Biomedical subjects

T D Phillips

Publications and source records attributed to T D Phillips.

At least 19 recordsLinked to original sources

PubMed2001

Development of porous clay-based composites for the sorption of lead from water.

Lead contamination of water is a major health hazard, as illustrated by the fact that exposure to this metal has been associated with death and disease in humans, birds, and animals. The present research was aimed at the development of a porous, solid-phase sorbent that can be used in the remediation of lead-contaminated water. A suitable sorbent was identified by screening various clays and other materials for their ability to effectively bind lead. The clay was adhered to a solid support using an aqueous solution of carboxymethyl cellulose. The binary composite was then tested for its ability to bind lead from solution, while providing void volume, increased surface area, and considerably enhanced hydraulic conductivity. The results suggested that a combination of sodium montmorillonite clay and carbon exhibited enhanced sorption of lead compared to carbon alone, and also supported the potential application of various combinations of sorbent materials. This value-added combination of clay, solid support, and adhesive will allow for the construction of column filtration systems that are multifunctional and capable of purifying large volumes of contaminated water.

Adsorption↗

PubMed2001

Evaluation of methods for predicting the toxicity of polycyclic aromatic hydrocarbon mixtures.

Risk assessments of polycyclic aromatic hydrocarbon mixtures are hindered by a lack of reliable information on the potency of both mixtures and their individual components. This paper examines methods for approximating the toxicity of polycyclic aromatic hydrocarbon (PAH) mixtures. PAHs were isolated from a coal tar and then separated by ring number using HPLC. Five fractions (A-E) were generated, each possessing a unique composition and expected potency. The toxicity of each fraction was measured in the Salmonella/mutagenicity assay and the Chick Embryo Screening Test (CHEST). Their abilities to induce ethoxyresorufin-O-deethylase and to inhibit gap junction intercellular communication in rat liver Clone 9 cells were also measured. In the Salmonella/mutagenicity assay, fractions were predicted to have potencies in the order C > D > E > B > A. Toxic equivalency factors (TEFs) for fractions A-E were in the order E > or = D > C > B > A. TEF values were 20,652, 20,929, 441, 306, and 74.1 micrograms of BaP equiv/g, respectively. A lack of agreement between assay-predicted potencies and chemical analysis-predicted potencies was observed with other assays and other methods of calculation. The results demonstrate the limitations of using a single method to predict the toxicity of a complex PAH mixture.

Animals↗

PubMed2001

Investigation of organophilic montmorillonite clay inclusion in zearalenone-contaminated diets using the mouse uterine weight bioassay.

Previous studies with low-pH montmorillonite (LPHM) clay exchanged with alkylammonium compounds showed that these organo clays were quite effective in sorbing the estrogenic mycotoxin zearalenone (ZEN) from aqueous solution. The potential toxicity of these types of clays, in particular hexadecyltrimethylammonium (HDTMA) LPHM, led to the investigation of the sorption efficacy of clay exchanged with a less toxic primary amine analog, hexadecylamine (HDA). Isothermal analysis studies showed that HDA LPHM was able to bind ZEN, but less effectively than HDTMA LPHM as evidenced by a significantly lower Freundlich K (63,900 vs. 845). The in vivo effectiveness of these two clays to bind ZEN was tested utilizing the mouse uterine weight bioassay. At a dietary inclusion level of 0.25%, the clays did not have a negative impact on overall animal health as measured by final body weight; however, they did not protect the animals from the estrogenic effects induced by 35 mg ZEN/kg in the feed (i.e., the uterine weights were not reduced in comparison to ZEN alone). In fact, the HDTMA LPHM group showed an increase in uterine weight that was more than the ZEN treatment group. When the animals were fed 0.5% clay, both exchanged clays (i.e., HDTMA LPHM and HDA LPHM) resulted in decreased body weight gain. The uterine weights of ZEN-fed animals (either alone or in combination with clays) were not significantly different from each other. In contrast, the uterine:body weight ratio showed a dramatic increase in the groups fed exchanged clay + ZEN compared to ZEN alone. These results suggest that alkylamine groups may assist the transport or uptake of ZEN and result in an enhanced toxicity from contaminated feed. The findings from this study clearly demonstrate the need for careful testing of all mycotoxin-binding agents before their inclusion in the diet.

