scholarly journals Purification and Characterization of an Extracellular Lipase Produced by Aspergillus oryzae ST11 as a Potential Catalyst for an Organic Synthesis

2021 ◽  
Vol 18 (21) ◽  
pp. 45
Author(s):  
Pattarapon Paitaid ◽  
Jirayu Buatong ◽  
Souwalak Phongpaichit ◽  
Aran H-kittikun
Keyword(s):  
Aspergillus Oryzae ◽  
Lipase Activity ◽  
Sodium Dodecyl ◽  
Tween 20 ◽  
Malt Extract ◽  
Extracellular Lipase ◽  
Polar Solvents ◽  
Optimum Activity ◽  
Wide Range ◽  
Aspergillus Sp

The lipase producing Aspergillus sp. ST11 was identified by molecular and morphological methods. The primers ITS1/ITS4 were used for amplifying the ITS region. It showed that the strain was grouped with Aspergillus oryzae and Aspergillus flavus (98 % bootstrap value). The colony morphology of Aspergillus sp. ST11 on malt extract agar and Czapek yeast agar showed a characteristic of A. oryzae. Therefore, it was identified as Aspergillus oryzae ST11. The lipase produced by the strain was purified and characterized. The purification steps involved precipitation with chilled acetone and separation by column chromatography, with HiTrap® Q HP and Toyopearl Butyl-650M, respectively. After purification, the lipase activity was increased 13 fold and with 7.9 % yield. Its molecular mass was 25 kDa. The purified lipase was stable at a pH between 5.0 - 8.0 and had optimum activity at pH 7.5. It was stable at 30 °C and had optimum activity at 37 °C. Its activity was promoted in the presence of Mg2+ but it was greatly decreased in the presence of Co2+, Cu2+, Hg2+ and Zn2+. Surfactants (Triton X-100, Tween-80, Tween-20, arabic gum, and sodium dodecyl sulfate) showed negative effects on lipase activity, while inhibitors (PMSF, EDTA, and β-mercaptoethanol) did not reduce the activity significantly. Polar solvents, such as methanol and ethanol, had much negative effect on lipase activity compared to non-polar solvents, such as hexane and isooctane. The concentrated lipase from A. oryzae ST11 was used to catalyze the transesterification and gave the highest bioconversion (90 %) after 24 h. HIGHLIGHTS Extracellular lipase produced by Aspergillus oryzae ST11 could be applied in many applications which is more flexible compared with the use of whole-cell biocatalysts High stability toward a wide range of pH and temperature obtained from this extracellular lipase The concentrated lipase shows the capability to produce the high biodiesel from natural oil GRAPHICAL ABSTRACT

Purification and Characterization of Thermostable α-Amylase from Soil Bacterium Bacillus sp.

2021 ◽  
Vol 28 ◽  
Author(s):  
Barış Enez
Keyword(s):  
Metal Ions ◽  
Amylase Activity ◽  
Low Cost ◽  
Sodium Dodecyl ◽  
Tween 20 ◽  
Bacillus Sp ◽  
Wide Range ◽  
Bacterium Bacillus ◽  
Triton X

Background: Amylases are used in several industrial and biotechnological sectors, including those producing textiles, detergents, paper and bakery products. Objective: This study aimed to purify an industrially important α-amylase from Bacillus sp. For this purpose, a single and rapid α-amylase purification was performed using the starch affinity method. Methods: Characterization of the purified enzyme was determined by investigating temperature, pH stability, detergents, and metal ions. Results: The purification coefficient of 29.8-fold with a yield of 9.2% was found. The molecular weight of the purified α-amylase was determined to be 53 kDa by SDS-PAGE, and thermostability was confirmed with 100% activity at 30ºC and 40ºC after 1 h. The purified enzyme was stable over a wide range of pH values, with optimum activity at pH 6.0, 7.0 and 8.0 after 2 h. The study also investigated the effects of the metal ions and detergents on the purified amylase and found that Mg2+ and Ca2+ ions were the activators of the enzyme, while Zn2+, Co2+ and Na+ ions decreased the activity. Furthermore, Hg2+ indicated complete inhibition of amylase activity. The detergents Triton X-100 and Tween 20 increased the α-amylase activity, while sodium dodecyl sulfate inhibited the activity. Conclusion: The purified α-amylase obtained from Bacillus sp. is considered to be environmentally friendly, can be processed in a short time, and has a low cost.

