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Mercury (Hg), arsenic (As), cadmium (Cd), lead (Pb) and other toxic heavy metals (HM) pose significant risks to the environment, negatively impacting the morpho-physiological and biological traits of plants. At present, toxic elements constitute a significant proportion of the food chain, exerting an impact on human health due to their mobility and biomagnification. The metal exclusion biological technique stands out for its robust performance, even when dealing with extremely low metal concentrations. Its eco-friendly nature and cost-effectiveness further enhance its value. Due to the exponential growth pattern of bacteria, these exhibit high metal persistence and are recommended for metal exclusion processes. Moreover, vacuoles like vesicles present in mycorrhizal fungi can hold extremely high levels of HM. Microbe-assisted phytoremediation primarily occurs through two mechanisms: through the direct provision of the essential nutrients and phytohormones, such as plant growth regulators, siderophores, enzymes, and mineral; or indirectly by modulating the metal detoxification process. This indirect mechanism involves microbes aiding in the accumulation and sequestration of metals in plants through the secretion of specific extracellular substances like organic acids, biosurfactants, and chelators. Moreover, the metal bioavailability and translocation in the rhizosphere are also altered via various mechanisms like acidification, precipitation, complexation or redox reactions. The understanding of the molecular and physiological processes underpinning the functions of arbuscular mycorrhizal fungi (AMF) in reducing HM toxicity, improving plant performance by procuring nutrients under HM-toxicity has significantly improved in recent years. In this review, adaptive and persistent methods related to physiological and cross-protective mechanisms in bacteria and mycorrhizal fungi (MF) resulting from the evolutionary consequences of dealing with HM toxicity have been addressed. Furthermore, the article offers details on the physiological and molecular reactions of host plants with fungi, and bacteria to HM stress, which may be useful for unveiling new knowledge about the strategies of HMs remediation. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mycotoxins are a class of contaminants that pose serious harm to the safety of grains, food and animal feed, causing massive resource waste and severe economic loss. Zearalenone (ZEN) has been detected at high rates in moldy corn, wheat, and other grains, and exposure to ZEN pollution can induce reproductive, hepatic, and renal toxicity. Due to its widespread contamination and severe hazards, ZEN has become a major hidden danger to food safety. When traditional physical and chemical methods are used to degrade ZEN, there is a risk of secondary pollution. Therefore, food-related industries are always seeking biodegradation technologies with higher specificity, targeting capacity, safety, and adaptability. In this paper, the toxicity and harm of ZEN, microorganisms and enzymes that degrade ZEN, and the application of modern biotechnology in the removal of ZEN are reviewed with particular emphasis on the types of biodegradation products and the detoxification mechanism of ZEN, and potential directions for the application of ZEN are pointed out so as to provide a theoretical basis for further studies on biological detoxification of ZEN.

Introduction: Semiaphis heraclei is an important economic pest affecting Caprifoliaceae and Apiaceae plants, and chemical control is still the main effective control method in the field. Afidopyropen is a new type of pyridine cyclopropyl insecticide, which can effectively control piercing-sucking mouthparts pests and is suitable for pest resistance management. However, the detoxification mechanism of S. heraclei to afidopyropen is still poorly cleared. Methods: The insecticidal activity of afidopyropen against S. heraclei and the enzyme activity assay and synergism bioassay were evaluated. The detoxification enzyme genes were obtained by transcriptome and validated by quantitative real-time PCR (RT-qPCR). Furthermore, RNA interference was used to study the functions of detoxification enzyme genes. Results: The activities of cytochrome P450 monooxygenases (P450s) and carboxylesterases (CarEs) were significantly increased under afidopyropen treatment. The toxicity of afidopyropen against S. heraclei was significantly increased after application the inhibitors of piperonyl butoxide and triphenyl phosphate. Sixteen P450 genes and three CarE genes were identified in the transcriptome of S. heraclei. The RT-qPCR results showed that eleven P450 genes and two CarE genes were significantly upregulated under afidopyropen treatment, and the expression of CYP6DA2 and CarFE4 was upregulated by more than 2.5 times. The expression pattern of CYP6DA2 and CarFE4 was further analyzed in different developmental stages of S. heraclei and knockdown of CYP6DA2 and CarFE4 significantly increased the susceptibility of S. heraclei to afidopyropen. Conclusion: The results of this study uncover the key functions of CYP6DA2 and CarFE4 in the detoxification mechanism of S. heraclei to afidopyropen, and provide a theoretical basis for the scientific use of afidopyropen in the field. [ABSTRACT FROM AUTHOR]

To understand the physiological response mechanisms of Lymantria dispar larvae to heavy metal stress, their host, 2-year-old Larix olgensis seedlings grown in pots, were treated with three different concentrations of HgCl2 (Hg). Hg accumulation and tannin content in larch needles were measured. The growth and detoxification ability of the larvae were analyzed after being fed on the Hg-stressed needles. The results showed that Hg concentration in larch needles increased with Hg treatment concentration increase, while the tannin content decreased. The larval body mass was significantly decreased. The responses of the larval antioxidant and detoxifying enzymes to Hg stress appeared to differ, with the superoxide dismutase (SOD) and peroxidase (POD) activities in 4th instar larvae were significantly higher than CK. In contrast, the acid phosphatase (ACP), alkaline phosphatase (AKP) and glutathione S-transferase (GST) activities in 4th instar larvae were significantly lower than CK. This result indicated that Hg could inhibit the growth of larvae along the food chain. The larval antioxidant and detoxification enzymes produced adaptive responses to the Hg stress, which might partially alleviate the oxidative damages caused by Hg. [ABSTRACT FROM AUTHOR]