Adsorption↗

PubMed2001

Deamination of fumonisin B(1) and biological assessment of reaction product toxicity.

Fumonisin B(1), a potent mycotoxin found in grain, has been resistant to degradation and detoxification by a variety of methods, including milling, fermentation, ammoniation, and ozonation. The primary amine of this compound contributes significantly to its toxicity; therefore, the major aim of this research was to remove this moiety via diazotization. In this study, fumonisin B(1) was deaminated in aqueous solution under conditions of acidic pH and low temperature (pH 1.0 and 5 degrees C) with the addition of NaNO(2). The concentration of fumonisin B(1) in the solution was analyzed by HPLC using o-phthaldialdehyde to derivatize the primary amine. Progress of the reaction was monitored as a loss of the derivatized peak as observed by HPLC with fluorescence detection. TLC analysis showed the disappearance of fumonisin B(1) following diazotization. Further, TLC displayed at least four reaction products that were not primary amines. Matrix-assisted laser desorption/ionization mass spectrometry coupled with time-of-flight analysis of the diazotization products also showed a diminished amount of authentic fumonisin B(1) and allowed identification of a product formed by the replacement of the primary amine with a hydroxyl group. The adult Hydra attenuata bioassay indicated a marked decrease in the toxicity of the products in comparison to parent fumonisin B(1). Optimization of this reaction could result in a rapid and practical method for the reclamation of fumonisin B(1)-contaminated feeds.

Animals↗

PubMed2000

Adsorption of Salmonella enteritidis by cetylpyridinium-exchanged montmorillonite clays.

Recent experiments in our laboratory have suggested that certain montmorillonite clays, when exchanged with the cationic surfactant cetylpyridinium (CP), may be useful in removing bacteria from aqueous solution. During an initial study, screening various CP-exchanged products for potential antibacterial activity, three CP-exchanged clays - CP*AAM (acid-activated montmorillonite), CP*STx-1 (Ca(++)-montmorillonite), and CP*SWy-2 (Na(+)-montmorillonite), proved to be the most effective. Binding studies were performed using 1mg each of CP-exchanged AAM, STx-1, and SWy-2 with a standardized Salmonella enteritidis solution containing approximately 40,000 colony forming units (CFU)/ml. The modified clays reduced bacterial numbers 98.1, 97.6, and 95.2%, respectively. In contrast, the parent clays only produced reductions of 39.8, 16.9, and 16.6%, respectively. Attempts were made to desorb CP from the modified clays by washing in sterile physiological saline for 24h. The resulting wash solutions failed to produce any significant reduction in bacterial colony counts; while, the washed clays retained their full antimicrobial activity. These findings suggested that the antibacterial effect of the clays is localized on the clay surface and is not due to CP dissociating from the clay. Electron microscopy revealed that the bacteria adhered to the surface of the CP-exchanged clays, but not the parent clays. Results from timed binding studies showed that the antibacterial effect was stable over the period observed. Rates of binding were positively influenced by increasing temperature, not affected by changes in pH, and negatively influenced by the presence of organic contaminants. The mechanism by which bacterial counts are reduced may involve the enhanced hydrophobicity and affinity of the CP-exchanged clay for Salmonella and the antibacterial activity of CP.

Adsorption↗

PubMed2000

G-protein signalling mediates differential production of toxic secondary metabolites.

