Partitioning and purification of α-amylase in aqueous two-phase systems

Schmidt, A.S.; Ventom, Andrew M.; Asenjo, Juan A.

doi:10.1016/0141-0229(94)90076-0

Cited by 140 publications

(68 citation statements)

References 13 publications

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“…The data show that K a and K t both decrease with increasing PEG molecular weight, which agrees with the observations of Schmid et al [2] and Marcos et al [9]. As the degree of PEG polymerization increases, there are fewer hydroxyl groups for the same concentration of PEG, which leads to an increase in hydrophobicity in the PEG-richer upper phase.…”

Section: Effect Of Peg Molecular Weight and Tie Line Length On α-Amylsupporting

confidence: 82%

“…The pI of α-amylase is around five, which is much lower than the effective pH we tested. Therefore, the negative charge of the α-amylase increased as pH increased, resulting in a gradual distribution of the negatively charged α-amylase to the upper phase [2]. However, as the pH was further increased, the total α-amylase recovery from both phases decreased, which could be a reason that the partition coefficient of α-amylase decreased to some extent at higher pH.…”

Section: Effect Of Ph On α-Amylase Purificationmentioning

confidence: 83%

“…Meanwhile, an increase in PEG molecular weight results in less space for proteins to partition into the upper phase. Since α-amylase has a comparatively high surface hydrophobicity, as evaluated by hydrophobic interaction chromatography [2], the size-exclusion effect is suggested to be the main reason for the decrease in the partition coefficients.…”

Section: Effect Of Peg Molecular Weight and Tie Line Length On α-Amylmentioning

confidence: 99%

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Partial purification of ?-amylase from culture supernatant of Bacillus subtilis in aqueous two-phase systems

Zhi

Song

et al. 2004

Bioprocess Biosyst Eng

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A study was made of the partition and purification of α-amylase from a culture supernatant of Bacillus subtilis in the polyethylene glycol (PEG)-citrate aqueous two-phase system (ATPS). Factors that influenced the partition of the protein in this system, including the molecular weight of the PEG, the tie line length of ATPS, the pH value and the sodium chloride concentration, were investigated. Purification of α-amylase was attained with a purification factor (PF) of 1.8 and 90% yield at pH 6.0 in a PEG1000-citrate ATPS with short tie line length. By utilizing the salt-out effect of neutral salt, the purification of α-amylase was further improved to 2.0 of PF and 80% yield in a PEG3350-citrate ATPS with 4% sodium chloride.

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Section: Effect Of Peg Molecular Weight and Tie Line Length On α-Amylsupporting

confidence: 82%

Section: Effect Of Ph On α-Amylase Purificationmentioning

confidence: 83%

Section: Effect Of Peg Molecular Weight and Tie Line Length On α-Amylmentioning

confidence: 99%

See 1 more Smart Citation

Partial purification of ?-amylase from culture supernatant of Bacillus subtilis in aqueous two-phase systems

Zhi

Song

et al. 2004

Bioprocess Biosyst Eng

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“…As general rule, negatively charged proteins prefer the upper PEG-rich phase and positively charged proteins partition to the lower phase (Schmidt et al 1994). As the pH increases above the isoelectric point (pI) of a protein, it becomes negatively charged, its interaction with PEG becomes stronger (Huddleston et al 1991), and the partition coefficient increases.…”

Section: Effect Of Phmentioning

confidence: 99%

Extraction of amylase from fermentation broth in poly (Ethylene Glycol) salt aqueous two-phase system

Bezerra

Borba

Moreira

et al. 2006

Braz. arch. biol. technol.

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“…The increase in the partition coefficient as a function of pH has been observed for other proteins, like α-amylase, taumatin, L-aspartase and fumarase (5,12,20). According to these authors, the negatively charged protein should prefer the top phase of the aqueous two-phase system.…”

Section: Resultsmentioning

confidence: 97%

Infleunce of pH on the partition of glucose-6-phosphate dehydrogenase and hexokinase in aqueous two-phase system

Silva¹,

Pontes²,

Souza³

et al. 2002

Braz. J. Microbiol.

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Glucose-6-phosphate dehydrogenase (G6PDH) and hexokinase (HK) are important enzymes used in biochemical and medical studies and in several analytical methods. Aqueous two-phase system (ATPS) formed by a polymer solution and an electrolyte solution provides a method for the separation and purification of enzymes with several advantages, including biocompatibility and easy scale up of the process. In this work, the effects of different pH values on the storage stability and partitioning behavior (K, partition coefficient) of the enzymes G6PDH and HK from baker's yeast extract were investigated in ATPS. The results, obtained from the 17.5% PEG 400 : 15.0% phosphate system, showed that when the pH was increased from 5.0 to 8.8, the KHK increased 26-fold and the KG6PDH 2.2-fold. In the 20.0% PEG 1500 : 17.5% phosphate system, the KHK and KG6PDH increased 13 and 1.2-fold, when the pH value was increased from 3.8 to 8.8, respectively. This leads to the conclusion that the partition coefficient for both enzymes is favored by high pH values. A statistical analysis of the results was conducted to confirm this conclusion.

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Partitioning and purification of α-amylase in aqueous two-phase systems

Cited by 140 publications

References 13 publications

Partial purification of ?-amylase from culture supernatant of Bacillus subtilis in aqueous two-phase systems

Partial purification of ?-amylase from culture supernatant of Bacillus subtilis in aqueous two-phase systems

Extraction of amylase from fermentation broth in poly (Ethylene Glycol) salt aqueous two-phase system

Infleunce of pH on the partition of glucose-6-phosphate dehydrogenase and hexokinase in aqueous two-phase system

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