Abstract Background Fungal toxins are highly toxic and widely distributed, presenting a considerable threat to global agricultural development. Addressing the issue of aflatoxin B1 (AFB1) contamination in feed, it is crucial to ascertain the effectiveness and mechanisms of microbial strains in degradation. Results This study used isotope tracing and nuclear magnetic resonance (NMR) to investigate the degradation products of Bacillus amyloliquefaciens YUAD7 in complex substrates. By tracing 14C34-AFB1 and utilizing NMR, ultra-performance liquid chromatography–quadrupole time-of-flight/mass spectrometry (UPLC–Q-TOF/MS) purification and identification techniques, it was confirmed that AFB1 was degraded by YUAD7 into C12H14O4, C5H12N2O2, C10H14O2, and C4H12N2O, effectively removing 99.7% of AFB1 (100 μg/kg) from alfalfa silage. YUAD7 targeted the ester bond in the vanillin lactone ring structure, the ether bond in the furan ring structure, and the unsaturated carbon–carbon double bond in the furan ring structure during AFB1 degradation, disrupting the toxic sites responsible for AFB1's carcinogenic, teratogenic, and mutagenic effects and achieving biodegradation. Moreover, B. amyloliquefaciens YUAD7 transformed AFB1 through processes like hydrogenation, enzyme modification, and the loss of the -CO group while also being associated with metabolic pathways such as alanine, aspartate, glutamate metabolism, glutathione metabolism, cysteine and methionine metabolism, and pentose and glucuronate interconversions. Conclusions The utilization of isotope tracing allowed for rapid identification of degradation products in complex substrates, while NMR elucidated the structures of these products. This deepens our understanding of AFB1 biodegradation mechanisms, providing technical support for the practical application of these bacteria in degradation, and new insights into studying the biological degradation mechanism. B. amyloliquefaciens YUAD7 can be used as a potential strain for degrading AFB1 in large-scale silage. Graphical Abstract

Background: Fungal toxins are highly toxic and widely distributed, presenting a considerable threat to global agricultural development. Addressing the issue of aflatoxin B1 (AFB1) contamination in feed, it is crucial to ascertain the effectiveness and mechanisms of microbial strains in degradation. Results: This study used isotope tracing and nuclear magnetic resonance (NMR) to investigate the degradation products of Bacillus amyloliquefaciens YUAD7 in complex substrates. By tracing 14C34-AFB1 and utilizing NMR, ultra-performance liquid chromatography–quadrupole time-of-flight/mass spectrometry (UPLC–Q-TOF/MS) purification and identification techniques, it was confirmed that AFB1 was degraded by YUAD7 into C12H14O4, C5H12N2O2, C10H14O2, and C4H12N2O, effectively removing 99.7% of AFB1 (100 μg/kg) from alfalfa silage. YUAD7 targeted the ester bond in the vanillin lactone ring structure, the ether bond in the furan ring structure, and the unsaturated carbon–carbon double bond in the furan ring structure during AFB1 degradation, disrupting the toxic sites responsible for AFB1's carcinogenic, teratogenic, and mutagenic effects and achieving biodegradation. Moreover, B. amyloliquefaciens YUAD7 transformed AFB1 through processes like hydrogenation, enzyme modification, and the loss of the -CO group while also being associated with metabolic pathways such as alanine, aspartate, glutamate metabolism, glutathione metabolism, cysteine and methionine metabolism, and pentose and glucuronate interconversions. Conclusions: The utilization of isotope tracing allowed for rapid identification of degradation products in complex substrates, while NMR elucidated the structures of these products. This deepens our understanding of AFB1 biodegradation mechanisms, providing technical support for the practical application of these bacteria in degradation, and new insights into studying the biological degradation mechanism. B. amyloliquefaciens YUAD7 can be used as a potential strain for degrading AFB1 in large-scale silage. [ABSTRACT FROM AUTHOR]

IntroductionSemiaphis heraclei is an important economic pest affecting Caprifoliaceae and Apiaceae plants, and chemical control is still the main effective control method in the field. Afidopyropen is a new type of pyridine cyclopropyl insecticide, which can effectively control piercing-sucking mouthparts pests and is suitable for pest resistance management. However, the detoxification mechanism of S. heraclei to afidopyropen is still poorly cleared.MethodsThe insecticidal activity of afidopyropen against S. heraclei and the enzyme activity assay and synergism bioassay were evaluated. The detoxification enzyme genes were obtained by transcriptome and validated by quantitative real-time PCR (RT-qPCR). Furthermore, RNA interference was used to study the functions of detoxification enzyme genes.ResultsThe activities of cytochrome P450 monooxygenases (P450s) and carboxylesterases (CarEs) were significantly increased under afidopyropen treatment. The toxicity of afidopyropen against S. heraclei was significantly increased after application the inhibitors of piperonyl butoxide and triphenyl phosphate. Sixteen P450 genes and three CarE genes were identified in the transcriptome of S. heraclei. The RT-qPCR results showed that eleven P450 genes and two CarE genes were significantly upregulated under afidopyropen treatment, and the expression of CYP6DA2 and CarFE4 was upregulated by more than 2.5 times. The expression pattern of CYP6DA2 and CarFE4 was further analyzed in different developmental stages of S. heraclei and knockdown of CYP6DA2 and CarFE4 significantly increased the susceptibility of S. heraclei to afidopyropen.ConclusionThe results of this study uncover the key functions of CYP6DA2 and CarFE4 in the detoxification mechanism of S. heraclei to afidopyropen, and provide a theoretical basis for the scientific use of afidopyropen in the field.

This research aimed to address the issue of aflatoxin B1 (AFB1) contamination, which posed severe health and economic consequences. This study involved exploring unique species resources in the Qinghai-Tibet Plateau, screening strains capable of degrading AFB1. UPLC-Q-Orbitrap HRMS and NMR were employed to examine the degradation process and identify the structure of the degradation products. Results showed that Bacillus amyloliquefaciens YUAD7, isolated from yak dung in the Qinghai-Tibet Plateau, removed 91.7% of AFB1 from TSB-AFB1 medium with an AFB1 concentration of 10 µg/mL (72 h, 37°C, pH 6.8) and over 85% of AFB1 from real food samples at 10 µg/g (72 h, 37°C), exhibiting strong AFB1 degradation activity. Bacillus amyloliquefaciens YUAD7's extracellular secretions played a major role in AFB1 degradation mediated and could still degrade AFB1 by 43.16% after boiling for 20 min. Moreover, B. amyloliquefaciens YUAD7 demonstrated the capability to decompose AFB1 through processes such as hydrogenation, enzyme modification, and the elimination of the-CO group, resulting in the formation of smaller non-toxic molecules. Identified products include C12H14O4, C5H12N2O2, C10H14O2, C4H12N2O, with a structure consisting of dimethoxyphenyl and enoic acid, dimethyl-amino and ethyl carbamate, polyunsaturated fatty acid, and aminomethyl. The results indicated that B. amyloliquefaciens YUAD7 could be a potentially valuable strain for industrial-scale biodegradation of AFB1 and providing technical support and new perspectives for research on biodegradation products. [ABSTRACT FROM AUTHOR]

