Laccase activity measurement by FTIR spectral fingerprinting

2019 ◽  
Vol 122 ◽  
pp. 64-73 ◽  
Author(s):  
Valentina Perna ◽  
Andreas Baum ◽  
Heidi A. Ernst ◽  
Jane W. Agger ◽  
Anne S. Meyer
1983 ◽  
Vol 50 (02) ◽  
pp. 563-566 ◽  
Author(s):  
P Hellstern ◽  
K Schilz ◽  
G von Blohn ◽  
E Wenzel

SummaryAn assay for rapid factor XIII activity measurement has been developed based on the determination of the ammonium released during fibrin stabilization. Factor XIII was activated by thrombin and calcium. Ammonium was measured by an ammonium-sensitive electrode. It was demonstrated that the assay procedure yields accurate and precise results and that factor XIII-catalyzed fibrin stabilization can be measured kinetically. The amount of ammonium released during the first 90 min of fibrin stabilization was found to be 7.8 ± 0.5 moles per mole fibrinogen, which is in agreement with the findings of other authors. In 15 normal subjects and in 15 patients suffering from diseases with suspected factor XIII deficiency there was a satisfactory correlation between the results obtained by the “ammonium-release-method”, Bohn’s method, and the immunological assay (r1 = 0.65; r2= 0.70; p<0.01). In 3 of 5 patients with paraproteinemias the values of factor XIII activity determined by the ammonium-release method were markedly lower than those estimated by the other methods. It could be shown that inhibitor mechanisms were responsible for these discrepancies.


Trials ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Mingcai Zhang ◽  
Guoqing Du ◽  
Congying Liu ◽  
Wei Li ◽  
Jiayu Yang ◽  
...  

Abstract Background Neck pain is a common clinical disease, which seriously affects people’s mental health and quality of life and results in loss of social productivity. Improving neck pain’s curative effect and reducing its recurrence rate are major medical problems. Shi’s manipulation therapy has unique advantages and technical features that aid in the diagnosis and treatment of neck pain. Compared with first-line non-steroidal anti-inflammatory drug (NSAID) treatment of neck pain, Shi’s cervical manipulation lacks the relevant research basis of therapeutic advantage, safety, and satisfaction for treating acute and subacute neck pain. Herein, we aim to confirm our hypothesis in a clinical trial that the safety and efficacy of Shi’s cervical manipulation will be more effective, safer, and more satisfactory than NSAIDs to treat acute and subacute neck pain. Methods In this multicenter, positive-controlled, randomized clinical trial, traditional analgesic drug (NSAID) is used to evaluate and show that Shi’s manipulation is more effective, safe, and satisfactory for treating acute and subacute neck pain. Overall, 240 subjects are randomly divided into the trial and control groups, with both groups treated by the corresponding main intervention method for up to 12 weeks. Clinical data will be collected before the intervention and immediately after the first treatment; at 3 days and 1, 2, 4, 8, and 12 weeks after the intervention; and at 26 and 52 weeks after treatment follow-up of clinical observation index data collection. The clinical observation indices are as follows: (1) cervical pain is the primary observation index, measured by Numerical Rating Scale. The secondary indices include the following: (2) cervical dysfunction index, measured by patient self-evaluation using cervical Neck Disability Index; (3) cervical activity measurement, measured by the cervical vertebra mobility measurement program of Android mobile phone system; (4) overall improvement, measured by patient self-evaluation with SF-36; and (5) satisfactory treatment, determined by patient self-evaluation. Discussion We will discuss whether Shi’s cervical manipulation has greater advantages in efficacy, safety, and satisfaction of acute and subacute neck pain than traditional NSAIDs, to provide a scientific basis for the dissemination and application of Shi’s cervical manipulation. Trial registration China Registered Clinical Trial Registration Center ChiCTR1900021371. Registered on 17 February 2019


2021 ◽  
Author(s):  
Hideto Hiraide ◽  
Yuki Tobimatsu ◽  
Arata Yoshinaga ◽  
Pui Ying Lam ◽  
Masaru Kobayashi ◽  
...  

Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 468
Author(s):  
Anna Pawlik ◽  
Beata Ciołek ◽  
Justyna Sulej ◽  
Andrzej Mazur ◽  
Przemysław Grela ◽  
...  

