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1.
Prog Chem Org Nat Prod ; 109: 1-384, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31637529

RESUMO

Isolation, structure determination, synthesis, and biochemistry of the low-molecular-weight compounds of the secretion of exocrine glands of termites are described, with an emphasis on pheromones and defensive compounds.


Assuntos
Glândulas Exócrinas/química , Isópteros/química , Feromônios/química , Animais , Metabolismo Secundário
2.
Microbiol Res ; 229: 126329, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31518853

RESUMO

The genus Serratia is a predominantly unexplored source of antimicrobial secondary metabolites. The aim of the current study was thus to isolate and evaluate the antimicrobial properties of biosurfactants produced by Serratia species. Forty-nine (n = 34 pigmented; n = 15 non-pigmented) biosurfactant producing Serratia strains were isolated from environmental sources and selected isolates (n = 11 pigmented; n = 11 non-pigmented) were identified as Serratia marcescens using molecular typing. The swrW gene (serrawettin W1 synthetase) was detected in all the screened pigmented strains and one non-pigmented strain and primers were designed for the detection of the swrA gene (non-ribosomal serrawettin W2 synthetase), which was detected in nine non-pigmented strains. Crude extracts obtained from S. marcescens P1, NP1 and NP2 were chemically characterised using ultra-performance liquid chromatography coupled to electrospray ionisation mass spectrometry (UPLC-ESI-MS), which revealed that P1 produced serrawettin W1 homologues and prodigiosin, while NP1 produced serrawettin W1 homologues and glucosamine derivative A. In contrast, serrawettin W2 analogues were predominantly identified in the crude extract obtained from S. marcescens NP2. Both P1 and NP1 crude extracts displayed broad-spectrum antimicrobial activity against clinical, food and environmental pathogens, such as multidrug-resistant Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and Cryptococcus neoformans. In contrast, the NP2 crude extract displayed antibacterial activity against a limited range of pathogenic and opportunistic pathogens. The serrawettin W1 homologues, in combination with prodigiosin and glucosamine derivatives, produced by pigmented and non-pigmented S. marcescens strains, could thus potentially be employed as broad-spectrum therapeutic agents against multidrug-resistant bacterial and fungal pathogens.


Assuntos
Antibacterianos/farmacologia , Depsipeptídeos/farmacologia , Lipoproteínas/farmacologia , Peptídeos Cíclicos/farmacologia , Prodigiosina/farmacologia , Serratia marcescens/química , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Depsipeptídeos/química , Depsipeptídeos/metabolismo , Lipoproteínas/química , Lipoproteínas/metabolismo , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Prodigiosina/química , Prodigiosina/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Metabolismo Secundário , Serratia marcescens/metabolismo , Tensoativos/química , Tensoativos/metabolismo , Tensoativos/farmacologia
3.
Bioengineered ; 10(1): 316-334, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31347943

RESUMO

In the development of medicinally important Orchidaceae, the extent of fungal endophytes specificity is not presently very clear. Limited study has been available on natural products formed and its role on plant growth, defence mechanism by endophytes, and to characterize the chief treasure of bioactive molecules. Therefore, this review article presents an evaluation of the endophytes associated with Orchidaceae for physiology, metabolism, and genomics which have prominently contributed to the resurgence of novel metabolite research increasing our considerate of multifaceted mechanisms regulatory appearance of biosynthetic gene groups encoding diverse metabolites. Additionally, we presented the comprehensive recent development of bio-strategies for the cultivation of endophytes from Orchidaceae and integration of bioengineered 'Genomics with metabolism' approaches with emphases collective omics as powerful approach to discover novel metabolite compounds. The Orchidaceae-fungal endophytes' biodynamics for sustainable development of bioproducts and its applications are supported in large-scale biosynthesis of industrially and pharmaceutical important biomolecules.