Nicosulfuron, an acetolactate synthase (ALS) inhibitor herbicide, is a broad-spectrum and highly effective post-emergence herbicide. Glycosyltransferases (GTs) are widely found in organisms and transfer sugar molecules from donors to acceptors to form glycosides or sugar esters, thereby altering the physicochemical properties of the acceptor molecule, such as participating in detoxification. In this study, nine glycosyltransferases in group D of the apple glycosyltransferase family I were predicted to possibly be involved in the detoxification metabolism of ALS-inhibiting herbicides based on gene chip data published online. In order to confirm this, we analysed whether the expression of the nine glycosyltransferase genes in group D was induced by the previously reported ALS-inhibiting herbicides by real-time PCR (polymerase chain reaction). It was found that the ALS-inhibiting herbicide nicosulfuron significantly increased the expression of the MdUGT73CG22 gene in group D. Further investigation of the mechanism of action revealed that the apple glycosyltransferase MdUGT73CG22 glycosylated and modified nicosulfuron both in vivo and ex vivo to form nicosulfuron glycosides, which were involved in detoxification metabolism. In conclusion, a new glycosyltransferase, MdUGT73CG22, was identified for the first time in this study, which can glycosylate modifications of the ALS-inhibiting herbicide nicosulfuron and may be involved in the detoxification process in plants, which can help to further improve the knowledge of the non-targeted mechanism of herbicides. [ABSTRACT FROM AUTHOR]

Gossypol is a yellow polyphenol naturally produced by Malvaceae plants such as cotton, which mainly exists in roots, stems, leaves, and seeds of cotton. Gossypol has animal toxicity, and long-term intake of gossypol will accumulate in livestock and cause poisoning, resulting in decreased fecundity, organ lesions, and even death of animals. The cotton output in Xinjiang is huge, accounting for more than 80% of the whole country. After cotton harvest, most of the waste cotton straws are directly crushed and returned to the field, resulting in great waste of resources. Cotton straw is rich in crude protein, cellulose, hemicellulose, and lignin, which is equivalent to common crop straw in nutritional components. However, its gossypol content exceeded the standard, which limited the application of cotton straw feed. How to achieve efficient and low-cost detoxification of gossypol has become the key factor to determining the fodder of cotton straw. The structure, properties, toxicity, detoxification technology, and detoxification mechanism of gossypol were summarized in this paper, which provided a reference for feed utilization of cotton straw. [ABSTRACT FROM AUTHOR]

T-2 toxin is one of the most widespread and toxic fungal toxins in food and feed. It can cause gastrointestinal toxicity, hepatotoxicity, immunotoxicity, reproductive toxicity, neurotoxicity, and nephrotoxicity in humans and animals. T-2 toxin is physicochemically stable and does not readily degrade during food and feed processing. Therefore, suppressing T-2 toxin-induced organ toxicity through antidotes is an urgent issue. Protective agents against the organ toxicity of T-2 toxin have been recorded widely in the literature, but these protective agents and their molecular mechanisms of detoxification have not been comprehensively summarized. In this review, we provide an overview of the various protective agents to T-2 toxin and the molecular mechanisms underlying the detoxification effects. Targeting appropriate targets to antagonize T-2 toxin toxicity is also an important option. This review will provide essential guidance and strategies for the better application and development of T-2 toxin antidotes specific for organ toxicity in the future.

This research aimed to address the issue of aflatoxin B1 (AFB1) contamination, which posed severe health and economic consequences. This study involved exploring unique species resources in the Qinghai-Tibet Plateau, screening strains capable of degrading AFB1. UPLC-Q-Orbitrap HRMS and NMR were employed to examine the degradation process and identify the structure of the degradation products. Results showed that Bacillus amyloliquefaciens YUAD7, isolated from yak dung in the Qinghai-Tibet Plateau, removed 91.7% of AFB1 from TSB-AFB1 medium with an AFB1 concentration of 10 μg/mL (72 h, 37°C, pH 6.8) and over 85% of AFB1 from real food samples at 10 μg/g (72 h, 37°C), exhibiting strong AFB1 degradation activity. Bacillus amyloliquefaciens YUAD7’s extracellular secretions played a major role in AFB1 degradation mediated and could still degrade AFB1 by 43.16% after boiling for 20 min. Moreover, B. amyloliquefaciens YUAD7 demonstrated the capability to decompose AFB1 through processes such as hydrogenation, enzyme modification, and the elimination of the -CO group, resulting in the formation of smaller non-toxic molecules. Identified products include C12H14O4, C5H12N2O2, C10H14O2, C4H12N2O, with a structure consisting of dimethoxyphenyl and enoic acid, dimethyl-amino and ethyl carbamate, polyunsaturated fatty acid, and aminomethyl. The results indicated that B. amyloliquefaciens YUAD7 could be a potentially valuable strain for industrial-scale biodegradation of AFB1 and providing technical support and new perspectives for research on biodegradation products.

Vegetables are crucial to a human diet as they supply the body with essential vitamins, minerals, etc. Heavy metals that accumulate in plants consequently enter the food chain and endanger people's health. Studying the spatial distribution and chemical forms of elements in plant/vegetable tissues is vital to comprehending the potential interactions between elements and detoxification mechanisms. In this study, leek plants and soil from vegetable gardens near lead–zinc mines were collected and cultivated with 500 mg L−1 PbNO3 solutions for three weeks. Micro X-ray fluorescence was used to map the distribution of Pb and other chemical elements in leek roots, and X-ray absorption near-edge spectroscopy was used to assess the Pb speciation in leek roots and leaves. These findings demonstrated that Pb, Cu, Mn, Cr, Ti and Fe were detected in the outer rings of the root's cross section, and high-intensity points were observed in the epidermis. Zn, K and Ca, on the other hand, were distributed throughout the root's cross section. Leek root and leaf contained significant quantities of lead phosphate and basic lead carbonate at more than 80%, followed by lead sulfide (19%) and lead stearate (11.1%). The capacity of leek roots to convert ambient lead into precipitated lead and fix it on the root epidermis and other inner surfaces is a key mechanism for reducing the toxic effects of Pb.