Filamentous fungi elaborate a complex array of secondary metabolites, including antibiotics and mycotoxins. As many of these compounds pose significant economic and health concerns, elucidation of the underlying cellular mechanisms that control their production is essential. Previous work revealed that synthesis of the carcinogenic mycotoxins sterigmatocystin (ST) and aflatoxin (AF) in Aspergillus species is negatively controlled by FadA, the alpha-subunit of a heterotrimeric G-protein. In sharp contrast, we show here that the dominant activating fadA allele, fadAG42R, stimulates transcription of a gene from the A. nidulans penicillin (PN) gene cluster and elevates penicillin production. Thus, FadA has opposite roles in regulating the biosynthesis of a potent antibiotic (PN) and a lethal mycotoxin (ST) in A. nidulans. Furthermore, expression of fadAG42R in Fusarium sporotrichioides increases trichothecene (TR) mycotoxin production and alters TR gene expression. Our findings reveal that a G-protein defines an important control point for differential expression of fungal secondary metabolites within and across fungal genera. These data provide critical evidence suggesting that targeting G-protein signal transduction pathways as a means of controlling or preventing the production of a single mycotoxin could have serious undesirable consequences with regard to the production of other secondary metabolites.

Aspergillus nidulans↗

PubMed2000

Analysis of benzo[a]pyrene partitioning and cellular homeostasis in a rat liver cell line.

The uptake and subcellular partitioning of benzo[a]pyrene (BaP) were examined in a rat-liver cell line (Clone 9) using confocal and multiphoton microscopy. Following a 16-h treatment, intracellular accumulation of BaP increased with increasing concentration, and cytoplasmic BaP fluorescence reached saturation at 10 microM. Analysis of the kinetics of BaP uptake at this concentration indicated that BaP is rapidly partitioned into all cytoplasmic membranes within several min, although saturation was not reached until 4 h. Based upon the rapid uptake of BaP into membranes, the chronology of changes in gap junction-mediated intercellular communication (GJIC), plasma membrane potential (PMP), and steady state levels of intracellular Ca2+ in relation to the time-course for induction of microsomal ethoxyresorufin-0-deethylase (EROD) activity were examined. EROD activity in Clone 9 cells treated for 16 h increased with increasing concentrations of BaP and reached the highest levels at 40 microM BaP. In addition, kinetic analysis of EROD activity in Clone 9 cells treated with 10 microM BaP indicated that significant induction of EROD activity was not detected before 3 h, and it reached maximal levels by 16 h of treatment at this concentration. Both GJIC and PMP were directly affected by the partitioning of BaP into cellular membranes. The most sensitive index of BaP-induced changes in membrane function was GJIC which revealed a 25% suppression in cells exposed to 0.4 microM BaP for 16 h. Kinetic analysis revealed that suppression of GJIC occurred within 15 min of exposure of cells to 10 microM BaP, whereas significant suppression of PMP was not detected prior to 30-min exposure at this concentration. Elevation of basal Ca2+ level was also detected simultaneously with PMP at this dose. These data suggest that early changes in cellular membrane functions occur prior to detectable induction of EROD activity, although basal metabolic activation of BaP may contribute to these changes.

Animals↗

PubMed2000

Development and characterization of a carbon-based composite material for reducing patulin levels in apple juice.

Patulin, a heterocyclic lactone produced by various species of Penicillium and Aspergillus fungi, is often detected in apple juices and ciders. Previous research has shown the effectiveness of granular activated carbon for reducing patulin levels in aqueous solutions, apple juices, and ciders. In this study, ultrafine activated carbon was bonded onto granular quartz to produce a composite carbon adsorbent (CCA) with a high carbonaceous surface area, good bed porosity, and increased bulk density. CCA in fixed-bed adsorption columns was evaluated for efficacy in reducing patulin levels from aqueous solutions and apple juice. Columns containing 1.0, 0.5, and 0.25 g of CCA were continuously loaded with a patulin solution (10 microg/ml) and eluted at a flow rate of 1 ml/min. Results indicated that 50% breakthrough capacities for patulin on 1.0-, 0.5-, and 0.25-g CCA columns were 137.5, 38.5, and 19.9 microg, respectively. The effectiveness of CCA to adsorb patulin and prevent toxic effects was confirmed in vitro using adult hydra in culture. Hydra were sensitive to the effects of patulin, with a minimal affective concentration equal to 0.7 microg/ml; CCA adsorption prevented patulin toxicity until 76% breakthrough capacity was achieved. Fixed-bed adsorption with 1.0 g of CCA was also effective in reducing patulin concentrations (20 microg/liter) in a naturally contaminated apple juice, and breakthrough capacities were shown to increase with temperature. Additionally, CCA offered a higher initial breakthrough capacity than pelleted activated carbon when compared in parallel experiments. This study suggests that CCA used in fixed-bed adsorption systems effectively reduced patulin levels in both aqueous solutions and naturally contaminated apple juice; however, the appearance and taste of apple juice may be affected by the treatment process.

