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1.
Nat Chem Biol ; 17(5): 524-530, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33495646

RESUMO

Invasive species events related to globalization are increasing, resulting in parasitic outbreaks. Understanding of host defense mechanisms is needed to predict and mitigate against the consequences of parasite invasion. Using the honey bee Apis mellifera and the mite Varroa destructor, as a host-parasite model, we provide a comprehensive study of a mechanism of parasite detection that triggers a behavioral defense associated with social immunity. Six Varroa-parasitization-specific (VPS) compounds are identified that (1) trigger Varroa-sensitive hygiene (VSH, bees' key defense against Varroa sp.), (2) enable the selective recognition of a parasitized brood and (3) induce responses that mimic intrinsic VSH activity in bee colonies. We also show that individuals engaged in VSH exhibit a unique ability to discriminate VPS compounds from healthy brood signals. These findings enhance our understanding of a critical mechanism of host defense against parasites, and have the potential to apply the integration of pest management in the beekeeping sector.


Assuntos
Acetatos/isolamento & purificação , Abelhas/metabolismo , Comportamento Animal/fisiologia , Misturas Complexas/química , Cetonas/isolamento & purificação , Varroidae/química , Acetatos/química , Acetatos/farmacologia , Animais , Abelhas/citologia , Abelhas/efeitos dos fármacos , Abelhas/parasitologia , Comportamento Animal/efeitos dos fármacos , Bioensaio , Misturas Complexas/farmacologia , Feminino , Interações Hospedeiro-Parasita , Cetonas/química , Cetonas/farmacologia , Varroidae/patogenicidade
2.
Analyst ; 145(11): 4004-4011, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32347240

RESUMO

Methyl jasmonate (MeJA) and its free-acid form, jasmonic acid (JA), collectively referred to as jasmonates (JAs), are natural plant growth regulators that are widely present in higher plants. Simultaneous detection of JA and MeJA in plant samples is of significance and is a great challenging issue. In this study, coupling with two extraction methods, a sensitive monoclonal antibody (mAb) based enzyme-linked immunosorbent assay (ELISA) for simultaneous detection of JA and MeJA in plant samples was developed. The JA-bovine serum albumin (BSA) conjugate was used as an immunogen for the production of mAb. As the produced mAb exhibited higher recognition ability towards MeJA than towards JA, ELISA was established using MeJA as the standard. Under optimal experimental conditions, the IC50 and LOD values of ELISA for MeJA were 2.02 ng mL-1 and 0.20 ng mL-1, respectively. In the first extraction method, MeJA in plant samples was evaporated and only JA was extracted. In the second extraction method, both JA and MeJA were extracted. After methylation, JA in the extracts was converted into MeJA, and the whole MeJA in the extracts was measured by ELISA. Plant samples including the leaves of Salvia splendens, the flowers of Salvia splendens and the fruit of grapes were collected. JA and MeJA in these samples were detected by the proposed ELISA. It was found that the concentrations of JA in these three plant samples were about 3-5 times higher than those of MeJA in those samples. ELISA was also confirmed by HPLC. There was a good correlation between ELISA and HPLC.


Assuntos
Acetatos/análise , Anticorpos Monoclonais/imunologia , Ciclopentanos/análise , Oxilipinas/análise , Reguladores de Crescimento de Plantas/análise , Acetatos/imunologia , Acetatos/isolamento & purificação , Animais , Ciclopentanos/imunologia , Ciclopentanos/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Feminino , Flores/química , Frutas/química , Camundongos Endogâmicos BALB C , Oxilipinas/imunologia , Oxilipinas/isolamento & purificação , Reguladores de Crescimento de Plantas/imunologia , Reguladores de Crescimento de Plantas/isolamento & purificação , Folhas de Planta/química , Salvia/química , Extração em Fase Sólida , Vitis/química
3.
Molecules ; 25(4)2020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32079080