Assuntos
Produtos Biológicos/química , Endófitos/metabolismo , Fungos/metabolismo , Orchidaceae/microbiologia , Simbiose/fisiologia , Produtos Biológicos/isolamento & purificação , Endófitos/classificação , Endófitos/genética , Fungos/classificação , Fungos/genética , Redes e Vias Metabólicas/fisiologia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia , Metabolismo Secundário/fisiologia
4.
J Agric Food Chem ; 67(31): 8500-8509, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298534

RESUMO

To map qualitative and quantitative metabolome alterations when Penicillium roqueforti is grown in an environment where l-tyrosine levels are perturbed, the recently established differential off-line LC-NMR (DOLC-NMR) approach was successfully applied in connection with an absolute metabolite quantitation using a quantitative 1H NMR protocol following the ERETIC 2 (Electronic REference To access In vivo Concentrations) methodology. Among the 23 influenced metabolites, amino acid degradation products like 2-(4-hydroxyphenyl)acetic acid and 2-(3,4-dihydroxyphenyl)acetic acid underwent a tremendous upregulation in the amino acid perturbed approach. Moreover, the output of secondary metabolites like andrastin A, eremofortin B, and the tetrapeptide d-Phe-l-Val-d-Val-l-Tyr was affected in the case of the presence or absence of the added aromatic amino acid. Furthermore, the isolated secondary metabolites of P. roqueforti have been quantified for the first time in five divergent Penicillium isolates by means of a validated LC-ECHO-MS/MS method. This technique is used to compensate the effect of co-extracted matrix compounds during the analysis and to utilize quasi-internal standards to quantify all metabolites of interest accurately. This screening outlined the great variety between the different fungi of the same species. The metabolite spectra of wild-type fungi included more toxic intermediates compared to a selected fungi used as a starter culture for blue-mold cheese production. In addition, these secondary metabolites were quantified in commercially available white- and blue-mold cheese samples. The main differences between the analyte profiles of white and blue cheeses were linked to the impact of the used starter culture. Specific metabolites detected from P. roqueforti like andrastin A and B or roquefortine C could not be detected in white cheese. Among the blue cheese samples, different metabolite pattern could be observed regarding various P. roqueforti starter cultures.


Assuntos
Queijo/microbiologia , Metaboloma , Penicillium/metabolismo , Metabolismo Secundário , Tirosina/metabolismo , Aminoácidos Aromáticos/análise , Aminoácidos Aromáticos/metabolismo , Androstadienos/análise , Androstadienos/metabolismo , Queijo/análise , Penicillium/química , Penicillium/crescimento & desenvolvimento , Peptídeos/análise , Peptídeos/metabolismo , Sesquiterpenos/análise , Sesquiterpenos/metabolismo , Espectrometria de Massas em Tandem
5.
Fitoterapia ; 137: 104278, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31351910

RESUMO

Five new cytochalasans (1-5) were isolated from the rice fermentation of fungus Xylaria longipes, along with seven known compounds cytochalasin P (6), cytochalasin D (7), zygosporin D (8), 7-O-acetylcytochalasin D (9), cytochalasin C (10), 6,7-dihydro-7-oxo-cytochalasin C (11), and 6,7-dihydro-7-oxo-deacetylcytochalasin C (12). Their structures and absolute configurations were determined by extensive experimental spectroscopic methods as well as ECD calculation and GIAO 13C NMR calculation. The cytotoxicity of obtained compounds (1-12) was evaluated against human cancer cell lines HL-60, A549, SMMC-7721, MCF-7, and SW480. Compounds 6-8, 11, and 12 showed cytotoxicity with IC50 value ranging from 4.17-37.18 µM.


Assuntos
Antineoplásicos/farmacologia , Citocalasinas/farmacologia , Xylariales/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , China , Citocalasinas/isolamento & purificação , Humanos , Estrutura Molecular , Metabolismo Secundário
6.
World J Microbiol Biotechnol ; 35(7): 109, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31280382

