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1.
J Chromatogr A ; 1637: 461733, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33385745

RESUMO

A hydrophilic interaction (HILIC) ultra-high performance liquid chromatography (UHPLC) with triple quadrupole tandem mass spectrometry (MS/MS) method was developed and validated for the quantification of 21 free amino acids (AAs). Compared to published reports, our method renders collectively improved sensitivity with lower limit of quantification (LLOQ) at 0.5~42.19 ng/mL with 0.3 µL injection volume (or equivalently 0.15~12.6 pg injected on column), robust linear range from LLOQ up to 3521~5720 ng/mL (or 1056 ~ 1716 pg on column) and a high throughput with total time of 6 min per sample, as well as easier experimental setup, less maintenance and higher adaptation flexibility. Ammonium formate in the mobile phase, though commonly used in HILIC, was found unnecessary in our experimental setup, and its removal from mobile phase was key for significant improvement in sensitivity (4~74 times higher than with 5 mM ammonium formate). Addition of 10 (or up to100 mM) hydrochloric acid (HCl) in the sample diluent was crucial to keep response linearity for basic amino acids of histidine, lysine and arginine. Different HCl concentration (10~100 mM) in sample diluent also excreted an effect on detection sensitivity, and it is of importance to keep the final prepared sample and calibrators in the same HCl level. Leucine and isoleucine were distinguished using different transitions. Validated at seven concentration levels, accuracy was bound within 75~125%, matrix effect generally within 90~110%, and precision error mostly below 2.5%. Using this newly developed method, the free amino acids were then quantified in a total of 544 African indigenous vegetables (AIVs) samples from African nightshades (AN), Ethiopian mustards (EM), amaranths (AM) and spider plants (SP), comprising a total of 8 identified species and 43 accessions, cultivated and harvested in USA, Kenya and Tanzania over several years, 2013~2018. The AN, EM, AM and SP were distinguished based on free AAs profile using machine learning methods (ML) including principle component analysis, discriminant analysis, naïve Bayes, elastic net-regularized logistic regression, random forest and support vector machine, with prediction accuracy achieved at ca. 83~97% on the test set (train/test ratio at 7/3). An interactive ML platform was constructed using R Shiny at https://boyuan.shinyapps.io/AIV_Classifier/ for modeling train-test simulation and category prediction of unknown AIV sample(s). This new method presents a robust and rapid approach to quantifying free amino acids in plants for use in evaluating plants, biofortification, botanical authentication, safety, adulteration and with applications to nutrition, health and food product development.


Assuntos
Aminoácidos/análise , Cromatografia Líquida de Alta Pressão/métodos , Aprendizado de Máquina , Espectrometria de Massas em Tandem/métodos , Verduras/química , Teorema de Bayes , Humanos , Interações Hidrofóbicas e Hidrofílicas , Análise de Componente Principal , Reprodutibilidade dos Testes
2.
J Med Entomol ; 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33140831

RESUMO

The common bed bug, Cimex lectularius L., resurged as an important urban pest in the last 20 yr. Yet, there are no commercial repellent products labeled for bed bugs available in the United States. We evaluated the repellency of two catnip oils from newly developed cultivars, CR3 and CR9, and compared each to 10 and 25% N,N-diethyl-meta-toluamide (DEET). CR3 contains 63.4% E,Z-nepatalactone and 27.5% Z,E-nepatalactone, and CR9 contains 94.9% Z,E-nepatalactone. Arena studies showed that CR3 and CR9 oils were more effective than DEET within a 24-h period. At 10% concentration, both CR3 and CR9 oils exhibited a repellency of over 94% during the first 8 h. At 25% concentration, the repellency of CR3 and CR9 oils increased to 100%, and repellency of DEET was 92% during the first 24 h. Repellency of 25% CR3 and CR9 oils became lower than 25% DEET after being aged for 3 d. After 28-d aging, repellency of 25% CR3, CR9, and DEET reduced to 25, 64, and 92%, respectively. Soiled socks were placed above repellent treated bands to determine if the repellent can protect soiled socks from being infested. The 20% CR3 oil prevented 100% of bed bugs from infesting soiled socks showing that it was more effective than DEET. These results indicate that catnip oils from CR3 and CR9 cultivars are more repellent than DEET over a 24-h period following application, but their longevity is shorter than DEET after 72 h.

