Additional Pressure to a Threatened Species: High Persistent Organic Pollutant Concentrations in the Tropical Estuarine Batoid Gymnura altavela.

Persistent organic pollutants (POPs) were determined in Gymnura altavela liver samples from one of the most impacted estuarine environments in the Atlantic Ocean (Guanabara Bay, Brazil). PCBs were the predominant compounds (91.2%) averaging 6773 ± 4659 ng.g-1 lipid weight (lw). DDT, Mirex, HCH and HCB concentrations were 633 ± 715, 6.2 ± 9.3, 3.4 ± 1.4 and 0.5 ± 0.5 ng.g-1 lw, respectively. Recent DDT input in the estuary was minimum, as verified by the p,p'-DDE/∑DDT ratio (0.67). The prevalence of industrial compounds was highlighted by the ΣDDT/ΣPCB ratio (0.08). A negative correlation detected between disc width and PCBs, Mirex and HCH concentrations may be a consequence of maternal offloading. High POP concentrations in G. altavela liver samples from Guanabara Bay suggests that PCBs, in particular, may pressure the conservation of this threatened with extinction tropical estuarine batoid species.

A Mouse Model of Targeted Musashi1 Expression in Whole Intestinal Epithelium Suggests Regulatory Roles in Cell Cycle and Stemness.

The intestinal epithelium is very peculiar for its continuous cell renewal, fuelled by multipotent stem cells localized within the crypts of Lieberkühn. Several lines of evidence have established the evolutionary conserved RNA-binding protein Musashi1 as a marker of adult stem cells, including those of the intestinal epithelium, and revealed its roles in stem cell self-renewal and cell fate determination. Previous studies from our laboratories have shown that Musashi1 controls stem cell-like features in medulloblastoma, glioblastoma, and breast cancer cells, and has pro-proliferative and pro-tumorigenic properties in intestinal epithelial progenitor cells in vitro. To undertake a detailed study of Musashi1's function in the intestinal epithelium in vivo, we have generated a mouse model, referred to as v-Msi, overexpressing Musashi1 specifically in the entire intestinal epithelium. Compared with wild type litters, v-Msi1 mice exhibited increased intestinal crypt size accompanied by enhanced proliferation. Comparative transcriptomics by RNA-seq revealed Musashi1's association with gut stem cell signature, cell cycle, DNA replication, and drug metabolism. Finally, we identified and validated three novel mRNA targets that are stabilized by Musashi1, Ccnd1 (Cyclin D1), Cdk6, and Sox4. In conclusion, the targeted expression of Musashi1 in the intestinal epithelium in vivo increases the cell proliferation rate and strongly suggests its action on stem cells activity. This is due to the modulation of a complex network of gene functions and pathways including drug metabolism, cell cycle, and DNA synthesis and repair.

Anti-inflammatory effect of dialysable leucocyte extract in a rat model of osteoarthritis: histopathological and molecular characterization.

OBJECTIVES: To evaluate the effect of dialysable leucocyte extract (DLE) on pro- and anti-inflammatory profiles in a rat model of osteoarthritis (OA). METHOD: Forty-eight male Wistar rats were divided into three groups: normal rats without treatment, OA rats treated with placebo, and OA rats treated with DLE. After treatment, the animals were killed to obtain cartilage for histological analysis and to determine the expression of pro- and anti-inflammatory cytokines by reverse transcription multiplex polymerase chain reaction (RT-MPCR) and immunohistofluorescence analyses. RESULTS: Histological analysis revealed that OA cartilage from rats treated with DLE displayed similar characteristics to non-OA cartilage from the control group. The OA cartilage treated with placebo showed alterations in the cellular architecture and in chondrocyte cluster formation. Analysis of cytokine expression by RT-MPCR showed that OA cartilage from DLE-treated rats expressed platelet-derived growth factor (PDGF), interferon (IFN)-γ, and fibroblast growth factor (FGF)-2, similar to non-OA cartilage from the control group. However, OA cartilage from rats treated with placebo expressed interleukin (IL)-1, PDGF, and I kappa B (IκB). Confocal immunodetection of FGF-2, PDGF, and non-phosphorylated IκB showed that they were distributed in the cytoplasm of most chondrocytes in OA cartilage from DLE-treated rats whereas no nuclear factor kappa B (NF-κB) expression was observed in the nuclei. Instead, in OA cartilage from the placebo group, only weak FGF-2 staining was observed, PDGF and IκB were not detected, and NF-κB was strongly observed in both cytoplasm and nuclei. CONCLUSIONS: Our findings suggest that DLE treatment modifies the OA process, promoting the expression of anti-inflammatory cytokines and diminishing the inflammatory effects, avoiding the nuclear translocation of NF-κB in chondrocytes.