RESUMO

Echinocandin B (ECB) is an important lipohexapeptide used for chemical manufacture of the antifungal agent anidulafungin. Sterigmatocystin (ST) is a polyketide mycotoxin produced by certain species of Aspergillus such as Aspergillus delacroxii SIPIW15, which could produce both ECB and ST. However, the presence of the potent carcinogen ST will greatly affect the quality and safety of ECB production. Therefore, it is essential to eliminate the ST biosynthesis and increase ECB titers in Asp. delacroxii SIPIW15. In this study, the polyketide synthase gene (stcA) required for biosynthesis of ST and its flanking region in Asp. delacroxii SIPIW15 were cloned, sequenced and analyzed firstly. Based on Agrobacterium-mediated transformation, the ΔstcA mutant AMT-1 was obtained and its yield of ECB was increased by 40% without ST detected at the same time as compared to the original strain. The results of the fed-batch experiments showed that the ECB yield of the ΔstcA strain AMT-1 was increased to 2163 ± 31 mg/l and no ST was detected in the 50 l bioreactor. This work suggested that the ΔstcA strain AMT-1 has the potential for application in ECB production improvement, and more importantly, to eliminate ST-related environmental pollution in ECB fermentation industry.


Assuntos
Aspergillus/genética , Aspergillus/metabolismo , Equinocandinas/biossíntese , Equinocandinas/genética , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Genes Fúngicos/genética , Policetídeo Sintases/genética , Esterigmatocistina/biossíntese , Agrobacterium/genética , Anidulafungina , Antifúngicos , Sequência de Bases , Técnicas de Cultura Celular por Lotes , Reatores Biológicos , DNA Fúngico/isolamento & purificação , Fermentação , Engenharia Metabólica , Redes e Vias Metabólicas/genética , Metabolismo Secundário/genética , Transformação Genética
7.
J Microbiol Biotechnol ; 29(7): 1144-1154, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31288301

RESUMO

There have been several studies regarding lichen-associated bacteria obtained from diverse environments. Our screening process identified 49 bacterial species in two lichens from the Himalayas: 17 species of Actinobacteria, 19 species of Firmicutes, and 13 species of Proteobacteria. We discovered five types of strong antimicrobial agent-producing bacteria. Although some strains exhibited weak antimicrobial activity, NP088, NP131, NP132, NP134, and NP160 exhibited strong antimicrobial activity against all multidrug-resistant strains. Polyketide synthase (PKS) fingerprinting revealed results for 69 of 148 strains; these had similar genes, such as fatty acid-related PKS, adenylation domain genes, PfaA, and PksD. Although the association between antimicrobial activity and the PKS fingerprinting results is poorly resolved, NP160 had six types of PKS fingerprinting genes, as well as strong antimicrobial activity. Therefore, we sequenced the draft genome of strain NP160, and predicted its secondary metabolism using antiSMASH version 4.2. NP160 had 46 clusters and was predicted to produce similar secondary metabolites with similarities of 5-100%. Although NP160 had 100% similarity with the alkylresorcinol biosynthetic gene cluster, our results showed low similarity with existing members of this biosynthetic gene cluster, and most have not yet been revealed. In conclusion, we expect that lichen-associated bacteria from the Himalayas can produce new secondary metabolites, and we found several secondary metabolite-related biosynthetic gene clusters to support this hypothesis.


Assuntos
Anti-Infecciosos/metabolismo , Genoma Bacteriano/genética , Líquens/microbiologia , Streptomyces/genética , Streptomyces/metabolismo , Anti-Infecciosos/farmacologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Sequência de Bases , Impressões Digitais de DNA , DNA Bacteriano/genética , Testes de Sensibilidade Microbiana , Família Multigênica , Filogenia , Policetídeo Sintases/genética , RNA Ribossômico 16S/genética , Metabolismo Secundário/genética , Análise de Sequência de DNA
8.
J Agric Food Chem ; 67(34): 9652-9657, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31361133

RESUMO

Plants contain many secondary metabolites, which are sometimes used as spices and herbal medicines. However, the three-dimensional distribution of metabolites is usually unknown. In this study, the spatial distribution of curcumin, one of the main components of dried turmeric root, was examined. Because dried turmeric samples are extremely hard and impossible to section with existing cryomicrotomes, we introduced a new sectioning method and analyzed the two-dimensional distribution of curcumin in turmeric sections cut in different directions. The geometrical analysis of the imaging results suggested that curcumin forms tubular components inside turmeric. The wide-target analysis showed that the spatial distribution of curcumin analogues was similar to that of curcumin. Thus, mass spectrometry imaging was successfully implemented for clarifying the distribution of secondary metabolites in dry plant samples. Understanding the distribution of metabolites inside the plant body might contribute to improving their production processes, including the methods for extraction of active ingredients.