Adsorption↗

PubMed1999

Utilization of electrochemically generated ozone in the degradation and detoxication of benzo[a]pyrene.

The ability of electrochemically generated ozone (O3) to degrade and detoxify the polycyclic aromatic hydrocarbon (PAH) benzo[a]pyrene (BaP) was assessed utilizing the chick embryotoxicity screening test (CHEST) and Hydra attenuata bioassays. Aqueous solutions containing 10 microg/ml BaP and 0.5% (v/v) acetonitrile were subjected to ozonolysis for 0 to 30 min. Rapid degradation of BaP was evident by both gas chromatography/mass spectroscopy (GC/MS) and high-performance liquid chromatography (HPLC) analysis. HPLC fluorescence detection revealed no BaP shortly after 5 min of ozonolysis, while HPLC with PDA detection demonstrated continued reactions with ozone over the 30-min time course. As little as 2 min of O3 treatment afforded protection from BaP-induced mortality and toxicity (embryolethality and liver discoloration) in the chicken embryos. In the hydra bioassay, no toxicity was observed in the adult hydra until the ozonolysis products were reconstituted 100-fold from their initial post-ozonolysis concentrations. The results obtained from this study clearly demonstrate the potential application of electrochemically generated O3 for the detoxication and prevention of toxicity of BaP. Both CHEST and hydra assays predict that the ozonolysis products of BaP are less toxic than the parent compound.

Acetonitriles↗

PubMed1999

Assessment of the estrogenic effects of zearalenone after treatment with ozone utilizing the mouse uterine weight bioassay.

The ability of ozone gas (O3) to detoxify zearalenone (ZEN), a commonly occurring estrogenic mycotoxin, was assessed utilizing the mouse uterine weight bioassay. Solutions containing 12 ppm ZEN in water were ozonated for varying time periods (0, 0.5, and 5 min), then extracted with chloroform and evaporated to dryness. The residue was redissolved in acetonitrile and analyzed for ZEN. High-performance liquid chromatography (HPLC) analysis of aliquots indicated a rapid degradation and decline in parent ZEN level with increasing time of ozone treatment. The acetonitrile solution containing the degraded ZEN residue was added to a known volume of corn oil and evaporated under nitrogen to eliminate the acetonitrile in the oil. Eighteen-day-old prepubertal female mice (B6C3F1 strain) were gavaged daily with the test chemicals in 50 microl of corn oil between d 18 and 23. Initial dose-response studies showed that a concentration of 60 microg ZEN/mouse/d produced uterine weights that were significantly higher than the uterine weights of control animals (2.7 times higher than that of the solvent control). Treatment groups for the ozonation study included: DES, 0.1 microg (positive control), untreated ZEN (60 microg), extraction control for ZEN (60 microg), 0.5 min ozone-treated ZEN (60 microg), 5 min ozone-treated ZEN (60 microg), solvent control (50 microl), and absolute control. Results showed the uterine weights of animals receiving the ozone-treated ZEN were not significantly affected. These findings were in agreement with HPLC analyses and suggested that ozone can prevent the estrogenic effects of this important mycotoxin in mice. Importantly, ozone treatment of contaminated whole grains may enable the practical detoxification and control of ZEN. Also, the mouse uterine weight bioassay may be useful in assessing the efficacy of other detoxification strategies for estrogenic chemicals.

Animals↗

PubMed1999

Multi-bioassay approach for assessing the potency of complex mixtures of polycyclic aromatic hydrocarbons.

