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Kirsten Benkendorff - One of the best experts on this subject based on the ideXlab platform.

  • Volatile and bioactive compounds in opercula from Muricidae molluscs supports their use in ceremonial incense and traditional medicines
    Scientific Reports, 2017
    Co-Authors: Bijayalakshmi Devi Nongmaithem, David Rudd, Peter Mouatt, Joshua Smith, Michael Russell, Caroline Sullivan, Kirsten Benkendorff
    Abstract:

    Muricidae molluscs are the source of a valuable purple dye that was traded as a luxury item in the Mediterranean region and by the late Byzantine was reserved for royalty and priests. Less well known is the use of muricid opercula in sacred incense and traditional medicines, although they are still used as rare ingredients today. This study provides the first chemical assessment of opercula from Muricidae, based on several traditional preparation procedures. Chemical analysis of opercula smoke revealed aromatic phenols, which act as fragrance stabilisers and produce a “medicinal” odour. Analysis of lipid extracts revealed pharmaceutically active compounds, including brominated indoles, Choline Esters and adenosine, consistent with their traditional medical applications. Depending on the preparation procedures, toxic pyridine was also detected. ICP-MS analysis of muricid opercula shows the presence of essential macro and microelements, as well as metals, some of which exceed the recommended safe levels for human use. Nevertheless, these findings support the Muricidae as an historically important marine resource, providing Biblical dyes, medicines and perfume. The opercula contains biologically active compounds and produces smoke containing volatile scent compounds, consistent with their identification as the most likely source of onycha, a controversial ingredient in sacred incense.

  • Transcriptome of the Australian Mollusc Dicathais orbita Provides Insights into the Biosynthesis of Indoles and Choline Esters
    MDPI AG, 2016
    Co-Authors: Abdul Baten, Ajit Kumar Ngangbam, Daniel L. E. Waters, Kirsten Benkendorff
    Abstract:

    Dicathais orbita is a mollusc of the Muricidae family and is well known for the production of the expensive dye Tyrian purple and its brominated precursors that have anticancer properties, in addition to Choline Esters with muscle-relaxing properties. However, the biosynthetic pathways that produce these secondary metabolites in D. orbita are not known. Illumina HiSeq 2000 transcriptome sequencing of hypobranchial glands, prostate glands, albumen glands, capsule glands, and mantle and foot tissues of D. orbita generated over 201 million high quality reads that were de novo assembled into 219,437 contigs. Annotation with reference to the Nr, Swiss-Prot and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases identified candidate-coding regions in 76,152 of these contigs, with transcripts for many enzymes in various metabolic pathways associated with secondary metabolite biosynthesis represented. This study revealed that D. orbita expresses a number of genes associated with indole, sulfur and histidine metabolism pathways that are relevant to Tyrian purple precursor biosynthesis, and many of which were not found in the fully annotated genomes of three other molluscs in the KEGG database. However, there were no matches to known bromoperoxidase enzymes within the D. orbita transcripts. These transcriptome data provide a significant molecular resource for gastropod research in general and Tyrian purple producing Muricidae in particular

  • Mass spectrometry imaging reveals new biological roles for Choline Esters and Tyrian purple precursors in muricid molluscs
    Scientific Reports, 2015
    Co-Authors: David Rudd, Maurizio Ronci, Martin R. Johnston, Taryn Guinan, Nicolas H. Voelcker, Kirsten Benkendorff
    Abstract:

    Despite significant advances in chemical ecology, the biodistribution, temporal changes and ecological function of most marine secondary metabolites remain unknown. One such example is the association between Choline Esters and Tyrian purple precursors in muricid molluscs. Mass spectrometry imaging (MSI) on nano-structured surfaces has emerged as a sophisticated platform for spatial analysis of low molecular mass metabolites in heterogeneous tissues, ideal for low abundant secondary metabolites. Here we applied desorption-ionisation on porous silicon (DIOS) to examine in situ changes in biodistribution over the reproductive cycle. DIOS-MSI showed muscle-relaxing Choline ester murexine to co-localise with tyrindoxyl sulfate in the biosynthetic hypobranchial glands. But during egg-laying, murexine was transferred to the capsule gland and then to the egg capsules, where chemical ripening resulted in Tyrian purple formation. Murexine was found to tranquilise the larvae and may relax the reproductive tract. This study shows that DIOS-MSI is a powerful tool that can provide new insights into marine chemo-ecology.

