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1.
Mycotoxin Res ; 40(2): 269-277, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38421516

RESUMEN

This experiment was conducted to determine the effect of an adsorbent material based on powdered alfalfa leaves added in the aflatoxin B1 (AFB1)-contaminated diet of turkey poults on production parameters, blood cell count, serum biochemistry, liver enzymes, and liver histology. For this purpose, three hundred and fifty female Nicholas-700 poults were randomly assigned into five treatments: (1) Control, AFB1-free diet; (2) AF, diet contaminated with 250 ng AFB1/g; (3) Alfalfa, AFB1-free diet + 0.5% (w/w) adsorbent; (4) AF+alfalfa, diet contaminated with 250 ng AFB1/g + 0.5% (w/w) adsorbent, and (5) AF+ yeast cell wall (YCW), diet contaminated with 250 ng AFB1/g + 0.5% (w/w) of yeast cell wall (a commercial mycotoxin binder used as reference material). The in vivo efficacy of powdered alfalfa leaves was assessed during a 28-day period. In general, the addition of powdered alfalfa leaves in the AFB1-free diet gave the best performance results (body weight, body weight gain, and feed intake) and improved the values of total protein, glucose, calcium, creatinine, and blood urea nitrogen. Moreover, the addition of powdered alfalfa leaves in the AFB1-contaminated diet enhanced body weight and body weight gain and significantly reduced the feed intake, compared to the AF and AF+YCW groups. Additionally, significant alterations in serum parameters were observed in poults intoxicated with the AFB1, compared to the Control group. Furthermore, typical histopathological lesions were observed in the liver of the AF group, which were significantly ameliorated with the addition of powdered alfalfa leaves. Conclusively, these results pointed out that low inclusion of powdered alfalfa leaves in the contaminated feed counteracted the adverse effects of AFB1 in turkey poults.


Asunto(s)
Aflatoxina B1 , Alimentación Animal , Medicago sativa , Hojas de la Planta , Pavos , Animales , Aflatoxina B1/toxicidad , Medicago sativa/química , Hojas de la Planta/química , Alimentación Animal/análisis , Femenino , Hígado/efectos de los fármacos , Hígado/patología , Dieta/veterinaria , Polvos , Peso Corporal/efectos de los fármacos
3.
Front Vet Sci ; 10: 1276754, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37881447

RESUMEN

This study aims to evaluate the efficacy of humic acid (HA) from worm compost as an adsorbent for aflatoxin B1 (AFB1) in turkey poults. The experiment involved the inclusion of 0.25% (w/w) HA in the diet of turkey poults consuming aflatoxin-contaminated feed (250 ng AFB1/g). A total of 350 1-day-old female Nicholas-700 turkey poults were randomly allocated to five equal groups: negative control (basal diet); positive control (basal diet + 250 ng AFB1/g; HA (basal diet + 0.25% HA); HA + AFB1 (basal diet + HA + 250 ng AFB1/g); and zeolite + AFB1 (basal diet + 0.25% zeolite + 250 ng AFB1/g). Each group had seven replicates of 10 poults (n = 70). The impact of HA addition was evaluated in terms of performance parameters, relative organ weights, liver histological lesions, and serum biochemical and hematological constituents. In general, the addition of HA improved body weight (BW), body weight gain (BWG), and feed conversion rate (FCR). Furthermore, HA effectively mitigated the toxic effects caused by AFB1 in the majority of the analyzed variables. The results indicated that HA effectively counteracted the AFB1-induced toxic effects in turkey poults. Based on these findings, it can be concluded that HA is capable of removing AFB1 from the contaminated diet.

4.
Toxins (Basel) ; 15(7)2023 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-37505702

RESUMEN

This study aimed to investigate the efficacy of a feed additive containing bentonite and enzymatically hydrolyzed yeast on the intestinal health and growth of newly weaned pigs under chronic dietary exposure to fumonisin and aflatoxin. Newly weaned pigs were randomly allotted to one of four possible treatments: a control diet of conventional corn; a diet of corn contaminated with fumonisin and aflatoxin; a diet of mycotoxin-contaminated corn with 0.2% of feed additive; and a diet of mycotoxin contaminated corn with 0.4% of feed additive. We observed lower average weight gain and average daily feed intake in pigs that were fed only mycotoxin-contaminated corn compared to the control group. Feed additive supplementation linearly increased both average weight gain and feed intake, as well as tumor necrosis factor-alpha. In the jejunum, there was an observed decrease in immunoglobulin A and an increase in claudin-1. Additionally, feed additive supplementation increased the villus height to crypt depth ratio compared to the control. In conclusion, feed additives containing bentonite and enzymatically hydrolyzed yeast could mitigate the detrimental effects of mycotoxins on the growth performance of newly weaned pigs by improving intestinal integrity and positively modulating immune response.