RESUMO

In the last decade, there has been growing interest in the food industry in replacing synthetic chemicals with natural products with bioactive properties. This study's aims were to determine the chemical composition and the antioxidant properties of the essential oil of Pastianica sylvestris. The essential oil was isolated with a yield of 0.41% (w/v) by steam distillation from the dried seeds and subsequently analysed by GC-MS. Octyl acetate (78.49%) and octyl hexanoate (6.68%) were the main components. The essential oil exhibited an excellent activity for the inhibition of primary and secondary oxidation products for cold-pressed sunflower oil comparable with butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), which were evaluated using peroxide and thiobarbituric acid values. The antioxidant activity of the essential oil was additionally validated using DPPH radical scavenging (0.0016 ± 0.0885 mg/mL), and ß-carotene-linoleic acid bleaching assays. Also, the amounts of total phenol components (0.0053 ± 0.0023 mg GAE/g) were determined.


Assuntos
Acetatos/química , Antioxidantes/química , Óleos Voláteis/química , Pastinaca/química , Sementes/química , Acetatos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bioensaio , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Hidroxianisol Butilado/química , Hidroxianisol Butilado/isolamento & purificação , Hidroxitolueno Butilado/química , Cromatografia Gasosa-Espectrometria de Massas , Ácido Linoleico/química , Óleos Voláteis/isolamento & purificação , Fenóis/química , Picratos/antagonistas & inibidores , Picratos/química , Extratos Vegetais/química , Óleo de Girassol/química , Tiobarbitúricos/química , beta Caroteno/química
4.
Mol Biol Rep ; 47(3): 1871-1881, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006197

RESUMO

A recent spike in demand for chemical preservative free food has derived the scientific community to develop natural ways of food preservation. Therefore, bio-preservation could be considered as the great alternative over chemical ones owing to its potential to increase shelf-life and nutritional values of foodstuffs. In the present study, lactic acid producing bacterial species were isolated from rice rinsed water and identified by 16S rRNA gene sequencing as Lactobacillus plantarum BCH-1 (KX388380) and Lactobacillus coryniformis BCH-4 (KX388387). Antifungal metabolites from both Lactobacillus species were extracted by polarity-based solvents in which ethyl acetate showed remarkable antifungal activity against Aspergillus flavus and Aspergillus fumigatus by disc diffusion assay. Different organic acids and fatty acids have been identified by reversed-phase high-performance liquid chromatography (RP-HPLC) and gas chromatography-mass spectrometry (GC-MS) analysis, respectively. Lactic acid and citric acid were the major organic acids found in ethyl acetate fractions of L. plantarum and L. coryniformis, respectively. Similarly, 9,12-otadecadienoic acid (Z,Z)-methyl ester and hexadecanoic acid, methyl ester were the major fatty acids found in n-hexane fractions of L. plantarum and L. coryniformis respectively. Moreover, the isolation of novel antifungal metabolites from locally isolated Lactobacillus species was focused and it was revealed that organic acids are important contributors towards antifungal potential. A novel fatty acid (i.e. 12-hydroxydodecanoic acid) has also been explored and found as potential metabolite against filamentous fungi. Conclusively, various metabolites isolated from non-dairy source showed antifungal activity especially against Aspergillus species. Hence, these metabolites have been considered as a good choice for bio-preservation.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Lactobacillus/classificação , Metabolômica/métodos , Oryza/microbiologia , Acetatos/isolamento & purificação , Antifúngicos/isolamento & purificação , Aspergillus/crescimento & desenvolvimento , Cromatografia de Fase Reversa , DNA Fúngico/genética , DNA Ribossômico/genética , Conservação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Lactobacillus/química , Lactobacillus/genética , Lactobacillus/isolamento & purificação , Lactobacillus plantarum/química , Lactobacillus plantarum/genética , Lactobacillus plantarum/isolamento & purificação , Ácidos Láuricos/isolamento & purificação , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
5.
Methods Mol Biol ; 2085: 109-115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31734920

RESUMO

Symbiotic association of plants with arbuscular mycorrhizal (AM) fungi brings about changes in levels of the phytohormone jasmonate (JA) in root and shoot tissues of a plant. The enhanced JA levels not only play a role in controlling the extent of AM colonization but are also involved in the expression of mycorrhizal-induced resistance (MIR) against pathogens. We describe a method used to study the levels of a volatile jasmonate derivative, methyl jasmonate (MeJA), in tomato plants colonized by AM fungi and in response to subsequent attack by the foliar pathogen Alternaria alternata.