Assuntos
Curcuma/química , Curcumina/química , Extratos Vegetais/química , Raízes de Plantas/química , Curcuma/metabolismo , Curcumina/metabolismo , Espectrometria de Massas , Microscopia , Raízes de Plantas/metabolismo , Metabolismo Secundário
9.
Chemistry ; 25(54): 12644-12651, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31310394

RESUMO

The illudin natural product family are fungal secondary metabolites with a characteristic spirocyclopropyl-substituted fused 6,5-bicyclic ring system. They have been extensively studied for their cytotoxicity in various tumor cell types, and semisynthetic derivatives with improved therapeutic characteristics have progressed to clinical trials. Although it is believed that this potent alkylating compound class acts mainly through DNA modification, little is known about its binding to protein sites in a cellular context. To reveal putative protein targets of the illudin family in live cancer cells, we employed a semisynthetic strategy to access a series of illudin-based probes for activity-based protein profiling (ABPP). While the probes largely retained potent cytotoxicity, proteomic profiling studies unraveled multiple protein hits, suggesting that illudins exert their mode of action not from addressing a specific protein target but rather from DNA modification and unselective protein binding.


Assuntos
Proteínas/química , Proteoma/química , Sesquiterpenos/farmacologia , Compostos de Espiro/farmacologia , Células A549 , Alquilação , Antineoplásicos/química , Antineoplásicos/farmacologia , Sítios de Ligação , Sobrevivência Celular , Humanos , Ligação Proteica , Proteínas/metabolismo , Proteoma/metabolismo , Metabolismo Secundário , Sesquiterpenos/química , Compostos de Espiro/química
10.
Microb Pathog ; 135: 103610, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31288065

RESUMO

The WRKY transcription factors (TFs) family constitutes a major group of TFs in spermatophytes. Different studies have endorsed the considerable biological roles performed by WRKY TFs in plant growth, biotic and abiotic stress responses. Genomic and transcriptomic profiling facilitate us in understanding the WRKY genes in various plants and reveal how WRKY TFs perform their action in response to different plant stresses. WRKY TFs actively take part in metabolism including carbohydrate synthesis, senescence, and secondary metabolites production. Molecular organization of WRKY TFs in plants highlight most predicted outcome of multiple responses simultaneously. Repression and activation related to W-box and other such elements is controlled at transcriptional, translational and domain level. WRKY TFs are becoming more important in crop improvement because of their binding with downstream elements. Additionally, WRKY proteins intermingle with various other TFs for modulating plant immunity. However, WRKY TFs self-regulation and crosstalk between different signaling pathways using WRKY TFs still need extensive investigations. In this review, we focused characteristics of WRKY TFs in Capsicum annum and related research advancement on their functional involvement in plant responses to the challenges of high temperature stress and pathogens infection. We summarized information about Capsicum annum WRKY TFs on the basis of their functions, their target genes and signaling pathways. Moreover, the mechanisms for synergistic responses to various biotic and abiotic stresses, WRKY target genes and other TFs as well will be of more interest with increments in existing information.


Assuntos
Capsicum/genética , Capsicum/imunologia , Imunidade Inata , Imunidade Vegetal/genética , Imunidade Vegetal/imunologia , Estresse Fisiológico/genética , Estresse Fisiológico/imunologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/fisiologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Umidade , Estágios do Ciclo de Vida/fisiologia , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Metabolismo Secundário , Transdução de Sinais , Temperatura Ambiente , Fatores de Transcrição
11.
Biol Res ; 52(1): 39, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358053

RESUMO

In the growth condition(s) of plants, numerous secondary metabolites (SMs) are produced by them to serve variety of cellular functions essential for physiological processes, and recent increasing evidences have implicated stress and defense response signaling in their production. The type and concentration(s) of secondary molecule(s) produced by a plant are determined by the species, genotype, physiology, developmental stage and environmental factors during growth. This suggests the physiological adaptive responses employed by various plant taxonomic groups in coping with the stress and defensive stimuli. The past recent decades had witnessed renewed interest to study abiotic factors that influence secondary metabolism during in vitro and in vivo growth of plants. Application of molecular biology tools and techniques are facilitating understanding the signaling processes and pathways involved in the SMs production at subcellular, cellular, organ and whole plant systems during in vivo and in vitro growth, with application in metabolic engineering of biosynthetic pathways intermediates.


