Developing a screening pipeline to uncover resilient laccase enzyme candidates for surface-activation of industrial lignins

2021 ◽  
Author(s):  
Anupama Achal Sharan ◽  
Annie Bellemare ◽  
Adrian Tsang ◽  
Elizabeth Edwards ◽  
Emma Master
Keyword(s):  
Surface Activation ◽  
Laccase Enzyme

Platelet Surface Activation Markers after DDAVP Infusion in Healthy Subjects

1995 ◽  
Vol 74 (03) ◽  
pp. 991-992 ◽  
Author(s):  
D A Tsakiris ◽  
W E Haefeli ◽  
L Linder ◽  
B Steiner ◽  
G A Marbet
Keyword(s):  
Healthy Subjects ◽  
Surface Activation ◽  
Activation Markers ◽  
Platelet Surface

A New Tailored UV Based Surface Activation Method for Bonding to Thermoplastics

2019 ◽  
Author(s):  
Sina Chaeichian ◽  
Kaspar Schaerer ◽  
Ruairi O’Kane ◽  
Michael Halbasch
Keyword(s):  
Activation Method ◽  
Surface Activation

The Use of Ultrasound in Bio-Treatment of Jute Yarn with Laccase Enzyme

2019 ◽  
Vol 12 (4) ◽  
pp. 275-286
Author(s):  
Ali A. Zolriasatein
Keyword(s):  
Tensile Strength ◽  
Reaction Times ◽  
Complete Removal ◽  
Jute Fiber ◽  
Light Fastness ◽  
Color Strength ◽  
Yellowness Index ◽  
Laccase Enzyme ◽  
Enzymatic Delignification ◽  
Jute Yarn

Background and Objective: Jute fiber is highly sensitive to the action of light. Significant features of the photochemical changes lose its tensile strength and develop a yellow color. It has been proved that the phenolic structure of lignin is responsible for the yellowing of jute fiber. In order to remove lignin, jute yarns were treated with laccase enzyme in different treatment times and ultrasonic powers. Lower whiteness index and higher yellowness index values were obtained by the laccase-ultrasound system in contrast to conventional laccase treatment. Methods: The laccase enzyme which entered the fibers by applying ultrasound, decreased the tensile strength while the loss in tensile strength was lower at high ultrasound intensities. FT-IR spectrum showed that the band at 1634 cm-1 assigned to lignin completely disappeared after laccase treatment in the presence of ultrasound. The absence of this peak in the laccase-ultrasound treated jute yarn suggests complete removal of lignin. Change in the morphology of fibers was observed by SEM before and after enzymatic delignification. The laccase-ultrasound treated yarns showed a rougher surface and more porosity. On the other hand, it was more effective in fibrillation of the jute fibers than the conventional method. Finally, bio-treated jute yarns were dyed with basic and reactive dyes. Results: The results indicated that at low intensities of ultrasound and relatively long reaction times, lignin can be more effectively removed and dye strength (K/S) increased to a higher extent. Laccase-ultrasound treatment increased the color strength by 33.65% and 23.40% for reactive and basic dyes respectively. Conclusion: In the case of light fastness, the conventional laccase treated yarns provided better protection than laccase-ultrasound treated yarns.

scholarly journals Increasing the Strength of the Glue Line in the Production of Thermally Modified Wood Paneling

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 253
Author(s):  
Ruslan Rushanovich Safin ◽  
Aigul Ravilevna Shaikhutdinova ◽  
Ruslan Khasanshin ◽  
Shamil Mukhametzyanov ◽  
Albina Safina
Keyword(s):  
Wood Products ◽  
Ultraviolet Rays ◽  
Surface Activation ◽  
Wood Block ◽  
Two Stage ◽  
Adhesion Properties ◽  
Wood Processing ◽  
Ultraviolet Treatment ◽  
Thermally Modified Wood ◽  
Modified Wood