Assuntos
Ciclopentanos/metabolismo , Resistência à Doença , Fungos , Micorrizas , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Acetatos/química , Acetatos/isolamento & purificação , Acetatos/metabolismo , Cromatografia Gasosa , Ciclopentanos/química , Ciclopentanos/isolamento & purificação , Interações Hospedeiro-Patógeno , Oxilipinas/química , Oxilipinas/isolamento & purificação , Simbiose
6.
An Acad Bras Cienc ; 91(3): e20180462, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31553365

RESUMO

This study aimed to evaluate the in vitro antiproliferative and inhibition of oxidative DNA-damage activities of n-butanol (n-BuOH) extract of Centaurea sphaerocephala. The in vitro antioxidant activity of the ethyl acetate (EtOAc) and the n-BuOH extracts of this plant were also assayed. To investigate the antioxidant potential, extracts were tested for their capacity to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH·) and to inhibit lipid peroxidation using the TBARs method. The contents of total phenolics and flavonoids were measured. Additionally, antiproliferative activity and DNA-damage inhibition of the n-BuOH extract was determined using XCELLigence RTCA instrument and photolyzing 46966 plasmid, respectively. The results exhibited that the scavenging abilities of the EtOAc extract were better than the n-BuOH extract with an IC50= 11.59 µg/mL and 16.67 µg/mL for both extracts, respectively. The phenolic and flavonoid contents were found higher in the n-BuOH and EtOAc extracts. Furthermore, our results showed that n-BuOH extract exhibited a remarkable inhibition of lipid peroxidation with an IC50 of 340.94±7.49 µg/mL and had an antiproliferative effect against Hela cells. Extracts of C. sphaerocephala showed antioxidant activity on scavenging DPPH·. In addition, the n-BuOH extract inhibited the lipid peroxidation and exhibited an antiproliferative effect against HeLa cells line (human cervix carcinoma).


Assuntos
1-Butanol/farmacologia , Acetatos/farmacologia , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Centaurea/química , Dano ao DNA/efeitos dos fármacos , Extratos Vegetais/farmacologia , 1-Butanol/isolamento & purificação , Acetatos/isolamento & purificação , Antioxidantes/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Espectrometria de Massas
7.
Biomolecules ; 9(9)2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31492031

RESUMO

The short postharvest life of cassava is mainly due to its rapid postharvest physiological deterioration (PPD) and cell oxidative damage, however, how to effectively control this remains elusive. In this study, South China 5 cassava slices were sprayed with water and methyl jasmonate (MeJA) to study the effects of MeJA on reactive oxygen species, antioxidant enzymes, quality, endogenous hormone levels, and melatonin biosynthesis genes. We found that exogenous MeJA could delay the deterioration rate for at least 36 h and alleviate cell oxidative damage through activation of superoxide dismutase, catalase, and peroxidase. Moreover, MeJA increased the concentrations of melatonin and gibberellin during PPD, which had a significant effect on regulating PPD. Notably, exogenous MeJA had a significant effect on maintaining cassava quality, as evidenced by increased ascorbic acid content and carotenoid content. Taken together, MeJA treatment is an effective and promising way to maintain a long postharvest life, alleviate cell oxidative damage, and regulate storage quality in cassava.


Assuntos
Acetatos/farmacologia , Ciclopentanos/farmacologia , Manihot/efeitos dos fármacos , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Acetatos/química , Acetatos/isolamento & purificação , Ciclopentanos/química , Ciclopentanos/isolamento & purificação , Manihot/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxilipinas/química , Oxilipinas/isolamento & purificação , Fenômenos Fisiológicos/efeitos dos fármacos , Reguladores de Crescimento de Plantas/química , Reguladores de Crescimento de Plantas/isolamento & purificação
8.
Talanta ; 205: 120107, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450415