旨在为霉变花生粕中黄曲霉毒素B1（AFB1）的脱除提供技术支持，以自然霉变花生粕为实验材料，用二乙烯三胺脱除花生粕中的AFB1。采用单因素实验优化脱毒条件，并对二乙烯三胺脱除AFB1的机制进行研究。结果表明：二乙烯三胺脱除花生粕中AFB1的最佳工艺条件为液料比5∶ 1、处理温度50 ℃、处理时间45 min、二乙烯三胺溶液质量浓度10 mg/mL，在此条件下AFB1脱除率为95.5%；高效液相色谱和高分辨质谱分析表明，AFB1可能的降解机制是其酮羰基与二乙烯三胺发生脱水反应，并且反应产物通过离心随着上清液被脱除。二乙烯三胺具有应用于花生粕中AFB1脱除的潜力。To provide a technical support for the removal of aflatoxin B1 (AFB1) from moldy peanut meal, with naturally moldy peanut meal as the experimental material, and diethylenetriamine was used to the removal of AFB1.Single factor experiment was used to optimize the detoxification conditions, and the mechanism of removing AFB1 by diethylenetriamine was studied. The results showed that the optimal conditions for the removal of AFB1 from peanut meal were obtained as follows: liquid-solid ratio 5∶ 1, reaction temperature 50 ℃, reaction time 45 min, mass concentration of diethylenetriamine 10 mg/mL. Under these conditions, the detoxification rate was 95.5%. The high performance liquid chromatography and high-resolution mass spectrometry analysis showed that the possible degradation way of AFB1 was the dehydration reaction between the ketone carbonyl group in AFB1 and diethylenetriamine. In addition, in the process of detoxification, reaction products were removed by centrifugation with supernatant. In conclusion, diethylenetriamine has the potential to be used for the removal of AFB1 from peanut meal.

As a heavy metal, copper is toxic to aquatic organisms in water, causing oxidative stress and lipid deposition. However, there is currently no effective dietary strategy to prevent damage caused by copper exposure. Here, copper bioaccumulation, antioxidant enzymes, lipogenic enzymes, lipid metabolism-related gene expression levels and metabolic pathways were synthesized and evaluated in copper-exposed largemouth bass (Micropterus salmoides) after hydrolysis fish peptides (HFP) pretreatment. The results showed that supplementation with 1% (P

The rapid development of industrialization is causing several fundamental problems in plants due to the interaction between plants and soil contaminated with metallic nanoparticles (NPs). Numerous investigations have been conducted to address the severe toxic effects caused by nanoparticles in the past few decades. Based on the composition, size, concentration, physical and chemical characteristics of metallic NPs, and plant types, it enhances or lessens the plant growth at various developmental stages. Metallic NPs are uptaken by plant roots and translocated toward shoots via vascular system based on composition, size, shape as well as plant anatomy and cause austere phytotoxicity. Herein, we tried to summarize the toxicity induced by the uptake and accumulation of NPs in plants and also we explored the detoxification mechanism of metallic NPs adopted by plants via using different phytohormones, signaling molecules, and phytochelatins. This study was intended to be an unambiguous assessment including current knowledge on NPs uptake, accumulation, and translocation in higher plants. Furthermore, it will also provide sufficient knowledge to the scientific community to understand the metallic NPs-induced inhibitory effects and mechanisms involved within plants. [ABSTRACT FROM AUTHOR]

Nicosulfuron, an acetolactate synthase (ALS) inhibitor herbicide, is a broad-spectrum and highly effective post-emergence herbicide. Glycosyltransferases (GTs) are widely found in organisms and transfer sugar molecules from donors to acceptors to form glycosides or sugar esters, thereby altering the physicochemical properties of the acceptor molecule, such as participating in detoxification. In this study, nine glycosyltransferases in group D of the apple glycosyltransferase family I were predicted to possibly be involved in the detoxification metabolism of ALS-inhibiting herbicides based on gene chip data published online. In order to confirm this, we analysed whether the expression of the nine glycosyltransferase genes in group D was induced by the previously reported ALS-inhibiting herbicides by real-time PCR (polymerase chain reaction). It was found that the ALS-inhibiting herbicide nicosulfuron significantly increased the expression of the MdUGT73CG22 gene in group D. Further investigation of the mechanism of action revealed that the apple glycosyltransferase MdUGT73CG22 glycosylated and modified nicosulfuron both in vivo and ex vivo to form nicosulfuron glycosides, which were involved in detoxification metabolism. In conclusion, a new glycosyltransferase, MdUGT73CG22, was identified for the first time in this study, which can glycosylate modifications of the ALS-inhibiting herbicide nicosulfuron and may be involved in the detoxification process in plants, which can help to further improve the knowledge of the non-targeted mechanism of herbicides.

Rorippa sylvestris (L.) Besser. (yellow fieldcress) is a hyperaccumulator of cadmium (Cd) discovered recently. There are several studies in the topic of Cd tolerance capacity and detoxification mechanism of plants, but the detoxification mechanism of R. sylvestris is not clear. Root tiller seedlings of R. sylvestris were planted in the brown bottles filled with culture solution containing different levels of Cd (0, 10, 25, 50, 100, 200 μmol·L−1, respectively) for 8 days in order to make sure the physiological responses, Cd subcellular distribution and chemical forms under Cd stress. The results showed that the growth increased in lower Cd concentration and declined in higher Cd concentration. Physiological characteristics such as photosynthesis and MDA were not significantly affected compared with the control at Cd concentratetion ≤ 50 μmol·L−1. The content of soluble sugar and free proline increased with the increasing of Cd concentration for the purpose of reducing the Cd toxicity to plant. R. sylvestris had a strong capability of Cd accumulation in different Cd treatments. The concentration of Cd in plant tissues (root, stem, leaf) was in the order of root>stem>leaf. The Cd subcellular distribution in plant tissues of R. sylvestris was in the order of soluble fractions>cell wall>protoplast>mitochondria. Cd was mainly extracted by deionized water and 80% ethanol (60.91–69.76%), followed by sodium chloride (16.14–25.12%), which indicated that R. sylvestris achieved to enhance Cd tolerance capacity and detoxification mechanism through root retention and vacuolar compartmentalization.