Spatial and temporal distribution patterns of the silver mojarra Eucinostomus argenteus (Perciformes: Gerreidae) in a tropical semi-enclosed bay.

This study determined the spatial and temporal distributions of the silver mojarra Eucinostomus argenteus (Perciformes: Gerreidae), one of the most abundant teleost species in bays and estuaries. Sampling was conducted from July 2005 to June 2007. The species was captured on all sampling dates and at six of the seven sampling stations. Approximately 80% of the individuals were below the size of first sexual maturity (12·0 cm total length, LT ). Although the spatial distribution of juveniles and adults differed throughout the study period, the environmental variables measured explained only a small part of their distribution. The recruitment period occurred during the first part of each year. Despite the high pollution levels in Guanabara Bay, this coastal system plays an important role as a nursery ground and for the growth of E. argenteus.

Characterization of Aspergillus section Flavi isolated from organic Brazil nuts using a polyphasic approach.

Brazil nut (Bertholletia excelsa), an important non-timber forest product from Amazonia, is commercialized in worldwide markets. The main importers of this nut are North America and European countries, where the demand for organic products has grown to meet consumers concerned about food safety. Thus, the precise identification of toxigenic fungi is important because the Brazil nut is susceptible to colonization by these microorganisms. The present study aimed to characterize by polyphasic approach strains of Aspergillus section Flavi from organic Brazil nuts. The results showed Aspergillus flavus as the main species found (74.4%), followed by Aspergillus nomius (12.7%). The potential mycotoxigenic revealed that 80.0% of A. flavus were toxin producers, 14.3% of which produced only aflatoxin B (AFB), 22.85% of which produced only cyclopiazonic acid (CPA), and 42.85% produced both them. All strains of A. nomius were AFB and AFG producers and did not produce CPA. There is no consensus about what Aspergillus species predominates on Brazil nuts. Apparently, the origin, processing, transport and storage conditions of this commodity influence the species that are found. The understanding about population of fungi is essential for the development of viable strategies to control aflatoxins in organic Brazil nuts.

Colour stability of acrylic resin denture teeth after immersion in different beverages.

The colour stability of acrylic resin denture teeth in beverages was investigated. A spectrophotometer measured the colour (CIE-L*a*b* system) of all specimens after storage in distilled water/for 24 h at 37 degrees C (T0). Specimens were then immersed in various beverages. After 15 days (T1) and 30 days (T2), for each material, the mean deltaE values were calculated and compared by two-way ANOVA and Tukey intervals (alpha = 0.05). In the deltaT0T1 period, specimens stored in red wine were significantly discoloured, compared to distilled water (P = 0.003). There was no difference between immersion solutions in deltaET0T2 (P = 0.772) and in deltaET1T2 (P = 0.058), and no difference between materials in all immersion periods.

Chemical constituents and antifungal potential of Attalea geraensis Barb. Rodr. (Arecaceae) palm leaves, a species native to the Cerrado of Brazil.

Fungal diseases, especially those that affect the root systems of plants, caused by Rhizoctonia and Macrophomina are limiting factors for achieving high crop yields. Alternatives to controlling fungi with chemical products drive the search for new options for bioactive compounds from plants. Attalea geraensis, a palm tree from the Brazilian Cerrado, is rich in flavonoids with antifungal actions. The objective of this work is to identify the chemical classes present in the ethanolic extract of green leaves of A. geraensis and determine the antifungal potential of the extract against isolates of Macrophomina phaseolina (Tassi) Goid. and Rhizoctonia solani JG Kühn. Phytochemical prospection, flavonoid dereplication, and antifungal activity were carried out of the ethanolic extract of the green leaves of A. geraensis harvested in the Cerrado area of Brazil. Steroids, triterpenes, saponins, and anthraquinones are described here for the first time for the leaves of A. geraensis. The flavonoids quercetin, isorhamnetin, 3,7-dimethylquercetin, quercetin 3-galactoside, 5,7-dihydroxy-2-(4-hydroxy-3-methoxyphenyl)-3-{[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}-4H-chromen-4-one, rhamnazin 3-galactoside, keioside, and rhamnazin 3-rutinoside were identified. Of these, only quercetin and isorhamnetin had already been identified in the leaves of A. geraensis. The results show a fungistatic potential for the species. The diversity of flavonoids present in the leaves of A. geraensis may be the result of a synergistic action between fungus and plant or there could be an antagonistic effect between flavonoids and the other identified chemical classes.

