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1.
Plant J ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652034

RESUMO

Barley produces several specialized metabolites, including five α-, ß-, and γ-hydroxynitrile glucosides (HNGs). In malting barley, presence of the α-HNG epiheterodendrin gives rise to undesired formation of ethyl carbamate in the beverage production, especially after distilling. Metabolite-GWAS identified QTLs and underlying gene candidates possibly involved in the control of the relative and absolute content of HNGs, including an undescribed MATE transporter. By screening 325 genetically diverse barley accessions, we discovered three H. vulgare ssp. spontaneum (wild barley) lines with drastic changes in the relative ratios of the five HNGs. Knock-out (KO)-lines, isolated from the barley FIND-IT resource and each lacking one of the functional HNG biosynthetic genes (CYP79A12, CYP71C103, CYP71C113, CYP71U5, UGT85F22 and UGT85F23) showed unprecedented changes in HNG ratios enabling assignment of specific and mutually dependent catalytic functions to the biosynthetic enzymes involved. The highly similar relative ratios between the five HNGs found across wild and domesticated barley accessions indicate assembly of the HNG biosynthetic enzymes in a metabolon, the functional output of which was reconfigured in the absence of a single protein component. The absence or altered ratios of the five HNGs in the KO-lines did not change susceptibility to the fungal phytopathogen Pyrenophora teres causing net blotch. The study provides a deeper understanding of the organization of HNG biosynthesis in barley and identifies a novel, single gene HNG-0 line in an elite spring barley background for direct use in breeding of malting barley, eliminating HNGs as a source of ethyl carbamate formation in whisky production.

2.
Phytochemistry ; 219: 113972, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38211848

RESUMO

Previously undescribed eremane, viscidane, and isozizaene diterpenoids, eremorigidanes A-F, along with six known O-methylated flavonoids and three known triterpenoids were isolated and identified from the leaves of Eremophila rigida Chinnock by combined use of high-resolution PTP1B inhibition profiling, semipreparative- and analytical-scale HPLC separations, HPLC-PDA-HRMS analysis, and NMR spectroscopy. The absolute configuration of the unreported diterpenoids were determined by comparison of their experimental and calculated ECD spectra as well as by biosynthetic arguments. All isolates were evaluated for their PTP1B inhibitory activities, which revealed the flavonoid penduletin (3) to show inhibition with an IC50 value of 18.3 µM, and the triterpenoids 3,4-seco-olean-12-ene-3,28-dioic acid (15), oleanolic acid (16), and 3-oxo-oleanolic acid (17) to show inhibition with IC50 values of 55.7, 9.9, and 6.3 µM, respectively. The preliminary structure-activity relationship (SAR) of isolated flavonoids and triterpenoids is discussed. Plausible biosynthetic steps involved in eremane and isozizaene metabolism are presented and discussed.


Assuntos
Diterpenos , Ácido Oleanólico , Scrophulariaceae , Folhas de Planta/química , Diterpenos/química , Espectroscopia de Ressonância Magnética , Scrophulariaceae/química , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Flavonoides/análise , Estrutura Molecular
3.
J Nat Prod ; 86(12): 2638-2650, 2023 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-38013449

RESUMO

Serrulatanes constitute a class of unique diterpenoids derived from all-Z nerylneryl diphosphate rather than the conventional all-E diterpenoid precursor geranylgeranyl diphosphate and thus provide an intriguing expansion of the chemical space of plant specialized metabolites. Plants of the Australian Eremophila genus are rich sources of structurally diverse serrulatanes. Here, we report the identification of 15 hitherto undescribed serrulatanes (eremoculatanes A-N), together with 16 previously reported compounds, from the EtOAc extract of Eremophila denticulata leaves. Isolation was performed by a combined use of systematic HPLC-PDA-HRMS-based phytochemical profiling and orthogonal reversed-phase C18 and pentafluorophenyl separations. Among the new compounds isolated, eremoculatane A contains a C12 backbone, for which the configuration was established by comparison of experimentally measured and theoretically calculated ECD spectra. The antihyperglycemic and antibacterial activities of the E. denticulata extract were investigated by high-resolution inhibition profiling, and they indicated that major constituents, mainly serrulatanes and flavonoids, contributed to the observed activity of the extract. One flavonoid, eupafolin (4), displayed moderate α-glucosidase inhibitory activity with an IC50 value of 41.3 µM, and four serrulatanes (8, 9, 19g, and 19j) showed more than 50% PTP1B inhibition at 200 µM.