Assuntos
Reguladores de Crescimento de Planta/metabolismo , Fenômenos Fisiológicos Vegetais , Metabolismo Secundário/fisiologia , Estresse Fisiológico/fisiologia , Técnicas de Cultura de Células , Regulação da Expressão Gênica de Plantas/fisiologia , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas/metabolismo , Transdução de Sinais
12.
Environ Sci Pollut Res Int ; 26(25): 26242-26253, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31286371

RESUMO

Heavy-metal contamination of soils has increased in the last decades due to anthropogenic and industrial activities. Arsenic is one of the pollutants that is commonly found in industrial soils and is toxic for both plants and humans. The pH of the soil or the culture medium is one of the most important factors that interferes with the bioavailability of this metalloid to the plant. The addition of chelating agents, such as citric acid (CA), can increase the absorption of As by plants. Therefore, the objective of this work is to study the effect of the pH and the exogenous addition of citric acid on the growth, As accumulation, and thiol compounds in Eupatorium cannabinum; this plant grows naturally in contaminated soils in Asturias, Spain, and has a potential use in phytoremediation. The results showed that E. cannabinum was able to tolerate As stress even at extreme pH values and accumulated a high amounts of As in its roots, which makes it a promising species for the phytostabilization of soils polluted with this metalloid. An addition of 20 mg CA L-1 led to increased biomass and As accumulation at acidic pH. In order to determine if thiolic compounds, such as phytochelatins, are involved in As accumulation and detoxification in E. cannabinum, we analyzed the synthesis of these compounds in the presence and absence of As and/or citric acid. Our results suggest that these thiolic compounds play a major role in As detoxification, since the presence of CA as a chelating agent reduced the amount of thiols necessary to cope with the toxicity caused by As.


Assuntos
Arsênico/análise , Quelantes/análise , Ácido Cítrico/análise , Concentração de Íons de Hidrogênio , Fitoquelatinas/metabolismo , Raízes de Plantas/metabolismo , Biodegradação Ambiental , Quelantes/química , Eupatorium , Humanos , Metabolismo Secundário , Solo , Espanha
13.
Food Chem ; 295: 387-394, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174773

RESUMO

Saffron is appreciated by its colour, taste, and aroma. To examine the effect of abiotic and biotic stress on these main properties, in the span of 2014-2016, saffron stigmas were collected from major different saffron cultivation areas of Iran and saffron quality was estimated. The quality of saffron was assessed by ultraviolet-visible spectroscopy following the ISO3632:2011 standard. However, the composition and concentration of crocetin esters, picrocrocin, safranal, and kaempferols, the most critical compounds determining the properties and quality of saffron can vary with the geographical origin and virus effects, being more accurate High-Performance Liquid Chromatography and Diode Array Detection (HPLC-DAD) methods were used to analyze saffron quality. Using HPLC-DAD we analyzed saffron plants grown at various conditions (considering altitude, temperature, and precipitation/rainfall) and in presence/absence of virus infections; we found that edaphoclimatic and cultivation conditions significantly determine the quality of the spice and the presence of virus modifies the content of its metabolites.


Assuntos
Crocus/química , Crocus/virologia , Análise de Alimentos/métodos , Doenças das Plantas/virologia , Altitude , Carotenoides/análise , Cromatografia Líquida de Alta Pressão , Crocus/metabolismo , Cicloexenos/análise , Qualidade dos Alimentos , Glucosídeos/análise , Irã (Geográfico) , Quempferóis/análise , Extratos Vegetais/química , Chuva , Metabolismo Secundário , Espectrofotometria Ultravioleta , Especiarias/análise , Terpenos/análise
14.
Food Chem ; 295: 412-422, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174776