This work is devoted to the study of the effect of ultraviolet rays for the surface activation of pine wood thermally modified at temperatures of 180−240 °C in order to increase the surface roughness, enhance the wettability of thermal wood and the adhesive strength of the glue in the production of wood block furniture panels. Studies were carried out to measure the contact angle of wettability of thermally modified wood samples of pine, as a result of which it was determined that the ultraviolet treatment process contributes to an increase in the adhesion properties of the surface layer of thermally modified wood by more than 13% due to the reactivity of ultraviolet rays to oxidize and degrade ligno-containing wood products. At the same time, the most active process of surface activation takes place during 60 min of ultraviolet irradiation of wood with a total irradiation of at least 125 W/cm2. It was revealed that the combined effect of two-stage wood processing, including preliminary volumetric thermal modification followed by surface ultraviolet treatment, causes an increase in the moisture resistance of glued wood products by 24%. So, if the strength of the glue seam when gluing natural wood samples after boiling decreased by 46%, then the samples that underwent two-stage processing showed a decrease only by 22%. In connection with the results obtained, an improved technology for the production of furniture boards for the manufacture of moisture-resistant wood products is proposed.

ZIF‐8 Decorated WO 3 Nanoplates with Robust Surface Activation for the Enhanced Performances in Photocatalytic N 2 Fixation

2021 ◽  
Vol 6 (22) ◽  
pp. 5411-5418
Author(s):  
Fang Xu ◽  
Jialiang Pan ◽  
Bian Li ◽  
Dapeng Wu ◽  
Xinjun Wang ◽  
...  
Keyword(s):  
Surface Activation

scholarly journals Partial purification and biochemical characterization of a new highly acidic NYSO laccase from Alcaligenes faecalis

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Soad A. Abdelgalil ◽  
Ahmad R. Attia ◽  
Reyed M. Reyed ◽  
Nadia A. Soliman
Keyword(s):  
Enzyme Activity ◽  
Sodium Dodecyl ◽  
Alcaligenes Faecalis ◽  
Maximum Activity ◽  
Sodium Oxalate ◽  
Partial Purification ◽  
Bromophenol Blue ◽  
Bromocresol Purple ◽  
Laccase Enzyme

Abstract Background Due to the multitude industrial applications of ligninolytic enzymes, their demands are increasing. Partial purification and intensive characterization of contemporary highly acidic laccase enzyme produced by an Egyptian local isolate designated Alcaligenes faecalis NYSO were studied in the present investigation. Results Alcaligenes faecalis NYSO laccase has been partially purified and intensively biochemically characterized. It was noticed that 40–60% ammonium sulfate saturation showed maximum activity. A protein band with an apparent molecular mass of ~ 50 kDa related to NYSO laccase was identified through SDS-PAGE and zymography. The partially purified enzyme exhibited maximum activity at 55 °C and pH suboptimal (2.5–5.0). Remarkable activation for enzyme activity was recognized after 10-min exposure to temperatures (T) 50, 60, and 70 °C; time elongation caused inactivation, where ~ 50% of activity was lost after a 7-h exposure to 60 °C. Some metal ions Cu2+, Zn2+, Co2+, Ni2+, Mn2+, Cd2+, Cr2+, and Mg2+ caused strong stimulation for enzyme activity, but Fe2+ and Hg2+ reduced the activity. One millimolar of chelating agents [ethylenediamine tetraacetic acid (EDTA), sodium citrate, and sodium oxalate] caused strong activation for enzyme activity. Sodium dodecyl sulfate (SDS), cysteine-HCl, dithiothreitol (DTT), β-mercaptoethanol, thioglycolic acid, and sodium azide caused strong inhibition for NYSO laccase activity even at low concentration. One millimolar of urea, imidazole, kojic acid, phenylmethylsulfonyl fluoride (PMSF), H2O2, and Triton X-100 caused activation. The partially purified NYSO laccase had decolorization activity towards different dyes such as congo red, crystal violet, methylene blue, fast green, basic fuchsin, bromophenol blue, malachite green, bromocresol purple eriochrome black T, and Coomassie Brilliant Blue R-250 with various degree of degradation. Also, it had a vast range of substrate specificity including lignin, but with high affinity towards p-anisidine. Conclusion The promising properties of the newly studied laccase enzyme from Alcaligenes faecalis NYSO strain would support several industries such as textile, food, and paper and open the possibility for commercial use in water treatment. It will also open the door to new applications due to its ligninolytic properties in the near future.

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