Assuntos
Extratos Vegetais , Scrophulariaceae , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Austrália , Hipoglicemiantes/química , Flavonoides , Compostos Fitoquímicos , Scrophulariaceae/química
4.
Bioorg Chem ; 139: 106744, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37517158

RESUMO

In this study, an extract of the leaves of Eremophila clarkei Oldfield & F.Muell. showed protein tyrosine phosphatase 1B (PTP1B) inhibitory activity with an IC50 value of 33.0 µg/mL. The extract was therefore investigated by high-resolution PTP1B inhibition profiling to pinpoint the constituents responsible for the activity. Subsequent isolation and purification using analytical-scale HPLC led to identification of eight previously undescribed decipiene diterpenoids, eremoclarkanes A-H, as well as eremoclarkic acid, a biogenetically related new phenolic acid. In addition, one known decipiene diterpenoid and ten known O-methylated flavonoids were isolated. The structures of the isolated compounds were elucidated by extensive analysis of their HRMS and 1D and 2D NMR spectra. The absolute configuration of decipiene diterpenoids was determined by comparison of experimental and calculated ECD spectra. The flavonoid hispidulin (2b) and the four decipiene diterpenoids 13a, 13b, 13f, and 14b exhibited PTP1B inhibitory activity with IC50 values ranging from 22.8 to 33.6 µM. This is the first report of PTP1B inhibitory activity of decipienes, and enzyme kinetics revealed that 13a and 13b are competitive inhibitors of PTP1B, whereas 13f and 14b displayed mixed-type-mode inhibition of PTP1B. Finally, molecular docking indicated that 13a, 13b, 13f, and 14b showed comparable binding affinity towards the active and/or allosteric site of PTP1B enzyme. Structure-activity relationship (SAR) of the identified O-methylated flavonoids and decipiene diterpenoids towards PTP1B is discussed. Plausible enzymatic and photochemically driven routes for the formation of the decipienes and conversion products thereof are presented and discussed.


Assuntos
Diterpenos , Extratos Vegetais , Simulação de Acoplamento Molecular , Cinética , Extratos Vegetais/química , Flavonoides , Diterpenos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Inibidores Enzimáticos/química
5.
Nat Chem ; 15(9): 1236-1246, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37365337

RESUMO

Obesity is a major health risk still lacking effective pharmacological treatment. A potent anti-obesity agent, celastrol, has been identified in the roots of Tripterygium wilfordii. However, an efficient synthetic method is required to better explore its biological utility. Here we elucidate the 11 missing steps for the celastrol biosynthetic route to enable its de novo biosynthesis in yeast. First, we reveal the cytochrome P450 enzymes that catalyse the four oxidation steps that produce the key intermediate celastrogenic acid. Subsequently, we show that non-enzymatic decarboxylation-triggered activation of celastrogenic acid leads to a cascade of tandem catechol oxidation-driven double-bond extension events that generate the characteristic quinone methide moiety of celastrol. Using this acquired knowledge, we have developed a method for producing celastrol starting from table sugar. This work highlights the effectiveness of combining plant biochemistry with metabolic engineering and chemistry for the scalable synthesis of complex specialized metabolites.


