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1.
《中国化学会会志》2018,65(6):771-779
Inulin hydrolysis was performed by inulinase from Aspergillus niger covalently immobilized on magnetite nanoparticles (Fe3O4) covered with soy protein isolate (Fe3O4/SPI) functionalized by bovine serum albumin (Fe3O4/SPI/BSA) nanoparticles as a new bio‐functional carrier. The specific activity and protein content of the immobilized enzyme were 25.99 U/mg and 3.52 mg/mL, respectively, with 80% enzyme loading. The immobilized inulinase showed maximum activity at 45 °C, which is 5 °C higher than the optimum temperature of the free enzyme. Also, the optimum pH of the immobilized enzyme shifted from 6 to 5.5, which is more acidic compared to that of the free enzyme. The Km value of immobilized inulinase decreased to 2.03 mg/mL. Thermal stability increased considerably at 65 and 75 °C, and a 5.13‐fold rise was detected in the enzyme half‐life at 75 °C after immobilization. Moreover, 80% of initial activity of immobilized inulinase remained after 10 cycles of hydrolysis. 相似文献
2.
Candida kefyr DSM 70106 was cultivated in a medium containing inulin as a carbon source. About 92% of the inulinase was recovered directly
from the medium. Different concentration (Cf) and enrichment (Ef) factors were obtained, using the following methods: Cross-flow filtration (microfiltration and cell diafiltration were carried
out using a rotary filter; enzyme ultrafiltration and diafiltration were performed using a cassette module): Cf = 7.5 and Ef = 2.2; liquid-liquid extraction ofN-Benzyl-N-Dodecyl-N-bis[2-hydroxyethyl] ammonium chloride (BDBAC) reversed micelles: Cf = 2.5 and Ef = 2.7; and expanded-bed adsorption: Cf = 2.8 and Ef = 4.3. 相似文献
3.
The extracellular inulinase in the supernatant of the cell culture of the marine yeast Cryptococcus aureus G7a was purified to homogeneity with a 7.2-fold increase in specific inulinase activity compared to that in the supernatant
by ultrafiltration, concentration, gel filtration chromatography (Sephadex™ G-75), and anion exchange chromatography (DEAE
sepharose fast flow anion exchange). The molecular mass of the purified enzyme was estimated to be 60.0 kDa. The optimal pH
and temperature of the purified enzyme were 5.0 and 50 °C, respectively. The enzyme was activated by Ca2+, K+, Na+, Fe2+, and Zn2+. However, Mg2+, Hg2+, and Ag+ acted as inhibitors in decreasing the activity of the purified inulinase. The enzyme was strongly inhibited by phenylmethanesulphonyl
fluoride (PMSF), iodoacetic acid, EDTA, and 1,10-phenanthroline. The K
m and V
max values of the purified enzyme for inulin were 20.06 mg/ml and 0.0085 mg/min, respectively. A large amount of monosaccharides
were detected after the hydrolysis of inulin with the purified inulinase, indicating the purified inulinase had a high exoinulinase
activity. 相似文献
4.
《Journal of carbohydrate chemistry》2013,32(2-3):163-168
Abstract By enzymatic reaction of sucrose (1) and isomelezitose (2) with the enzyme inulinase (NOVO, SP230) a novel tetrasaccharide (3) was synthesised,.the molecular weight of which was confirmed by electrospray‐ionisation mass spectrometry and gel permeation chromatography. Its structure was established by acid hydrolysis as well as 1H and 13C NMR spectroscopy to be sucrosyl‐(1 → 2)‐β‐isomaltulose 3 (α‐D‐glucopyranosyl‐(1 → 2)‐β‐D‐fructofuranosyl‐(1 → 2)‐β‐D‐fructofuranosyl‐(6 → 1)‐α‐D‐glucopyranoside). 相似文献
5.
Ashok Pandey Simon Joseph L. Ashakumary P. Selvakumar Carlos R. Soccol 《Applied biochemistry and biotechnology》1999,82(2):103-114
A newly isolated mesophilic bacterial strain from dahlia rhizosphere, identified as Staphylococcus sp. and designated as RRL-M-5, was evaluated for inulinase synthesis in submerged cultivation using different carbon sources
individually or in combination with inulin as substrate. Inulin appeared as the most favorable substrate at a 0.5–1.0% concentration.
Media pH influenced the enzyme synthesis by the bacterial strain, which showed an optimum pH at 7.0–7.5. Supplementation of
fermentation medium with external nitrogen (organic and inorganic) showed a mixed impact on bacterial activity of enzyme synthesis.
The addition of soybean meal and corn steep solid resulted in about an 11% increase in enzyme titers. Among inorganic nitrogen
sources, ammonium sulfate was found to be the most suitable. Maximum enzyme activities (446 U/L) were obtained when fermentation
was carried out at 30°C for 24 h with a medium containing 0.5% inulin as a sole carbon source and 0.5% soybean meal as the
nitrogen source. Bacterial inulinase could be a good source for the hydrolysis of inulin for the production of d-fructose. 相似文献
6.