RESUMO

Consumption of Brassica vegetables is linked to health benefits, as they contain high concentrations of the following secondary plant metabolites (SPMs): glucosinolate breakdown products, carotenoids, chlorophylls, and phenolic compounds. Especially Brassica vegetables are consumed as microgreens (developed cotyledons). It was investigated how different ontogenetic stages (microgreens or leaves) of pak choi (Brassica rapa subsp. chinensis) and kale (Brassica oleracea var. sabellica) differ in their SPM concentration. The impact of breadmaking on SPMs in microgreens (7 days) and leaves (14 days) in pak choi and kale as a supplement in mixed wheat bread was assessed. In leaves, carotenoids, chlorophylls, and phenolic compounds were higher compared to those of microgreens. Breadmaking caused a decrease of SPMs. Chlorophyll degradation was observed, leading to pheophytin and pyropheophytin formation. In kale, sinapoylgentiobiose, a hydroxycinnamic acid derivative, concentration increased. Thus, leaves of Brassica species are suitable as natural ingredients for enhancing bioactive SPM concentrations in bread.


Assuntos
Brassica/metabolismo , Pão , Alimentos Fortificados , Triticum , Brassica rapa/química , Brassica rapa/metabolismo , Carotenoides/análise , Carotenoides/metabolismo , Clorofila/análise , Clorofila/metabolismo , Alimentos Fortificados/análise , Nitrilos , Fenóis/análise , Folhas de Planta/química , Folhas de Planta/metabolismo , Metabolismo Secundário
15.
J Chromatogr A ; 1602: 432-440, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31230874

RESUMO

S. lanata has been traditionally used as a medicinal plant due to its various biological activities such as antioxidant activity. Therefore, identification and quality control studies of this plant are of great importance. To this end, gas chromatography (GC) combined with chemometrics was proposed for fingerprint analysis of S. lanata samples. This study sought to classify GC fingerprints of twenty-eight S. lanata samples from eight different regions of Iran and more importantly, to correlate fingerprints to the antioxidant activity to select S. lanata volatile antioxidant markers. S. lanata samples were classified into five and three classes using partial least squares-discriminant analysis (PLS-DA) according to their GC fingerprints and antioxidant peaks, respectively. The results of PLS regression (PLS-R) and variable importance in projection (VIP) showed that phenol, 2,4-bis (1,1-dimethylethyl)-, hexadecanoic acid- ethyl ester, vitamin E, Beta- sitosterol, and 1- monolinoleoylglycerol trimethylsily ether are volatile antioxidant markers of S. lanata samples.


Assuntos
Antioxidantes/análise , Cromatografia Gasosa/métodos , Metabolismo Secundário , Stachys/metabolismo , Análise Discriminante , Análise dos Mínimos Quadrados , Análise Multivariada , Análise de Componente Principal
16.
J Sci Food Agric ; 99(13): 6011-6019, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31216060

RESUMO

BACKGROUND: The growing area has a substantial effect on plants, affecting secondary metabolism. For hops, different authors have studied the effect of growing area on the chemical composition of cones with the aim of verifying and understanding the changes in hop characters. Despite the scant literature the subject receives increasing attention by brewers and hop growers. The present study aimed to characterize, using gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography with ultraviolet detection (HPLC-UV), cones of hop (Humulus lupulus L.) cultivar Cascade. Plant material was obtained from nine different areas of Italy and compared with Cascade samples grown in the United States, Germany and Slovenia. RESULTS: Differences in bitter acids and xanthohumol content were observed. Nevertheless, no correlation between bitter acids and xanthohumol production, on the one hand, and rainfall, temperatures and latitude, on the other hand, were observed in our samples. The Slovenia samples were richer in molecules that confer hoppy, woody and flower notes; USA2 samples were more characterized by woody, earthy, grassy and floral aroma, quite different characters if compared to USA1, which had the lowest presence of grassy aromatic compounds. In the Italian samples, TRENTINO was the genotype most characterized by limonene presence. CONCLUSION: The results of this study are indicative of the importance for hop users to know and characterize hops coming from different growing regions. The study pays special attention to the characterization of the differences in chemical characters of Cascade hop in Italy, where hop cultivation has developed only recently, but is in continuous expansion. © 2019 Society of Chemical Industry.