scholarly journals Cloning, Expression, and Characterization of Xylanase G2 from Aspergillus oryzae VTCC-F187 in Aspergillus niger VTCC-F017

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Do Thi Tuyen ◽  
Nguyen Tien Cuong ◽  
Nguyen Sy le Thanh ◽  
Nguyen Thi Thao ◽  
Le Thanh Hoang ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Aspergillus Oryzae ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Xylanase Activity ◽  
Tween 80 ◽  
Polymerase Chain Reaction Method ◽  
Tween 20 ◽  
Highly Active

The study focuses on engineering of recombinant Aspergillus niger to produce highly active xylanase. The xylanase G2 encoding gene originating from Aspergillus oryzae VTCC-F187 was cloned, amplified, and inserted into the pAN7.1GluA vector with specific primers possessing BamHI. The recombinant plasmid was introduced into Aspergillus niger VTCC-F017 by chemical methods. The recombinant strain was checked by polymerase chain reaction method and Southern blot. Next, the recombinant protein was expressed and purified by His-tag column. The molecular mass of the purified xylanase G2, as determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), was 21 kDa with a specific activity of 1025 IU/mg towards 0.5% (w/v) of birchwood xylan. The optimal temperature and pH were 55°C and pH 6.5, respectively. The enzyme was stable in a temperature ranges 25–40°C and a pH ranges 5–7. The presence of Tween 80 enhanced xylanase activity. Triton X-100, however, had no impact on the function of the enzyme. The xylanase activity was reduced by Tween 20, SDS, and organic solvents. The enzyme was completely inhibited by Hg2+ and partially by Zn2+, Fe2+, and Ag+, while it was slightly stimulated by K+ and EDTA.

scholarly journals Biochemical and molecular characterization of Alternaria alternata isolates highly resistant to procymidone from broccoli and cabbage

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Bingran Wang ◽  
Tiancheng Lou ◽  
Lingling Wei ◽  
Wenchan Chen ◽  
Longbing Huang ◽  
...  
Keyword(s):  
Alternaria Alternata ◽  
Single Point ◽  
Sodium Dodecyl ◽  
Cross Resistance ◽  
Molecular Characteristics ◽  
Single Point Mutation ◽  
Wide Range ◽  
Significant Difference ◽  
Leaf Blights ◽  
High Level

AbstractAlternaria alternata, a causal agent of leaf blights and spots on a wide range of hosts, has a high risk of developing resistance to fungicides. Procymidone, a dicarboximide fungicide (DCF), has been widely used in controlling Alternaria leaf blights in China for decades. However, the resistance of A. alternata against DCFs has rarely been reported from crucifer plants. A total of 198 A. alternata isolates were collected from commercial fields of broccoli and cabbage during 2018–2019, and their sensitivities to procymidone were determined. Biochemical and molecular characteristics were subsequently compared between the high-level procymidone-resistant (ProHR) and procymidone-sensitive (ProS) isolates, and also between ProHR isolates from broccoli and cabbage. Compared with ProS isolates, the mycelial growth rate, sporulation capacity and virulence of most ProHR isolates were reduced; ProHR isolates displayed an increased sensitivity to osmotic stresses and a reduced sensitivity to sodium dodecyl sulfate (SDS); all ProHR isolates showed a reduced sensitivity to hydrogen peroxide (H2O2) except for the isolate B102. Correlation analysis revealed a positive cross-resistance between procymidone and iprodione, or fludioxonil. When treated with 10 μg/mL of procymidone, both mycelial intracellular glycerol accumulations (MIGAs) and relative expression of AaHK1 in ProS isolates were higher than those in ProHR isolates. Sequence alignment of AaHK1 from ten ProHR isolates demonstrated that five of them possessed a single-point mutation (P94A, V612L, E708K or Q924STOP), and four isolates had an insertion or a deletion in their coding regions. No significant difference in biochemical characteristics was observed among ProHR isolates from two different hosts, though mutations in AaHK1 of the cabbage-originated ProHR isolates were distinct from those of the broccoli-originated ProHR isolates.