A white rot fungus Cerrena unicolor has been identified as an important source of laccase, unfortunately regulation of this enzyme genes expression is poorly understood. Using 1D and 2D PAGE and LC-MS/MS, laccase isoenzymes were investigated in the liquid filtrate of C. unicolor culture. The level of expression of laccase genes was measured using qPCR. The elevated concentrations of copper and manganese in the medium caused greatest change in genes expression and three laccase transcripts were significantly affected after culture temperature was decreased from 28 to 4 °C or increased to 40 °C. The small differences in the PAGE band intensities of individual laccase proteins were also observed, indicating that given compound affect particular laccase’s transcript. Analyses of laccase-specific activity, at all tested conditions, showed the increased activities as compared to the control, suggesting that enzyme is regulated at the post-translational stage. We observed that the aspartic protease purified from C. unicolor, significantly stimulate laccase activity. Moreover, electrochemical analysis of protease-treated laccase sample had 5 times higher redox peaks. The obtained results indicate that laccases released by C. unicolor are regulated at transcriptional, translational, and at the post-translational steps of gene expression helping fungus adapt to the environmental changes.


2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Mariko Takano ◽  
Masaya Nakamura ◽  
Masanobu Tabata

AbstractWe performed an analysis using isoelectric focusing to comprehensively clarify the isozyme composition of laccase derived from Japanese lacquer tree, Toxicodendron vernicifluum. When water extracts of acetone powder obtained from lacquer were subjected to isoelectric focusing, five bands within pI 7.35–9.30 and nine bands within pI 3.50–5.25 were detected using Coomassie staining. Similarly, laccase activity staining using guaiacol showed five bands within pI 7.35–9.30 and three bands within pI 3.50–4.25. However, laccase activity staining using gallic acid showed remarkable staining within pI 3.50–5.85, whereas staining was very weak within pI 7.35–9.30. When the water extracts of acetone powder were fractionated into the fractions containing bands within pI 7.35–9.30 and pI 3.50–5.85 by SP-Sepharose column chromatography, the former had a blue color and the latter a yellow color. The laccase activity was measured for each of the fractions in buffer solution in the pH range of 2.5–8.0. When syringaldazine, guaiacol, and 2,6-dimethoxyphenol were used as substrates, the yellow fraction showed considerably higher activity than the blue fraction for pH 5.5–7.5. When 3-methylcatechol and 4-methylcatechol were used as substrates, the yellow fraction showed higher activity for pH 4.5–6.5, and the blue fraction showed higher activity for pH 7.0–8.0. When 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) was used as the substrate, both fractions showed maximum activity at optimum pH of 3.0–4.0. Conventionally, in research on blue laccase derived from lacquer, the non-blue fraction corresponding to the yellow fraction lower than pI 6 has been removed during the purification process and thus has not been analyzed. Our results indicated that yellow laccase was present in the non-blue components of lacquer and that it may play a role in urushiol polymerization with previously reported blue laccase.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1566
Author(s):  
Elena Fabris ◽  
Michela Bulfoni ◽  
Alessandro Nencioni ◽  
Emanuele Nencioni

Introduction: Alpha-galactosidase (α-Gal) is an enzyme responsible for the hydrolyzation of glycolipids and glycoprotein commonly found in dietary sources. More than 20% of the general population suffers from abdominal pain or discomfort caused by intestinal gas and by indigested or partially digested food residuals. Therefore, α-Gal is used in dietary supplements to reduce intestinal gases and help complex food digestion. Marketed enzyme-containing dietary supplements must be produced in accordance with the Food and Drug Administration (FDA) regulations for Current Good Manufacturing Practice (cGMPs). Aim: in this work we illustrated the process used to develop and validate a spectrophotometric enzymatic assay for α-Gal activity quantification in dietary supplements. Methods: The validation workflow included an initial statistical-phase optimization of materials, reagents, and conditions, and subsequently a comparative study with another fluorimetric assay. A final validation of method performance in terms of specificity, linearity, accuracy, intermediate-precision repeatability, and system precision was then executed. Results and conclusions: The proven method achieved good performance in the quantitative determination of α-Gal activity in commercial food supplements in accordance with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals (ICH) guidelines and is suitable as a rapid in-house quality control test.


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