The chick embryotoxicity screening test (CHEST) and the Salmonella/microsome bioassay were used to evaluate embryotoxic and mutagenic endpoints from crude coal tar (CT) and its fractionated polycyclic aromatic hydrocarbon (PAH) mixtures (designated as A, B, C, D and E). In the CHEST assay, CT and PAH mixtures were injected into the egg yolk. A dose-dependent increase in embryo mortality was observed for all fractions. The E fraction resulted in 47% embryo mortality at a dose of 0.125 mg/kg and was more toxic than CT. At a dose of 1 mg/kg, 85-100% embryonic deaths occurred in fractions C and D and these two fractions were more potent than fractions A and B. The main visual toxic manifestations were liver lesions, discoloration of the liver, and edema. Both CT and fractionated PAH mixtures were also tested in the Salmonella/microsome plate incorporation assay with Salmonella typhimurium strain TA98 and were evaluated with and without metabolic activation at five dose levels. In the presence of S9, the CT and fractions C, D and E induced a dose-dependent positive response. Results from the Salmonella/microsome assay were in good agreement with findings from the CHEST assay suggesting that these two bioassays in combination may facilitate the rapid detection and ranking of complex PAH mixtures.

Animals↗

PubMed1999

Molecular characterization of high affinity, high capacity clays for the equilibrium sorption of ergotamine.

Ergot alkaloids (mycotoxins) produced by Claviceps and Neotyphodium species of fungi may contaminate animal feedstuffs and results in disease in livestock. In this study, diverse phyllosilicate clays and other adsorbent materials, differing in chemical and structural characteristics, were tested for their ability to sorb ergotamine, a prevalent ergot mycotoxin, from acidic solution. Results indicated minimal binding to those sorbents possessing low surface area, cation exchange capacity and inaccessible interlayer regions. Cetyl pyridinium-exchanged montmorillonite (organoclay) exhibited decreased propensity for ergotamine in acidic solution as compared with the unexchanged hydrophilic parent clay. The highest ergotamine sorption was observed with cation exchanged montmorillonite clays; whereas, when collapsed, these same clays sorbed very little ligand. Based on initial binding experiments, calcium and sodium montmorillonite clays were prioritized for further characterization, including: capacity, affinity, and heat (enthalpy) of adsorption. Computer models of energy-minimized ergotamine isomers and clay were used to illustrate possible mechanisms of ergot alkaloid sorption at interlayer sites. Additional studies are warranted to assess the stability of ergot alkaloid/clay complexes under alkaline conditions to further understand the mechanism of adsorption.

Adsorption↗

PubMed1999

Dietary clay in the chemoprevention of aflatoxin-induced disease.

Aflatoxins are harmful by-products of mold growth and, though invisible to the naked eye, are potentially fatal. The aflatoxin problem is long-standing and inextricable. Concerns about the aflatoxins originate from the strong implications of their involvement in disease and death in humans and animals, yet scientists and clinicians are still seeking ways to effectively deal with these dangerous and elusive chemicals. Safe, practical, and effective strategies for the detoxification of aflatoxin-contaminated food and feed are highly desirable. A simple and effective approach to the chemoprevention of aflatoxicosis has been to diminish or block exposure to aflatoxins via the inclusion of HSCAS clay in the diet. HSCAS clay acts as an aflatoxin enterosorbent that tightly and selectively binds these poisons in the gastrointestinal tract of animals, decreasing their bioavailability and associated toxicities. Further studies to delineate the molecular mechanisms of action have shown that the dicarbonyl system of aflatoxin is essential for tight binding by HSCAS. In these studies, adsorption data was fitted to multiple isotherm equations including the Langmuir, multi-Langmuir, general Freundlich, Langmuir-Freundlich, Toth and various transforms. Information derived included: the Gibbs standard free energy change of adsorption, enthalpy of adsorption, capacity, affinity, and heterogeneity coefficient. Computer modeling was also utilized to provide additional structural information and insight into the mechanism. Evidence suggests that aflatoxins may react at multiple sites on HSCAS particles, especially the interlayer region, but also at edges and basal surfaces. Since clay and zeolitic minerals comprise a broad family of functionally diverse chemicals, there may be significant hidden risks associated with their indiscriminate inclusion in the diet. All aflatoxin binding agents should be rigorously tested, paying particular attention to their effectiveness and safety in aflatoxin-sensitive animals and their potential for interactions with critical nutrients.