  • are the traditional medical uses of muricidae molluscs substantiated by their pharmacological properties and bioactive compounds
    Marine Drugs, 2015
    Co-Authors: Kirsten Benkendorff, David Rudd, Bijayalakshmi Devi Nongmaithem, Lei Liu, Fiona Young, Vicki Edwards, Catharine Avila, Catherine A Abbott
    Abstract:

    Marine molluscs from the family Muricidae hold great potential for development as a source of therapeutically useful compounds. Traditionally known for the production of the ancient dye Tyrian purple, these molluscs also form the basis of some rare traditional medicines that have been used for thousands of years. Whilst these traditional and alternative medicines have not been chemically analysed or tested for efficacy in controlled clinical trials, a significant amount of independent research has documented the biological activity of extracts and compounds from these snails. In particular, Muricidae produce a suite of brominated indoles with anti-inflammatory, anti-cancer and steroidogenic activity, as well as Choline Esters with muscle-relaxing and pain relieving properties. These compounds could explain some of the traditional uses in wound healing, stomach pain and menstrual problems. However, the principle source of bioactive compounds is from the hypobranchial gland, whilst the shell and operculum are the main source used in most traditional remedies. Thus further research is required to understand this discrepancy and to optimise a quality controlled natural medicine from Muricidae.

  • Solvent Separating Secondary Metabolites Directly from Biosynthetic Tissue for Surface-Assisted Laser Desorption Ionisation Mass Spectrometry
    MDPI AG, 2015
    Co-Authors: David Rudd, Kirsten Benkendorff, Nicolas H. Voelcker
    Abstract:

    Marine bioactive metabolites are often heterogeneously expressed in tissues both spatially and over time. Therefore, traditional solvent extraction methods benefit from an understanding of the in situ sites of biosynthesis and storage to deal with heterogeneity and maximize yield. Recently, surface-assisted mass spectrometry (MS) methods namely nanostructure-assisted laser desorption ionisation (NALDI) and desorption ionisation on porous silicon (DIOS) surfaces have been developed to enable the direct detection of low molecular weight metabolites. Since direct tissue NALDI-MS or DIOS-MS produce complex spectra due to the wide variety of other metabolites and fragments present in the low mass range, we report here the use of “on surface” solvent separation directly from mollusc tissue onto nanostructured surfaces for MS analysis, as a mechanism for simplifying data annotation and detecting possible artefacts from compound delocalization during the preparative steps. Water, ethanol, chloroform and hexane selectively extracted a range of Choline Esters, brominated indoles and lipids from Dicathais orbita hypobranchial tissue imprints. These compounds could be quantified on the nanostructured surfaces by comparison to standard curves generated from the pure compounds. Surface-assisted MS could have broad utility for detecting a broad range of secondary metabolites in complex marine tissue samples

David Rudd - One of the best experts on this subject based on the ideXlab platform.