Fungitoxic effect and phytochemical characteristics of Brazilian Cerrado weeds against Rhizoctonia solani and Macrophomina phaseolina fungi.

The use of natural products obtained from plants, for example, invasive plants, offers a variety of allelochemicals with fungicidal potential. With this in perspective, the objective was to evaluate the fungicidal potential of ethanolic extracts of Cerrado plants on Rhizoctonia solani and Macrophomina phaseolina. The ethanolic hydroalcoholic extract of the 12 plants identified as invaders in the Brazilian Cerrado was prepared (Anacardium humile Saint Hill; Baccharis dracunculifolia DC.; Cenchrus echinatus L; Commelina erecta L.; Erigeron bonariensis L.; Digitaria horizontalis Willd.; Digitaria insularis L.; Porophyllum ruderale Jacq. Cass; Richardia brasiliensis Gomes; Sida rhombifolia L.; Turnera ulmifolia L.; Smilax fluminensis Steud)) and phytochemical screening and determination of total phenols and flavonoids were performed. To evaluate the in vitro antifungal activity, the hydroalcoholic solutions at concentrations of 800, 1200, 1600, 2000, and 2400 µL 100 mL-1 were separately incorporated into BDA agar and poured into Petri dishes, followed by the mycelium disk of the fungus. As a control, two solutions were prepared, one ethanolic solution added to the BDA medium (2400 µg 100 mL-1) and the other with BDA medium only. They were poured into Petri dishes, followed by a 0.5 cm diameter disk of mycelium of the fungus, incubated (23±2 ºC), with a 24-hour photoperiod. Among the constituents found in the plants, 75% are phenolic compounds, 58.3% are cardiotonic heterosides, 50% are steroids, 33.3% are flavonoids, 16.7% are anthraquinones, and 8.3% are alkaloids, saponins, and reducing sugars. Out of the 12 species, only the extracts of C. erecta and R. brasiliensis were active for M. phaseolina and R. solani. Thus, it is concluded that the ethanolic extract of C. erecta has the fungicidal potential to control diseases caused by fungi that are soil inhabitants. Of the other species, A. humille, B. dracuncufolia, D. insulares, C. erecta, D. insulares, P. ruderale, and R. brasiliensis have natural fungitoxic potential because they stand out in the content of polyphenols efficient in reducing the mycelial growth of M. phaseolina and R. solani.

Early expression of the aflatoxin gene cluster in Aspergillus nomiae isolated from Brazil nut.

Aspergillus nomiae is the most important contaminant in Brazil nut due to its high incidence in these nuts and its strong production of carcinogenic metabolites: aflatoxins (AF). Aflatoxin biosynthesis pathway in A. nomiae is poorly studied. Thus, in present investigation, aflatoxin production and gene cluster (aflC, aflQ, aflU, and aflX) expression profile were evaluated on two strains of A. nomiae isolated from Brazil nut samples collected in the Amazon region, and cultivated on Brazil nut-based medium. The results showed that the expression of the aflatoxin gene cluster in A. nomiae, started at day 2 and occurred before the production of aflatoxins. Aflatoxin production (AFB1 and AFG1) was detected on day 3 on both strains. From day 4 onwards, all four toxins were detected and their production kept at similar proportions (AFG1>AFB1>AFG2>AFB2). Thus, the anticipated information obtained through early expression profile results of aflC, aflQ, aflU, and aflX gene cluster in A. nomiae may foresee aflatoxin production before its detection in Brazil nuts.

A non-toxigenic Aspergillus flavus strain prevents the spreading of Fusarium verticillioides and fumonisins in maize.