Aflatoxins↗

PubMed1998

Prevention of maternal and developmental toxicity in rats via dietary inclusion of common aflatoxin sorbents: potential for hidden risks.

In earlier work, we have reported that a phyllosilicate clay (HSCAS or NovaSil) can tightly and selectively bind the aflatoxins in vitro and in vivo. Since then, a variety of untested clay and zeolitic minerals have been added to poultry and livestock feeds as potential "aflatoxin binders." However, the efficacy and safety of these products have not been determined. A common zeolite that has been frequently added to animal feed is clinoptilolite. Our objectives in this study were twofold: (1) to utilize the pregnant rat as an in vivo model to compare the potential of HSCAS and clinoptilolite to prevent the developmental toxicity of aflatoxin B1 (AfB1), and (2) to determine the effect of these two sorbents on the metabolism and bioavailability of AfB1. Clay and zeolitic minerals (HSCAS or clinoptilolite) were added to the diet at a level of 0.5% (w/w) and fed to pregnant Sprague-Dawley rats throughout pregnancy (i.e., day 0 to 20). Treatment groups (HSCAS or clinoptilolite) alone and in combination with AfB1 were exposed to sorbents in the feed as well as by gavage. Untreated and AfB1 control animals were fed the basal diet without added sorbent. Between gestation days 6 and 13, animals maintained on diets containing sorbent were gavaged with corn oil in combination with an amount of the respective sorbent equivalent to 0.5% of the estimated maximum daily intake of feed. Animals receiving AfB1 were dosed orally (between days 6 and 13) with AfB1 (2 mg/kg body wt) either alone or concomitantly with a similar quantity of the respective sorbent. Evaluations of toxicity were performed on day 20. These included: maternal (mortality, body weights, feed intake, and litter weights), developmental (embryonic resorptions and fetal body weights), and histological (maternal livers and kidneys). Sorbents alone were not toxic; AfB1 alone and with clinoptilolite resulted in significant maternal and developmental toxicity. Animals treated with HSCAS (plus AfB1) were comparable to controls. Importantly, clinoptilolite (plus AfB1) resulted in severe maternal liver lesions (more severe than AfB1 alone), suggesting that this zeolite may interact with dietary components that modulate aflatoxicosis. In metabolism studies, adult male Sprague-Dawley rats, maintained on diets containing 0.5% (w/w) HSCAS or clinoptilolite, were dosed orally with 2.0 mg AfB1/kg body wt. The concentration of the major urinary metabolite (AfM1) was considerably decreased in the presence of HSCAS. These results suggest that the mechanism of protection of AfB1-induced maternal and developmental toxicities in the rat may involve adsorption and reduction of AfB1 bioavailability in vivo. Importantly, this study demonstrates the potential for significant hidden risks associated with the inclusion of nonselective aflatoxin binders in feeds. Aflatoxin sorbents should be rigorously tested individually and thoroughly characterized in vivo, paying particular attention to their effectiveness and safety in sensitive animal models and their potential for deleterious interactions.

Aflatoxin B1↗

PubMed1998

In vitro studies on the use of clay, clay minerals and charcoal to adsorb bovine rotavirus and bovine coronavirus.

Rotaviruses are the leading cause and coronaviruses are the major contributors of acute gastroenteritis in the young of various mammalian and avian species. Despite numerous trials and decades of research, vaccines have limited efficacy particularly for calves. As an alternative method of controlling infection, we have investigated broad spectrum antiviral agents that are not discriminatory among various viruses. This report involves testing a variety of adsorbent agents including charcoal, clay, and clay minerals to adsorb rotavirus and coronavirus in vitro. Results revealed that all the adsorbent agents had good to excellent capability of adsorbing rotavirus and excellent capability of adsorbing coronavirus. Percent adsorptions ranged from 78.74% to 99.89% for rotavirus and 99.99% for coronavirus; while sand (negative control) was < 0.01%. A high affinity binding was present as determined by a low percent desorption (0.06-3.09%). However, the adsorbent bound virus complex retained, and may have actually enhanced, infectivity.

