Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria

Oghenetega Jonathan Avwioroko; Nyerhovwo John Tonukari; Samuel Ogheneovo Asagba

doi:doi:10.11648/j.ab.20150301.14

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Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria

Oghenetega Jonathan Avwioroko, Nyerhovwo John Tonukari, Samuel Ogheneovo Asagba

Published in Advances in Biochemistry (Volume 3, Issue 1)

Received: 22 January 2015 Accepted: 1 February 2015 Published: 9 February 2015

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Abstract

In this research, crude α-amylases associated with the spoilage of cassava (Manihot esculenta) tubers/ product (‘eba’) were biochemically characterized. They were isolated from five fungi: Aspergillus sp. CSA25, Aspergillus sp. CSA26, Aspergillus sp. CSA27, Aspergillus sp. CSA35 and Aspergillus sp. CSA38. The results of the analyses showed that the activities of α-amylase obtained from both sources (cassava tuber/ eba) were optimal at 45°C and pH 5.0. The maximum specific activity (Vmax) of the enzyme was found to be 10 U/mg protein, while its Michaelis-Menten constant (Km) was between 0.37 -1.25%w/v. The α-amylase is thermally stable for 1 - 2 h at optimum temperature and pH (45°C; pH 5.0). A broad range of substrate specificity was expressed by the enzyme for cassava starch-containing products (tapioca flour, garri flour, cassava flour, 1%, w/v); however, potato (Ipomoea batatas) starch, yam (Dioscorea rotundata) flour and cocoyam (Colocasia esculenta) flour were relatively minimally hydrolyzed by the crude α-amylases obtained from Aspergillus spp. that caused spoilage of cassava. Ethylenediamine tetraacetic acid (1 mM EDTA) and Mg2+ treatment had no significant (p > 0.05) effect on the activities of the amylase, but Na+, K+, Ca2+, Fe3+, thiourea and 5′,5′-dithiobis-2-nitrobenzoate (1 mM DTNB) enhanced its activities. The fungal α-amylases were most activated by K+ and had a salt tolerance of 1 - 2 M NaCl for 24 h. The fungal α-amylases reported in this study would find useful application in industries like food industry, detergent industry, paper industry, textile industry, pharmaceutical industry, etc where microbial α-amylases would be required for efficient and cost-effective hydrolysis of cassava starch, cassava flour and or its products.

Published in	Advances in Biochemistry (Volume 3, Issue 1)
DOI	10.11648/j.ab.20150301.14
Page(s)	15-23
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2015. Published by Science Publishing Group

Keywords

Manihot esculenta (Cassava), Aspergillus spp., α-Amylase, Biochemical Characterization

References

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Oghenetega Jonathan Avwioroko, Nyerhovwo John Tonukari, Samuel Ogheneovo Asagba. (2015). Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria. Advances in Biochemistry, 3(1), 15-23. https://doi.org/10.11648/j.ab.20150301.14

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Oghenetega Jonathan Avwioroko; Nyerhovwo John Tonukari; Samuel Ogheneovo Asagba. Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria. Adv. Biochem. 2015, 3(1), 15-23. doi: 10.11648/j.ab.20150301.14

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AMA Style

Oghenetega Jonathan Avwioroko, Nyerhovwo John Tonukari, Samuel Ogheneovo Asagba. Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria. Adv Biochem. 2015;3(1):15-23. doi: 10.11648/j.ab.20150301.14

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@article{10.11648/j.ab.20150301.14,
  author = {Oghenetega Jonathan Avwioroko and Nyerhovwo John Tonukari and Samuel Ogheneovo Asagba},
  title = {Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria},
  journal = {Advances in Biochemistry},
  volume = {3},
  number = {1},
  pages = {15-23},
  doi = {10.11648/j.ab.20150301.14},
  url = {https://doi.org/10.11648/j.ab.20150301.14},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ab.20150301.14},
  abstract = {In this research, crude α-amylases associated with the spoilage of cassava (Manihot esculenta) tubers/ product (‘eba’) were biochemically characterized. They were isolated from five fungi: Aspergillus sp. CSA25, Aspergillus sp. CSA26, Aspergillus sp. CSA27, Aspergillus sp. CSA35 and Aspergillus sp. CSA38. The results of the analyses showed that the activities of α-amylase obtained from both sources (cassava tuber/ eba) were optimal at 45°C and pH 5.0. The maximum specific activity (Vmax) of the enzyme was found to be 10 U/mg protein, while its Michaelis-Menten constant (Km) was between 0.37 -1.25%w/v. The α-amylase is thermally stable for 1 - 2 h at optimum temperature and pH (45°C; pH 5.0). A broad range of substrate specificity was expressed by the enzyme for cassava starch-containing products (tapioca flour, garri flour, cassava flour, 1%, w/v); however, potato (Ipomoea batatas) starch, yam (Dioscorea rotundata) flour and cocoyam (Colocasia esculenta) flour were relatively minimally hydrolyzed by the crude α-amylases obtained from Aspergillus spp. that caused spoilage of cassava. Ethylenediamine tetraacetic acid (1 mM EDTA) and Mg2+ treatment had no significant (p > 0.05) effect on the activities of the amylase, but Na+, K+, Ca2+, Fe3+, thiourea and 5′,5′-dithiobis-2-nitrobenzoate (1 mM DTNB) enhanced its activities. The fungal α-amylases were most activated by K+ and had a salt tolerance of 1 - 2 M NaCl for 24 h. The fungal α-amylases reported in this study would find useful application in industries like food industry, detergent industry, paper industry, textile industry, pharmaceutical industry, etc where microbial α-amylases would be required for efficient and cost-effective hydrolysis of cassava starch, cassava flour and or its products.},
 year = {2015}
}