scholarly journals Click Chemistry Enabling Covalent and Non-Covalent Modifications of Graphene with (Poly)saccharides

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 142
Author(s):  
Hu Li ◽  
Raffaello Papadakis
Keyword(s):  
Click Chemistry ◽  
Life Science ◽  
Environmental Applications ◽  
Energy Materials ◽  
Sensors And Actuators ◽  
Polar Solvents ◽  
Wide Range ◽  
Potential Applications ◽  
Covalent Modifications

Graphene is a material with outstanding properties and numerous potential applications in a wide range of research and technology areas, spanning from electronics, energy materials, sensors, and actuators to life-science and many more. However, the insolubility and poor dispersibility of graphene are two major problems hampering its use in certain applications. Tethering mono-, di-, or even poly-saccharides on graphene through click-chemistry is gaining more and more attention as a key modification approach leading to new graphene-based materials (GBM) with improved hydrophilicity and substantial dispersibility in polar solvents, e.g., water. The attachment of (poly)saccharides on graphene further renders the final GBMs biocompatible and could open new routes to novel biomedical and environmental applications. In this review, recent modifications of graphene and other carbon rich materials (CRMs) through click chemistry are reviewed.

scholarly journals Mucin biosynthesis. Properties of a bovine tracheal mucin β-6-N-acetylglucosaminyltransferase

1985 ◽  
Vol 227 (2) ◽  
pp. 405-412 ◽  
Author(s):  
P W Cheng ◽  
W E Wingert ◽  
M R Little ◽  
R Wei
Keyword(s):  
Enzyme Activity ◽  
Freezing Point ◽  
Cetylpyridinium Chloride ◽  
Sodium Dodecyl ◽  
Sodium Deoxycholate ◽  
Gas Chromatography Mass Spectrometry ◽  
Tween 20 ◽  
Group A ◽  
Michaelis Constants ◽  
Triton X

We have characterized a bovine tracheal mucin beta-6-N-acetylglucosaminyltransferase that catalyses the transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to the C-6 of the N-acetylgalactosamine residue of galactosyl-β 1→3-N-acetylgalactosamine. Optimal enzyme activity was obtained between pH 7.5-8.5, at 5mM-MnCl2, and at 0.06-0.08% (v/v) Triton X-100 (or Nonidet P-40), or 0.5-5.0% (v/v) Tween 20. Ba2+, Mg2+ and Ca2+ could partially replace Mn2+, but Co2+, Fe2+, Cd2+ and Zn2+ could not. Sodium dodecyl sulphate, cetylpyridinium chloride, sodium deoxycholate, octyl beta-D-glucoside, digitonin and alkyl alcohols were less effective in enhancing enzyme activity, and dimethyl sulphoxide was ineffective. The apparent Michaelis constants were 1.25 mM for UDP-N-acetylglucosamine, 0.94-3.34 mM for freezing-point-depressing glycoprotein and 0.19 mM for periodate-treated blood-group-A porcine submaxillary mucin. Asialo ovine submaxillary mucin could not serve as the glycosyl acceptor. The structure of the 14C-labelled oligosaccharide obtained by alkaline-borohydride treatment of the product was identified as Gal beta 1→3(Glc-NAc beta 1→6)N-acetylgalactosaminitol by beta-hexosaminidase treatment, gas chromatography-mass spectrometry and 1H-n.m.r. (270 MHz) analysis. The enzyme is important in the regulation of mucin oligosaccharide biosynthesis.

Reproducibility and quality assurance of two-dimensional gel electrophoresis of serum specimens.