3.
Molecules ; 25(19)2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007965

RESUMO

The first total synthesis of novel skeleton natural compounds kinkeloids A and B, a group of newly discovered flavan alkaloids isolated from the African plant Combretum micranthum, are described in this study. The key and final step are achieved by Mannich reaction, through which the piperidine moiety couples to the flavan moiety. The identities of synthesized kinkeloids were further confirmed through a comparison with the ones in the plant leaves extract using LC/MS.

4.
Rapid Commun Mass Spectrom ; 34(19): e8882, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32644256

RESUMO

RATIONALE: The safe consumption of Solanum scabrum and S. nigrum berries (SNBs) depends on a reliable and rapid chemical screen for the testing of the fruit and/or final food and industrial products for the presence and level of toxic glycoalkaloids. Such a rapid and sensitive screen could also be used by those involved in food safety and forensics, industry, research labs and those in agriculture production, breeding and food processing. Significant variation in the content and composition of glycoalkaloids across SNBs has been reported. To facilitate high-throughput targeted analysis, this work overcame the slow scan speed of a traditional triple quadruple mass spectrometry (QqQ) method by development of a pseudo-MS3 method. METHODS: In-source fragmentation functioned as a pseudo-MS or pseudo-hydrolysis to trim down the structurally diverse and complex glycosides into five types of aglycone ions, which were then analyzed using multiple reaction monitoring (MRM). Characteristic product ions were selected based on the aglycone skeleton and substitution pattern and associated fragmentation pathway. RESULTS: A compact method with only 15 MRM transitions were developed for high-throughput screening of very diverse glycoalkaloids. Glycosides of the same aglycone type were readily identified in the same transition window without the need for mass spectra interpretation. Validated using solamargine, the sole available standard, the accuracy was 99.7-101.3%, the intra- and inter-day precision were, respectively, 2.5-5.0% and 8.0-9.2%, and the lower limit of detection and quantification were, respectively, 3.1 and 10.2 ng/mL (with 1 µL injection volume). CONCLUSIONS: The peudo-MS3 method allowed for high-throughput targeted analysis with compact MRM transitions to address a large number of glycoalkaloids with diverse structures. This method could serve to meet the most heavy-duty demand for rapid inspection of glycoalkaloids in SNBs. This method can be adopted and used by those involved in food safety and forensics, in developing food and industrial products and in genetics and breeding.

5.
Transl Psychiatry ; 10(1): 183, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518327

RESUMO

Major depressive disorder (MDD) is a leading cause of disability, and there is an urgent need for new therapeutics. Stress-mediated induction of pro-inflammation in the periphery contributes to depression-like behaviors both in humans and in experimental models. Inflammatory cytokine interleukin-6 (IL-6) has emerged as a potential therapeutic target. Our studies demonstrated that metabolism of flavanol rich cocoa preparation (FRP) led to the accumulation of select phenolic acids that may contribute to its anti-inflammatory activity. Using a repeated social defeat stress (RSDS) model of depression, we showed that oral administration of FRP attenuates susceptibility to RSDS-mediated depression, supporting the further development of FRP as a novel therapeutic for the treatment of stress disorders and anxiety in humans.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32474352

RESUMO

Raspberry ketone (RK) (4-(4-hydroxyphenyl)-2-butanone) is the major compound responsible for the characteristic aroma of red raspberries, and has long been used commercially as a flavoring agent and recently as a weight loss supplement. A targeted UHPLC-QqQ-MS/MS method was developed and validated for analysis of RK and 25 associated metabolites in mouse plasma and brain. Dispersion and projection analysis and central composite design were used for method optimization. Random effect analysis of variance was applied for validation inference and variation partition. Within this framework, repeatability, a broader sense of precision, was calculated as fraction of accuracy variance, reflecting instrumental imprecision, compound degradation and carry-over effects. Multivariate correlation analysis and principle component analysis were conducted, revealing underlying association among the manifold of method traits. R programming was engaged in streamlined statistical analysis and data visualization. Two particular phenomena, the analytes' background existence in the enzyme solution used for phase II metabolites deconjugation, and the noted lability of analytes in pure solvent at 4 ℃ vs. elevated stability in biomatrices, were found critical to method development and validation. The approach for the method development and validation provided a foundation for experiments that examine RK metabolism and bioavailability.