Assuntos
Humulus/química , Humulus/crescimento & desenvolvimento , Extratos Vegetais/análise , Ácidos/análise , Ácidos/metabolismo , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Itália , Odorantes/análise , Extratos Vegetais/metabolismo , Propiofenonas/análise , Propiofenonas/metabolismo , Metabolismo Secundário , Paladar
17.
Microbiol Res ; 223-225: 129-136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178045

RESUMO

Heterobasidion annosum s.s. and H. parviporum are severe pathogens of conifers causing butt rot and root rot thus reducing the economic value of timber. Here, the antifungal activity of Bacillus subtilis isolate A18 against these two Heterobasidion species was investigated. Five different culture media with different culture age were investigated to study the effect of substrate composition and culture age for metabolite production. Bacterial cultures and cell-free culture filtrates were tested for antifungal activity. Inhibition of fungal growth was analysed using the agar disc-diffusion method. MALDI-TOF and LC-HRMS analyses were used to identify the antifungal metabolites. Substrate composition and age of culture were found to be active variables with direct effect on the antifungal activity of bacterial culture extracts. High anti-fungal activity was observed when B. subtilis was cultured in PDB, SGB and LB media for four days. Mass-spectrometry analysis showed the presence of lipopeptides in culture filtrates identified as members of the surfactins, polymixins, kurstakins and fengycins. A culture filtrate containing fengycin-type lipopeptides showed the highest bioactivity against Heterobasidion species. Bacterial cultures had higher bioactivity compared to their respective cell free culture filtrates. The results of the present study suggest that B. subtilis A18 is a powerful biocontrol agent against Heterobasidion infections of tree wounds and stumps.


Assuntos
Antifúngicos/farmacologia , Bacillus subtilis/metabolismo , Basidiomycota/efeitos dos fármacos , Basidiomycota/crescimento & desenvolvimento , Agentes de Controle Biológico/metabolismo , Lipopeptídeos/antagonistas & inibidores , Lipopeptídeos/metabolismo , Antifúngicos/isolamento & purificação , Bacillus subtilis/genética , Bacillus subtilis/isolamento & purificação , Basidiomycota/patogenicidade , Agentes de Controle Biológico/isolamento & purificação , Técnicas de Cocultura , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Glucose , Lipopeptídeos/isolamento & purificação , Doenças das Plantas/microbiologia , RNA Ribossômico 16S/genética , Metabolismo Secundário , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
Microbiol Res ; 223-225: 79-87, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31178055

RESUMO

Vibrio parahaemolyticus is a seafood-borne Gram-negative bacteria causing diarrheal diseases in humans world wide. ToxR is a membrane-associated transcriptional factor which plays an important role in acid stress tolerance and regulates the expression of virulence genes including type III secretion system 1 (T3SS1) and type VI secretion system 1 (T6SS1) in V. parahaemolyticus. However, possible mechanisms of ToxR mediating virulence gene expression have not been fully understood. In this study, we demonstrated that ToxR is essential for V. parahaemolyticus to tolerate acid stress by constructing a ToxR deletion mutant (ΔtoxR) and its complemented strain (toxR+). Quantitative PCR showed that the expression of toxR was up regulated under acid stress condition. RNA-seq analysis showed that ompU encoding one of outer membrane proteins was dramatically down regulated in ΔtoxR. Furthermore, the mutation of ompU also led to a significant reduction in tolerating acid stress indicating that ToxR mediated acid stress through regulating ompU expression. RNA-seq results further confirmed that acid stress condition could alter multiple signaling pathways either depending on ToxR (e.g., quorum sensing, fatty acid metabolism) or independent of ToxR (e.g., biosynthesis of secondary metabolites, microbial metabolism in diverse environment, biosynthesis of antibiotics, biosynthesis of amino acids and carbon metabolism pathways). We also for the first time demonstrated that ToxR positively regulated the expression of T6SS2 gene and the interbacteria killing activity. Our study provides comprehensive understanding of signaling pathways which are regulated by both acid stress and ToxR.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação Bacteriana da Expressão Gênica , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Vibrio parahaemolyticus/metabolismo , Adesinas Bacterianas/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Ácidos Graxos/metabolismo , Percepção de Quorum , Metabolismo Secundário , Análise de Sequência de RNA , Deleção de Sequência , Fatores de Transcrição/genética , Transcriptoma , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo VI/genética , Vibrio parahaemolyticus/genética , Vibrio parahaemolyticus/crescimento & desenvolvimento , Virulência/genética
19.
Int J Food Microbiol ; 305: 108243, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31200120

