Detoxification Compounds Research Articles

Nutritional and bioactive constituents and scavenging capacity of radicals in Amaranthus hypochondriacus

A. hypochondriacus leaves contained ample phytopigments including betalain, anthocyanin, β-xanthin, β-cyanin, and bioactive phytochemicals of interest in the industry of food. We have been evaluating the possibility of utilizing phytopigments of amaranth and bioactive constituents for making drinks. Therefore, we evaluated bioactive phytopigments and compounds including the potentiality of antioxidants in A. hypochondriacus leaves. A. hypochondriacus leaves have abundant protein, carbohydrates, and dietary fiber. We found considerable levels of inorganic minerals including magnesium, calcium, potassium (3.88, 3.01, 8.56 mg g−1), zinc, manganese, copper, iron (16.23, 15.51, 2.26, 20.57 µg g−1), chlorophyll b, chlorophyll ab chlorophyll a (271.08, 905.21, 636.87 μg g−1), scavenging capacity of radicals (DPPH, ABTS+) (33.46, 62.92 TEAC μg g−1 DW), total polyphenols (29.34 GAE μg g−1 FW), β-xanthin, betalain, β-cyanin (584.71, 1,121.93, 537.21 ng g−1), total flavonoids (170.97 RE μg g−1 DW), vitamin C, β-carotene, carotenoids (184.77, 82.34, 105.08 mg 100 g−1) in A. hypochondriacus leaves. The genotypes AHC6, AHC4, AHC11, AHC5, and AHC10 had a good scavenging capacity of radicals. Polyphenols, phytopigments, flavonoids, and β-carotene of A. hypochondriacus had potential antioxidant activity. Extracted juice of A. hypochondriacus can be an ample source of phytopigments and compounds for detoxification of reactive oxygen species (ROS) and attaining nutritional and antioxidant sufficiency.

Identification of Azoxystrobin Glutathione Conjugate Metabolites in Maize Roots by LC-MS.

Xenobiotic detoxification in plant as well as in animals has mostly been studied in relationship to the deactivation of the toxic residues of the compound that, surely for azoxystrobin, is represented by its β-methoxyacrylate portion. In maize roots treated for 96 h with azoxystrobin, the fungicide accumulated over time and detoxification compounds or conjugates appeared timewise. The main detoxified compound was the methyl ester hydrolysis product (azoxystrobin free acid, 390.14 m/z) thought to be inactive followed by the glutathione conjugated compounds identified as glutathione conjugate (711.21 m/z) and its derivative lacking the glycine residue from the GSH (654.19 m/z). The glycosylated form of azoxystrobin was also found (552.19 m/z) in a minor amount. The identification of these analytes was done by differential untargeted metabolomics analysis using Progenesis QI for label free spectral counting quantification and MS/MS confirmation of the compounds was carried out by either Data Independent Acquisition (DIA) and Data Dependent Acquisition (DDA) using high resolution LC-MS methods. Neutral loss scanning and comparison with MS/MS spectra of azoxystrobin by DDA and MSe confirmed the structures of these new azoxystrobin GSH conjugates.

Long-term effect of water diversion and CSOs on the remediation of heavy metals and microbial community in river sediments.

Untreated combined sewer overflows (CSOs) cause serious water pollution problems. In this study, the effects of CSO-induced heavy metals and the remediation practice of installation of a long-term water diversion (LTWD) on the microbial environment in river sediments were analyzed in an inland river. The Zn, Cd, Cr, and Cu contents in sediments and water were analyzed. DNA extraction and polymerase chain reaction analysis were conducted based on the Illumina MiSeq platform. The results showed that CSOs have a significant adverse impact on the diversity of microbial populations in river sediments. The LTWD is helpful in improving the richness of microorganisms and the proportion of Gram -ves, but it is challenging to reduce the accumulation of heavy metals in the sediment. The correlation analysis shows a strong relationship between some metabolic pathways and Zn and Cd accumulation in river sediments. Some detoxification compound metabolisms are also promoted at these sites. Thus, chronic exposure to environmental heavy metals from CSOs decreases the river microbial community, and further affects the ecological environment of the river. Therefore, without eliminating CSOs or reducing overflow frequency, it is difficult to alleviate the accumulation of heavy metals in river sediments and improve river ecology via water diversion alone.

Sulfide Intrusion and Detoxification in the Seagrass Zostera marina.