Optimization of inulinase production by Kluyveromyces marxianus using factorial design 总被引:4,自引:0,他引:4
Factorial design and response surface techniques were used to optimize the culture medium for the production of inulinase
by Kluyveromyces marxianus. Sucrose was used as the carbon source instead of inulin. Initially, a fractional factorial design (25–1) was used in order to determine the most relevant variables for enzyme production. Five parameters were studied (sucrose,
peptone, yeast extract, pH, and K2HPO4), and all were shown to be significant. Sucrose concentration and pH had negative effects on inulinase production, whereas
peptone, yeast extract, and K2HPO4 had positive ones. The pH was shown to be the most significant variable and should be preferentially maintained at 3.5. According
to the results from the first factorial design, sucrose, peptone, and yeast extract concentrations were selected to be utilized
in a full factorial design. The optimum conditions for a higher enzymatic activity were then determined: 14 g/L of sucrose,
10 g/L of yeast extract, 20 g/L of peptone, 1 g/L of K2HPO4. The enzymatic activity in the culture conditions was 127 U/mL, about six times higher than before the optimization. 相似文献
7.
Characterization of Thermo-stable Endoinulinase from a New Strain <Emphasis Type="Italic">Bacillus Smithii</Emphasis> T7 总被引:1,自引:0,他引:1
A new thermophilic inulinase-producing strain, which grows optimally at 60 °C, was isolated from soil samples with medium
containing inulin as a sole carbon source. It was identified as a Bacillus smithii by analysis of 16s rDNA. Maximum inulinase yield of 135.2 IU/ml was achieved with medium pH7.0, containing inulin 2.0%, (NH4)H2PO4 0.5%, yeast extract 0.5%, at 50 °C 200 rpm shaker for 72-h incubation. The purified inulinase from the extracellular extract
of B. smithii T7 shows endoinulinolytic activity. The optimum pH for this endoinulinase is 4.5 and stable at pH range of 4.0–8.0. The optimum
temperature for enzyme activity was 70 °C, the half life of the endoinulinase is 9 h and 2.5 h at 70 °C and 80 °C respectively.
Comparatively lower Michaelis–Menten constant (4.17 mM) and higher maximum reaction velocity (833 IU/mg protein) demonstrate
the endoinulinase’s greater affinity for inulin substrate. These findings are significant for its potential industrial application. 相似文献
8.
João Paulo Bender Marcio Antônio Mazutti Débora de Oliveira Marco Di Luccio Helen Treichel 《Applied biochemistry and biotechnology》2006,132(1-3):951-958
Inulinase is an enzyme relevant to fructose production by enzymatic hydrolysis of inulin. This enzyme is also applied in the
production of fructo-oligosaccharides that may be used as a new food functional ingredient. Commercial inulinase is currently
obtained using inulin as substrate, which is a relatively expensive raw material. In Brazil, the production of this enzyme
using residues of sugarcane and corn industry (sugarcane bagasse, molasses, and corn steep liquor) is economically attractive,
owing to the high amount and low cost of such residues. In this context, the aim of this work was the assessment of inulinase
production by solid state fermentation using by Kluyveromyces marxianus NRRL Y-7571. The solid medium consisted of sugar cane bagasse supplemented with molasses and corn steep liquor. The production
of inulinase was carried out using experimental design technique. The effect of temperature, moisture, and supplements content
were investigated. The enzymatic activity reached a maximum of 445 units of inulinase per gram of dry substrate. 相似文献
9.
Bender JP Mazutti MA Di Luccio M Treichel H 《Applied biochemistry and biotechnology》2008,149(3):195-203
Production of inulinase by solid state fermentation always involves an extraction step, which dictates enzyme recovery yield and is related to cultivation conditions and control of process parameters. This work is focused on the study of extraction conditions aiming to maximize yield of an inulinase obtained by solid state fermentation of sugar cane bagasse and Kluyveromyces marxianus NRRL Y-7571. Kinetics of extraction was followed varying the kind of solvent used. After determining the best solvent, an experimental design was carried out to study the effect of the solid/liquid ratio (1:10-1:20), extraction temperature (20-53 degrees C), and stirring rate (50-177 rpm). Results showed that maximum yield was obtained when sodium acetate buffer 0.1 M pH 4.8 was used, using a solid/liquid ratio of 1:10, at 53 degrees C and 150 rpm for 40 min. 相似文献
10.
Caroline Costa Moraes Marcio A. Mazutti Maria Isabel Rodrigues Francisco Maugeri Filho Susana Juliano Kalil 《Journal of chromatography. A》2009,1216(20):4395-4401
A mathematical model for an expanded bed column was developed to predict breakthrough curves for inulinase adsorption on Streamline SP ion-exchange adsorbent, using a crude fermentative broth with cells as the feedstock. The kinetics and mass transfer parameters were estimated using the PSO (particle swarm optimization) heuristic algorithm. The parameters were estimated for each expansion degree (ED) using three breakthrough curves at initial inulinase concentrations of 65.6 U mL−1. In sequence, the model parameters for an ED of 2.5 were validated using the breakthrough curve at an initial concentration of 114.4 U mL−1. The applicability of the validated model in process optimization was investigated, using the model as a process simulator and experimental design methodology to optimize the column and process efficiencies. The results demonstrated the usefulness of this methodology for expanded bed adsorption processes. 相似文献