We evaluated Fusarium verticillioides and fumonisin contamination in maize samples after application of a non-aflatoxigenic Aspergillus flavus strain in the field. The sampling was performed 150 days after planting. The results showed a reduction in F. verticillioides frequency, as well as in fumonisin levels when samples were obtained from field areas treated with non-aflatoxigenic A. flavus strain. These results suggested a competition for substrate or space between fungi reducing the frequency of F. verticillioides and, consequently, fumonisin production.

Effects of gamma radiation on the growth of Alternaria alternata and on the production of alternariol and alternariol monomethyl ether in sunflower seeds.

The objective of the present study was to evaluate the effects of different gamma radiation doses on the growth of Alternaria alternata and on the production of toxins alternariol (AOH), and alternariol monomethyl ether (AME) in sunflower seed samples. After irradiation with 2, 5 and 7 kGy, the spore mass was resuspended in sterile distilled water and the suspension was inoculated into sunflower seeds. The number of colony-forming units per gram (CFU/g) was determined after culture on Dichloran Rose Bengal Chloramphenicol and Dichloran Chloramphenicol Malt Extract Agar. The presence of AOH and AME was investigated by liquid chromatography coupled to mass spectrometry. The radiation doses used resulted in a reduction of the number of A. alternata CFU/g and of AOH and AME levels when compared to the nonirradiated control group. Maximum reduction of the fungus (98.5%) and toxins (99.9%) was observed at a dose of 7 and 5 kGy, respectively. Under the present conditions, gamma radiation was found to be an alternative for the control of A. alternata and, consequently, of AOH and AME production in sunflower seeds.

Occurrence of deoxynivalenol and zearalenone in brewing barley grains from Brazil.

Barley (Hordeum vulgare L.) is an important cereal crop for food and represents one of the main ingredients in beer production. Considering the importance of barley and its derived products, the knowledge about the mycotoxin contamination in the barley production is essential in order to assess its safety. In this study, the levels of deoxynivalenol (DON) and zearalenone (ZEN) in brewing barley were determined using a LC-MS/MS method. A survey was conducted in 2015 to estimate the mycotoxin levels in these products (n = 76) from four crop regions in Brazil. The results showed high levels of DON and ZEN in the analyzed samples, with contamination levels of 94 and 73.6%, respectively. The mean levels of DON and ZEN ranged from 1700 to 7500 µg/kg and from 300 to 630 µg/kg, respectively. Barley samples from regions 1 and 2 presented higher levels of ZEN and DON, respectively, and those from region 4 presented lower levels of both. Co-occurrence of DON and ZEN was seen in the majority of the barley grain samples, and the mycotoxin content was above the maximum levels established by the Brazilian and European regulations.

Phytochemistry, antioxidant potential and antifungal of Byrsonima crassifolia on soil phytopathogen control.

The use of chemical defensives to control fungal diseases has by consequence to impact negatively over the environment and human health, this way, the use of plant extracts with antifungal properties along with proper cultural management makes viable an alternative plant production control, specially for familiar and organic cultures. The objective of this study was to perform phytochemical and antioxidant analysis of Byrsonima crassifolia (canjiqueira) barks and evaluate its antifungal potential over Fusarium solani and Sclerotinia sclerotiorum mycelial growth. The ethanol extract from plants collected in Pantanal, Mato Grosso do Sul, Brazil was submitted to phytochemical prospection, total phenol and flavonoids quantification and antioxidant activiy determination (DPPH). To evaluate antifungal activity concentrations of 800, 1200, 1600, 2000 and 2400 µg 100 mL-1 of ethanol extract were used. Which concentration was separately incorporated in agar (PDA) and shed in Petri dishes, followed by the fungi mycelial disc where the colonies diameter was measured daily. Negatives control with agar without extract and agar with an ethanol solution were used. The B. crassifolia ethanol extract presented inhibitory activity over the fungi studied where concentrations of 800 and 1600 µg 100 mL-1, inhibited 38% of the mycelial growth of F. solani; to S. sclerotiorum the best concentration was 2400 µg 100 mL1, reducing 37.5%. The antifungal bark extract potential of this specie is attributed to phenolic compounds and to triterpenes derivatives.

Effects of oral administration of aflatoxin B1 and fumonisin B1 in rabbits (Oryctolagus cuniculus).