Assuntos
Fármacos Antiobesidade , Triterpenos , Triterpenos/química , Triterpenos/metabolismo , Triterpenos/farmacologia , Fármacos Antiobesidade/farmacologia , Triterpenos Pentacíclicos , Sistema Enzimático do Citocromo P-450
6.
J Nat Prod ; 86(4): 694-709, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36880726

RESUMO

Extracts of Eremophila phyllopoda subsp. phyllopoda showed α-glucosidase and PTP1B inhibitory activity with IC50 values of 19.6 and 13.6 µg/mL, respectively. High-resolution α-glucosidase/PTP1B/radical scavenging profiling was performed to establish a triple high-resolution inhibition profile that allowed direct pinpointing of the constituents responsible for one or more of the observed bioactivities. Subsequent targeted isolation and purification by analytical-scale HPLC led to the identification of 21 previously undescribed serrulatane diterpenoids, eremophyllanes A-U, as well as two known serrulatane diterpenoids, 1ß-trihydroxyserrulatane (8) and 1α-trihydroxyserrulatane (10d), and five known furofuran lignans, (+)-piperitol (6), horsfieldin (7e), (-)-sesamin (9), (+)-sesamin (10h), and asarinin (10i). Their structures were elucidated by extensive analysis of HRMS and 1D and 2D NMR spectroscopic data. The relative configurations of the previously undescribed compounds were established by analysis of ROESY spectra as well as by DFT-GIAO NMR calculations followed by DP4+ probability analysis. The absolute configurations were determined by comparison of experimental and calculated ECD spectra. Serrulatane diterpenoids 7b and 14 exhibited α-glucosidase inhibitory activity with IC50 values of 28.4 and 64.2 µM, respectively, while 11, 12, 14, and 15 exhibited PTP1B inhibitory activity with IC50 values ranging from 16.6 to 104.6 µM. Hypothetical routes for formation of all identified serrulatane diterpenoids are proposed.


Assuntos
Diterpenos , Scrophulariaceae , alfa-Glucosidases/metabolismo , Dicroísmo Circular , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Scrophulariaceae/química
7.
Anal Chem ; 95(9): 4381-4389, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36802535

RESUMO

Discovery of sustainable and benign-by-design drugs to combat emerging health pandemics calls for new analytical technologies to explore the chemical and pharmacological properties of Nature's unique chemical space. Here, we present a new analytical technology workflow, polypharmacology-labeled molecular networking (PLMN), where merged positive and negative ionization tandem mass spectrometry-based molecular networking is linked with data from polypharmacological high-resolution inhibition profiling for easy and fast identification of individual bioactive constituents in complex extracts. The crude extract of Eremophila rugosa was subjected to PLMN analysis for the identification of antihyperglycemic and antibacterial constituents. Visually easy-interpretable polypharmacology scores and polypharmacology pie charts as well as microfractionation variation scores of each node in the molecular network provided direct information about each constituent's activity in the seven assays included in this proof-of-concept study. A total of 27 new non-canonical nerylneryl diphosphate-derived diterpenoids were identified. Serrulatane ferulate esters were shown to be associated with antihyperglycemic and antibacterial activities, including some showing synergistic activity with oxacillin in clinically relevant (epidemic) methicillin-resistant Staphylococcus aureus strains and some showing saddle-shaped binding to the active site of protein-tyrosine phosphatase 1B. PLMN is scalable in the number and types of assays included and thus holds potential for a paradigm shift toward polypharmacological natural-products-based drug discovery.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Polifarmacologia , Fluxo de Trabalho , Antibacterianos/farmacologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química
8.
New Phytol ; 237(3): 999-1013, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36305250

RESUMO

The economic and ecologically important genus Eucalyptus is rich in structurally diverse specialized metabolites. While some specialized metabolite classes are highly prevalent across the genus, the cyanogenic glucoside prunasin is only produced by c. 3% of species. To investigate the evolutionary mechanisms behind prunasin biosynthesis in Eucalyptus, we compared de novo assembled transcriptomes, together with online resources between cyanogenic and acyanogenic species. Identified genes were characterized in vivo and in vitro. Pathway characterization of cyanogenic Eucalyptus camphora and Eucalyptus yarraensis showed for the first time that the final glucosylation step from mandelonitrile to prunasin is catalyzed by a novel UDP-glucosyltransferase UGT87. This step is typically catalyzed by a member of the UGT85 family, including in Eucalyptus cladocalyx. The upstream conversion of phenylalanine to mandelonitrile is catalyzed by three cytochrome P450 (CYP) enzymes from the CYP79, CYP706, and CYP71 families, as previously shown. Analysis of acyanogenic Eucalyptus species revealed the loss of different ortholog prunasin biosynthetic genes. The recruitment of UGTs from different families for prunasin biosynthesis in Eucalyptus demonstrates important pathway heterogeneities and unprecedented dynamic pathway evolution of chemical defense within a single genus. Overall, this study provides relevant insights into the tremendous adaptability of these long-lived trees.