RESUMO

A comprehensive structural characterization of the complex family of isomeric forms related to Oleuropein aglycone (OA) detected in virgin olive oil (VOO) was performed by reverse phase liquid chromatography with electrospray ionization and Fourier-transform mass spectrometry (RPLC-ESI-FTMS), integrated by enzymatic/chemical reactions performed on Oleuropein, the natural precursor of OA. First, some of the OA-related isomers typically observed in VOO extracts were generated upon enzymatic hydrolysis of the glycosidic linkage of Oleuropein. This step mimicked the process occurring during olive drupes crushing in the first stage of oil production. The incubation of the enzymatic reaction mixture at a more acidic pH was subsequently performed, to simulate the conditions of olive paste malaxation during oil production. As a result, further isomeric forms were generated and the complex chromatographic profile typically observed for OA in olive oil extracts, including at least 13 different peaks/bands/groups of peaks, was carefully reproduced. Each of those chromatographic features could be subsequently assigned to specific types of OA-related isomers, belonging to one of four structurally different classes. Specifically, diastereoisomers/geometrical isomers corresponding to two different types of open-structure forms and to as many types of closed-structure, di-hydropyranic forms of OA, characterized by the presence of one or two carbonyl groups, according to the case, were evidenced. In addition, the presence of stable enolic/dienolic tautomers, providing an indirect structural confirmation for some OA isomers, was ascertained through RPLC-ESI-FTMS analyses performed under H/D exchange conditions, i.e. in the presence of deuterated water as one of the mobile phase solvents.


Assuntos
Acetatos/análise , Monoterpenos Ciclopentânicos/análise , Azeite de Oliva/análise , Piranos/análise , Acetatos/química , Acetatos/isolamento & purificação , Cromatografia de Fase Reversa/métodos , Monoterpenos Ciclopentânicos/química , Monoterpenos Ciclopentânicos/isolamento & purificação , Deutério , Análise de Fourier , Hidrólise , Glucosídeos Iridoides , Iridoides/química , Isomerismo , Extração Líquido-Líquido , Olea/química , Piranos/química , Piranos/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , beta-Glucosidase/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-31323559

RESUMO

The present study was conducted to check the comparative qualities of essential oils prepared by hydrodistillation (HD) and supercritical fluid techniques. It constitutes the first attempt to investigate the chemical composition of Daucus carota subsp. maritimus extracts using supercritical fluid technology (SFE) as an environmentally clean innovative method of extraction. The effect of pressure on the nature of extractable substances from wild carrot has been performed at a constant temperature of 50 °C and two different pressures (100 and 300 bar). The experimental results showed that pressure had a significant enhancing effect on the fluid transport properties and therefore on yield values. The extraction yield increases from 1.167 to 2.986% while increasing pressure. The chemical compositions of the essential oils prepared by HD and SFE were analyzed on the basis of gas chromatography-mass spectroscopy (GC-MS). Thus, we noticed that all analyzed samples were enriched in geranyl acetate and ß­bisabolene, and that the quantities of different identified substances were extremely sensitive to the extraction method and to the pressure variation in case of SFE.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Daucus carota/química , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Acetatos/análise , Acetatos/isolamento & purificação , Monoterpenos Acíclicos/análise , Monoterpenos Acíclicos/isolamento & purificação , Sesquiterpenos Monocíclicos/análise , Sesquiterpenos Monocíclicos/isolamento & purificação , Óleos Voláteis/análise , Óleos de Plantas/análise , Pressão
10.
Environ Sci Pollut Res Int ; 26(13): 12851-12858, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30891698