7.
Mol Nutr Food Res ; 64(8): e1900907, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32052560

RESUMO

OBJECTIVES: Raspberry ketone (RK) is the primary aroma compound in red raspberries and a dietary supplement for weight loss. This work aims to 1) compare RK bioavailability in male versus female, normal-weight versus obese mice; 2) characterize RK metabolic pathways. METHODS: Study 1: C57BL/6J male and female mice fed a low-fat diet (LFD; 10% fat) receive a single oral gavage dose of RK (200 mg kg-1 ). Blood, brain, and white adipose tissue (WAT) are collected over 12 h. Study 2: Male mice are fed a LFD or high-fat diet (45% fat) for 8 weeks before RK dosing. Samples collected are analyzed by UPLC-MS/MS for RK and its metabolites. RESULTS: RK is rapidly absorbed (Tmax  ≈ 15 min), and bioconverted into diverse metabolites in mice. Total bioavailability (AUC0-12 h ) is slightly lower in females than males (566 vs 675 nmol mL-1 min-1 ). Total bioavailability in obese mice is almost doubled that of control mice (1197 vs 679 nmol mL-1 min-1 ), while peaking times and elimination half-lives are delayed. Higher levels of RK and major metabolites are found in WAT of the obese than normal-weight animals. CONCLUSIONS: RK is highly bioavailable, rapidly metabolized, and exhibits significantly different pharmacokinetic behaviors between obese and control mice. Lipid-rich tissues, especially WAT, can be a direct target of RK.

8.
Food Chem ; 312: 126030, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31911353

RESUMO

This study developed comprehensive quantification methods for major nutritive and antinutritive phytochemical aglycones in edible African nightshade leaves, an underutilized food resource in the sub-Saharan area. A simultaneous hydrolysis and extraction method was developed using methanol with 2 M sulfuric acid with incubation at 65 °C for 60 min. UHPLC-QqQ-MS/MS methods were developed and validated for hydrolysis optimization and for quantification of eight major aglycones of polyphenols, alkaloids and sapogenins in 20 differently sourced nightshade leaves, comprising two African species Solanum scabrum and S. nigrum, and from two distinct cultivation sites, one in New Jersey, US and the other in Kenya Eldoret. Variation in species, accessions and cultivation environment played an important role in affecting the phytochemical profile. Total antinutritive alkaloids and sapogenins in all nightshade leaves were evaluated and found to be safe for consumption. This work provides evidence that the consumption of African nightshade leaves as a nutrient rich leafy green vegetable is safe and can contribute to food security and nutritional improvement in the sub-Saharan area.


Assuntos
Alcaloides/análise , Polifenóis/análise , Saponinas/análise , Solanum/química , Cromatografia Líquida de Alta Pressão/métodos , Glicosilação , Hidrólise , Quênia , Análise Multivariada , Folhas de Planta/química , Espectrometria de Massas em Tandem
9.
Crit Rev Food Sci Nutr ; 60(4): 597-625, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30614258

RESUMO

The aging of populations worldwide is driving greater demands for dietary polyphenols which have been recognized as promising prophylactic and/or therapeutic agents in the context of neurodegeneration, and are ubiquitously present in plant-based diets. In particular, grape-derived products encompass a wide array of phenolic compounds purported with multiple health benefits including neuroprotective efficacy. Despite the increasing preclinical and clinical evidence demonstrating high potential of grape polyphenol (GPP)-rich botanicals in preventing and attenuating diverse neurodegenerative disorders, the limited bioavailability of GPPs, especially in the brain, generates questions as to their applications and effectiveness in neuroprotection. To address this issue, significant research efforts have been made to enhance oral bioavailability of GPPs via application of novel strategies. This review highlights some critical issues related to the bioavailability and neuroprotective efficacy of GPPs and GPP-rich botanicals. The representative bioavailability-enhancing strategies are critically reviewed to provide practical solutions for augmenting the bioefficacy of GPP-rich botanicals. Synergistic applications of encapsulation techniques (for physiochemical protection and bypassing xenobiotic metabolism) and dietary intervention strategies involving modulation of gut microbiota (for generating more bioavailable phenolic metabolites) appear promising, and may substantially enhance the bioefficacy, especially the neuroprotective efficacy, of orally consumed GPPs.