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TY  - JOUR
T1  - Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria
AU  - Oghenetega Jonathan Avwioroko
AU  - Nyerhovwo John Tonukari
AU  - Samuel Ogheneovo Asagba
Y1  - 2015/02/09
PY  - 2015
N1  - https://doi.org/10.11648/j.ab.20150301.14
DO  - 10.11648/j.ab.20150301.14
T2  - Advances in Biochemistry
JF  - Advances in Biochemistry
JO  - Advances in Biochemistry
SP  - 15
EP  - 23
PB  - Science Publishing Group
SN  - 2329-0862
UR  - https://doi.org/10.11648/j.ab.20150301.14
AB  - In this research, crude α-amylases associated with the spoilage of cassava (Manihot esculenta) tubers/ product (‘eba’) were biochemically characterized. They were isolated from five fungi: Aspergillus sp. CSA25, Aspergillus sp. CSA26, Aspergillus sp. CSA27, Aspergillus sp. CSA35 and Aspergillus sp. CSA38. The results of the analyses showed that the activities of α-amylase obtained from both sources (cassava tuber/ eba) were optimal at 45°C and pH 5.0. The maximum specific activity (Vmax) of the enzyme was found to be 10 U/mg protein, while its Michaelis-Menten constant (Km) was between 0.37 -1.25%w/v. The α-amylase is thermally stable for 1 - 2 h at optimum temperature and pH (45°C; pH 5.0). A broad range of substrate specificity was expressed by the enzyme for cassava starch-containing products (tapioca flour, garri flour, cassava flour, 1%, w/v); however, potato (Ipomoea batatas) starch, yam (Dioscorea rotundata) flour and cocoyam (Colocasia esculenta) flour were relatively minimally hydrolyzed by the crude α-amylases obtained from Aspergillus spp. that caused spoilage of cassava. Ethylenediamine tetraacetic acid (1 mM EDTA) and Mg2+ treatment had no significant (p > 0.05) effect on the activities of the amylase, but Na+, K+, Ca2+, Fe3+, thiourea and 5′,5′-dithiobis-2-nitrobenzoate (1 mM DTNB) enhanced its activities. The fungal α-amylases were most activated by K+ and had a salt tolerance of 1 - 2 M NaCl for 24 h. The fungal α-amylases reported in this study would find useful application in industries like food industry, detergent industry, paper industry, textile industry, pharmaceutical industry, etc where microbial α-amylases would be required for efficient and cost-effective hydrolysis of cassava starch, cassava flour and or its products.
VL  - 3
IS  - 1
ER  -

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Oghenetega Jonathan Avwioroko

Department of Biochemistry, Faculty of Science, Delta State University, Abraka, Nigeria
Nyerhovwo John Tonukari

Department of Biochemistry, Faculty of Science, Delta State University, Abraka, Nigeria
Samuel Ogheneovo Asagba

Department of Biochemistry, Faculty of Science, Delta State University, Abraka, Nigeria

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Oghenetega Jonathan Avwioroko, Nyerhovwo John Tonukari, Samuel Ogheneovo Asagba. (2015). Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria. Advances in Biochemistry, 3(1), 15-23. https://doi.org/10.11648/j.ab.20150301.14

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ACS Style

Oghenetega Jonathan Avwioroko; Nyerhovwo John Tonukari; Samuel Ogheneovo Asagba. Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria. Adv. Biochem. 2015, 3(1), 15-23. doi: 10.11648/j.ab.20150301.14

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AMA Style

Oghenetega Jonathan Avwioroko, Nyerhovwo John Tonukari, Samuel Ogheneovo Asagba. Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria. Adv Biochem. 2015;3(1):15-23. doi: 10.11648/j.ab.20150301.14