Assuntos
Eucalyptus , Eucalyptus/genética , Eucalyptus/metabolismo , Nitrilas/química , Nitrilas/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Difosfato de Uridina/metabolismo
9.
Nat Commun ; 13(1): 5143, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050299

RESUMO

The ginkgo tree (Ginkgo biloba) is considered a living fossil due to its 200 million year's history under morphological stasis. Its resilience is partly attributed to its unique set of specialized metabolites, in particular, ginkgolides and bilobalide, which are chemically complex terpene trilactones. Here, we use a gene cluster-guided mining approach in combination with co-expression analysis to reveal the primary steps in ginkgolide biosynthesis. We show that five multifunctional cytochrome P450s with atypical catalytic activities generate the tert-butyl group and one of the lactone rings, characteristic of all G. biloba trilactone terpenoids. The reactions include scarless C-C bond cleavage as well as carbon skeleton rearrangement (NIH shift) occurring on a previously unsuspected intermediate. The cytochrome P450s belong to CYP families that diversifies in pre-seed plants and gymnosperms, but are not preserved in angiosperms. Our work uncovers the early ginkgolide pathway and offers a glance into the biosynthesis of terpenoids of the Mesozoic Era.


Assuntos
Sistema Enzimático do Citocromo P-450 , Ginkgo biloba , Ginkgolídeos , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Ginkgo biloba/genética , Ginkgo biloba/metabolismo , Ginkgolídeos/química , Humanos , Lactonas/metabolismo , Família Multigênica , Extratos Vegetais/química , Terpenos
10.
Phytochemistry ; 203: 113408, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36063865

RESUMO

The plant genus Eremophila is endemic to Australia and widespread in arid regions. Root bark extract of Eremophila longifolia (R.Br.) F.Muell. (Scrophulariaceae) was investigated by LC-PDA-HRMS, and dereplication suggested the presence of a series of diterpenoids. Using a combination of preparative- and analytical-scale HPLC separation as well as extensive 1D and 2D NMR analysis, the structures of 12 hitherto unreported serrulatane diterpenoids, eremolongine A-L, were established. These structures included serrulatanes with unusual side chain modifications to form hitherto unseen skeletons with, e.g., cyclopentane, oxepane, and bicyclic hexahydro-1H-cyclopenta[c]furan moieties. Serrulatane diterpenoids in Eremophila have recently been shown to originate from a common biosynthetic precursor with conserved stereochemical configuration, and this was used for tentative assignment of the relative and absolute configuration of the isolated compounds. Triple high-resolution α-glucosidase/α-amylase/PTP1B inhibition profiling demonstrated that several of the eremolongines had weak inhibitory activity towards targets important for management of type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Diterpenos , Scrophulariaceae , Ciclopentanos , Diterpenos/farmacologia , Furanos/química , Casca de Planta , Extratos Vegetais/química , Scrophulariaceae/química , alfa-Amilases , alfa-Glucosidases
11.
Nat Commun ; 13(1): 5011, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008399