  • Volatile and bioactive compounds in opercula from Muricidae molluscs supports their use in ceremonial incense and traditional medicines
    Scientific Reports, 2017
    Co-Authors: Bijayalakshmi Devi Nongmaithem, David Rudd, Peter Mouatt, Joshua Smith, Michael Russell, Caroline Sullivan, Kirsten Benkendorff
    Abstract:

    Muricidae molluscs are the source of a valuable purple dye that was traded as a luxury item in the Mediterranean region and by the late Byzantine was reserved for royalty and priests. Less well known is the use of muricid opercula in sacred incense and traditional medicines, although they are still used as rare ingredients today. This study provides the first chemical assessment of opercula from Muricidae, based on several traditional preparation procedures. Chemical analysis of opercula smoke revealed aromatic phenols, which act as fragrance stabilisers and produce a “medicinal” odour. Analysis of lipid extracts revealed pharmaceutically active compounds, including brominated indoles, Choline Esters and adenosine, consistent with their traditional medical applications. Depending on the preparation procedures, toxic pyridine was also detected. ICP-MS analysis of muricid opercula shows the presence of essential macro and microelements, as well as metals, some of which exceed the recommended safe levels for human use. Nevertheless, these findings support the Muricidae as an historically important marine resource, providing Biblical dyes, medicines and perfume. The opercula contains biologically active compounds and produces smoke containing volatile scent compounds, consistent with their identification as the most likely source of onycha, a controversial ingredient in sacred incense.

  • Mass spectrometry imaging reveals new biological roles for Choline Esters and Tyrian purple precursors in muricid molluscs
    Scientific Reports, 2015
    Co-Authors: David Rudd, Maurizio Ronci, Martin R. Johnston, Taryn Guinan, Nicolas H. Voelcker, Kirsten Benkendorff
    Abstract:

    Despite significant advances in chemical ecology, the biodistribution, temporal changes and ecological function of most marine secondary metabolites remain unknown. One such example is the association between Choline Esters and Tyrian purple precursors in muricid molluscs. Mass spectrometry imaging (MSI) on nano-structured surfaces has emerged as a sophisticated platform for spatial analysis of low molecular mass metabolites in heterogeneous tissues, ideal for low abundant secondary metabolites. Here we applied desorption-ionisation on porous silicon (DIOS) to examine in situ changes in biodistribution over the reproductive cycle. DIOS-MSI showed muscle-relaxing Choline ester murexine to co-localise with tyrindoxyl sulfate in the biosynthetic hypobranchial glands. But during egg-laying, murexine was transferred to the capsule gland and then to the egg capsules, where chemical ripening resulted in Tyrian purple formation. Murexine was found to tranquilise the larvae and may relax the reproductive tract. This study shows that DIOS-MSI is a powerful tool that can provide new insights into marine chemo-ecology.

  • are the traditional medical uses of muricidae molluscs substantiated by their pharmacological properties and bioactive compounds
    Marine Drugs, 2015
    Co-Authors: Kirsten Benkendorff, David Rudd, Bijayalakshmi Devi Nongmaithem, Lei Liu, Fiona Young, Vicki Edwards, Catharine Avila, Catherine A Abbott
    Abstract:

    Marine molluscs from the family Muricidae hold great potential for development as a source of therapeutically useful compounds. Traditionally known for the production of the ancient dye Tyrian purple, these molluscs also form the basis of some rare traditional medicines that have been used for thousands of years. Whilst these traditional and alternative medicines have not been chemically analysed or tested for efficacy in controlled clinical trials, a significant amount of independent research has documented the biological activity of extracts and compounds from these snails. In particular, Muricidae produce a suite of brominated indoles with anti-inflammatory, anti-cancer and steroidogenic activity, as well as Choline Esters with muscle-relaxing and pain relieving properties. These compounds could explain some of the traditional uses in wound healing, stomach pain and menstrual problems. However, the principle source of bioactive compounds is from the hypobranchial gland, whilst the shell and operculum are the main source used in most traditional remedies. Thus further research is required to understand this discrepancy and to optimise a quality controlled natural medicine from Muricidae.