The effects of prolonged oral administration (21 days) of fumonisin B(1) (FB(1)) and aflatoxin B(1) (AFB(1)) were studied in male New Zealand rabbits by clinical, pathological, biochemical and sphingolipid analyses. Twenty-four animals were randomly divided into the following four experimental groups: (A) 0 mg FB(1)+0 microg AFB(1)/(kg body weight(bw)day) (control); (B) 0 mg FB(1)+30 microg AFB(1)/(kg bw day); (C) 1.5 mg FB(1)/(kg bw day)+30 microg AFB(1)/(kg bw day); (D) 1.5 mg FB(1)/(kg bw day)+0 microg AFB(1). Animals from group B and principally from group C presented clinical signs of intoxication. Rabbits from group C presented a lower body weight gain than controls. Differences were observed between intoxicated rabbits and controls with respect to absolute and relative liver and kidney weight, hepatic function, serum urea and creatinine levels and Sa/So ratio. The most frequent hepatic and renal injuries were vacuolar degeneration of the liver and kidney as shown by the histopathological and serum biochemical results. Combined administration of AFB(1) and FB(1) resulted in synergistic toxic effects both in the liver and in the kidney, but hepatic injuries were more marked.

Effects of gamma radiation on maize samples contaminated with Fusarium verticillioides.

The efficacy of gamma-irradiation as a method of decontamination of maize containing Fusarium verticillioides under controlled conditions of relative humidity (RH) (97.5%) and water activity has been studied. Maize grains inoculated with a spore suspension of F. verticillioides were irradiated to 2, 5, and 10 kGy. Thereafter, the irradiated and control samples were analyzed for the presence of fumonisins, their viable cells were counted, and their morphology was investigated by electronic microscopy. It was found possible to decrease the risk of exposure to fumonisins by irradiating maize to 5 or 10 kGy. However, at the dose of 2 kGy, the survived fungi (36%) can produce more fumonisins than the fungi in the control unirradiated samples under the same conditions.

[Comparison between clinical and ultrasonographic measurements to estimate fetal weight during labor: a new clinical calculation formula]. / Comparación entre la medición clínica y ultrasonográfica para estimar el peso fetal en la fase activa del trabajo de parto: nueva fórmula para el cálculo clínico.

BACKGROUND: Fetal weight estimation is an important parameter in decision making during labor to avoid delivery complications. OBJECTIVES: To evaluate the reliability of clinical and ultrasonographic measurements in fetal weight estimation during active delivery, as well as to define which is the best method for calculate it. MATERIAL AND METHODS: Study of 115 healthy pregnant women during labor. Uterine fundus height, uterus wide and adipose panicle thickness, if it were so, were obtained. Fetal weight was calculated by means of Johnson's formula and a new one proposed (Carranza's formula). Also ultrasonographic estimation was done according to Hadlock 1. At birth, newborn's weight was documented and three groups were created according to newborn weight: < 2,500 g, 2,500 to 3,500 g and > 3,500 g. Differences among methods and real weight real were calculated by Student t test, and correlation between methods by Pearson's correlation analysis. RESULTS: There was a difference between real weight and Johnson's estimation (-104.8 +/- 289.4 g), Carranza's formula (+124.7 +/- 304.7 g), and ultrasonography (-102.0 +/- 299.6 g). Correlation between Carranza's and Johnson's formula was r = 0.796, between Carranza's formula and ultrasonography, r = 0.765, and between Johnson's formula and ultrasonography: r = 0.729 (p < 0.001). Carranza's formula has the lower variation regarding real weight. CONCLUSIONS: Clinical methods as well as ultrasonography were reliable methods to predict fetal weight with the advantage that clinical methods are more economic.

Effects of prolonged oral administration of aflatoxin B1 and fumonisin B1 in broiler chickens.