Assuntos
Neuroproteção/efeitos dos fármacos , Polifenóis/química , Polifenóis/farmacologia , Vitis/química , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos
10.
J Food Drug Anal ; 27(3): 778-785, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31324293

RESUMO

Raspberry ketone (RK) is the characteristic aromatic compound in raspberry (Rubus idaeus L.) with wide applications as food additive and anti-obesity agent. However, quantification of RK has presented difficulties in MS detection and reliable LC-MS method for RK analysis in literature is in limit to date. In order to facilitate quality control of raspberry derived products and RK metabolomics study, this study aimed to develop a validated and sensitive UHPLC-MS/MS method. Strong in-source fragmentation was noted and the fragmental ion of 107 m/z produced was selected as the precursor ion for MRM detection, and as such the electrospray ionization performance was optimized by fractional factorial design to accommodate such ion-source dissociation behavior as well as its moderate volatility. A pathway involving the formation of quinone-like structure with strong conjugation was proposed to explain the intense in-source fragmentation. The MRM transition was optimized with product ion of 77 m/z selected as the quantifier ion. The method featured low limit of quantification of ∼2 ng/mL and allowed for rapid detection of RK in fresh raspberries following direct sample preparation. RK contents were found to be higher from locally grown and harvested farm sources compared to commercial products shipped into the state, and higher in those at late-stage compared with early-stage maturity. No correlations in RK content between organic and non-organic labels were noted.


Assuntos
Butanonas/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
11.
Nutr Res ; 68: 19-33, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31252376

RESUMO

Red raspberries (Rubus idaeus) contain numerous phenolic compounds with purported health benefits. Raspberry ketone (4-(4-hydroxyphenyl)-2-butanone) is a primary raspberry flavor phenolic found in raspberries and is designated as a synthetic flavoring agent by the Food and Drug Administration. Synthetic raspberry ketone has been demonstrated to result in weight loss in rodents. We tested whether phenolic-enriched raspberry extracts, compared with raspberry ketone, would be more resilient to the metabolic alterations caused by an obesogenic diet. Male C57BL/6J mice (8 weeks old) received a daily oral dose of vehicle (VEH; 50% propylene glycol, 40% water, and 10% dimethyl sulfoxide), raspberry extract low (REL; 0.2 g/kg), raspberry extract high (REH; 2 g/kg), or raspberry ketone (RK; 0.2 g/kg). Coincident with daily dosing, mice were placed on a high-fat diet (45% fat). After 4 weeks, REH and RK reduced body weight gain (approximately 5%-9%) and white adipose mass (approximately 20%) compared with VEH. Hepatic gene expression of heme oxygenase-1 and lipoprotein lipase was upregulated in REH compared with VEH. Indirect calorimetry indicated that respiratory exchange ratio (CO2 production to O2 consumption) was lower, suggesting increased fat oxidation with all treatments. REH treatment increased total ambulatory behavior. Energy expenditure/lean mass was higher in REH compared with REL treatment. There were no treatment differences in cumulative intake, meal patterns, or hypothalamic feed-related gene expression. Our results suggest that raspberry ketone and a phenolic-enriched raspberry extract both have the capacity to prevent weight gain but differ in the preventative mechanisms for excess fat accumulation following high-fat diet exposure.


Assuntos
Frutas/química , Heme Oxigenase-1/metabolismo , Lipase Lipoproteica/metabolismo , Fenóis/administração & dosagem , Rubus/química , Ganho de Peso/efeitos dos fármacos , Animais , Composição Corporal/efeitos dos fármacos , Butanonas/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Ingestão de Alimentos , Regulação da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/genética , Lipase Lipoproteica/genética , Fígado/enzimologia , Masculino , Camundongos , Consumo de Oxigênio/efeitos dos fármacos , Condicionamento Físico Animal , Extratos Vegetais/administração & dosagem
12.
Environ Toxicol Chem ; 38(7): 1585-1593, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30883883