Copy | Download

@article{10.11648/j.ab.20150301.14,
  author = {Oghenetega Jonathan Avwioroko and Nyerhovwo John Tonukari and Samuel Ogheneovo Asagba},
  title = {Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria},
  journal = {Advances in Biochemistry},
  volume = {3},
  number = {1},
  pages = {15-23},
  doi = {10.11648/j.ab.20150301.14},
  url = {https://doi.org/10.11648/j.ab.20150301.14},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ab.20150301.14},
  abstract = {In this research, crude α-amylases associated with the spoilage of cassava (Manihot esculenta) tubers/ product (‘eba’) were biochemically characterized. They were isolated from five fungi: Aspergillus sp. CSA25, Aspergillus sp. CSA26, Aspergillus sp. CSA27, Aspergillus sp. CSA35 and Aspergillus sp. CSA38. The results of the analyses showed that the activities of α-amylase obtained from both sources (cassava tuber/ eba) were optimal at 45°C and pH 5.0. The maximum specific activity (Vmax) of the enzyme was found to be 10 U/mg protein, while its Michaelis-Menten constant (Km) was between 0.37 -1.25%w/v. The α-amylase is thermally stable for 1 - 2 h at optimum temperature and pH (45°C; pH 5.0). A broad range of substrate specificity was expressed by the enzyme for cassava starch-containing products (tapioca flour, garri flour, cassava flour, 1%, w/v); however, potato (Ipomoea batatas) starch, yam (Dioscorea rotundata) flour and cocoyam (Colocasia esculenta) flour were relatively minimally hydrolyzed by the crude α-amylases obtained from Aspergillus spp. that caused spoilage of cassava. Ethylenediamine tetraacetic acid (1 mM EDTA) and Mg2+ treatment had no significant (p > 0.05) effect on the activities of the amylase, but Na+, K+, Ca2+, Fe3+, thiourea and 5′,5′-dithiobis-2-nitrobenzoate (1 mM DTNB) enhanced its activities. The fungal α-amylases were most activated by K+ and had a salt tolerance of 1 - 2 M NaCl for 24 h. The fungal α-amylases reported in this study would find useful application in industries like food industry, detergent industry, paper industry, textile industry, pharmaceutical industry, etc where microbial α-amylases would be required for efficient and cost-effective hydrolysis of cassava starch, cassava flour and or its products.},
 year = {2015}
}

Copy | Download

TY  - JOUR
T1  - Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria
AU  - Oghenetega Jonathan Avwioroko
AU  - Nyerhovwo John Tonukari
AU  - Samuel Ogheneovo Asagba
Y1  - 2015/02/09
PY  - 2015
N1  - https://doi.org/10.11648/j.ab.20150301.14
DO  - 10.11648/j.ab.20150301.14
T2  - Advances in Biochemistry
JF  - Advances in Biochemistry
JO  - Advances in Biochemistry
SP  - 15
EP  - 23
PB  - Science Publishing Group
SN  - 2329-0862
UR  - https://doi.org/10.11648/j.ab.20150301.14
AB  - In this research, crude α-amylases associated with the spoilage of cassava (Manihot esculenta) tubers/ product (‘eba’) were biochemically characterized. They were isolated from five fungi: Aspergillus sp. CSA25, Aspergillus sp. CSA26, Aspergillus sp. CSA27, Aspergillus sp. CSA35 and Aspergillus sp. CSA38. The results of the analyses showed that the activities of α-amylase obtained from both sources (cassava tuber/ eba) were optimal at 45°C and pH 5.0. The maximum specific activity (Vmax) of the enzyme was found to be 10 U/mg protein, while its Michaelis-Menten constant (Km) was between 0.37 -1.25%w/v. The α-amylase is thermally stable for 1 - 2 h at optimum temperature and pH (45°C; pH 5.0). A broad range of substrate specificity was expressed by the enzyme for cassava starch-containing products (tapioca flour, garri flour, cassava flour, 1%, w/v); however, potato (Ipomoea batatas) starch, yam (Dioscorea rotundata) flour and cocoyam (Colocasia esculenta) flour were relatively minimally hydrolyzed by the crude α-amylases obtained from Aspergillus spp. that caused spoilage of cassava. Ethylenediamine tetraacetic acid (1 mM EDTA) and Mg2+ treatment had no significant (p > 0.05) effect on the activities of the amylase, but Na+, K+, Ca2+, Fe3+, thiourea and 5′,5′-dithiobis-2-nitrobenzoate (1 mM DTNB) enhanced its activities. The fungal α-amylases were most activated by K+ and had a salt tolerance of 1 - 2 M NaCl for 24 h. The fungal α-amylases reported in this study would find useful application in industries like food industry, detergent industry, paper industry, textile industry, pharmaceutical industry, etc where microbial α-amylases would be required for efficient and cost-effective hydrolysis of cassava starch, cassava flour and or its products.
VL  - 3
IS  - 1
ER  -

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