Asunto(s)
Aflatoxinas , Fumonisinas , Micotoxinas , Porcinos , Animales , Fumonisinas/toxicidad , Saccharomyces cerevisiae , Bentonita , Aflatoxinas/toxicidad , Suplementos Dietéticos/análisis , Dieta/veterinaria , Micotoxinas/toxicidad , Aumento de Peso , Alimentación Animal/análisis
5.
J AOAC Int ; 106(3): 645-651, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-36912688

RESUMEN

BACKGROUND: Aflatoxins (AFs) are common feed contaminants and are one of the common causes of toxin-related pet food poisoning and recalls. OBJECTIVE: Currently, there are no validated methods for the detection and quantitation of AFs in biological matrices to diagnose AF exposure in live animals. Following a successful intra-laboratory method development to quantify AFB1 and AFM1 in animal urine by HPLC with fluorescence detection (HPLC-FLD), the present study was conducted to extensively evaluate the method performance in an unbiased manner using blinded samples. METHODS: The evaluation included two stages. First, the performance was verified in the method-originating laboratory in a single-laboratory blinded method test (BMT-S) trial followed by a multi-laboratory blinded method test (BMT-M) trial. RESULTS: In both trials, accuracy, repeatability, and reproducibility were satisfactory confirming the relatively good ruggedness and robustness of the method and ensuring that it will perform as expected if used by other laboratories in the future. CONCLUSIONS: We extensively evaluated the performance of a quantitative method to detect AFB1 and AFM1 in animal urine by HPLC-FLD by two different laboratories in two separate BMT-S and BMT-M trials. Both BMT results demonstrated the satisfactory accuracy and precision of the method. It is now available to be adopted by other diagnostic laboratories for purposes of diagnosing AF intoxication in animals. HIGHLIGHTS: A simple urine-based diagnostic test method using HPLC-FLD that originated in a single laboratory now has passed a multi-laboratory evaluation and is now available to be shared with other diagnostic laboratories for purposes of diagnosing AF intoxication in animals so better treatment can be rendered.


Asunto(s)
Aflatoxina B1 , Aflatoxinas , Animales , Aflatoxina B1/análisis , Aflatoxinas/análisis , Cromatografía Líquida de Alta Presión/métodos , Contaminación de Alimentos/análisis , Reproducibilidad de los Resultados
6.
ACS Omega ; 7(45): 41548-41558, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36406527

RESUMEN

Lignin-containing nanocelluloses (LNCs) have the properties of both lignin and nanocellulose and could overcome the limits of both individual components in metallic nanoparticle synthesis. However, studies on LNCs are still limited, and the potential of such nanomaterials for metallic nanoparticle synthesis has not been fully unraveled. In this study, monometallic silver, gold nanoparticles, and Ag-Au-AgCl nanohybrids were synthesized in situ utilizing LNCs in a chemical-free approach. The parameters, including Ag+ and Au3+ concentrations as well as [Au3+]/[Ag+] ratios, were investigated for their effects on the nanoparticle synthesis. The characterizations, including UV-vis spectrophotometry, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), confirmed the coexistence of Ag, Au, and AgCl while indicating the key role of lignin and oxygen-containing functional groups in the nanoparticle synthesis. The as-synthesized AgNPs-, AuNPs-, and nanohybrids-LNC samples were tested for their antibacterial activities. In comparison to the monometallic AgNPs-LNC sample, nanohybrids-LNC synthesized with 0.063 mM Au3+ loading showed superior antibacterial activities with minimum inhibitory concentrations (MICs) at 5 µg/mL against Gram-positive Staphylococcus aureus and 10 µg/mL against Gram-negative Salmonella typhimurium with controlled Ag+ release. The results indicated that LNCs can be used to synthesize metallic nanoparticles, and the resultant Ag-Au-AgCl nanohybrids were a potent antibacterial agent with reduced environmental impacts.

7.
BMC Res Notes ; 12(1): 492, 2019 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-31391088

RESUMEN

OBJECTIVE: Comparison was done between high-performance liquid chromatography (HPLC) and a competitive enzyme-linked immunosorbent assay (ELISA) for detection and quantification of aflatoxin B1 (AFB1) in feed samples. The two procedures were standardized and validated before the actual experiment. Five concentrations (0, 5, 10, 20 and 30 ppb) of feed samples were used for both methods. For the HPLC technique, the samples were extracted in acetonitrile/water (90/10) solution, cleaned-up using solid phase extraction (SPE) column, and derivatized by water/trifluoroacetic acid/glacial acetic acid (35/10/5) solution before instrument analysis. The samples were extracted in 70% methanol for the ELISA technique. RESULTS: The two tests showed very strong linearity with correlation coefficient value of > 0.99 using standard solutions. The mean recovery rate was 92.42% (with relative standard deviation (RSD) of 5.97) and 75.64% (RSD = 34.88) for HPLC and ELISA, respectively. There was no statistically significant difference in recovery rate between the two methods. There was a positive correlation (r = 0.84) between them which indicated that the two techniques can be used to detect and quantify aflatoxin B1 in feed samples. However, there were variations among replicates for the ELISA method, which shows that this method is more applicable for screening purposes.