RESUMO

Pharmaceuticals and personal care products (PPCPs) are emerging environmental contaminants that can be transformed by anaerobic microorganisms in anoxic environments. The present study examined 2 consortia, enriched under methanogenic and sulfate-rich conditions, that demethylate the phenylmethyl ether anti-inflammatory drug naproxen to 6-O-desmethylnaproxen. Both enriched consortia were also able to demethylate a range of phenylmethyl ether compounds of plant-based origin or used as PPCPs. Results from 16S rRNA gene sequencing showed that the 2 communities were very different despite sharing the same PPCP metabolism. In most cases, the demethylated metabolite was not further degraded but rather accumulated in the culture medium. For the expectorant guaifenesin, this resulted in a novel microbial metabolite. Furthermore, to our knowledge, this is the first report of methylparaben metabolism under methanogenic conditions. The wide range of phenylmethyl ether substrates that underwent O-demethylation in both methanogenic and sulfate-rich conditions suggests that there are potentially bioactive transformation products in the environment that have not yet been quantified. Environ Toxicol Chem 2019;38:1585-1593. © 2019 SETAC.


Assuntos
Cosméticos/metabolismo , Microbiota , Preparações Farmacêuticas/metabolismo , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Campylobacteraceae/genética , Campylobacteraceae/isolamento & purificação , Campylobacteraceae/metabolismo , Cosméticos/análise , Cosméticos/química , Cromatografia Gasosa-Espectrometria de Massas , Helicobacteraceae/genética , Helicobacteraceae/isolamento & purificação , Helicobacteraceae/metabolismo , Naproxeno/análogos & derivados , Naproxeno/análise , Naproxeno/metabolismo , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , RNA Ribossômico 16S/química , RNA Ribossômico 16S/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
13.
Sci Rep ; 9(1): 1524, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30728370

RESUMO

There is an increased need for improved and affordable insect repellents to reduce transmission of rapidly spreading diseases with high mortality rates. Natural products are often used when DEET cannot be afforded or accessed and when consumers choose not to use a synthetic repellent. The essential oils from two newly bred Nepeta cataria (catnip) plants representing two different chemotypes and their respective isolated nepetalactone isomers were evaluated as mosquito repellents against Aedes aegypti mosquitoes that transmit the Zika and Dengue virus in a one choice landing rate inhibition assay. A dose response curve was generated for each treatment and a time course analysis of repellency was performed over 24 hours with a N. cataria essential oil sample. The results indicate that all essential oil samples and their respective purified nepetalactone isomers were able to achieve greater than 95% repellency. Between two and four hours, the ability to repel more than 95% of the mosquitoes diminished. At the lowest concentrations tested, the nepetalactones and crude essential oil samples were more effective than DEET at reducing the number of mosquito landings.


Assuntos
Aedes/fisiologia , Monoterpenos Ciclopentânicos/farmacologia , Repelentes de Insetos/farmacologia , Nepeta/química , Óleos Voláteis/farmacologia , Óleos Vegetais/farmacologia , Pironas/farmacologia , Aedes/efeitos dos fármacos , Animais , Monoterpenos Ciclopentânicos/isolamento & purificação , Feminino , Repelentes de Insetos/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Óleos Vegetais/isolamento & purificação , Pironas/isolamento & purificação
14.
J Food Sci ; 84(2): 235-243, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30693503

RESUMO

Consumption safety of Solanum scabrum berries is controversial in different cultural practices and evaluation of the toxicity as well as micronutrition value relies on relevant phytochemical study. Thus, this study aimed to systematically profile the phytochemicals in the berries from different genetic sources and maturity. Using a combination of three different and complementary methods of HPLC-UV/Vis-MS or MS/MS with acid-assisted hydrolysis, a total of 54 phytochemicals were identified including polyphenols, saponins and toxic glycoalkaloids. Particularly, a broad range of glycoalkaloids of solasodine and its uncommon or potentially novel hydroxylated and methylated derivatives were reported, with the structure putatively identified based on the known scaffold-fragmentation pattern. Other identified phytochemicals included phenolic acids of chlorogenic acid and neochlorogenic acid, flavonol glycosides of quercetin and isorhamnetin, anthocyanins of petunidin, malvidin and delphinidin, and saponins of diosgenin and tigogenin. PRACTICAL APPLICATION: This study provides solutions for identifying the phytochemicals of S. scabrum berries, and unveiled for the first time a wide range of toxic glycoalkaloids of solasodine and analogues in the berries from different genetic sources and maturation stages. This work laid the foundation for prospective quantitative determination of berry phytochemicals and future toxicity and nutrition evaluation, and could also apply to facilitate screening or breeding for glycoalkaloid-deficient genotypes that can be used as new food supply.