Deoxynivalenol (DON) is a mycotoxin that contaminates animal feed and crops around the world. DON not only causes significant economic losses, but can also lead diarrhea, vomiting, and gastroenteritis in humans and farm animals. Thus, there is an urgent need to find efficient approaches for DON decontamination in feed and food. However, physical and chemical treatment of DON may affect the nutrients, safety, and palatability of food. By contrast, biological detoxification methods based on microbial strains or enzymes have the advantages of high specificity, efficiency, and no secondary pollution. In this review, we comprehensively summarize the recently developed strategies for DON detoxification and classify their mechanisms. In addition, we identify remaining challenges in DON biodegradation and suggest research directions to address them. In the future, an in-depth understanding of the specific mechanisms through which DON is detoxified will provide an efficient, safe, and economical means for the removal of toxins from food and feed. [ABSTRACT FROM AUTHOR]

Waterborne ammonia is becoming one of the most notorious pollutants in aquatic habitats and has been shown to induce a range of ecotoxicological effects on aquatic animals. High ammonia concentrations occur mainly in intensive aquaculture systems, and effective wastewater treatment and agricultural systems are necessary to treat excessive nitrogenous compounds. Ammonia can enter aquatic decapod crustaceans through their gills, thereby reducing the oxygen-carrying capacity of blood cells and damaging the structures of organs such as the gills and hepatopancreas. This ultimately results in oxidative stress, immunotoxicity, and high mortality. Crustaceans have the ability to exert detoxification functions against ammonia stress by regulating the permeation of ammonia and related nitrogenous compounds through membranes. To the best of our knowledge, a comprehensive review of the acute toxicity of ammonia to crustaceans is lacking. The present review focuses on the literature on the problems and mechanisms concerning ammonia-induced acute toxicity and aims to synthesize the knowledge of the relationship between ammonia stress and defense responses in crustaceans (mainly shrimp and crabs). This review also emphasizes the uptake, elimination, and detoxification of ammonia in crustaceans. [ABSTRACT FROM AUTHOR]

With the surrounding environment of Inner Mongolia lead (Pb) ore as the research background, the germination and physio-biochemical effects of Pb stress on alfalfa were discussed to employ this species for the remediation of Pb contaminated soil. Research has shown that a low Pb stress concentration could improve the biological resistance of alfalfa seeds, while a high Pb stress concentration cannot be tolerated. Interestingly, when the Pb concentration was 5 mg/L, the germination rate of the seed was promoted, and the chlorophyll content was especially increased. As the Pb content and stress increased, the amount of malondialdehyde (MDA), H2O2, catalase (CAT) increased; while the root cell viability, chlorophyll and soluble protein content decreased. In consequence, alfalfa was tolerant to Pb stress of 5 mg/L, inversely, its growth was inhibited at levels higher than 5 mg/L, and it was poisoned at 500 mg/L. Based on the principal component analysis (PCA), the H2O2, O2-, chlorophyll total, chlorophyll a, CAT and proline content explicitly reflected the change in the physiology on the alfalfa and its tolerance under Pb stress.

Remediation of environmental toxic pollutants has attracted extensive attention in recent years. Microbial bioremediation has been an important technology for removing toxic pollutants. However, microbial activity is also susceptible to toxicity stress in the process of intracellular detoxification, which significantly reduces microbial activity. Electroactive microorganisms (EAMs) can detoxify toxic pollutants extracellularly to a certain extent, which is related to their unique extracellular electron transfer (EET) function. In this review, the extracellular and intracellular aspects of the EAMs' detoxification mechanisms are explored separately. Additionally, various strategies for enhancing the effect of extracellular detoxification are discussed. Finally, future research directions are proposed based on the bottlenecks encountered in the current studies. This review can contribute to the development of toxic pollutants remediation technologies based on EAMs, and provide theoretical and technical support for future practical engineering applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Evaluating a novel fungal strain's pathogenicity to important pests and their involved immune responses may give crucial data on a broad scale for future use in pest management strategies. Date palms are mostly destroyed by invading populations of red palm weevils; thus, developing natural biopesticides for them requires a comprehensive screening program of plant secondary metabolites. In this research, we examined the pathogenicity of a new strain of Beauveria bassiana on an important agricultural pest, Rhynchophorus ferrugineus, by measuring the relative activity of defensive enzymes and detoxifying enzymes in certain larval instars. Our findings reveal that the B. bassiana strain may infect the instars of R. ferrugineus, and its pathogenicity to the larvae steadily increases as the spore concentration increases. Seven days after inoculation, the LC50 (the median lethal concentration) of B. bassiana was 490.42 × 105 and 2974.47 × 108 spores/mL for the second and fourth instar R. ferrugineus, respectively, and the LC50 of B. bassiana for each R. ferrugineus instar decreased with infection time, indicating a significant dose effect. Infected R. ferrugineus larvae of the second instars showed considerable changes in the activity of both protecting and detoxifying enzymes (peroxidase, catalase, superoxide dismutase, Cytochrome P450, glutathione S transferase (GST), and esterase) as infection time progressed. In addition, R. ferrugineus larvae that were infected with B. bassiana had enzyme activity that persisted from 24 to 48 h, which was much longer than in the control group. Lethality of B. bassiana resulted in elevated expressions of GST, Esterase, and Cytochrome P450 responsive genes. In conclusion, the results of this research indicate that B. bassiana may be utilized as a bio-insecticide to suppress young larvae of R. ferrugineus in an integrated pest management program. [ABSTRACT FROM AUTHOR]

The wide applications of nanoparticles increased the demand for their risk assessment, a number of studies on the diverse effects of nanoparticles on various systems have been published. This review provides an overview of the mechanisms of cellular uptake of nanoparticles (NPs) and the advanced toxicological studies of the nanoparticles of metals and metal oxides on various systems (in-vitro and in-vivo).