RESUMO

Volatile organic compounds (VOCs) are of public concern due to their adverse health effects. Botanical air filtration is a promising technology for reducing indoor air contaminants, but the underlying mechanisms are not fully understood. This study assessed active botanical biofilters for their single-pass removal efficiency (SPRE) for benzene, ethyl acetate and ambient total volatile organic compounds (TVOCs), at concentrations of in situ relevance. Biofilters containing four plant species (Chlorophytum orchidastrum, Nematanthus glabra, Nephrolepis cordifolia 'duffii' and Schefflera arboricola) were compared to discern whether plant selection influenced VOC SPRE. Amongst all tested plant species, benzene SPREs were between 45.54 and 59.50%, with N. glabra the most efficient. The botanical biofilters removed 32.36-91.19% of ethyl acetate, with C. orchidastrum and S. arboricola recording significantly higher ethyl acetate SPREs than N. glabra and N. cordifolia. These findings thus indicate that plant type influences botanical biofilter VOC removal. It is proposed that ethyl acetate SPREs were dependent on hydrophilic adsorbent sites, with increasing root surface area, root diameter and root mass all associated with increasing ethyl acetate SPRE. The high benzene SPRE of N. glabra is likely due to the high wax content in its leaf cuticles. The SPREs for the relatively low levels of ambient TVOCs were consistent amongst plant species, providing no evidence to suggest that in situ TVOC removal is influenced by plant choice. Nonetheless, as inter-species differences do exist for some VOCs, botanical biofilters using a mixture of plants is proposed.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Plantas , Compostos Orgânicos Voláteis/isolamento & purificação , Acetatos/isolamento & purificação , Benzeno/isolamento & purificação , Biodegradação Ambiental , Folhas de Planta/química , Especificidade da Espécie
11.
J Org Chem ; 84(8): 4763-4779, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30557503

RESUMO

A robust process to manufacture AMG 232 was developed to deliver drug substance of high purity. Highlights of the commercial process development efforts include the following: (i) use of a novel bench-stable Vilsmeier reagent, methoxymethylene- N, N-dimethyliminium methyl sulfate, for selective in situ activation of a primary alcohol intermediate; (ii) use of a new crystalline and stable isopropyl calcium sulfinate reagent ensuring robust preparation of a sulfone intermediate; (iii) development of a safe ozonolysis process conducted in an aqueous solvent mixture in either batch or continuous manufacturing mode; and (iv) control of the drug substance purity by crystallization of a salt rejecting impurities effectively. The new process was demonstrated to afford the drug substance (99.9 LC area %) in 49.8% overall yield from starting material DLAC (1).


Assuntos
Acetatos/síntese química , Ozônio/química , Piperidonas/síntese química , Acetatos/química , Acetatos/isolamento & purificação , Estrutura Molecular , Piperidonas/química , Piperidonas/isolamento & purificação
12.
Daru ; 26(2): 105-116, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30242672

RESUMO

PURPOSE: Cancer disease is the second cause of death in the world. Now a days, high percentage of drugs, which are involved in treatment of cancers, have natural origin. Introduction of microalgae strains as anti-cancer drugs origin is a valuable approach for cancer therapy. METHODS: In the present study we describe the isolation, characterization, and anti-proliferative activity of a new microalga strain (Picochlorum sp. RCC486) from Iran. The cytotoxic activity of four different algal extracts including methanol, ethyl acetate, chloroform, and hexane were evaluated against MDA-MB-231, MCF-7, Hep-G2, and A-549 cell liens. Cell viability was determined using MTT assay in both monolayer and spheroids 3D cultures. The apoptosis was confirmed by different methods such as AO/EB and Annexin V-FITC/PI double staining, caspase-3 colorimetric assay, ROS and MMP assay. RESULTS: The results of MTT assay and fluorescent double staining confirmed that methanol and ethyl acetate extracts showed the best cytotoxic activity against the cancer cell lines. The production of ROS, caspase-3 activity and depolarized MMP were quite significant in MDA-MB-231 cell line treated with methanol and ethyl acetate extracts. CONCLUSION: In this research we revealed that cytotoxicity and apoptotic effects of the methanol and ethyl acetate extracts in human cancer cells make them good candidates for further pharmacological studies to discover effective drugs for cancer therapy. Graphical abstract The present study describes the isolation, characterization, and anti-proliferative activity of different extracts of a new microalga strain (Picochlorum sp. RCC486) from Iran. The antiproliferative and apoptosis inducing activity of ethyl acetate and methanol extracts with high content of phenol and carotenoid make them as good candidates for further pharmacological studies to discover effective drugs for cancer therapy.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Fatores Biológicos/isolamento & purificação , Fatores Biológicos/farmacologia , Técnicas de Cultura de Células/métodos , Microalgas/química , Células A549 , Acetatos/isolamento & purificação , Acetatos/farmacologia , Antineoplásicos/química , Fatores Biológicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Clorofórmio/isolamento & purificação , Clorofórmio/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Hexanos/isolamento & purificação , Hexanos/farmacologia , Humanos , Células MCF-7 , Metanol/isolamento & purificação , Metanol/farmacologia , Espécies Reativas de Oxigênio , Esferoides Celulares/citologia , Esferoides Celulares/efeitos dos fármacos , Células Tumorais Cultivadas
13.
J Sep Sci ; 41(22): 4149-4158, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30194810