RESUMO

The diterpenoid triepoxides triptolide and triptonide from Tripterygium wilfordii (thunder god wine) exhibit unique bioactivities with potential uses in disease treatment and as a non-hormonal male contraceptives. Here, we show that cytochrome P450s (CYPs) from the CYP71BE subfamily catalyze an unprecedented 18(4→3) methyl shift required for biosynthesis of the abeo-abietane core structure present in diterpenoid triepoxides and in several other plant diterpenoids. In combination with two CYPs of the CYP82D subfamily, four CYPs from T. wilfordii are shown to constitute the minimal set of biosynthetic genes that enables triptonide biosynthesis using Nicotiana benthamiana and Saccharomyces cerevisiae as heterologous hosts. In addition, co-expression of a specific T. wilfordii cytochrome b5 (Twcytb5-A) increases triptonide output more than 9-fold in S. cerevisiae and affords isolation and structure elucidation by NMR spectroscopic analyses of 18 diterpenoids, providing insights into the biosynthesis of diterpenoid triepoxides. Our findings pave the way for diterpenoid triepoxide production via fermentation.


Assuntos
Diterpenos , Tripterygium , Sistema Enzimático do Citocromo P-450/genética , Diterpenos/química , Saccharomyces cerevisiae/genética , Tripterygium/genética , Triterpenos
12.
Sci Adv ; 8(34): eabq2266, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36001660

RESUMO

Improved agricultural and industrial production organisms are required to meet the future global food demands and minimize the effects of climate change. A new resource for crop and microbe improvement, designated FIND-IT (Fast Identification of Nucleotide variants by droplet DigITal PCR), provides ultrafast identification and isolation of predetermined, targeted genetic variants in a screening cycle of less than 10 days. Using large-scale sample pooling in combination with droplet digital PCR (ddPCR) greatly increases the size of low-mutation density and screenable variant libraries and the probability of identifying the variant of interest. The method is validated by screening variant libraries totaling 500,000 barley (Hordeum vulgare) individuals and isolating more than 125 targeted barley gene knockout lines and miRNA or promoter variants enabling functional gene analysis. FIND-IT variants are directly applicable to elite breeding pipelines and minimize time-consuming technical steps to accelerate the evolution of germplasm.

13.
Plant J ; 111(4): 936-953, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35696314

RESUMO

In a cross-continental research initiative, including researchers working in Australia and Denmark, and based on joint external funding by a 3-year grant from the Novo Nordisk Foundation, we have used DNA sequencing, extensive chemical profiling and molecular networking analyses across the entire Eremophila genus to provide new knowledge on the presence of natural products and their bioactivities using polypharmocological screens. Sesquiterpenoids, diterpenoids and dimers of branched-chain fatty acids with previously unknown chemical structures were identified. The collection of plant material from the Eremophila genus was carried out according to a 'bioprospecting agreement' with the Government of Western Australia. We recognize that several Eremophila species hold immense cultural significance to Australia's First Peoples. In spite of our best intentions to ensure that new knowledge gained about the genus Eremophila and any potential future benefits are shared in an equitable manner, in accordance with the Nagoya Protocol, we encounter serious dilemmas and potential conflicts in making benefit sharing with Australia's First Peoples a reality.


Assuntos
Diterpenos , Scrophulariaceae , Austrália
14.
Trends Plant Sci ; 27(7): 655-673, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35396170

RESUMO

Using synthetic biology, it is now time to expand the biosynthetic repertoire of plants and microalgae by utilizing the chloroplast to augment the production of desired high-value compounds and of oil-, carbohydrate-, or protein-enriched biomass based on direct harvesting of solar energy and the consumption of CO2. Multistream product lines based on separate commercialization of the isolated high-value compounds and of the improved bulk products increase the economic potential of the light-driven production system and accelerate commercial scale up. Here we outline the scientific basis for the establishment of such green circular biomanufacturing systems and highlight recent results that make this a realistic option based on cross-disciplinary basic and applied research to advance long-term solutions.


