scholarly journals Efficient Degradation of Aflatoxin B1 and Zearalenone by Laccase-like Multicopper Oxidase from Streptomyces thermocarboxydus in the Presence of Mediators

Toxins ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 754
Author(s):  
Xing Qin ◽  
Yanzhe Xin ◽  
Jiahuan Zou ◽  
Xiaoyun Su ◽  
Xiaolu Wang ◽  
...  
Keyword(s):  
Aflatoxin B1 ◽  
Degradation Products ◽  
Copper Ion ◽  
Blue Color ◽  
Multicopper Oxidases ◽  
Simultaneous Reduction ◽  
Mycotoxin Degradation ◽  
Bivalent Copper ◽  
Encoding Gene ◽  
Degradation Ability

Multicopper oxidases (MCOs) are a diverse group of enzymes that could catalyze the oxidation of different xenobiotic compounds, with simultaneous reduction in oxygen to water. Aside from laccase, one member of the MCO superfamily has shown great potential in the biodegradation of mycotoxins; however, the mycotoxin degradation ability of other MCOs is uncertain. In this study, a novel MCO-encoding gene, StMCO, from Streptomyces thermocarboxydus, was identified, cloned, and heterologously expressed in Escherichia coli. The purified recombinant StMCO exhibited the characteristic blue color and bivalent copper ion-dependent enzyme activity. It was capable of oxidizing the model substrate ABTS, phenolic compound DMP, and azo dye RB5. Notably, StMCO could directly degrade aflatoxin B1 (AFB1) and zearalenone (ZEN) in the absence of mediators. Meanwhile, the presence of various lignin unit-derived natural mediators or ABTS could significantly accelerate the degradation of AFB1 and ZEN by StMCO. Furthermore, the biological toxicities of their corresponding degradation products, AFQ1 and 13-OH-ZEN-quinone, were remarkably decreased. Our findings suggested that efficient degradation of mycotoxins with mediators might be a common feature of the MCOs superfamily. In summary, the unique properties of MCOs make them good candidates for degrading multiple major mycotoxins in contaminated feed and food.

Structure elucidation and toxicity analyses of the degradation products of aflatoxin B1 by aqueous ozone

Food Control ◽  
2013 ◽  
Vol 31 (2) ◽  
pp. 331-336 ◽  
Author(s):  
Xiaohu Luo ◽  
Ren Wang ◽  
Li Wang ◽  
Yong Wang ◽  
Zhengxing Chen
Keyword(s):  
Aflatoxin B1 ◽  
Structure Elucidation ◽  
Degradation Products

Identification of degradation products of d(C-G) by a 1,10-phenanthroline-copper ion complex

1982 ◽  
Vol 104 (20) ◽  
pp. 5494-5495 ◽  
Author(s):  
Seiichi Uesugi ◽  
Toshio Shida ◽  
Morio Ikehara ◽  
Yuji Kobayashi ◽  
Yoshimasa Kyogoku
Keyword(s):  
Degradation Products ◽  
Copper Ion

Interaction of Mycotoxins with Copper-Folin Reagent

1978 ◽  
Vol 41 (5) ◽  
pp. 370-372
Author(s):  
MOHAMED Y. SIRAJ ◽  
TIMOTHY D. PHILLIPS ◽  
A. WALLACE HAYES
Keyword(s):  
Linear Relationship ◽  
Aflatoxin B1 ◽  
Analytical Method ◽  
Cytochalasin B ◽  
High Sensitivity ◽  
Blue Color ◽  
Penicillic Acid ◽  
Toxin Concentration ◽  
Color Development ◽  
Positive Materials

To study the interference by mycotoxins in protein measurements, solutions of various concentrations of aflatoxin B1, citrinin, cytochalasin B, ochratoxin A, patulin, penicillic acid, rubratoxins A and B, T-2 toxin and zearalenone were tested for a positive copper-Folin reaction. Except for T-2 toxin, all mycotoxins tested developed a blue color, characteristic of proteins, in the copper-Folin solution. The Lowry reaction for the mycotoxins was linear over the concentration range of 20–100 μg/ml for most of these toxins. Aflatoxin B1 and citrinin at 2 μg/ml and zearalenone at 0.5 mg/ml developed a blue color in the copper-Folin solution. The linear relationship between color development and toxin concentration plus high sensitivity makes the copper-Folin reaction a potential analytical method for these toxins but only in the absence of protein or other copper-Folin positive materials.