  • Solvent Separating Secondary Metabolites Directly from Biosynthetic Tissue for Surface-Assisted Laser Desorption Ionisation Mass Spectrometry
    MDPI AG, 2015
    Co-Authors: David Rudd, Kirsten Benkendorff, Nicolas H. Voelcker
    Abstract:

    Marine bioactive metabolites are often heterogeneously expressed in tissues both spatially and over time. Therefore, traditional solvent extraction methods benefit from an understanding of the in situ sites of biosynthesis and storage to deal with heterogeneity and maximize yield. Recently, surface-assisted mass spectrometry (MS) methods namely nanostructure-assisted laser desorption ionisation (NALDI) and desorption ionisation on porous silicon (DIOS) surfaces have been developed to enable the direct detection of low molecular weight metabolites. Since direct tissue NALDI-MS or DIOS-MS produce complex spectra due to the wide variety of other metabolites and fragments present in the low mass range, we report here the use of “on surface” solvent separation directly from mollusc tissue onto nanostructured surfaces for MS analysis, as a mechanism for simplifying data annotation and detecting possible artefacts from compound delocalization during the preparative steps. Water, ethanol, chloroform and hexane selectively extracted a range of Choline Esters, brominated indoles and lipids from Dicathais orbita hypobranchial tissue imprints. These compounds could be quantified on the nanostructured surfaces by comparison to standard curves generated from the pure compounds. Surface-assisted MS could have broad utility for detecting a broad range of secondary metabolites in complex marine tissue samples

Melani, Rafael Donadélli - One of the best experts on this subject based on the ideXlab platform.

  • Caracterização química e farmacológica de compostos não peptídicos presentes na peçonha da aranha caranguejeira Lasiodora sp.
    2012
    Co-Authors: Melani, Rafael Donadélli
    Abstract:

    A peçonha de aranhas é um conjunto de diferentes moléculas bioativas usadas para subjugar a presa e como mecanismo de defesa. Essas moléculas atuam de forma variada em diversos sistemas biológicos, porém pouco se sabe sobre as peçonhas de aranhas caranguejeiras do Brasil. Diante disso, o presente trabalho teve como objetivo realizar a caracterização química e farmacológica de alguns componentes bioativos não peptídicos presentes na peçonha de Lasiodora sp. A peçonha bruta de Lasiodora sp. apresenta efeito inotrópico e cronotrópico negativos em preparação de coração in situde rã e de contração e diminuição da resposta de acetilcolina (Ach) em relação ao controle, em preparação de músculo reto abdominal de rã. O efeito sobre o coração é atribuído ao acúmulo de Ach na peçonha na concentração de 8,75±0,45 µg/mg de peçonha bruta, quantificada analiticamente por LC-MS/MS. A presença de Ach também foi constatada na peçonha de outras aranhas e outros animais peçonhentos como escorpiões e lacraias. O efeito sobre o músculo ocorre nos receptores nicotínicos para Ach e está relacionado à presença de ésteres de colina com núcleos imidazólicos. Os compostos foram identificadosquimicamente através de diferentes revelações após cromatografia de camada delgada e por espectrometria de massa. Este estudo contribui para a compreensão da diversidade e complexidade de moléculas de baixa massa molecular não peptídicas presentes na peçonha da aranha Lasiodora sp., bem como preenche lacunas até então não esclarecidas. ______________________________________________________________________________ ABSTRACTThe spiders venoms are a diverse set of bioactive molecules used for predation and as a defense mechanism. Although these molecules act on many biological systems by different means, little is known about the tarantula spiders venoms from Brazil. Thus, the objective of this study was to characterize chemically andpharmacologically some of the non-peptide bioactive components present in the venom of Lasiodora sp. The crude venom of Lasiodora sp. presents inotropic and chronotropic negative effects in in situ frog heart preparation. In frog rectus abdominis preparation the crude venom led to contraction and decrease of the action of acetylCholine (Ach). The effect on the heart is attributed to Ach accumulation on the venom at a concentration of 8.75 ± 0.45 µg/mg of crude venom, analytically quantified by LC-MS/MS. The presence of Ach was also found in the venom of other spiders and other venomous animals such as scorpions and centipedes. The effect on the muscle occurs on nicotinic Ach receptors and is related to the presence Choline Esters with imidazole nuclei. The compounds were chemically identified by various spraying reagents after thin layer chromatography and by mass spectrometry. This study contributes to understand the molecular diversity and complexity of non-peptide compounds with low molecular weight present in the venom of the spider Lasiodora sp. and fills unexplained gaps in the study of tarantula venoms