RESUMO

A zirconium(IV)-based metal organic framework, composed of 4,4'-biphenyldicarboxylic acid ligands and Zr6 O4 (OH)4 clusters, was successfully fabricated. Characterizations were performed on fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller, and thermogravimetric analysis, which confirmed that it possessed large specific surface area, high pore volume, and strong acid resistant stability. Furthermore, the prepared material containing biphenyl skeleton and a large number of Zr-O bonds, can grasp acid herbicides especially phenoxyacetic acid herbicides with aromatic structures through π-π interaction, hydrophobic interaction and Zr-O-H+ bonds. Based on these advantages, a method was developed for the determination of four phenoxyacetic acid herbicides from vegetable samples. Under the optimal conditions, wide linearities from 0.3 to 250 µg/L and low limits of detection from 0.1 to 0.5 µg/L were obtained. The intra- and interday relative standard deviations were 1.56-3.92 and 5.01-7.65%, respectively. The proposed method was applied to analyze phenoxyacetic acid herbicides residues in the tomato, cucumber, and white gourd samples. The satisfactory recoveries (86.12-103.44%) for the spiked samples in vegetable samples were achieved which demonstrated the method was an efficient pretreatment procedure and has a potential application for the trace determination of phenoxyacetic acids from a complex matrix.


Assuntos
Acetatos/isolamento & purificação , Herbicidas/isolamento & purificação , Estruturas Metalorgânicas/química , Compostos Organometálicos/química , Extração em Fase Sólida , Verduras/química , Zircônio/química , Acetatos/química , Adsorção , Herbicidas/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
14.
Talanta ; 188: 107-110, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30029352

RESUMO

The arsenic speciation was determined in macrofungi of the Ramaria genus with HPLC coupled to inductively coupled plasma mass spectrometry. Besides arsenic species that are already known for macrofungi, like arsenobetaine or arsenocholine, two compounds that were only known from marine samples so far (trimethylarsoniopropanate and dimethylarsinoylacetate) were found for the first time in a terrestrial sample. An unknown arsenical was isolated and identified as homoarsenocholine. This could be a key intermediate for further elucidation of the biotransformation mechanisms of arsenic.


Assuntos
Arsenicais/isolamento & purificação , Acetatos/química , Acetatos/isolamento & purificação , Arsenicais/química , Basidiomycota/química
15.
J Ethnopharmacol ; 224: 421-428, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29933012