scholarly journals Qualifying the T-2 Toxin-Degrading Properties of Seven Microbes with Zebrafish Embryo Microinjection Method

Toxins ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 460
Author(s):  
Edina Garai ◽  
Anita Risa ◽  
Emese Varga ◽  
Mátyás Cserháti ◽  
Balázs Kriszt ◽  
...  
Keyword(s):  
Sublethal Effects ◽  
Degradation Products ◽  
Rhodococcus Erythropolis ◽  
Bacterial Strains ◽  
Cell Stage ◽  
Bacterial Metabolites ◽  
Mycotoxin Degradation

T-2 mycotoxin degradation and detoxification efficiency of seven bacterial strains were investigated with zebrafish microinjection method in three steps ((1) determination of mycotoxin toxicity baseline, (2) examination of bacterial metabolites toxicity, (3) identification of degradation products toxicity). Toxicity of T-2 was used as a baseline of toxic effects, bacterial metabolites of strains as control of bacterial toxicity and degradation products of toxin as control of biodegradation were injected into one-cell stage embryos in the same experiment. The results of in vivo tests were checked and supplemented with UHPLC-MS/MS measurement of T-2 concentration of samples. Results showed that the Rhodococcus erythropolis NI1 strain was the only one of the seven tested (R. gordoniae AK38, R. ruber N361, R. coprophilus N774, R. rhodochrous NI2, R. globerulus N58, Gordonia paraffinivorans NZS14), which was appropriated to criteria all aspects (bacterial and degradation metabolites of strains caused lower toxicity effects than T-2, and strains were able to degrade T-2 mycotoxin). Bacterial and degradation metabolites of the NI1 strain caused slight lethal and sublethal effects on zebrafish embryos at 72- and 120-h postinjection. Results demonstrated that the three-step zebrafish microinjection method is well-suited to the determination and classification of different bacterial strains by their mycotoxin degradation and detoxification efficiency.

Size and shape regulated synthesis of silver nanocapsules for highly selective and sensitive ultralow bivalent copper ion sensor application

2017 ◽  
Vol 41 (10) ◽  
pp. 4006-4013 ◽  
Author(s):  
Balakumar Vellaichamy ◽  
Prakash Periakaruppan
Keyword(s):  
Copper Ions ◽  
Copper Ion ◽  
Colorimetric Sensing ◽  
Ion Sensor ◽  
Sensor Application ◽  
Size And Shape ◽  
Naked Eye ◽  
Bivalent Copper ◽  
Shape Controlled

The development of highly robust, quantitative, sensitive and naked eye colorimetric sensing of bivalent copper ions using bio-inspired synthesis of size and shape controlled silver nanocapsules (AgNCs) is reported herein.

Studies of bivalent copper ion binding to poly C

1985 ◽  
Vol 24 (2) ◽  
pp. 97-111 ◽  
Author(s):  
Victor A. Sorokin ◽  
Yuri P. Blagoi ◽  
Vladimir A. Valeev ◽  
Olga A. Antonova
Keyword(s):  
Copper Ion ◽  
Ion Binding ◽  
Bivalent Copper

scholarly journals Mycotoxin degradation by microbial metabolites

2020 ◽  
Author(s):  
N. V. Statsyuk ◽  
L. A. Shcherbakova ◽  
O. D. Mikityuk ◽  
T. A. Nazarova ◽  
V. G. Dzhavakhiya
Keyword(s):  
Aflatoxin B1 ◽  
Gliocladium Roseum ◽  
Microbial Metabolites ◽  
Mycotoxin Degradation ◽  
Extracellular Metabolites ◽  
Optimum Ph ◽  
Enzymatic Nature ◽  
Optimum Ph And Temperature

Extracellular metabolites of Gliocladium roseum GRZ7 are able to destroy aflatoxin B1 and zearalenone (by 61.9 and 68%, respectively). The determined optimum pH and temperature confirm the enzymatic nature of these metabolites.

scholarly journals A New Laccase of Lac 2 from the White Rot Fungus Cerrena unicolor 6884 and Lac 2-Mediated Degradation of Aflatoxin B1

