Practical methods to degrade mycotoxins using ozone gas (O
3) have been limited due to low O
3 production capabilities of conventional systems and their associated costs. Recent advances in ...electrochemistry (i.e. proton-exchange membrane and electrolysis technologies) have made available a novel and continuous source of O
3 gas up to 20% by weight. It is possible that the rapid delivery of high concentrations of O
3 will result in mycotoxin degradation in contaminated grains-with minimal destruction of nutrients. The major objectives of this study were to investigate the degradation and detoxification of common mycotoxins in the presence of high concentrations of O
3. In this study, aqueous equimolar (32 μM) solutions of aflatoxins B
1 (AfB
1), B
2 (AfB
2), G
1 (AfG
1), G
2 (AfG
2), cyclopiazonic acid (CPA), fumonisin B
1 (FB
1), ochratoxin A (OA), patulin, secalonic acid D (SAD) and zearalenone IZEN) were treated with 2, 10 and/or 20 weight% O
3 over a period of 5.0 min and analysed by HPLC. Results indicated that AfB
1 and AfG
1 were rapidly degraded using 2% O
3, while AfB
2 and AfG
2 were more resistant to oxidation and required higher levels of O
3 (20%) for rapid degradation. In other studies, patulin, CPA, OA, SAD and ZEN were degraded at 15 sec, with no by-products detectable by HPLC. Additionally, the toxicity of these compounds (measured by a mycotoxin-sensitive bioassay) was significantly decreased following treatment with O
3 for 15 sec. In another study, FB
1 (following reaction with O
3) was rapidly degraded at 15 sec, with the formation of new products. One of these appeared to be a 3-keto derivative of FB
1. Importantly, degradation of FB
1 did not correlate with detoxification, since FB
1 solutions treated with O
3 were still positive in two bioassay systems.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Penicillium paradoxum has an enigmatic Aspergillus-like anamorphic state; earlier named as Aspergillus paradoxus with a teleomorph state Hemicarpenteles paradoxus. The present paper describes the ...rediscovery of this species from India after five decades and includes a phylogenetic study of this strain. This is the first record of this strain from peninsular India including the Western Ghats.
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.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
The successful inclusion of hydrated sodium calcium aluminosilicate clay (HSCAS) in diets for the prevention of aflatoxicosis in animals has led to the investigation of other sorbents that bind ...mycotoxins. Unfortunately, in vitro studies are not always predictive of in vivo results. In the current study, three previously established in vitro methods: single-concentration sorption, isotherms and chemisorption index (
C
α) were compared as methods for predicting the adsorption of aflatoxin B
1 (AfB
1) from solution by four sorbents: HSCAS, charcoal, clinoptilolite and sand. In addition, a gastrointestinal (GI) model was utilized to measure adsorption. Finally, maize was included in modified isotherm studies to examine interactions. As supported by published in vivo studies, HSCAS proved efficacious in all testing methods (>99% bound in single-concentration and GI sorption studies,
C
α=0.89,
Q
max=0.26
mol
kg
−1). Binding of AfB
1 by charcoal was comparable to HSCAS (>99% bound in single-concentration and GI sorption studies,
C
α=0.78,
Q
max=0.889
mol
kg
−1) but was hindered in the presence of maize as seen by the distribution constant (
K
d=1.19×10
6 versus 1.11×10
5). Under GI conditions, clinoptilolite demonstrated catalytic activity not observed in the other methods. Results indicate that the GI model is a rapid and more physiologically relevant method of screening sorbents. A three-tiered system that includes: (1) an aqueous binding study; (2) a GI study and (3) isotherms (with and without matrix inclusion), may be used to prescreen mycotoxin/sorbent combinations more effectively before testing in animals.