Assuntos
Alcaloides/química , Polifenóis/química , Saponinas/química , Solanum/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Espectrofotometria Ultravioleta , Espectrometria de Massas em Tandem
15.
J Sci Food Agric ; 99(7): 3578-3587, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30628085

RESUMO

BACKGROUND: Solanum scabrum berries in sub-Saharan Africa are prolific but neglected as an agricultural resource. Recognition and application of such underutilized resources rely on systematic study of the relevant phytochemicals of commercial value. RESULTS: The quantities of a total of 54 phytochemicals in Solanum scabrum berries were assessed using HPLC-MS methods. Berries from eight different genetic sources were analyzed with two entries monitored across different maturation stages. There was a significant variation among mature berries in the accumulation of phenolic acids, 91.5-794 mg·100 g-1 dry weight (DW); flavonols, 76.3-897 mg·100 g-1 DW; anthocyanins, 178-4650 mg·100 g-1 DW; glycoalkaloids, 1.76-1630 mg·100 g-1 DW; and saponins, 82.2-606 mg·100 g-1 DW. Fruit development from immature to post-frost harvest featured dynamic changes in phytochemical composition and, despite remarkable differences in the absolute magnitude of content, the trend of change was generally similar in different genetic sources. CONCLUSIONS: The genotype-dependent difference in toxic glycoalkaloids in mature berries may partially explain the consumption controversy as it reflects glycoalkaloid content. The analytical methods applied in this work should serve for quality control of glycoalkaloids thereby improving the safe utilization of this berry. In addition, the selection and breeding of new genotypes with low and safe levels of glycoalkaloids and saponins in the berry could be of value in sub-Saharan Africa to increase nutrition and generate new income opportunities for growers. © 2019 Society of Chemical Industry.


Assuntos
Alcaloides/química , Extratos Vegetais/química , Polifenóis/química , Saponinas/química , Solanum/química , Cromatografia Líquida de Alta Pressão , Frutas/química , Espectrometria de Massas , Controle de Qualidade
16.
J Nutr Biochem ; 64: 170-181, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30530257

RESUMO

The intestinal microbiota actively converts dietary flavanols into phenolic acids, some of which are bioavailable in vivo and may promote resilience to select neurological disorders by interfering with key pathologic mechanisms. Since every person harbors a unique set of gut bacteria, we investigated the influence of the gut microbiota's interpersonal heterogeneity on the production and bioavailability of flavonoid metabolites that may interfere with the misfolding of alpha (α)-synuclein, a process that plays a central role in Parkinson's disease and other α-synucleinopathies. We generated two experimental groups of humanized gnotobiotic mice with compositionally diverse gut bacteria and orally treated the mice with a flavanol-rich preparation (FRP). The two gnotobiotic mouse groups exhibited distinct differences in the generation and bioavailability of FRP-derived microbial phenolic acid metabolites that have bioactivity towards interfering with α-synuclein misfolding or inflammation. We also demonstrated that these bioactive phenolic acids are effective in modulating the development and progression of motor dysfunction in a Drosophila model of α-synucleinopathy. Lastly, through in vitro bacterial fermentation studies, we identified select bacteria that are capable of supporting the generation of these bioavailable and bioactive phenolic acids. Outcomes from our studies provide a better understanding of how interpersonal heterogeneity in the gut microbiota differentially modulates the efficacy of dietary flavanols to protect against select pathologic mechanisms. Collectively, our findings provide the basis for future developments of probiotic, prebiotic, or synbiotic approaches for modulating the onset and/or progression of α-synucleinopathies and other neurological disorders involving protein misfolding and/or inflammation.