  • Caracterização química e farmacológica de compostos não peptídicos presentes na peçonha da aranha caranguejeira Lasiodora sp.
    2012
    Co-Authors: Melani, Rafael Donadélli
    Abstract:

    Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Biologia Animal, 2012.A peçonha de aranhas é um conjunto de diferentes moléculas bioativas usadas para subjugar a presa e como mecanismo de defesa. Essas moléculas atuam de forma variada em diversos sistemas biológicos, porém pouco se sabe sobre as peçonhas de aranhas caranguejeiras do Brasil. Diante disso, o presente trabalho teve como objetivo realizar a caracterização química e farmacológica de alguns componentes bioativos não peptídicos presentes na peçonha de Lasiodora sp. A peçonha bruta de Lasiodora sp. apresenta efeito inotrópico e cronotrópico negativos em preparação de coração in situde rã e de contração e diminuição da resposta de acetilcolina (Ach) em relação ao controle, em preparação de músculo reto abdominal de rã. O efeito sobre o coração é atribuído ao acúmulo de Ach na peçonha na concentração de 8,75±0,45 µg/mg de peçonha bruta, quantificada analiticamente por LC-MS/MS. A presença de Ach também foi constatada na peçonha de outras aranhas e outros animais peçonhentos como escorpiões e lacraias. O efeito sobre o músculo ocorre nos receptores nicotínicos para Ach e está relacionado à presença de ésteres de colina com núcleos imidazólicos. Os compostos foram identificadosquimicamente através de diferentes revelações após cromatografia de camada delgada e por espectrometria de massa. Este estudo contribui para a compreensão da diversidade e complexidade de moléculas de baixa massa molecular não peptídicas presentes na peçonha da aranha Lasiodora sp., bem como preenche lacunas até então não esclarecidas. ______________________________________________________________________________ ABSTRACTThe spiders venoms are a diverse set of bioactive molecules used for predation and as a defense mechanism. Although these molecules act on many biological systems by different means, little is known about the tarantula spiders venoms from Brazil. Thus, the objective of this study was to characterize chemically andpharmacologically some of the non-peptide bioactive components present in the venom of Lasiodora sp. The crude venom of Lasiodora sp. presents inotropic and chronotropic negative effects in in situ frog heart preparation. In frog rectus abdominis preparation the crude venom led to contraction and decrease of the action of acetylCholine (Ach). The effect on the heart is attributed to Ach accumulation on the venom at a concentration of 8.75 ± 0.45 µg/mg of crude venom, analytically quantified by LC-MS/MS. The presence of Ach was also found in the venom of other spiders and other venomous animals such as scorpions and centipedes. The effect on the muscle occurs on nicotinic Ach receptors and is related to the presence Choline Esters with imidazole nuclei. The compounds were chemically identified by various spraying reagents after thin layer chromatography and by mass spectrometry. This study contributes to understand the molecular diversity and complexity of non-peptide compounds with low molecular weight present in the venom of the spider Lasiodora sp. and fills unexplained gaps in the study of tarantula venoms

Didier Fournier - One of the best experts on this subject based on the ideXlab platform.