The effect of calcium (Ca)–cadmium (Cd) interactions on the plant Cd bioaccumulation process may be closely related to the ecological Ca/Cd stoichiometry in the substrate. However, owing to the complexity of plant absorption, accumulation mechanisms and influencing factors, the mechanism of Ca-mediated Cd bioaccumulation and Cd tolerance in Capsicum is still unclear. In this study, the bioaccumulation, subcellular distribution and chemical forms of Cd in Capsicum were analysed via pot experiments to reveal the Ca-mediated Cd bioaccumulation process and its detoxification mechanism under different Ca/Cd stoichiometric ratios. The results revealed that an increase in the substrate Ca/Cd ratio promoted the accumulation of Cd in the roots; restricted the transport of Cd to the stems, leaves and peppers; and promoted the accumulation of Cd in the aboveground leaves but decreased its accumulation in edible parts. Cd was enriched mainly in the cell wall and cell-soluble fraction in each tissue and was enriched in only 1 %–13 % of the organelles. The accumulation of Cd in the cell wall and cell-soluble fractions of roots treated with different Ca concentrations increased by 56.57 %–236.98 % and 64.41 %–442.14 %, respectively. The carboxyl, hydroxyl and amino groups on the root cell wall play important roles in binding and fixing Cd2+. Moreover, the increase in the Ca content also increased the proportion of pectin and protein-bound Cd (F- NaCl), insoluble phosphate-bound Cd (F- C) and insoluble oxalate-bound Cd (F- HCl) in the roots, stems and leaves and reduced the proportion of highly active chemical forms such as inorganic acid salt-bound Cd (F- E) and water-soluble phosphate-bound Cd (F- W). Our study revealed that the bioaccumulation of Cd in Capsicum was influenced by the Ca/Cd ratio and that Ca could alleviate Cd stress by regulating the subcellular distribution and chemical form ratio of Cd in different tissues where the cell wall plays an important role in Cd tolerance and detoxification. [Display omitted] • Ca promoted the accumulation of Cd in roots and reduced its transfer ability. • The subcellular distribution and chemical form were important to reduce Cd toxicity. • Ca adjusted the chemical form of Cd and decreased the activity of Cd. • Ca promoted the immobilization of Cd by cell wall and soluble components of cells. • Cd in cell wall was mainly held by pectin and cellulose, and regulated by Ca. [ABSTRACT FROM AUTHOR]

Cadmium (Cd), a non-essential element for plant, is a ubiquitous and highly toxic heavy metal, seriously endangering agricultural production and human health. As a nonedible economic crop, cotton (Gossypium hirsutum L.) has great potential in remediation of Cd contaminated soil, but its underlying mechanism is still unknown. Melatonin (MT), as a plant growth regulator, is involved in alleviating Cd toxicity in some plants, but the molecular mechanisms of MT-mediated Cd detoxification in cotton are largely unknown. This study investigated the possible molecular mechanisms of the MT-mediated Cd detoxification in cotton seedlings by comparative transcriptomic and metabolomic analyses. The results showed that the cotton seedlings were dwarfed and the leaves were wilted and yellow under Cd stress. The application of 50 μmol L-1 MT significantly increased the superoxide dismutase (SOD) activity and malondialdehyde (MDA) content under Cd stress, but 100 μmol L-1 MT significantly decreased SOD activity, while increased ascorbate peroxidase (APX) activity significantly. The addition of 100 mmol L-1 MT significantly increased Cd concentration in the shoots and roots under Cd stress. RNA-seq analysis showed that 5573, 7105, 7253, 25, 198, 9 up-regulated and 6644, 7192, 7404, 9, 59, 0 down-regulated differentially expressed genes (DEGs) were identified in the comparisons of CK vs T1, CK vs T2, CK vs T3, T1 vs T2, T1 vs T3 and T2 vs T3, respectively. It was revealed that MT promoted the expression of certain related genes under Cd stress, and the effect of 100 μmol L-1 MT was better. Moreover, UPLC-MS/MS widely targeted metabolites analyses showed that 195, 150, 150, 12, 24, 59 up-regulated and 16, 11, 23, 38, 127, 66 down-regulated differentially accumulated metabolites (DAMs) were changed in the CK vs T1, CK vs T2, CK vs T3, T1 vs T2, T1 vs T3 and T2 vs T3, respectively. It was revealed that MT induced the synthesis of alkaloids and flavonoids, and inhibited or reduced the synthesis of lipids, amino acids and their derivatives. The comprehensive analyses of transcriptomic and metabolic data showed that 33 DEGs and 4 DAMs, 46 DEGs and 16 DAMs, and 1 DEGs and 1 DAMs were dominantly involved in the pathways of valine, leucine and isoleucine degradation, ABC transporter, alpha-linolenic acid metabolism, respectively. It was revealed that there were three major mechanisms involved in MT-mediated Cd detoxification in cotton, including the enhancement of antioxidant capacity regulated by APX, flavonoids and alkaloids; accumulation of secondary metabolites related to Cd chelation, such as amino acids and derivatives; and regulation of cadmium ion transportation, such as ABC transporter activation. In conclusion, this study provides new insights into the MT-mediated Cd stress response. [ABSTRACT FROM AUTHOR]

Cadmium (Cd), as one of the heavy metals with biological poisonousness, seriously suppresses plant growth and does harm to human health. Hence, phytoremediation was proposed to mitigate the negative effects from Cd and restore contaminated soil. However, the internal mechanisms of detoxification of Cd used in phytoremediation are not completely revealed. In this study, we cloned the cytochrome P450 gene PscCYP716A1 from hybrid poplar "Chuanxiang No. 1" and found that the PscCYP716A1 was transcriptionally upregulated by Cd stress and downregulated by the exogenous brassinolide (BR). Meanwhile, PscCYP716A1 significantly promoted the poplar growth and enhanced the Cd accumulation in poplar. Compared to wild-type poplars, overexpressed PscCYP716A1 lines produced higher levels of endogenous BR and showed a stronger tolerance to Cd, which revealed that PscCYP716A1 may reduce the oxidative stress damage induced by Cd stress through accelerating BR synthesis. In general, PscCYP716A1 has a potential superiority in regulating the plant's tolerance to Cd stress, which will provide a scientific basis and a new type of gene-modified poplar for Cd-pollution remediation. [ABSTRACT FROM AUTHOR]