Gaseous sulfide intrusion into seagrasses growing in sulfidic sediments causes little or no harm to the plant, indicating the presence of an unknown sulfide tolerance or detoxification mechanism. We assessed such mechanism in the seagrass Zostera marina in the laboratory and in the field with scanning electron microscopy coupled to energy dispersive X-ray spectroscopy, chromatographic and spectrophotometric methods, and stable isotope tracing coupled with a mass balance of sulfur compounds. We found that Z. marina detoxified gaseous sediment-derived sulfide through incorporation and that most of the detoxification occurred in underground tissues, where sulfide intrusion was greatest. Elemental sulfur was a major detoxification compound, precipitating on the inner wall of the aerenchyma of underground tissues. Sulfide was metabolized into thiols and entered the plant sulfur metabolism as well as being stored as sulfate throughout the plant. We conclude that avoidance of sulfide exposure by reoxidation of sulfide in the rhizosphere or aerenchyma and tolerance of sulfide intrusion by incorporation of sulfur in the plant are likely major survival strategies of seagrasses in sulfidic sediments.

Dr Mittal and Colleagues Reply

To the Editor: We thank Dr Zamani for taking the time and interest to pose these important questions about our article.1 First, we would like to clarify that the article is based on a case report and is not a formal study. We will address the questions and concerns in the same order as received. “They have interestingly attributed the patient’s signs and symptoms to the contents of the detoxification kit.” Response: We merely established a temporal association between the consumption of the detoxification compound and the development of psychotic symptoms. We did not establish any causative associations. “They treated the patient with haloperidol and lorazepam.” Response: The patient was given haloperidol and lorazepam only in the emergency room once for agitation. The medications were not repeated during the patient’s stay on the inpatient unit. Also, 1 dose of haloperidol and lorazepam is unlikely to treat a patient with psychotic illness secondary to cannabis abuse. As we mentioned in the case report, the psychotic symptoms resolved after discontinuation of the detoxification compound without any treatment. “No side effects have been reported for proprietary blend.” Dr Zamani provides a reference for an acai berry product with a proprietary blend. Response: The proprietary blend is the undisclosed ingredients in any product. So, it would be unjustified to compare 2 different compounds with proprietary blends, which can very well be different. Our response is that we do not know what ingredients are included in the proprietary blend, so any comment on its effects or side effects could not be justified. Dr Zamani provides a statement about the side effects of creatine. Response: We provided references for isolated case reports of psychosis with consumption of large amounts of creatine. Dr Zamani has presented a review of the side effects of the ingredients of the detoxification compound. As mentioned in our article, we completed an extensive review of the ingredients using not only the information Web sites such as www.webmd.com and information sites for the respective compounds, but also case reports and any ongoing research about these compounds, with special focus on psychotic symptoms. “How do the authors know that his symptoms were not due to acute cannabis intoxication? Response: As we mentioned in the original article, cannabis intoxication has been shown to be only a component cause of psychosis.3 In our patient, the cannabis intoxication was chronic with no history of psychotic symptoms in the past. There was no family history of psychotic illness, and psychotic symptoms resolved within 2 to 3 days without using antipsychotics, except for the single dose of haloperidol. The patient denied any psychotic symptoms at a follow-up appointment 6 months after his hospitalization. On the basis of these facts, it is unlikely that his psychosis was a direct effect of acute cannabis intoxication.

Xanthurenic Acid Binds to Neuronal G-Protein-Coupled Receptors That Secondarily Activate Cationic Channels in the Cell Line NCB-20

Xanthurenic acid (XA) is a metabolite of the tryptophan oxidation pathway through kynurenine and 3-hydroxykynurenine. XA was until now considered as a detoxification compound and dead-end product reducing accumulation of reactive radical species. Apart from a specific role for XA in the signaling cascade resulting in gamete maturation in mosquitoes, nothing was known about its functions in other species including mammals. Based upon XA distribution, transport, accumulation and release in the rat brain, we have recently suggested that XA may potentially be involved in neurotransmission/neuromodulation, assuming that neurons presumably express specific XA receptors. Recently, it has been shown that XA could act as a positive allosteric ligand for class II metabotropic glutamate receptors. This finding reinforces the proposed signaling role of XA in brain. Our present results provide several lines of evidence in favor of the existence of specific receptors for XA in the brain. First, binding experiments combined with autoradiography and time-course analysis led to the characterization of XA binding sites in the rat brain. Second, specific kinetic and pharmacological properties exhibited by these binding sites are in favor of G-protein-coupled receptors (GPCR). Finally, in patch-clamp and calcium imaging experiments using NCB-20 cells that do not express glutamate-induced calcium signals, XA elicited specific responses involving activation of cationic channels and increases in intracellular Ca2+ concentration. Altogether, these results suggest that XA, acting through a GPCR-induced cationic channel modulatory mechanism, may exert excitatory functions in various brain neuronal pathways.