Assuntos
Microalgas , Energia Solar , Biomassa , Dióxido de Carbono/metabolismo , Cloroplastos/metabolismo , Fotossíntese
15.
Genes (Basel) ; 13(1)2022 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-35052482

RESUMO

Domestication has resulted in a loss of genetic diversity in our major food crops, leading to susceptibility to biotic and abiotic stresses linked with climate change. Crop wild relatives (CWR) may provide a source of novel genes potentially important for re-gaining climate resilience. Sorghum bicolor is an important cereal crop with wild relatives that are endemic to Australia. Sorghum bicolor is cyanogenic, but the cyanogenic status of wild Sorghum species is not well known. In this study, leaves of wild species endemic in Australia are screened for the presence of the cyanogenic glucoside dhurrin. The direct measurement of dhurrin content and the potential for dhurrin-derived HCN release (HCNp) showed that all the tested Australian wild species were essentially phenotypically acyanogenic. The unexpected low dhurrin content may reflect the variable and generally nutrient-poor environments in which they are growing in nature. Genome sequencing of six CWR and PCR amplification of the CYP79A1 gene from additional species showed that a high conservation of key amino acids is required for correct protein function and dhurrin synthesis, pointing to the transcriptional regulation of the cyanogenic phenotype in wild sorghum as previously shown in elite sorghum.


Assuntos
Glicosídeos/metabolismo , Cianeto de Hidrogênio/metabolismo , Nitrilas/metabolismo , Proteínas de Plantas/metabolismo , Sorghum/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Genótipo , Fenótipo , Proteínas de Plantas/genética , Sorghum/genética , Sorghum/crescimento & desenvolvimento
16.
Planta ; 255(2): 51, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35084593

RESUMO

MAIN CONCLUSION: Australian native species of sorghum contain negligible amounts of dhurrin in their leaves and the cyanogenesis process is regulated differently under water-stress in comparison to domesticated sorghum species. Cyanogenesis in forage sorghum is a major concern in agriculture as the leaves of domesticated sorghum are potentially toxic to livestock, especially at times of drought which induces increased production of the cyanogenic glucoside dhurrin. The wild sorghum species endemic to Australia have a negligible content of dhurrin in the above ground tissues and thus represent a potential resource for key agricultural traits like low toxicity. In this study we investigated the differential expression of cyanogenesis related genes in the leaf tissue of the domesticated species Sorghum bicolor and the Australian native wild species Sorghum macrospermum grown in glasshouse-controlled water-stress conditions using RNA-Seq analysis to analyse gene expression. The study identified genes, including those in the cyanogenesis pathway, that were differentially regulated in response to water-stress in domesticated and wild sorghum. In the domesticated sorghum, dhurrin content was significantly higher compared to that in the wild sorghum and increased with stress and decreased with age whereas in wild sorghum the dhurrin content remained negligible. The key genes in dhurrin biosynthesis, CYP79A1, CYP71E1 and UGT85B1, were shown to be highly expressed in S. bicolor. DHR and HNL encoding the dhurrinase and α-hydroxynitrilase catalysing bio-activation of dhurrin were also highly expressed in S. bicolor. Analysis of the differences in expression of cyanogenesis related genes between domesticated and wild sorghum species may allow the use of these genetic resources to produce more acyanogenic varieties in the future.


Assuntos
Sorghum , Austrália , Grão Comestível , Nitrilas , Sorghum/genética , Água
17.
Phytochemistry ; 196: 113072, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34973506

RESUMO

Eremophila (Scrophulariaceae) is a genus of Australian desert plants, which have been used by Australian Aboriginal people for various medicinal purposes. Crude extracts of the leaf resin of Eremophila glabra (R.Br.) Ostenf. showed α-glucosidase and protein tyrosine phosphatase 1B (PTP1B) inhibitory activity with IC50 values of 19.3 ± 1.2 µg/mL and 11.8 ± 2.1 µg/mL, respectively. Dual α-glucosidase/PTP1B high-resolution inhibition profiling combined with HPLC-PDA-HRMS and NMR were used to isolate and identify the compounds providing these activities. This resulted in isolation of seven undescribed serrulatane diterpenoids, eremoglabrane A-G, together with nine previously identified serrulatane diterpenoids and flavonoids. Three of the serrulatane diterpenoids showed PTP1B inhibitory activities with IC50 values from 63.8 ± 5.8 µM to 104.5 ± 25.9 µM.