The effects of prolonged oral administration of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) mycotoxins were evaluated in broiler chickens from 21 to 42 d of age. A total of 192 birds were housed in experimental batteries and assigned to 32 cages, 6 birds per cage. The following treatments were applied: 1) 0 mycotoxins (control), 2) 10 mg of FB1, 3) 50 microg of AFB1, 4) 50 microg of AFB1 + 10 mg of FB1, 5) 350 microg of AFB1, 6) 350 microg of AFB1 + 10 mg of FB1, 7) 2,450 microg of AFB1, 8) 2,450 microg of AFB1 + 10 mg of FB1/kg of feed. Each treatment consisted of 4 replicates of 6 birds each. At the end of the trial, blood samples from 12 birds per treatment were collected, and the birds were necropsied. Compared with controls, the percentage of heterophils was lower (P < 0.05) in birds from groups receiving 50 microg of AFB1/kg + 10 mg of FB1/ kg and 2450 microg of AFB1/kg alone or in combination with FB1. A higher percentage of lymphocytes (P < 0.05) was observed in birds fed 50 microg of AFB1/kg + 10 mg of FB1/ kg, 350 microg of AFB1/kg, and 2,450 microg of AFB1/kg. A decrease in plasma albumin was observed only in birds fed 2,450 microg of AFB1/kg + 10 mg of FB1/kg. The liver of AFB1-treated birds had focal areas of necrosis and inflammatory infiltrates. In birds fed rations containing only 10 mg of FB1/kg, bile duct hyperplasia with fibrosis and a mononuclear infiltrate accompanied by trabecular derangement were observed. In contrast, in treatments in which FB1 was administered in combination, hepatic vacuolar degeneration was observed, and renal tissue presented corpuscles with increased cellular agglomeration, characterizing glomerulonephritis, and a clearly visible tubular epithelium with areas of degeneration and necrosis. The FB1 residues were detected in liver and in excreta of all FB1-treated groups, at levels that ranged from 0.013 to 0.051 mg/kg and from 1.19 to 2.79 mg/kg, respectively. Results indicated that FB1 and AFB1, singly or in combination at the levels evaluated, do not change markedly the hematological and serological parameters of broiler chickens, but may cause relevant lesions in liver and in kidneys.

Babesiosis (Babesia bovis) stability in unstable environments.

Enzootic stability (herd immunity) in bovine babesiosis occurs when the rate of transmission (inoculation rate) of Babesia spp by the tick vector is sufficient to immunize a majority of susceptible calves before the loss of calfhood resistance. The effect of three tick (Boophilus microplus) control strategies (none, threshold, and strategic) on enzootic stability and the likelihood of babesiosis (Babesia bovis) outbreaks was studied using a spreadsheet age-class computer simulation model. The model was driven by weekly bovine tick counts from Brazil and Uruguay. The Eldorado do Sul, RS, Brazil bovine population (30 degrees 05' South latitude) was found to be in a naturally occurring state of enzootic stability, corresponding to an inoculation rate exceeding 0.005 throughout the year. Threshold dipping strategies should not increase the risk of babesiosis in cattle so managed. Strategic dipping resulted in an extended period of enzootic instability lasting 30 weeks, which requires protection of the herd through immunization. Because of the more prolonged low winter temperature conditions, the Tacuarembó, Uruguay bovine population (31 degrees 40' South latitude) was found to be in a naturally occurring state of enzootic instability, characterized by a 28 week period in which the inoculation rate was below 0.005. Strategic dipping should lead to eradication of the babesial parasite from tick and bovine populations, but would not result in eradication of the tick vector. This could lead to subsequent outbreaks if Babesia carrier animals were to be introduced into the herd. In both populations, strategic tick control could be accompanied by concurrent babesiosis vaccination.

Robotic automated clean-up for detection of fumonisins B1 and B2 in corn and corn-based feed by high-performance liquid chromatography.

A high-performance liquid chromatography (HPLC) system with fluorescence detection and an automated on-line solid-phase extraction procedure for fumonisins B1 and B2 in corn and corn-based products is described. Different amounts of strong anion-exchange, C18 and end-capped C18 (C(18 ec)) silicas were tested for sample clean-up. Various HPLC parameters were analyzed. The best methodology was found to be extraction with acetonitrile-water and clean up on C(18 ec) disposable extraction cartridges. The system has the advantage of running in an unattended mode of operation and allows processing of 40 samples without system refuel, performing clean-up, o-phthaldialdehyde derivatization, injection and fumonisin detection by fluorescence detection linked to a computer integrator for automated data processing. Recoveries were performed with corn and corn-based feed samples (n=3) spiked with 0.1, 0.5, 1.0, 5.0 and 10 microg/g. Average recoveries for corn and corn-based feed were, respectively, 92.6 and 88.3% with relative standard deviations (RSDs) of 5.04 and 6.22%, for fumonisin B1 and 91.2 and 89.0% with RSDs of 5.84 and 7.88% for fumonisin B2. Detection limits (S/N=3) for corn and corn-based feed were approximately 0.03 microg/g for fumonisin B1 and 0.05 microg/g for fumonisin B2