Asunto(s)
Aflatoxina B1/aislamiento & purificación , Cromatografía Líquida de Alta Presión/normas , Ensayo de Inmunoadsorción Enzimática/normas , Contaminación de Alimentos/análisis , Zea mays/química , Acetonitrilos/química , Alimentación Animal/análisis , Animales , Cromatografía Líquida de Alta Presión/métodos , Ensayo de Inmunoadsorción Enzimática/métodos , Etanol/química , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Extracción en Fase Sólida/métodos , Solventes/química , Agua/química
8.
J AOAC Int ; 102(5): 1530-1534, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30736868

RESUMEN

Background: Aflatoxins (AFs) are secondary metabolites of fungi and are one of the causes of toxin-related pet food recalls. An intralaboratory method was previously developed to quantify aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1) in animal liver by HPLC with fluorescence detection. Objective: The aim of this study was to extensively evaluate the method performance with a single-laboratory blinded method test (BMT-S) and a multilaboratory blinded method test (BMT-M). Methods: Blinded tissue samples were prepared by a third-party laboratory and sent out to participating laboratories for both BMT-S and BMT-M. Results: In both tests, participants analyzed blinded samples prepared by an independent laboratory. In the BMT-S, accuracy ranged between 111 and 154% for AFB1 and 113 and 159% for AFM1 within the quantitation range of 0.1-0.5 ng/g. The HorRat values for repeatability ranged between 0.1 and 0.3 for AFB1 and 0.3 and 0.6 for AFM1. In the BMT-M, the interlaboratory accuracy ranged between 77 and 81% for AFB1 and 83 and 85% for AFM1 within the quantitation range of 0.2-10 ng/g. The HorRat values for reproducibility ranged between 0.4 and 0.7 for AFB1 and 0.4 and 0.9 for AFM1. Both recovery and reproducibility were acceptable. Conclusions: BMT-M evaluation demonstrated that the method was suitable for quantitation of aflatoxins B1 and M1 in animal liver between laboratories. Highlights: The BMT-S and BMT-M results demonstrated that the method is rugged and reproducible among the participating laboratories.


Asunto(s)
Aflatoxina B1/análisis , Aflatoxina M1/análisis , Cromatografía Líquida de Alta Presión/métodos , Hígado/química , Animales , Fluorescencia , Reproducibilidad de los Resultados
9.
J Anal Toxicol ; 41(8): 698-707, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28985321

RESUMEN

Mycotoxins negatively impact animal health. Aflatoxins (AFs) are the most common mycotoxins affecting both large and small animals and are a common cause of toxin-related pet food recalls. Definitive diagnosis of aflatoxicosis is constrained by a lack of validated ante-mortem analytical methods for detection and quantitation of AFs and their metabolites in biological specimens. Herein, we developed and evaluated a urine-based quantitative method for measurement of aflatoxin B1 (AFB1) and its metabolites aflatoxin M1 (AFM1) and aflatoxin Q1 (AFQ1) in animal urine. (Some of the results have been presented at 59th AAVLD conference, Greensboro, North Carolina, October 13-19th, 2016.) This method uses an immuno-affinity column for clean-up and pre-column derivatization followed by high performance liquid chromatography analysis with fluorescence detection. The method has high selectivity, recovery (>81%) and sensitivity with an instrument limit of detection of 0.20-1.02 pg; instrument limit of quantitation of 0.77-4.46 pg; and a method lower limit of quantitation of 0.30-2.5 ng/mL. The method has high accuracy, repeatability, and is rugged against minor changes. However, because of poor sensitivity of AFQ1 at low concentrations we recommend this method for quantitative determination of AFB1 and AFM1, and for qualitative measurement of AFQ1 in animal urine for diagnosis of aflatoxicosis.


Asunto(s)
Aflatoxinas/orina , Aflatoxina B1/orina , Aflatoxina M1/orina , Animales , Cromatografía Líquida de Alta Presión , Fluorescencia , Urinálisis
10.
Int J Parasitol Drugs Drug Resist ; 7(1): 12-22, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28033523

RESUMEN

Nematode parasites infect ∼2 billion people world-wide. Infections are treated and prevented by anthelmintic drugs, some of which act on nicotinic acetylcholine receptors (nAChRs). There is an unmet need for novel therapeutic agents because of concerns about the development of resistance. We have selected Asu-ACR-16 from a significant nematode parasite genus, Ascaris suum, as a pharmaceutical target and nicotine as our basic moiety (EC50 6.21 ± 0.56 µM, Imax 82.39 ± 2.52%) to facilitate the development of more effective anthelmintics. We expressed Asu-ACR-16 in Xenopus oocytes and used two-electrode voltage clamp electrophysiology to determine agonist concentration-current-response relationships and determine the potencies (EC50s) of the agonists. Here, we describe the synthesis of a novel agonist, (S)-5-ethynyl-anabasine, and show that it is more potent (EC50 0.14 ± 0.01 µM) than other nicotine alkaloids on Asu-ACR-16. Agonists acting on ACR-16 receptors have the potential to circumvent drug resistance to anthelmintics, like levamisole, that do not act on the ACR-16 receptors.