Assuntos
Diterpenos , Scrophulariaceae , Austrália , Diterpenos/química , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Scrophulariaceae/química
18.
Gesundheitswesen ; 84(10): 961-967, 2022 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-34161985

RESUMO

BACKGROUND: The GERDA ("Protected e-prescription service for pharmacies") project of the Chamber of Pharmacists (LAK) and Pharmacists Association (LAV) of the federal state of Baden-Wuerttemberg provided the opportunity to prescribe medications within the telemedical portal "docdirekt" that is operated by the Association of Statutory Health Insurance Physicians of Baden-Wuerttemberg. Against this background, the aim of the study was to explore and prioritize barriers and enablers among pharmacists to participate in a medical supply system that includes electronic prescriptions (e-prescriptions). Based on these determinants, recommendations for optimizing the successful implementation of similar care offers were derived. METHOD: A mixed methods design was chosen to explore and prioritize the determinants. In the first step, determinants for participation in an electronic prescribing system were explored by means of individual interviews of docdirekt tele-physicians, primary care physicians and pharmacists. In a second step, these determinants were prioritized through a quantitative survey of pharmacists. RESULTS: Out of the 523 pharmacists that answered the questionnaire, more than half were willing to participate in an e-prescription system, while 8.5% excluded future participation. A total of 18 determinants for the e-prescription system participation could be explored. The protection of the free pharmacy choice for the patients was identified as the most important determinant, followed by the option of a correction function for e-prescriptions (e. g. to avoid retaxing or medication errors), the integration of the e-prescription into the existing pharmacy IT system and the statutory exclusion of direct contracts with online pharmacies. Time savings and possibly higher remunerations were rated as less relevant. CONCLUSION: More than half of the pharmacies surveyed stated that they wanted to participate in an e-prescription system. Widespread introduction of e-prescriptions in planned for January 2022. Successful implementation of this move will be facilitated if the identified determinants are taken into consideration by politics, software developers and associations.


Assuntos
Prescrição Eletrônica , Farmácias , Estudos Transversais , Alemanha , Humanos , Farmacêuticos
19.
Planta ; 254(6): 119, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34762174

RESUMO

MAIN CONCLUSION: Developmental and organ-specific expression of genes in dhurrin biosynthesis, bio-activation, and recycling offers dynamic metabolic responses optimizing growth and defence responses in Sorghum. Plant defence models evaluate the costs and benefits of resource investments at different stages in the life cycle. Poor understanding of the molecular regulation of defence deployment and remobilization hampers accuracy of the predictions. Cyanogenic glucosides, such as dhurrin are phytoanticipins that release hydrogen cyanide upon bio-activation. In this study, RNA-seq was used to investigate the expression of genes involved in the biosynthesis, bio-activation and recycling of dhurrin in Sorghum bicolor. Genes involved in dhurrin biosynthesis were highly expressed in all young developing vegetative tissues (leaves, leaf sheath, roots, stems), tiller buds and imbibing seeds and showed gene specific peaks of expression in leaves during diel cycles. Genes involved in dhurrin bio-activation were expressed early in organ development with organ-specific expression patterns. Genes involved in recycling were expressed at similar levels in the different organ during development, although post-floral initiation when nutrients are remobilized for grain filling, expression of GSTL1 decreased > tenfold in leaves and NITB2 increased > tenfold in stems. Results are consistent with the establishment of a pre-emptive defence in young tissues and regulated recycling related to organ senescence and increased demand for nitrogen during grain filling. This detailed characterization of the transcriptional regulation of dhurrin biosynthesis, bioactivation and remobilization genes during organ and plant development will aid elucidation of gene regulatory networks and signalling pathways that modulate gene expression and dhurrin levels. In-depth knowledge of dhurrin metabolism could improve the yield, nitrogen use efficiency and stress resilience of Sorghum.


Assuntos
Sorghum , Expressão Gênica , Glicosídeos , Nitrilas , Sorghum/genética
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