RESUMO

Dry-cured meat products are usually contaminated with moulds during ripening. Although fungal development contributes to the desired sensory characteristics, some moulds, such as Penicillium nordicum are able to produce ochratoxin A (OTA) on meat products. Therefore, strategies to prevent OTA contamination in ripened meat products are required. Microorganisms isolated from these meat products can be adequate as biocontrol agents, given that no negative sensory impact is expected. The PgAFP antifungal protein-producer Penicillium chrysogenum (Pc) and Debaryomyces hansenii (Dh) have been shown to successfully inhibit toxigenic moulds. However, scarce information about the mechanism of action of these biocontrol agents on toxigenic mould inhibition is available. Comparative proteomic analysis is a powerful tool to investigate the physiological response of microorganisms to stimuli. Proteomic analysis was carried out on P. nordicum co-cultured with Pc, Dh, PgAFP, and their combinations on a dry-cured ham-based medium. Additionally, OTA production by P. nordicum in the different cultures was measured. The individual inoculation of Pc or Dh repressed OTA production by P. nordicum by 5 and 3.15 fold, respectively. A total of 2844 unique P. nordicum proteins were identified by proteomic analysis. The impact of the biocontrol agents on the proteome of P. nordicum was higher for Pc-containing cultures, followed by Dh-containing treatments. PgAFP alone had minimal impact on the proteome of P. nordicum. Proteomic analyses indicated Pc repressed P. nordicum OTA production through nutrient competition, potentially reducing glucose availability. Data also suggest that Dh and Pc inhibited P. nordicum through cell wall integrity impairment. Both Pc and Dh seem to hamper P. nordicum secondary metabolism (SM) as indicated by lower levels of MAP kinases and SM-associated proteins found in the co-inoculated P. nordicum. This work paves the way to use antifungal agents in the most efficient way to prevent OTA formation in meat products.


Assuntos
Debaromyces/isolamento & purificação , Proteínas Fúngicas/genética , Produtos da Carne/microbiologia , Ocratoxinas/metabolismo , Penicillium chrysogenum/isolamento & purificação , Penicillium/metabolismo , Animais , Debaromyces/genética , Debaromyces/metabolismo , Microbiologia de Alimentos , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Produtos da Carne/análise , Ocratoxinas/análise , Penicillium/genética , Penicillium/crescimento & desenvolvimento , Penicillium chrysogenum/genética , Penicillium chrysogenum/metabolismo , Proteômica , Metabolismo Secundário , Suínos
20.
Fitoterapia ; 137: 104190, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31163199

RESUMO

The genus Tripterygium belongs to the family Celastraceae, and contains three species, i.e. Tripterygium wilfordii Hook. F, Tripterygium hypoglaucum (Levl.) Hutch. and Tripterygium regelii Sprague et Takeda. All three species are reported to have excellent medicinal properties that help to cure rheumatoid arthritis, nephrotic syndrome, systemic lupus erythematosus and widely used as a folk medicine in China. Phytochemical studies have led to discovering more than 500 secondary metabolites in this genus, including five main types: sesquiterpenoids, diterpenes, triterpenoids, flavonoids, lignans. This work provides structurally grouping statistic of 198 secondary metabolites of Tripterygium species published from 2008 to the present, as well as pharmacological knowledges in the past five years. The information will be helpful for developing the new discoveries of medicinal value related to the genus Tripterygium.


Assuntos
Tripterygium/química , Tripterygium/classificação , Animais , Anti-Inflamatórios/química , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antivirais/química , Diterpenos/química , Flavonoides/química , Humanos , Imunossupressores/química , Lignanas/química , Estrutura Molecular , Fármacos Neuroprotetores/química , Compostos Fitoquímicos/química , Metabolismo Secundário , Sesquiterpenos/química , Triterpenos/química
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