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Semen Torreyae, the seeds of Torreya grandis Fortune ex Lindley (Cephalotaxaceae) is a well-known traditional Chinese medicinal plant recorded in the Chinese Pharmacopeia (2010 version). It is widely used for treating intestinal parasites in China, owing to its desirable efficacy and safety. However, the anthelmintic compounds in Semen Torreyae have not yet been identified. AIM OF THE STUDY: This study aims to identify the compounds active against helminths from Semen Torreyae. In addition, we tested whether C. elegans strains resistant to currently-used anthelmintic drugs showed cross-resistance to these compounds. METHODS: A bioassay-guided isolation of anthelmintic compounds from Semen Torreyae was performed using a Caenorhabditis elegans (C. elegans) testing model. The structures of active compounds were elucidated by a combination of GC-MS, high resolution MS, and NMR. The median-effect method was employed to generate a combination index (CI) to evaluate the synergistic effect of the anthelmintic compounds. A panel of C. elegans mutant strains resistant against the major anthelmintic drug classes was used to study the cross-resistance to currently-used anthelmintic drugs. A panel of transient receptor potential (TRP) channel mutant strains was also tested to explore the possible mechanisms of action of the anthelmintic compounds. RESULTS: The bioassay-guided isolation led to two active compounds, i.e. galangal acetate (IC50: 58.5 ±â€¯8.9 µM) and miogadial (IC50: 25.1 ±â€¯5.4 µM). The combination of galangal acetate and miogadial resulted in a synergistic effect at IC50, IC70, and IC90 levels (CIs < 1). Galangal acetate and miogadial demonstrated similar activity against drug-resistant C. elegans strains compared to the wild-type strain. In addition, none of the TRP mutants was significantly resistant to galangal acetate or miogadial compared to wild type worms. CONCLUSIONS: We identified the bioactive compounds from Semen Torreyae responsible for its anthelmintic activity: galangal acetate and miogadial. The two anthelmintic compounds demonstrated a synergistic effect against C. elegans. Galangal acetate and miogadial are unlikely to act on the targets of currently-used anthelmintics (ivermectin, levamisole, benomyl and aldicarb), and an action on TRP channels appears to be ruled out as well. In summary, galangal acetate and miogadial are promising anthelmintic hits worth further investigation.


Assuntos
Acetatos/farmacologia , Anti-Helmínticos/farmacologia , Derivados de Benzeno/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Diterpenos/farmacologia , Extratos Vegetais/farmacologia , Sementes/química , Taxaceae/química , Acetatos/isolamento & purificação , Animais , Anti-Helmínticos/isolamento & purificação , Derivados de Benzeno/análise , Derivados de Benzeno/isolamento & purificação , Bioensaio , Caenorhabditis elegans/genética , Diterpenos/isolamento & purificação , Sinergismo Farmacológico , Mutação , Extratos Vegetais/isolamento & purificação , Canais de Potencial de Receptor Transitório/genética
16.
J Antibiot (Tokyo) ; 71(7): 667-671, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29666478

RESUMO

Two new spliceostatin derivatives, designed as spliceostatin H (1) and spliceostatin I (2), and one known compound FR901464 (3), were isolated from the strain Pseudomonas sp. HS-NF-1408. Their structures were determined by the comprehensive spectroscopic data, including 1D, 2D NMR, MS spectral analysis and comparison with data from the literature. Compound 1 exhibited potent cytotoxicity activity against A549 and HepG2 with IC50 values of 3.57 and 16.72 µg/ml, respectively.


Assuntos
Acetatos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Imino Piranoses/farmacologia , Pseudomonas/química , Piranos/farmacologia , Acetatos/isolamento & purificação , Antibióticos Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Fermentação , Humanos , Imino Piranoses/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Piranos/isolamento & purificação
17.
Food Chem ; 257: 350-360, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622221

RESUMO

Mixed fermentations with Starmerella bacillaris and Saccharomyces cerevisiae affect the chemical composition of wines, by modulating various metabolites of oenological interest. The current study was carried out to elucidate the effect of sequential inoculation of the above mentioned species on the production of white wines, especially on the chemical and aromatic characteristics of Chardonnay, Muscat, Riesling and Sauvignon blanc wines. Titratable acidity and glycerol content exhibited evident differences among the wines after fermentation. For volatile compounds, mixed fermentations led to a reduction of the total esters, including ethyl acetate, which is a compound responsible for wine deterioration. However, Sauvignon blanc wines fermented by mixed cultures contained significantly higher levels of esters and thiols, both associated with positive sensory attributes. These findings suggest that sequential inoculations possess great potential in affecting and modulating the chemical and aromatic profile of white wines, especially those produced from Sauvignon blanc grapes.