  • Cholinesterase from the common prawn (Palaemon serratus) eyes: catalytic properties and sensitivity to organophosphate and carbamate compounds.
    Aquatic Toxicology, 2006
    Co-Authors: Manuela F Frasco, Didier Fournier, Félix Carvalho, Lúcia Guilhermino
    Abstract:

    The main purpose of this study was to describe the kinetic properties of the Cholinesterase (ChE) enzyme present in the eyes of the prawn Palaemon serratus, an abundant, ecological and commercially relevant species of European coastal environments. The obtained results suggest that the studied enzyme is a ChE and not a non-specific esterase, due to its apparent affinity for Choline Esters and the high sensitivity to eserine sulphate. This ChE displays a distinct preference for the substrate acetylthioCholine, showing a triphasic behaviour, with activation at low concentrations and inhibition by excess of substrate. Moreover, irreversible ChE inhibition by several organophosphate and carbamate compounds was characterized. All the irreversible inhibitions were homogeneous following a second-order rate reaction. The bimolecular rate constant (k(i)) values of ChE inhibition by the tested pesticides were also estimated and compared with available data from other invertebrate and vertebrate species. In conclusion, the results of the present study showed that prawn eyes possess only one ChE with typical properties of acetylCholinesterase, which is highly sensitive to the tested anti-Cholinesterase compounds.

  • is acetyl butyrylCholine specificity a marker for insecticide resistance mutations in insect acetylCholinesterase
    Pest Management Science, 2000
    Co-Authors: Francois Villatte, Philippe Ziliani, Sandino Estradamondaca, Philippe Menozzi, Didier Fournier
    Abstract:

    Substrate specificity has been widely studied in vertebrate Cholinesterases and it has been shown that two phenylalanines in the acyl pocket of acetylCholinesterase govern the acceptance of the acetyl/butyryl moiety of the Choline Esters. As an insecticide-resistance mutation has been evidenced in the acyl pocket of Drosophila melanogaster and Musca domestica acetylCholinesterase we investigated the possibility of linking changes in acetyl/butyrylthioCholine specificity with mutations in insect acetylCholinesterase. We thus analyzed the effect of 28 mutations in Drosophila enzyme on acetyl/butyrylthioCholine, N-methyl/N-propyl-carbamates and ethyl/methyl-paraoxon preference. It appeared that the highest changes on acetyl/butyrylthioCholine and N-propyl/N-methyl-carbamates preference were due to mutations in the acyl pocket. Nevertheless, other insecticide-resistance mutations, not located in the acyl pocket, also modified these substrate preferences. Moreover, the effect of mutations in the acyl pocket was hidden when some other insecticide-resistance mutations were combined in the enzyme. Consequently, acetyl/butyrylthioCholine preference alteration cannot be used as a marker to localize a mutation in the insect AChE. (Resume d'auteur)

Francois Villatte - One of the best experts on this subject based on the ideXlab platform.

  • is acetyl butyrylCholine specificity a marker for insecticide resistance mutations in insect acetylCholinesterase
    Pest Management Science, 2000
    Co-Authors: Francois Villatte, Philippe Ziliani, Sandino Estradamondaca, Philippe Menozzi, Didier Fournier
    Abstract:

    Substrate specificity has been widely studied in vertebrate Cholinesterases and it has been shown that two phenylalanines in the acyl pocket of acetylCholinesterase govern the acceptance of the acetyl/butyryl moiety of the Choline Esters. As an insecticide-resistance mutation has been evidenced in the acyl pocket of Drosophila melanogaster and Musca domestica acetylCholinesterase we investigated the possibility of linking changes in acetyl/butyrylthioCholine specificity with mutations in insect acetylCholinesterase. We thus analyzed the effect of 28 mutations in Drosophila enzyme on acetyl/butyrylthioCholine, N-methyl/N-propyl-carbamates and ethyl/methyl-paraoxon preference. It appeared that the highest changes on acetyl/butyrylthioCholine and N-propyl/N-methyl-carbamates preference were due to mutations in the acyl pocket. Nevertheless, other insecticide-resistance mutations, not located in the acyl pocket, also modified these substrate preferences. Moreover, the effect of mutations in the acyl pocket was hidden when some other insecticide-resistance mutations were combined in the enzyme. Consequently, acetyl/butyrylthioCholine preference alteration cannot be used as a marker to localize a mutation in the insect AChE. (Resume d'auteur)