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Previous studies with cyclopiazonic acid (CPA) have indicated that this mycotoxin strongly adsorbs onto the surface of a naturally acidic phyllosilicate clay (AC). The objective of this study was to ...determine whether AC (and similar adsorbents) could protect against the toxicity of CPA in vivo. Acidic phyllosilicate clay, neutral phyllosilicate clay (NC, or hydrated sodium calcium aluminosilicate), and a common zeolite (CZ, or clinoptilolite) were evaluated. One-day-old broiler chicks consumed diets containing 0 or 45 mg/kg CPA alone or in combination with 1% AC, NC, or CZ ad libitum from Day 1 to 21. Body weight, feed consumption, feed:gain, hematology, serum biochemical values, and enzyme activities were evaluated. Compared to controls, CPA alone reduced body weight at Day 21 by a total of 26% and resulted in a significantly higher feed:gain ratio. Toxicity of CPA was also expressed through increased relative weights of kidney, proventriculus, and gizzard. Also, there were some alterations in hematology, serum biochemical values, and enzyme activities. Treatment with inorganic adsorbents did not effectively diminish the growth inhibitory effects of CPA or the increased weights of organs, although there was some protection from hematological, serum biochemical, and enzymatic changes produced by CPA. The results of this study suggest that in vitro binding of CPA to clay does not accurately forecast its efficacy in vivo; the reasons for this discrepancy are not clear, but they may be related to differences in clay binding capacity and ligand selectivity for CPA in vitro vs in vivo. Predictions about the ability of inorganic adsorbents to protect chickens from the adverse effects of mycotoxins should be approached with caution and should be confirmed in vivo, paying particular attention to the potential for nutrient interactions
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The phyllosilicate clay, hydrated sodium calcium aluminosilicate (HSCAS), has been shown to prevent aflatoxicosis in farm animals by reducing the bioavailability of aflatoxin. The present study was ...designed to determine the effects of HSCAS on the metabolism of aflatoxin B1 (AFB1) in an aflatoxin-sensitive species. Male Fischer-344 rats were orally dosed with 1.0, 0.5, 0.25 and 0.125 mg AFB1/kg body weight alone and in combination with 0.5% HSCAS. Urine samples were collected after 6, 24, 36, and 48 h. Aflatoxin M1 (AFM1) and aflatoxin P1 (AFP1) were detected in most urine samples, with or without HSCAS. AFM1 was found to be the major metabolite. Metabolite concentrations were significantly decreased in the presence of HSCAS, and more importantly, no additional metabolites were detected. Our results suggest that the AFB1-HSCAS complex was not significantly dissociated in vivo, and support earlier findings that HSCAS tightly binds aflatoxin.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The phyllosilicate clay, hydrated sodium calcium aluminosilicate (HSCAS), has been shown to prevent aflatoxicosis in farm animals by reducing the bioavailability of aflatoxin. The present study was ...designed to determine the effects of HSCAS on the metabolism of aflatoxin B
1 (afb
1) in an aflatoxin-sensitive species. Male Fischer-344 rats were orally dosed with 1.0, 0.5, 0.25 and 0.125 mg AFB
1/kg body weight alone and in combination with 0.5% HSCAS. Urine samples were collected after 6, 24, 36, and 48 h. Aflatoxin M
1 (AFP
1) and aflatoxin P
1 (AFP
1) were detected in most urine samples, with or without HSCAS. AFM
1 was found to be the major metabolite. Metabolite concentrations were significantly decreased in the presence of HSCAS, and more importantly, no additional metabolites were detected. Our results suggest that the AFB
1-HSCAS complex was not significantly dissociated in vivo, and support earlier findings that HSCAS tightly binds aflatoxin.
Administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, 20 micrograms/kg) to pregnant C57BL/6J mice (on day 10) resulted in 62% fetuses with cleft palate per litter without any observable ...maternal toxicity. In contrast, Aroclor 1254 administered at a dose of 750 mumol/kg was not teratogenic. Cotreatment of the pregnant mice with both Aroclor 1254 (244 mg/kg) and 2,3,7,8-TCDD (20 micrograms/kg) resulted in an 8.2% incidence of cleft palate per litter. In contrast, Aroclor 1254 did not afford any protection from the teratogenicity of dexamethasone in C57BL/6J mice. Previous studies have shown that Aroclor 1254 can act as a partial antagonist of the microsomal enzyme induction and immunotoxic effects of 2,3,7,8-TCDD in C57BL/6J mice and this paper demonstrates that the commercial polychlorinated biphenyl mixture also antagonizes 2,3,7,8-TCDD-mediated teratogenicity in this strain of mice.
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 histologjcal (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.
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