Abstract Background It has been reported that nitric oxide (NO) could ameliorate cadmium (Cd) toxicity in tall fescue; however, the underlying mechanisms of NO mediated Cd detoxification are largely unknown. In this study, we investigated the possible molecular mechanisms of Cd detoxification process by comparative transcriptomic and metabolomic approaches. Results The application of Sodium nitroprusside (SNP) as NO donor decreased the Cd content of tall fescue by 11% under Cd stress (T1 treatment), but the Cd content was increased by 24% when treated with Carboxy-PTIO (c-PTIO) together with Nitro-L-arginine methyl ester (L-NAME) (T2 treatment). RNA-seq analysis revealed that 904 (414 up- and 490 down-regulated) and 118 (74 up- and 44 down-regulated) DEGs were identified in the T1 vs Cd (only Cd treatment) and T2 vs Cd comparisons, respectively. Moreover, metabolite profile analysis showed that 99 (65 up- and 34-down- regulated) and 131 (45 up- and 86 down-regulated) metabolites were altered in the T1 vs Cd and T2 vs Cd comparisons, respectively. The integrated analyses of transcriptomic and metabolic data showed that 81 DEGs and 15 differentially expressed metabolites were involved in 20 NO-induced pathways. The dominant pathways were antioxidant activities such as glutathione metabolism, arginine and proline metabolism, secondary metabolites such as flavone and flavonol biosynthesis and phenylpropanoid biosynthesis, ABC transporters, and nitrogen metabolism. Conclusions In general, the results revealed that there are three major mechanisms involved in NO-mediated Cd detoxification in tall fescue, including (a) antioxidant capacity enhancement; (b) accumulation of secondary metabolites related to cadmium chelation and sequestration; and (c) regulation of cadmium ion transportation, such as ABC transporter activation. In conclusion, this study provides new insights into the NO-mediated cadmium stress response.

The wide applications of nanoparticles increased the demand for their risk assessment, a number of studies on the diverse effects of nanoparticles on various systems have been published. This review provides an overview of the mechanisms of cellular uptake of nanoparticles (NPs) and the advanced toxicological studies of the nanoparticles of metals and metal oxides on various systems (in-vitro and in-vivo). [ABSTRACT FROM AUTHOR]

Environmental pollution and energy scarcity have promoted the development of renewable alternative energy of rice straw-based bioethanol. However, the production of main fermentation inhibitors from the pretreatment of rice straw raw material reduces the bioethanol yield. In order to improve bioethanol production, a waste biomass-based adsorbent (AEPA 250) was used to adsorb three main inhibitors of ferulic acid, vanillin, and furfural from the rice straw hydrolysate in this study. The adsorption percentages were calculated using the high-performance liquid chromatography method. The results showed that the adsorption percentages of three inhibitors were all above 70% in 10 min, demonstrating the efficient detoxification of AEPA 250 on rice straw hydrolysate. The adsorption contributions related to the attribute features of three inhibitors and AEPA 250 were evaluated for the first time. The density functional theory calculations and AEPA 250 characterizations were used to obtain these attribute parameters. Analysis of the correlation heat map between adsorption efficiencies and attribute features of AEPA 250 (or fermentation inhibitors) indicated that AEPA 250 possessed the lower activation energy (E a) and pre-exponential factor (A) when it was prepared, as well as fermentation inhibitors had the higher ionization constant (pKa) and lower electrophilicity index (ω), resulting in the enhancement of bioethanol production. The contribution of pKa was greater than A followed by Ea and ω for adsorption process. Meanwhile, the key metabolic pathways involved in central carbon metabolism were analyzed for AEPA 250 detoxification using proteomics method. The results indicated that the up-regulation of SDH3, ACO1, CIT2 and MLS1 (or down-regulation of SCT1) genes contributed to inhibitors detoxification using AEPA 250 , which effectively provided more nicotinamide adenine dinucleotide (NADH) for the reduction of these inhibitors. This study explores the detoxification mechanisms at the molecular level for boosting bioethanol production in the future, which lays the foundation for the development of efficient adsorbents and resistant engineering strains. [Display omitted] • Three inhibitors of ferulic acid, vanillin and furfural were detoxified by AEPA 250. • The contribution of pKa was greater than A followed by E a for inhibitors adsorption. • Central carbon metabolic pathways provided more NADH to enhance bioethanol yield. • SDH3, ACO1, CIT2, MLS1, and SCT1 genes related to inhibitors detoxification. [ABSTRACT FROM AUTHOR]

Combined pollutions of arsenic (As) and copper (Cu) are common in water bodies near mines, non-ferrous metal smelting and power plants. This study investigated the effect of Cu(II) on the absorption and speciation of As(V) by microalgae. We compared the absorption and speciation of arsenic by microalgae (mainly Cyanophyta and Chlorophyta) when exposed to single As(V) with that exposed to As-Cu co-exposure in laboratory. The results showed that in the case of single As(V) exposure, the inhibitory effect of As(V) on microalgae was primarily affected by the exposure time, instead of the concentration of As(V) in the water solution. Compared with single As(V) exposure, the presence of Cu(II) under As-Cu co-exposure promoted the absorption and accumulation of As(V) by algae. The combination effect of As and Cu on algae was antagonistic instead of synergistic within the tolerance range of algae to them. In the presence of Cu(II), more monomethylarsonous acid (MMA) and dimethylarsinous acid (DMA), which are volatile organic arsenic compounds, were produced in algae compared with the control. The finding that Cu(II) can mediate the absorption and speciation processes of arsenic in algae has significance in possible bioremediation of arsenic pollution in aquatic environment.

The yellow stem borer (YSB), Scirpophaga incertulas, is a prominent pest in rice cultivation causing serious yield losses. The larval stage is an important stage in YSB, responsible for maximum infestation. However, limited knowledge exists on the biology and mechanisms underlying the growth and differentiation of YSB. To understand and identify the genes involved in YSB development and infestation, so as to design pest control strategies, we performed de novo transcriptome analysis at the first, third, fifth, and seventh larval developmental stages employing Illumina Hi-seq. High-quality reads (HQR) of ∼229 Mb were assembled into 24,775 transcripts with an average size of 1485 bp. Genes associated with various metabolic processes, i.e., detoxification mechanism [CYP450, GSTs, and carboxylesterases (CarEs)], RNA interference (RNAi) machinery (Dcr-1, Dcr-2, Ago-1, Ago-2, Sid-1, Sid-2, Sid-3, and Sid-1-related gene), chemoreception (CSPs, GRs, OBPs, and ORs), and regulators [transcription factors (TFs) and hormones] were differentially regulated during the developmental stages. Identification of stage-specific transcripts made it possible to determine the essential processes of larval development. Comparative transcriptome analysis revealed that YSB has not evolved much with respect to the detoxification mechanism, but showed the presence of distinct RNAi machinery. The presence of strong specific visual recognition coupled with chemosensory mechanisms supports the monophagous nature of YSB. Designed expressed sequenced tags-simple-sequence repeats (EST-SSRs) will facilitate accurate estimation of the genetic diversity of YSB. This is the first report on characterization of the YSB transcriptome and the identification of genes involved in key processes, which will help researchers and industry to devise novel pest control strategies. This study also opens up a new avenue to develop next-generation resistant rice using RNAi or genome editing approaches.

