and Koba, 1980;Achi and Njoku-Obi, 1992;Okolo et al, 2000). However, application of RSH technology in dry-grind corn ethanol is relatively new.…”

Section: Introductionmentioning

confidence: 97%

Flaking as a corn preparation technique for dry-grind ethanol production using raw starch hydrolysis

Lamsal

Johnson

2012

Journal of Cereal Science

View full text Add to dashboard Cite

Production of a raw starch saccharifying amylase byBacillus alvei grown on different agricultural substrates

Cited by 16 publications

References 3 publications

Production of raw starch digesting amylase by Aspergillus niger grown on native starch sources

Production of raw starch digesting amylase by Aspergillus niger grown on native starch sources

Thermostableα-Amylase and Glucoamylase fromThermomyces lanuginosus F1

Flaking as a corn preparation technique for dry-grind ethanol production using raw starch hydrolysis

Contact Info

Product

Resources

About