Toxins ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 476 ◽  
Author(s):  
Zhimin Zhou ◽  
Renkuan Li ◽  
Tzi Bun Ng ◽  
Yunyun Lai ◽  
Jie Yang ◽  
...  
Keyword(s):  
Aflatoxin B1 ◽  
Environmental Pollutants ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Mass Spectrometry Data ◽  
White Rot ◽  
White Rot Fungus ◽  
Multicopper Oxidases ◽  
Cerrena Unicolor

Aflatoxin B1 (AFB1) is a known toxic human carcinogen and can be detoxified by laccases, which are multicopper oxidases that convert several environmental pollutants and toxins. In this study, a new laccase that could catalyze AFB1 degradation was purified and identified from the white-rot fungus Cerrena unicolor 6884. The laccase was purified using (NH4)2SO4 precipitation and anion exchange chromatography, and then identified as Lac 2 through zymogram and UHPLC-MS/MS based on the Illumina transcriptome analysis of C. unicolor 6884. Six putative laccase protein sequences were obtained via functional annotation. The lac 2 cDNA encoding a full-length protein of 512 amino acids was cloned and sequenced to expand the fungus laccase gene library for AFB1 detoxification. AFB1 degradation by Lac 2 was conducted in vitro at pH 7.0 and 45 °C for 24 h. The half-life of AFB1 degradation catalyzed by Lac 2 was 5.16 h. Acetosyringone (AS), Syrinagaldehyde (SA) and [2,2′ -azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS) at 1 mM concentration seemed to be similar mediators for strongly enhancing AFB1 degradation by Lac 2. The product of AFB1 degradation catalyzed by Lac 2 was traced and identified to be Aflatoxin Q1 (AFQ1) based on mass spectrometry data. These findings are promising for a possible application of Lac 2 as a new aflatoxin oxidase in degrading AFB1 present in food and feeds.

scholarly journals Biological Degradation of Aflatoxin B1 by Cell-Free Extracts of Bacillus velezensis DY3108 with Broad PH Stability and Excellent Thermostability

Toxins ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 330 ◽  
Author(s):  
Xian Shu ◽  
Yuting Wang ◽  
Qing Zhou ◽  
Minghao Li ◽  
Hao Hu ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Aflatoxin B1 ◽  
High Performance ◽  
Degradation Products ◽  
Sodium Dodecyl ◽  
Aflatoxin Contamination ◽  
Proteinase K ◽  
Biological Degradation ◽  
Bacillus Velezensis ◽  
Degrading Bacteria

(1) Background: Aflatoxin contamination in food and grain poses serious problems both for economic development and public health protection, thus leading to a focus on an effective approach to control it; (2) Methods: Aflatoxin B1 (AFB1) degrading bacteria were isolated using a medium containing coumarin as the sole carbon source, and the biodegradation of AFB1 by the isolate was examined by high performance liquid chromatography, and liquid chromatography mass spectrometry; (3) Results: a bacterial strain exhibiting strong AFB1 degradation activity (91.5%) was isolated and identified as Bacillus velezensis DY3108. The AFB1 degrading activity was predominantly attributed to the cell-free supernatant of strain DY3108. Besides, it was heat-stable and resistant to proteinase K treatment but sensitive to sodium dodecyl sulfate treatment. The optimal temperature for the maximal degradation of AFB1 was 80 °C. Even more notable, the supernatant showed a high level of activity over a broad pH (4.0 to 11.0) and exhibited the highest degradation (94.70%) at pH 8.0. Cytotoxicity assays indicated that the degradation products displayed significantly (p < 0.05) lower cytotoxic effects than the parent AFB1; (4) Conclusions: B. velezensis DY3108 might be a promising candidate for exploitation in AFB1 detoxification and bioremediation in food and feed matrices.

ChemInform Abstract: IDENTIFICATION OF DEGRADATION PRODUCTS OF D(C-G) BY A 1,10-PHENANTHROLINE-COPPER ION COMPLEX

1983 ◽  
Vol 14 (1) ◽  
Author(s):  
S. UESUGI ◽  
T. SHIDA ◽  
M. IKEHARA ◽  
Y. KOBAYASHI ◽  
Y. KYOGOKU
Keyword(s):  
Degradation Products ◽  
Copper Ion
Sign in / Sign up

Export Citation Format

Share Document