1982 ◽  
Vol 28 (4) ◽  
pp. 908-914 ◽  
Author(s):  
R P Tracy ◽  
R M Currie ◽  
D S Young
Keyword(s):  
Quality Assurance ◽  
Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Two Dimensional ◽  
Protein Loss ◽  
Serum Samples ◽  
Silver Stain ◽  
Two Dimensional Gel Electrophoresis ◽  
Report Quality ◽  
Wide Range

Abstract Currently we are using two different ISO-DALT two-dimensional gel electrophoresis systems, designated MC-Iso 1 and MC-Iso 2, for the analysis of serum and plasma samples. Here we report quality-assurance data for both of these systems. CV values for the slopes of the pH gradient (ISO dimension) are 5.6% of less; CV values for the slopes of the molecular-mass curves (log Mr vs relative mobility in the DALT dimension) are 3.4% or less. We examined the various steps of the analysis in detail for reproducibility and protein loss, using radiolabeled albumin, alpha 2-macroglobulin, and beta 2-microglobulin. Generally, in the first dimension, less protein enters the MC-Iso 2 gels (our routine system in which silver stain is used) than enters the MC-Iso 1 gels (our wide-range system for myeloma serum samples, in which the gel is stained with Coomassie Blue), on the average, 87% as much. The CV at this stage for both systems is 5--8%. During equilibration, considerable amounts of protein are lost (approximately 30% in 10 min) from the ISO gel, and the reproducibility is also decreased. Resolution in the DALT dimension has, in most cases, little or no effect on either recovery or reproducibility. Overall, for most proteins expected to appear in an ISO gel of a given pH range, approximately 50--60% of the starting material may be expected to reside in the sodium dodecyl sulfate slab gel, under our conditions. The two most important variables affecting recovery are the concentration of the NaOH (used as catholyte) and the pH of the starting sample. The overall CV for the process is between 8 and 12%.

scholarly journals PRODUCTION AND STABILITY OF MYCO-FLOCCULANTS FROM LENTINUS SQUARROSULUS RWF5 AND SIMPLICILLIUM OBCLAVATUM RWF6 FOR REDUCTION OF WATER TURBIDITY

2018 ◽  
Vol 19 (1) ◽  
pp. 48-58
Author(s):  
Nessa X Jebun ◽  
Abdullah Al Mamun ◽  
Md. Zahangir Alam ◽  
Raha Ahmad Raus
Keyword(s):  
Mixed Culture ◽  
Removal Rate ◽  
Production Optimization ◽  
Screening Tests ◽  
Malt Extract ◽  
Water And Wastewater Treatment ◽  
Turbidity Removal ◽  
Single Culture ◽  
Inoculum Dose ◽  
Wide Range