Assuntos
Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismo , Compostos Orgânicos Voláteis/análise , Vinho/análise , Acetatos/análise , Acetatos/isolamento & purificação , Reatores Biológicos , Cromatografia Gasosa , Ácidos Graxos/análise , Compostos de Sulfidrila/análise , Terpenos/análise , Compostos Orgânicos Voláteis/isolamento & purificação
18.
Talanta ; 180: 176-181, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29332797

RESUMO

Preconcentration is an effective way to improve analytical sensitivity. Many types of methods are used for enrichment of ionic solute analytes. However, current methods are batchwise and include procedures such as trapping and elution. In this manuscript, we propose in-line electrodialytic enrichment of ionic solutes. The method can enrich ionic solutes within seconds by quantitative transfer of analytes from the sample solution to the acceptor solution under an electric field. Because of quantitative ion transfer, the enrichment factor (the ratio of the concentration in the sample and to that in the obtained acceptor solution) only depends on the flow rate ratio of the sample solution to the acceptor solution. The ratios of the concentrations and flow rates are equal for ratios up to 70, 20, and 70 for the tested ionic solutes of inorganic cations, inorganic anions, and heavy metal ions, respectively. The sensitivity of ionic solute determinations is also improved based on the enrichment factor. The method can also simultaneously achieve matrix isolation and enrichment. The method was successively applied to determine the concentrations of trace amounts of chloroacetic acids in tap water. The regulated concentration levels cannot be determined by conventional high-performance liquid chromatography with ultraviolet detection (HPLC-UV) without enrichment. However, enrichment with the present method is effective for determination of tap water quality by improving the limits of detection of HPLC-UV. The standard addition test with real tap water samples shows good recoveries (94.9-109.6%).


Assuntos
Acetatos/análise , Técnicas Eletroquímicas/métodos , Íons/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Acetatos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Água Potável/análise , Íons/análise , Metais Pesados/análise , Metais Pesados/isolamento & purificação , Poluentes Químicos da Água/análise
19.
Nat Prod Res ; 32(22): 2646-2651, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28920481

RESUMO

Two new lignans, namely 7-O-podophyllotoxinyl butyrate (1) and dihydroclusin 9-acetate (2), were isolated from the dichloromethane fraction of a methanol extract of Bursera microphylla (Burseraceae), along with eight known lignans (3-10). Their structures were determined by means of comprehensive spectroscopic analysis. Lignans 2-6 were tested for their anti-proliferative activity on the cancer cell lines LS180, A549 and HeLa, and on a non-cancer cell line, ARPE-19. Only compounds 4 and 5 showed an interesting activity on HeLa cells.


Assuntos
Acetatos/farmacologia , Bursera/química , Butiratos/farmacologia , Lignanas/farmacologia , Resinas Vegetais/química , Acetatos/isolamento & purificação , Butiratos/isolamento & purificação , Linhagem Celular Tumoral , Células HeLa , Humanos , Lignanas/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química
20.
Nat Prod Res ; 32(16): 1967-1970, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28768425

RESUMO

Vibrio spp. are pathogens of many bacterial diseases which have caused great economic losses in marine aquaculture. The strategy of alternative medical treatment that is utilised by herbalists has expanded in the past decade. The aim of our study is to discover the antibacterial molecules against Vibrio spp. Bacterial growth inhibition, membrane permeabilisation assessment and DNA interaction assays, as well as agarose gel electrophoresis, were employed to elucidate the antibacterial activity of hydroxytyrosol acetate. Results showed that hydroxytyrosol acetate had antibacterial activity against Vibrio spp. and it played the role via increasing bacterial membrane permeabilisation. The DNA interaction assay and agarose gel electrophoresis revealed that hydroxytyrosol acetate interacted with DNA. Hydroxytyrosol acetate enhanced the fluorescent intensity of DNA binding molecules and mediated supercoiled DNA relaxation. The present study provides more evidence that hydroxytyrosol acetate is a novel antibacterial candidate against Vibrio spp.


Assuntos
Acetatos/isolamento & purificação , Antibacterianos/isolamento & purificação , Catecóis/isolamento & purificação , Olea/química , Extratos Vegetais/farmacologia , Acetatos/química , Acetatos/metabolismo , Acetatos/farmacologia , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Catecóis/metabolismo , Catecóis/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , DNA Bacteriano/metabolismo , Álcool Feniletílico/análogos & derivados , Extratos Vegetais/química , Vibrio/efeitos dos fármacos , Vibrio/ultraestrutura
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