Patulin (PAT) is a mycotoxin produced by Penicillium species, which often contaminates fruit and fruit-derived products, posing a threat to human health and food safety. This work aims to investigate the detoxification of PAT by Kluyveromyces marxianus YG-4 ( K. marxianus YG-4) and its application in apple juice. The results revealed that the detoxification effect of K. marxianus YG-4 on PAT includes adsorption and degradation. The adsorption binding sites were polysaccharides, proteins, and some lipids on the cell wall of K. marxianus YG-4, and the adsorption groups were hydroxyl groups, amino acid side chains, carboxyl groups, and ester groups, which were combined through strong forces (ion interactions, electrostatic interactions, and hydrogen bonding) and not easily eluted. The degradation active substance was an intracellular enzyme, and the degradation product was desoxypatulinic acid (DPA) without cytotoxicity. K. marxianus YG-4 can also effectively adsorb and degrade PAT in apple juice. The contents of organic acids and polyphenols significantly increased after detoxification, significantly improving the quality of apple juice. The detoxification ability of K. marxianus YG-4 toward PAT would be a novel approach for the elimination of PAT contamination.

Survival of organisms in polluted habitats is a key factor regarding their long-term population persistence. To avoid harmful physiological effects of pollutants' accumulation in organisms, decontamination and excretion could be effective mechanisms. Among invertebrates, ground beetles are reliable indicators of environmental pollution. Published results, however, are inconsistent, as some studies showed effective decontamination and excretion of pollutants, while others demonstrated severe toxic symptoms due to extreme accumulation. Using ground beetles as model organisms, we tested our pollution intensity-dependent disposal hypothesis for five pollutants (Cd, Cu, Mn, Pb, and Zn) among four soil pollution intensity levels (low, moderate, high, and extreme) by categorical meta-analysis on published data. According to our hypothesis, decontamination and excretion of pollutants in ground beetles are effective in lowly or moderately polluted habitats, while disposal is ineffective in highly or extremely polluted ones, contributing to intense accumulation of pollutants in ground beetles. In accordance with the hypothesis, we found that in an extremely polluted habitat, accumulation of Cd and Pb in ground beetles was significantly higher than in lowly polluted ones. These findings may suggest the entomoremediation potential of ground beetles in an extremely polluted environment. [ABSTRACT FROM AUTHOR]

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Mycotoxin contamination causes significant economic loss to food and feed industries and seriously threatens human health. Aflatoxins (AFs) are one of the most harmful mycotoxins, which are produced by Aspergillus flavus, Aspergillus parasiticus, and other fungi that are commonly found in the production and preservation of grain and feed. AFs can cause harm to animal and human health due to their toxic (carcinogenic, teratogenic, and mutagenic) effects. How to remove AF has become a major problem: biological methods cause no contamination, have high specificity, and work at high temperature, affording environmental protection. In the present research, microorganisms with detoxification effects researched in recent years are reviewed, the detoxification mechanism of microbes on AFs, the safety of degrading enzymes and reaction products formed in the degradation process, and the application of microorganisms as detoxification strategies for AFs were investigated. One of the main aims of the work is to provide a reliable reference strategy for biological detoxification of AFs.

We investigated changes in mineral nutrient uptake and translocation and photosystem II (PSII) functionality, in the hyperaccumulator Noccaea caerulescens after exposure to 800 μM Zn in hydroponic culture. Exposure to Zn inhibited the uptake of K, Mn, Cu, Ca, and Mg, while the uptake of Fe and Zn enhanced. Yet, Ca and Mg aboveground tissue concentrations remain unchanged while Cu increased significantly. In the present study, we provide new data on the mechanism of N. caerulescens acclimation to Zn exposure by elucidating the process of photosynthetic acclimation. A spatial heterogeneity in PSII functionality in N. caerulescens leaves exposed to Zn for 3 days was detected, while a threshold time of 4 days was needed for the activation of Zn detoxification mechanism(s) to decrease Zn toxicity and for the stomatal closure to decrease Zn supply at the severely affected leaf area. After 10-day exposure to Zn, the allocation of absorbed light energy in PSII under low light did not differ compared to control ones, while under high light, the quantum yield of non-regulated energy loss in PSII (ΦNO) was lower than the control, due to an efficient photoprotective mechanism. The chlorophyll fluorescence images of non-photochemical quenching (NPQ) and photochemical quenching (qP) clearly showed spatial and temporal heterogeneity in N. caerulescens exposure to Zn and provided further information on the particular leaf area that was most sensitive to heavy metal stress. We propose the use of chlorophyll fluorescence imaging, and in particular the redox state of the plastoquinone (PQ) pool that was found to display the highest spatiotemporal heterogeneity, as a sensitive bio-indicator to measure the environmental pressure by heavy metals on plants. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the chromium (Cr) detoxification mechanism-induced changes in growth and antioxidant defence enzyme activities in Chrysopogon zizanioides. Plant growth decreased by 36.8% and 45.0% in the shoots and roots, respectively, in the 50 mg/L Cr treatment. Cr accumulation was higher in root (9807 μg/g DW) than in shoots (8730 μg/g DW). Photosynthetic pigments and malondialdehyde content increased up to the 30 mg/L Cr treatment, whereas they declined at higher doses. The activity of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) were increased significantly with increasing of Cr dose but slightly declined at higher doses. Isozyme banding patterns revealed the expression of multiple bands for SOD, CAT and POX enzymes, and the band intensity decreased at high doses of Cr exposure. These results indicate that higher Cr doses increased the oxidative stress by over production of reactive oxygen species (ROS) in vetiver that had potential tolerance mechanism to Cr as evidenced by enhanced level of antioxidative enzymes, photosynthetic pigments, MDA contents. Therefore, vetiver has evolved a mechanism for detoxification and accumulates higher concentration of toxic Cr. This study provides a better understanding of how vetiver detoxifies Cr. [ABSTRACT FROM AUTHOR]