The production and stability of two novel myco-flocculants produced by river water fungus (RWF) were investigated. Screening tests were conducted to find suitable nutrients, pH, nutrient concentration, inoculum dose, and stability for two myco-flocculants L. squarrosulus (RWF5) and S. obclavatum (RWF6). The strains showed good flocculating activity in reducing turbidity of kaolin suspension while malt extract was used as nutrient source. Supernatants of RWF5 and RWF6 were able to reduce turbidity from 900±10 NTU to 46 NTU (95%) and 195 NTU (78%), respectively. In order to enhance the production, optimization of cultivation conditions were studied using a one-factor-at-a-time (OFAT) method. L. squarrosulus (RWF5) reduced 96% of turbidity at optimum conditions, comprising of 0.1% (w/v) malt extract, 3% (v/v) inoculum dose, and initial pH 7.0 for 6 days. The results of the compatible mixed culture showed good flocculation activity at 88% compared to a single culture of S. obclavatum at 78%. On the other hand, L. squarrosulus showed better turbidity reduction in the single culture rather than the mixed culture. The stability of L. squarrosulus and S. obclavatum supernatants showed excellent turbidity reduction over a wide pH range of 4-8 with the maximal flocculation rate of 96% and 90%, respectively, at pH 7.0. They also exhibited high turbidity removal ability in a temperature range of 4 oC – 55 oC for 24h with a maximum turbidity removal rate of 96% (RW5) and 87% (RW6) at 25 oC. Time stability of the L. squarrosulus supernatant showed good turbidity removal potential at above 90% at room temperature (28± 2 oC) and 85% at low temperature (4 oC) for 12 days. The high flocculating rate of the myco-flocculants and their good stability under wide range of temperature indicated their potentiality as biodegradable flocculants for water and wastewater treatment industry. ABSTRAK: Keberhasilan dan kestabilan dua myco-gumpalan baharu oleh kulat air sungai (RWF) telah dikaji. Ujian penapisan telah dijalankan untuk mencari nutrien sesuai, pH, kepekatan nutrien, dos inokulum dan kestabilan dua myco-gumpalan L. squarrosulus (RWF5) dan S. obclavatum (RWF6). Rantaian menunjukkan aktiviti gumpalan yang baik dalam mengurangkan kekeruhan air sungai dengan penggantungan koalin di mana ekstrak malt telah digunakan sebagai sumber nutrien. Larutan supernatan RWF5 dan RWF6, masing-masing mampu mengurangkan kekeruhan dari 900±10 NTU kepada 46 NTU (95%) dan 195 NTU (78%). Bagi meningkatkan pengeluaran, keadaan optimum bagi menggalakkan hasil telah diselidiki menggunakan kaedah Satu Faktor pada Tiap Masa (OFAT). Pada takat optimum, L. squarrosulus (RWF5) mengurangkan 96% kekeruhan, ianya terdiri daripada ekstrak malt 0.1% (w/v), dos inokulum 3% (v/v) dan pH awal 7.0 selama 6 hari. Keputusan kultur campuran yang sesuai menunjukkan aktiviti penggumpalan yang baik pada 88% berbanding kultur sendirian S. obclavatum pada 78%. Pada waktu sama, L. squarrosulus menunjukkan pengurangan kekeruhan yang lebih baik dalam kultur sendirian berbanding kultur campuran. Kestabilan larutan supernatan L. squarrosulus dan S. obclavatum menunjukkan pengurangan kekeruhan yang sangat baik pada pH yang luas iaitu 4-8 dengan kadar maksimum kekeruhan pada 96% dan 90%, pada pH 7.0 masing-masing. Keduanya menunjukkan kebolehan penyingkiran kekeruhan yang tinggi pada skala suhu 4 oC – 55 oC selama 24 jam dengan kadar nyah kekeruhan maksimum pada 96% (RW5) dan 87% (RW6) pada suhu 25 oC. Kestabilan masa larutan supernatan L. Squarrosulus menunjukkan potensi penyingkiran kekeruhan terbaik atas 90% pada suhu bilik (28± 2 oC) dan 85% pada suhu rendah (4 oC) selama 12 hari. Kadar gumpalan yang tinggi oleh myro-gumpalan dan kestabilan yang baik pada julat suhu yang luas menunjukkan potensinya sebagai agen biodegradasi gumpalan kepada air dan industri rawatan loji air.

scholarly journals The Effect Ultrasound and Surfactants on Nanobubbles Efficacy against Listeria innocua and Escherichia coli O157:H7, in Cell Suspension and on Fresh Produce Surfaces

Foods ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2154
Author(s):  
Shamil Rafeeq ◽  
Reza Ovissipour
Keyword(s):  
Escherichia Coli ◽  
Cell Suspension ◽  
Sodium Dodecyl ◽  
Listeria Innocua ◽  
Wash Water ◽  
Tween 20 ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Bacterial Removal ◽  
The Impact

Removing foodborne pathogens from food surfaces and inactivating them in wash water are critical steps for reducing the number of foodborne illnesses. In this study we evaluated the impact of surfactants on enhancing nanobubbles’ efficacy on Escherichia coli O157:H7, and Listeria innocua removal from spinach leaves. We evaluated the synergistic impact of nanobubbles and ultrasound on these two pathogens inactivation in the cell suspension. The results indicated that nanobubbles or ultrasound alone could not significantly reduce bacteria in cell suspension after 15 min. However, a combination of nanobubbles and ultrasonication caused more than 6 log cfu/mL reduction after 15 min, and 7 log cfu/mL reduction after 10 min of L. innocua and E. coli, respectively. Nanobubbles also enhanced bacterial removal from spinach surface in combination with ultrasonication. Nanobubbles with ultrasound removed more than 2 and 4 log cfu/cm2 of L. innocua and E. coli, respectively, while ultrasound alone caused 0.5 and 1 log cfu/cm2 of L. innocua and E. coli reduction, respectively. No reduction was observed in the solutions with PBS and nanobubbles. Adding food-grade surfactants (0.1% Sodium dodecyl sulfate-SDS, and 0.1% Tween 20), did not significantly enhance nanobubbles efficacy on bacterial removal from spinach surface.

Sign in / Sign up

Export Citation Format

Share Document