Combined exposure of Japanese quails to cyanotoxins, Newcastle virus and lead: Oxidative stress responses

Wild birds are continually exposed to many anthropogenic and natural stressors in their habitats. Over the last decades, mass mortalities of wild birds constitute a serious problem and may possibly have more causations such as natural toxins including cyanotoxins, parasitic diseases, industrial chemicals and other anthropogenic contaminants. This study brings new knowledge on the effects of controlled exposure to multiple stressors in birds. The aim was to test the hypothesis that influence of cyanobacterial biomass, lead and antigenic load may combine to enhance the effects on birds, including modulation of antioxidative and detoxification responses. Eight treatment groups of model species Japanese quail ( Coturnix coturnix japonica) were exposed to various combinations of these stressors. The parameters of detoxification and oxidative stress were studied in liver and heart after 30 days of exposure. The antioxidative enzymatic defense in birds seems to be activated quite efficiently, which was documented by the elevated levels and activities of antioxidative and detoxification compounds and by the low incidence of damage to lipid membranes. The greatest modulations of glutathione level and activities of glutathione-S-transferase, glutathione peroxidase, glutathione reductase, superoxide dismutase, catalase and lipid peroxidation were shown mostly in the groups with combined multiple exposures. The results indicate that the antioxidative system plays an important role in the protective response of the tissues to applied stressors and that its greater induction helps to protect the birds from more serious damage. Most significant changes of these “defense” parameters in case of multiple stressors suggest activation of this universal mechanism in situation with complex exposure and its crucial role in protection of the bird health in the environment.

Wheat Gene Expression is Differentially Affected by a Virulent Russian Wheat Aphid Biotype

An improved understanding of the complex interactions between plants and aphids is emerging. Recognition of aphid feeding in plant tissues involves production of several defense response signaling pathways and downstream production of defense and detoxification compounds. Feeding by Russian wheat aphid, Diuraphis noxia (Kurdjumov), a serious pest of cereal crops worldwide, induces foliar deformity and chlorophyll loss during compatible wheat-D. noxia interactions. Experiments described here revealed significant differences in level and pattern of gene expression in defense response signaling and metabolic pathways between compatible and incompatible D. noxia-wheat interactions. The jasmonate (JA)-signaling genes LOX, AOS, and AOC were significantly more upregulated (~3- to 7 fold) in incompatible interactions than in compatible interactions (~2.5 to 3.5 fold) as early as 1 h post D. noxia infestation (hpi). Cellulose synthase, responsible for strengthening plant cell walls via cellulose production, was also more upregulated in incompatible interactions (4 to 7 fold) than in compatible interactions (1 to 3.5 fold). In contrast, glycolysis and citric acid cycle genes were significantly downregulated (~1.5 to 2 fold) in incompatible interactions and upregulated or less downregulated in compatible interactions from 6 to 72 hpi. Differences in expression of JA-signaling genes between feeding site tissues and non-feeding site tissues suggest that D. noxia defense response signals in wheat are restricted primarily to aphid feeding sites in the initial 6 hpi. This is the first report of differential upregulation of plant genes at 1 hpi in incompatible interactions involving aphid herbivory. Early wheat plant defense responses in incompatible D. noxia interactions at 1, 3, and 6 hpi appear to be important aspects of D. noxia resistance in wheat.

Analysis of expressed sequence tags derived from a compatible Mycosphaerella fijiensis–banana interaction

Mycosphaerella fijiensis, a hemibiotrophic fungus, is the causal agent of black leaf streak disease, the most serious foliar disease of bananas and plantains. To analyze the compatible interaction of M. fijiensis with Musa spp., a suppression subtractive hybridization (SSH) cDNA library was constructed to identify transcripts induced at late stages of infection in the host and the pathogen. In addition, a full-length cDNA library was created from the same mRNA starting material as the SSH library. The SSH procedure was effective in identifying specific genes predicted to be involved in plant-fungal interactions and new information was obtained mainly about genes and pathways activated in the plant. Several plant genes predicted to be involved in the synthesis of phenylpropanoids and detoxification compounds were identified, as well as pathogenesis-related proteins that could be involved in the plant response against M. fijiensis infection. At late stages of infection, jasmonic acid and ethylene signaling transduction pathways appear to be active, which corresponds with the necrotrophic life style of M. fijiensis. Quantitative PCR experiments revealed that antifungal genes encoding PR proteins and GDSL-like lipase are only transiently induced 30days post inoculation (dpi), indicating that the fungus is probably actively repressing plant defense. The only fungal gene found was induced 37dpi and encodes UDP-glucose pyrophosphorylase, an enzyme involved in the biosynthesis of trehalose. Trehalose biosynthesis was probably induced in response to prior activation of plant antifungal genes and may act as an osmoprotectant against membrane damage.

