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Ghanem, Essam; Al-Sayed, Hashim; Saleh, Kareema M.

doi:10.1023/a:1008947620734

Cited by 65 publications

(8 citation statements)

References 26 publications

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“…3) was found at pH .0. This finding agrees with results reported for other plant lipases that display pH optima at alkaline values [3,8,19,20] and is also consistent with the pH optima reported for lipases from other sources [1,16,21,22]. Effect of Oxidizing, Reducing, and Chelating Agents on Lipase Activity…”

Section: Effect Of Temperature and Phsupporting

confidence: 92%

A New Lipase Isolated from Oleaginous Seeds from Pachira aquatica (Bombacaceae)

Polizelli

Facchini

Cabral

et al. 2008

Appl Biochem Biotechnol

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A new lipase from seeds of Pachira aquatica was purified to homogeneity by SDS-PAGE obtaining an enzyme with a molecular weight of approximately 55 kDa. The purified lipase exhibited maximum activity at 40 degrees C and pH 8.0, for an incubation time of 90 min. Concerning temperature stability, at the range from 4 to 50 degrees C, it retained approximately 47% of its original activity for 3 h. The enzyme activity increased in the presence of Ca(++) and Mg(++), but was inhibited by Hg(++), Mn(++), Zn(++), Al(+++) and various oxidizing and reducing agents. The lipase was highly stable in the presence of organic solvents, and its activity was stimulated by methanol. The values of K(m) and V(max) were 1.65 mM and 37.3 micromol mL(-1) min(-1), respectively, using p-nitrophenylacetate as substrate. The enzyme showed preference for esters of long-chain fatty acids, but demonstrated significant activity against a wide range of substrates.

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Section: Effect Of Temperature and Phsupporting

confidence: 92%

A New Lipase Isolated from Oleaginous Seeds from Pachira aquatica (Bombacaceae)

Polizelli

Facchini

Cabral

et al. 2008

Appl Biochem Biotechnol

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“…32 The positive influence of calcium has been observed by many researchers, e.g. Ghanem et al, 27 who reported an increase of 150% in lipase activity in the presence of 50 mM Ca 2+ , and Yu et al, 33 who reported a 4-fold increase in lipase activity using 2 µmol L -1 Ca 2+ . However, in both these cases the enzyme's thermostability was not good.…”

Section: Effect Of Ca 2+ On Activity and Stabilitymentioning

confidence: 89%

“…There are also some reports on the optimal pH (10.0) for lipases from generous Bacillus. 27 With regard to the effect of temperature on lipase activity, for most cases, optimal activity has been found between 30 and 65 ºC 23,28 or in some cases, at higher temperatures of 75 ºC. 9 Thermal tolerant lipases are very promising for industrial applications, since processes performed at high temperatures increase the reaction rate, for example in detergent formulations and other biotransformations.…”

Section: Effect Of Ph and Temperature On Activity And Stabilitymentioning

confidence: 99%

Biochemical characterisation of lipase from a new strain of Bacillus sp. ITP-001

et al. 2012

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Recebido em 26/9/11; aceito em 24/1/12; publicado na web em 15/5/12Lipases are characterised mainly by catalytic versatility and application in different industrial segments. The aim of this study was to biochemically characterise a lipase from a new strain of Bacillus sp. ITP-001. The isoelectric point and molecular mass were 3.12 and 54 kDa, respectively. The optima lipase activity was 276 U g -1 at pH 7.0 and a temperature of 80 °C, showing greater stability at pH 5.0 and 37 °C. , respectively determined by the Eadie-Scatchard method.

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“…Among all biocatalytic processes, lipase reactions have many advantages owing to their high regioselectivity and mild incubation conditions, and maximize the efficiency of trivial processes in comparison to chemical methods [5][6][7]. Recently, it was reported that lipase can serve as a catalyst to regioselectively produce chloramphenicol derivatives.…”

Section: Introductionmentioning

confidence: 99%

Immobilization of a Novel ESTBAS Esterase from Bacillus altitudinis onto an Epoxy Resin: Characterization and Regioselective Synthesis of Chloramphenicol Palmitate

et al. 2019

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Novel gene estBAS from Bacillus altitudinis, encoding a 216-amino acid esterase (EstBAS) with a signal peptide (SP), was expressed in Escherichia coli. EstBASΔSP showed the highest activity toward p-nitrophenyl hexanoate at 50 °C and pH 8.0 and had a half-life (T1/2) of 6 h at 50 °C. EstBASΔSP was immobilized onto a novel epoxy resin (Lx-105s) with a high loading of 96 mg/g. Fourier transform infrared (FTIR) spectroscopy showed that EstBASΔSP was successfully immobilized onto Lx-105s. In addition, immobilization improved its enzymatic performance by widening the tolerable ranges of pH and temperature. The optimum temperature of immobilized EstBASΔSP (Lx-EstBASΔSP) was higher, 60 °C, and overall thermostability improved. T1/2 of Lx-EstBASΔSP and free EstBASΔSP at 60 °C was 105 and 28 min, respectively. Lx-EstBASΔSP was used as a biocatalyst to synthesize chloramphenicol palmitate by regioselective modification at the primary hydroxyl group. Conversion efficiency reached 94.7% at 0.15 M substrate concentration after 24 h. Lx-EstBASΔSP was stable and could be reused for seven cycles, after which it retained over 80% of the original activity.

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Cited by 65 publications

References 26 publications

A New Lipase Isolated from Oleaginous Seeds from Pachira aquatica (Bombacaceae)

A New Lipase Isolated from Oleaginous Seeds from Pachira aquatica (Bombacaceae)

Biochemical characterisation of lipase from a new strain of Bacillus sp. ITP-001

Immobilization of a Novel ESTBAS Esterase from Bacillus altitudinis onto an Epoxy Resin: Characterization and Regioselective Synthesis of Chloramphenicol Palmitate

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