Asunto(s)
Anabasina/análogos & derivados , Ascaris suum/metabolismo , Agonistas Nicotínicos/farmacología , Receptores Nicotínicos/metabolismo , Anabasina/síntesis química , Anabasina/metabolismo , Anabasina/farmacología , Animales , Ascaris suum/genética , Descubrimiento de Drogas , Levamisol/farmacología , Agonistas Nicotínicos/síntesis química , Agonistas Nicotínicos/química , Agonistas Nicotínicos/aislamiento & purificación , Oocitos , Xenopus/genética
11.
Org Lett ; 17(13): 3276-9, 2015 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-26098453

RESUMEN

Tandem reactions involving Rh-catalyzed intermolecular hydroacylations of alkynes with salicylaldehydes followed by intramolecular oxo-Michael additions are described for the diastereoselective synthesis of 2,3-disubstituted chroman-4-ones. The tandem hydroacylation/oxo-Michael additions occur to form 2,3-disubstituted chroman-4-ones in high yields from a range of 1,2-disubstituted acetylenes and substituted salicylaldehyes. The resulting 2,3-disubstituted chroman-4-ones are readily fluorinated to form trans-3-fluoro-2,3-disubstituted chroman-4-ones in high yields with excellent diastereoselectivity.


Asunto(s)
Alquinos/química , Cromonas/síntesis química , Hidrocarburos Fluorados/síntesis química , Rodio/química , Aldehídos/química , Catálisis , Cromonas/química , Halogenación , Hidrocarburos Fluorados/química , Estructura Molecular , Estereoisomerismo
12.
Org Lett ; 16(15): 4036-9, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25020184

RESUMEN

Catalytic, enantioselective hydroacylations of N-allylindole-2-carboxaldehydes and N-allylpyrrole-2-carboxaldehydes are reported. In contrast to many alkene hydroacylations that form six-membered rings, these annulative processes occur in the absence of ancillary functionality to stabilize the acylrhodium(III) hydride intermediate. The intramolecular hydroacylation reactions generate 7,8-dihydropyrido[1,2-a]indol-9(6H)ones and 6,7-dihydroindolizin-8(5H)-ones in moderate to high yields with excellent enantioselectivities.


Asunto(s)
Aldehídos/química , Alquenos/química , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/síntesis química , Cetonas/síntesis química , Nitrógeno/química , Rodio/química , Catálisis , Quelantes/química , Cetonas/química , Estructura Molecular , Estereoisomerismo
13.
Org Lett ; 14(20): 5326-9, 2012 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-23035967

RESUMEN

A simple and straightforward method for the preparation of indole-3-carboxylic acids was discovered through the direct carboxylation of indoles with atmospheric pressure of carbon dioxide (CO(2)) under basic conditions. The key for the reaction was found to be the use of a large excess of LiO(t)Bu as a base to suppress the undesired decarboxylation side reaction.

14.
J Org Chem ; 76(21): 9175-81, 2011 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-21939236

RESUMEN

The gold-catalyzed tandem cyclization of 1,2-bis(alkynyl)-2-en-1-ones with indoles offers an efficient and straightforward route to indole-fused polycyclic systems. The process is realized through a cascade carbonyl-yne cyclization/Friedel-Crafts/indole-yne cyclization sequence catalyzed by a single-pot catalyst of gold.


Asunto(s)
Alquinos/química , Oro/química , Indoles/síntesis química , Catálisis , Ciclización , Indoles/química , Estructura Molecular
16.
J Org Chem ; 75(2): 510-3, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20000736

RESUMEN

An efficient access to N-phth pyrrroles via gold-catalyzed cycloisomerization of N-phth alkynylaziridines has been described. Functionalized pyrroles including pyrrole-2-carboxylates or 2-pyrrolyl ketone are easily constructed in generally good yields by this method. The resulting pyrroles can be further converted to N-amino pyrrole or 2-acyl pyrrole, which are important synthetic intermediates for amplification of molecular complexity.


Asunto(s)
Alquinos/química , Aziridinas/química , Oro/química , Ácidos Ftálicos/química , Pirroles/química , Catálisis , Ciclización , Estructura Molecular , Estereoisomerismo
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