Microarray analysis of genes affected by salt stress in tomato

Large-scale gene expression affected by salt stress was analyzed with tomato seedlings ( Lycoperson esculentum Mill cv. Money Maker) by a cDNA microarray (Tom1). The significantly differentially expressed genes (5% Benjamini-Hochberg false discovery rate) consisted of 1757 sequences in the analyzed tissues (cotyledons + shoot tip). Genes with over 2 fold difference were selected from the list and further categorized into different function and cellular processes. Tomato homologous genes for the chaperone proteins, antioxidant enzymes (catalase and peroxidase), and ion transporters (Na + - driven multidrug efflux pump, vacuolar ATPase, and others) were induced. The ACC oxidase and ethylene-responsive gene tomato homologs had higher transcript level after salt treatment. Multiple members with different expression patterns were identified for the bZIP, WRKY, and MADS-box transcription regulator. Different genes in the signal transduction pathway, such as the protein kinases (Shaggy kinase, mitogen-activated protein kinase, ethylene receptor neverripe, and others), protein phosphatases, calmodulin, G-protein, and the N- myristoyltransferase were regulated by salt stress. Most of the protease and the inhibitor homologs were suppressed by salt stress. In addition, different isoforms of cytochrome P450, genes for polyamine biosynthesis (putrescine and proline) and detoxification compounds (glutathione and thioredoxin), several key enzyme genes in the metabolic pathways of carbohydrates, amino acids, and fatty acids, were also affected by salt treatment. This study has provided a set of candidate genes, especially those in the regulatory machinery that can be further investigated to define salt stress in tomato and other plant species. Keywords: Antioxidants, cellular metabolism, cell wall, chaperonine, ethylene, protein kinase, tomato, transcription regulator, translation regulator, salt stress

Microarray analysis of genes affected by salt stress in tomato

Large-scale gene expression affected by salt stress was analyzed with tomato seedlings ( Lycoperson esculentum Mill cv. Money Maker) by a cDNA microarray (Tom1). The significantly differentially expressed genes (5% Benjamini-Hochberg false discovery rate) consisted of 1757 sequences in the analyzed tissues (cotyledons + shoot tip). Genes with over 2 fold difference were selected from the list and further categorized into different function and cellular processes. Tomato homologous genes for the chaperone proteins, antioxidant enzymes (catalase and peroxidase), and ion transporters (Na + - driven multidrug efflux pump, vacuolar ATPase, and others) were induced. The ACC oxidase and ethylene-responsive gene tomato homologs had higher transcript level after salt treatment. Multiple members with different expression patterns were identified for the bZIP, WRKY, and MADS-box transcription regulator. Different genes in the signal transduction pathway, such as the protein kinases (Shaggy kinase, mitogen-activated protein kinase, ethylene receptor neverripe, and others), protein phosphatases, calmodulin, G-protein, and the N- myristoyltransferase were regulated by salt stress. Most of the protease and the inhibitor homologs were suppressed by salt stress. In addition, different isoforms of cytochrome P450, genes for polyamine biosynthesis (putrescine and proline) and detoxification compounds (glutathione and thioredoxin), several key enzyme genes in the metabolic pathways of carbohydrates, amino acids, and fatty acids, were also affected by salt treatment. This study has provided a set of candidate genes, especially those in the regulatory machinery that can be further investigated to define salt stress in tomato and other plant species. Keywords: Antioxidants, cellular metabolism, cell wall, chaperonine, ethylene, protein kinase, tomato, transcription regulator, translation regulator, salt stress

Porphyrins and phthalocyanines as model compounds for detoxification of tumor chemotherapeutic drugs

The fluorescence behavior of porphyrins and phthalocyanines allows one to discriminate between monomeric and associated states of the dyes. These criteria are necessary prerequisites to decide about the inclusion behaviour of the dyes in oligomeric cyclodextrins. Masking the hydrophobic portion of the dyes by cyclodextrins allows one to transport these substances as inert through the body of an animal. The story is depicted here of how to proceed from functionalized porphyrinoids to tumor therapeutic drugs.