Assuntos
Microbioma Gastrointestinal/fisiologia , Polifenóis/farmacocinética , Sinucleinopatias/metabolismo , alfa-Sinucleína/metabolismo , alfa-Sinucleína/toxicidade , Animais , Animais Geneticamente Modificados , Disponibilidade Biológica , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Drosophila , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Polifenóis/metabolismo , Agregação Patológica de Proteínas/metabolismo , Dobramento de Proteína , Organismos Livres de Patógenos Específicos , Sinucleinopatias/patologia , alfa-Sinucleína/química , alfa-Sinucleína/genética
17.
J Pharm Biomed Anal ; 159: 374-383, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30032004

RESUMO

Grape-derived products contain a wide array of bioactive phenolic compounds which are of significant interest to consumers and researchers for their multiple health benefits. The majority of bioavailable grape polyphenols, including the most abundant flavan-3-ols, i.e. (+)-catechin and (-)-epicatechin, undergo extensive microbial metabolism in the gut, forming metabolites that can be highly bioavailable and bioactive. To gain a better understanding in microbial metabolism of grape polyphenols and to identify bioactive metabolites, advanced analytical methods are needed to accurately quantitate microbial-derived metabolites, particularly at trace levels, in addition to their precursors. This work describes the development and validation of a high-throughput, sensitive and reproducible GC-QqQ/MS method operated under MRM mode that allowed the identification and quantification of 16 phenolic acid metabolites, along with (+)-catechin and (-)-epicatechin, in flavanol-enriched broth samples anaerobically fermented with human intestinal bacteria. Excellent sensitivity was achieved with low limits of detection and low limits of quantification in the range of 0.24-6.18 ng/mL and 0.480-12.37 ng/mL, respectively. With the exception of hippuric acid, recoveries of most analytes were greater than 85%. The percent accuracies for almost all analytes were within ±23% and precision results were all below 18%. Application of the developed method to in vitro samples fermented with different human gut microbiota revealed distinct variations in the extent of flavanol catabolism, as well as production of bioactive phenolic acid metabolites. These results support that intestinal microbiota have a significant impact on the production of flavanol metabolites. The successful application of the established method demonstrates its applicability and robustness for analysis of grape flavanols and their microbial metabolites in biological samples.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidroxibenzoatos/metabolismo , Mucosa Intestinal/metabolismo , Polifenóis/análise , Polifenóis/metabolismo , Vitis/química , Disponibilidade Biológica , Catequina/análise , Humanos , Intestinos/microbiologia , Limite de Detecção , Microbiota
18.
BMC Plant Biol ; 18(1): 69, 2018 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-29685108

RESUMO

BACKGROUND: The basil (Ocimum spp.) genus maintains a rich diversity of phenotypes and aromatic volatiles through natural and artificial outcrossing. Characterization of population structure and genetic diversity among a representative sample of this genus is severely lacking. Absence of such information has slowed breeding efforts and the development of sweet basil (Ocimum basilicum L.) with resistance to the worldwide downy mildew epidemic, caused by the obligate oomycete Peronospora belbahrii. In an effort to improve classification of relationships 20 EST-SSR markers with species-level transferability were developed and used to resolve relationships among a diverse panel of 180 Ocimum spp. accessions with varying response to downy mildew. RESULTS: Results obtained from nested Bayesian model-based clustering, analysis of molecular variance and unweighted pair group method using arithmetic average (UPGMA) analyses were synergized to provide an updated phylogeny of the Ocimum genus. Three (major) and seven (sub) population (cluster) models were identified and well-supported (P < 0.001) by PhiPT (ΦPT) values of 0.433 and 0.344, respectively. Allelic frequency among clusters supported previously developed hypotheses of allopolyploid genome structure. Evidence of cryptic population structure was demonstrated for the k1 O. basilicum cluster suggesting prevalence of gene flow. UPGMA analysis provided best resolution for the 36-accession, DM resistant k3 cluster with consistently strong bootstrap support. Although the k3 cluster is a rich source of DM resistance introgression of resistance into the commercially important k1 accessions is impeded by reproductive barriers as demonstrated by multiple sterile F1 hybrids. The k2 cluster located between k1 and k3, represents a source of transferrable tolerance evidenced by fertile backcross progeny. The 90-accession k1 cluster was largely susceptible to downy mildew with accession 'MRI' representing the only source of DM resistance. CONCLUSIONS: High levels of genetic diversity support the observed phenotypic diversity among Ocimum spp. accessions. EST-SSRs provided a robust evaluation of molecular diversity and can be used for additional studies to increase resolution of genetic relationships in the Ocimum genus. Elucidation of population structure and genetic relationships among Ocimum spp. germplasm provide the foundation for improved DM resistance breeding strategies and more rapid response to future disease outbreaks.