Adsorption↗

PubMed1998

An in vitro study of theaflavins extracted from black tea to neutralize bovine rotavirus and bovine coronavirus infections.

Crude theaflavin was extracted from black tea and then fractionated by HPLC into five components (initial peaks (IP), TF1, TF2A, TF2B, and TF3). The crude extract and the various fractions of theaflavin were collected and tested, individually and in combination, for antirotaviral activity. The mean effective concentration (EC50) was calculated and compared. Activity varied from the most active being the uncharacterized theaflavin-like initial peaks (IP) with an EC50 of 0.125 microgram/ml to the least active being theaflavin-3 monogallate (TF2A) with an EC50 of 251.39 micrograms/ ml. The combination of TF1 + TF2A + TF2B + TF3 was more active than the sum of the activities of these four fractions individually, indicating synergism among the peaks. Only the crude extract was assayed for activity against coronavirus; the EC50 was 34.7 micrograms/ml.

Animals↗

PubMed1998

Aflatoxicosis in turkey poults is prevented by treatment of naturally contaminated corn with ozone generated by electrolysis.

Previous studies have demonstrated that a novel source of ozone gas (O3) maybe used to chemically degrade numerous mycotoxins, including aflatoxin (AF) B1. Subsequent in vitro analyses demonstrated detoxification of AFB1, suggesting a potential method of remediate AF-contaminated grain. The objective of this study was to evaluate the capability of electrochemically produced ozone to degrade AFB1 in naturally contaminated whole kernel corn and confirm detoxification in turkey poults. Corn was procured from the southern coastal areas of Texas and HPLC revealed 1,220 +/- 73.3 ppb AFB1. Control and contaminated corn were treated for 92 h with O3 at 200 mg/min in 30 kg batches; greater than 95% reduction of AFB1 in contaminated corn was achieved. One-day-old female turkey poults were fed 1) control corn, 2) control corn + O3, 3) AFB1 corn, or 4) AFB1 corn + O3 mixed in rations (46% by wt.) and consumed ad libitum for 3 wk. When compared with controls, turkeys fed AFB1 corn had reduced body weight gain and relative liver weight, whereas turkeys fed control corn + O3 or AFB1 corn + O3 did not differ from controls. Furthermore, alterations in the majority of relative organ weight, liver discoloration, serum enzyme activity, hematological parameters, and blood chemistry caused by AFB1 were eliminated (no difference from controls) by treatment with O3. These data demonstrate that treatment of contaminated corn with electrochemically produced O3 provided protection against AFB1 in young turkey poults. It is important to note that treatment of control corn with O3 did not alter the performance of the turkey poults.

Animal Feed↗

PubMed1997

Inhibition of 3,3',4,4',5-pentachlorobiphenyl-induced chicken embryotoxicity by 2,2',4,4',5,5'-hexachlorobiphenyl.

3,3',4,4',5-Pentachlorobiphenyl (pentaCB) caused a dose-dependent induction of chicken embryolethality, malformations, edema, and liver lesions at doses ranging from 0.5 to 12.0 microg/kg. In contrast, no embryotoxicity was observed after treatment with 10, 25, or 50 mg/kg 2,2',4,4',5,5'-hexaCB. In eggs cotreated with 2.0 microg/kg, 3,3',4,4',5-pentaCB plus 10, 25, or 50 mg/kg 2,2',4,4',5,5'-hexaCB, there was significant protection from 3,3',4,4',5-pentaCB-induced embryo malformations, edema, and liver lesions, whereas no inhibition of embryolethality was observed. These results further extend the response-specific nonadditive interactions of binary mixtures of polychlorinated biphenyls (PCBs) and should be considered in the development of approaches for hazard assessment of PCB mixtures and related compounds.

Abnormalities, Drug-Induced↗