Assuntos
Resistência à Doença/genética , Ocimum/genética , Peronospora , Doenças das Plantas/imunologia , Resistência à Doença/imunologia , Genes de Plantas/genética , Variação Genética/genética , Variação Genética/imunologia , Ocimum/imunologia , Ocimum basilicum/genética , Ocimum basilicum/imunologia , Filogenia , Filogeografia , Doenças das Plantas/microbiologia , Ploidias
19.
Chemosphere ; 202: 460-466, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29579680

RESUMO

While emerging pharmaceutical contaminants are monitored in wastewater treatment and the environment, there is little information concerning their microbial metabolites. The transformation of diphenhydramine by microorganisms in anaerobic digester sludge was investigated using anaerobic cultures amended with 1 mM diphenhydramine as the sole carbon source. Complete transformation of the parent compound to a persistent metabolite occurred within 191 days. Using GC/MS analysis, the metabolite was identified as N-desmethyl diphenhydramine. Loss of the parent compound diphenhydramine followed a first order rate constant of 0.013 day-1. There was no observed decrease in metabolite concentration even after a further 12 months of incubation, suggesting that the metabolite resists further degradation during wastewater treatment. Bacterial community diversity in the diphenhydramine transforming assay cultures showed enrichment in Comamonadaceae, Symbiobacteriaceae, Anaerolineaceae, and Prevotellaceae relative to unamended background controls. An anaerobic toxicity assay demonstrated that diphenhydramine has an inhibitory effect on both fermentative bacteria and methanogenic archaea in the wastewater community. In contrast, the metabolite N-desmethyl diphenhydramine partially suppressed methanogens but did not impact the fermenting community. To our knowledge, this is the first report of diphenhydramine metabolism by a bacterial community. The limited transformation of diphenhydramine by wastewater microorganisms indicates that N-desmethyl diphenhydramine will enter the environment along with unmetabolized diphenhydramine.


Assuntos
Difenidramina/metabolismo , Águas Residuárias/microbiologia , Anaerobiose , Bactérias/metabolismo , Desmetilação , Antagonistas dos Receptores Histamínicos/metabolismo , Esgotos/microbiologia
20.
J Food Drug Anal ; 26(2): 751-760, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29567246

RESUMO

African indigenous vegetables (AIVs) because of their nutrient density have the unique potential to reduce micronutrient deficiencies in sub-Saharan Africa, yet some may also contain anti-nutritive compounds. Vegetable nightshades from Solanum americanum, Solanum nigrum, Solanum scabrum and Solanum villosum are among the major AIVs used as a leafy vegetables and consumed regularly in many countries in sub-Sahara Africa. These under-recognized food crops have not been subjected to extensive studies for their nutritional and antinutritive factors. In this study, 15 entries of the vegetable nightshades were field-grown and the leaves which are the consumed product of commerce chemically profiled by LC/ESI-MS. Twenty-three flavones, eight saponins, and two glycoalkaloids along with a phenolic acid of chlorogenic acid were identified by MS and UV data. Anti-nutrient glycoalkaloids were quantified as total aglycones after acidic hydrolysis using MS detection and found to be within safe-consumption thresholds by comparison with the glycoalkaloid level in the globally consumed Solanum member eggplants. Edible nightshades were also found to be sources of ß-carotene, vitamin E and total polyphenols and exhibited high antioxidant activity. Results of this study support that consumption of vegetable nightshades are safe from the presence of glycoalkaloids and thus, can contribute to the reduction of micronutrient deficiency in sub-Sahara Africa.


Assuntos
Alcaloides/análise , Micronutrientes/análise , Extratos Vegetais/análise , Solanum/química , África ao Sul do Saara , Alcaloides/toxicidade , Antioxidantes/análise , Cromatografia Líquida , Folhas de Planta/química , Solanum/classificação , Espectrometria de Massas em Tandem , Verduras/química
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