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1.
Molecules ; 28(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37049978

RESUMO

Infrared spectroscopy (wavelengths ranging from 750-25,000 nm) offers a rapid means of assessing the chemical composition of a wide range of sample types, both for qualitative and quantitative analyses. Its use in the food industry has increased significantly over the past five decades and it is now an accepted analytical technique for the routine analysis of certain analytes. Furthermore, it is commonly used for routine screening and quality control purposes in numerous industry settings, albeit not typically for the analysis of bioactive compounds. Using the Scopus database, a systematic search of literature of the five years between 2016 and 2020 identified 45 studies using near-infrared and 17 studies using mid-infrared spectroscopy for the quantification of bioactive compounds in food products. The most common bioactive compounds assessed were polyphenols, anthocyanins, carotenoids and ascorbic acid. Numerous factors affect the accuracy of the developed model, including the analyte class and concentration, matrix type, instrument geometry, wavelength selection and spectral processing/pre-processing methods. Additionally, only a few studies were validated on independently sourced samples. Nevertheless, the results demonstrate some promise of infrared spectroscopy for the rapid estimation of a wide range of bioactive compounds in food matrices.


Assuntos
Antocianinas , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Espectrofotometria Infravermelho , Alimentos , Polifenóis
2.
Nature ; 532(7598): 223-7, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-27075099

RESUMO

Feedbacks between climate, erosion and tectonics influence the rates of chemical weathering reactions, which can consume atmospheric CO2 and modulate global climate. However, quantitative predictions for the coupling of these feedbacks are limited because the specific mechanisms by which climate controls erosion are poorly understood. Here we show that climate-dependent chemical weathering controls the erodibility of bedrock-floored rivers across a rainfall gradient on the Big Island of Hawai'i. Field data demonstrate that the physical strength of bedrock in streambeds varies with the degree of chemical weathering, which increases systematically with local rainfall rate. We find that incorporating the quantified relationships between local rainfall and erodibility into a commonly used river incision model is necessary to predict the rates and patterns of downcutting of these rivers. In contrast to using only precipitation-dependent river discharge to explain the climatic control of bedrock river incision, the mechanism of chemical weathering can explain strong coupling between local climate and river incision.

3.
Sensors (Basel) ; 22(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35062660

RESUMO

This paper examines the impact of ocean surface swell waves on near-coastal L-band high-resolution synthetic aperture radar (SAR) data collected using the National Aeronautics and Space Administration's (NASA) Soil Moisture Active/Passive (SMAP) radar at 40° incidence angle. The two-scale model and a more efficient off-nadir approximation of the second-order small-slope-approximation are used for co- and cross-polarized backscatter normalized radar cross-section (NRCS) predictions of the ocean surface, respectively. Backscatter NRCS predictions are modeled using a combined wind and swell model where wind-driven surface roughness is characterized using the Durden-Vesecky directional spectrum, while swell effects are represented through their contribution to the long wave slope variance (mean-square slopes, or MSS). The swell-only MSS is numerically computed based on a model defined using the JONSWAP spectrum with parameters calculated using the National Data Buoy Center and Wave Watch III data. The backscatter NRCS model is further refined to include fetch-limited and low-wind corrections. The results show an improved agreement between modeled and observed HH-polarized backscatter NRCS when swell effects are included and indicate a relatively larger swell impact on L-band compared to higher radar frequencies. Preliminary investigations into the potential swell retrieval capabilities in the form of excess MSS are encouraging, however further refinements are required to make broadly applicable conclusions.

4.
Phytother Res ; 35(7): 3484-3508, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33615599

RESUMO

Phenolic acid and flavonoid glycosides form a varied class of naturally occurring compounds, characterised by high polarity-resulting from the glycone moiety-and the presence of multiple phenol functionalities, which often leads to strong antioxidant activity. Phenolic glycosides, and in particular flavonoid glycosides, may possess strong bioactive properties with broad spectrum activity. This systematic literature review provides a detailed overview of 28 studies examining the biological activity of phenolic and flavonoid glycosides from plant sources, highlighting the potential of these compounds as therapeutic agents. The activity of glycosides depends upon the biological activity type, identity of the aglycone and the identity and specific location of the glycone moiety. From studies reporting the activity of both glycosides and their respective aglycones, phenolic glycosides appear to generally be a storage/reserve pool of precursors of more bioactive compounds. The glycosylated compounds are likely to be more bioavailable compared to their aglycone forms, due to the presence of the sugar moieties. Hydrolysis of the glycoside in the in vivo environment would release the free aglycone, potentiating their biological activity. However, further high-quality studies are needed to firmly establish the clinical efficacy of glycosides from many of the plant species studied.


Assuntos
Flavonoides , Glicosídeos , Fenóis , Plantas Medicinais/química , Flavonoides/farmacologia , Glicosídeos/farmacologia , Fenóis/farmacologia
5.
Molecules ; 26(15)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34361795

RESUMO

Although Australia is the largest exporter of faba bean globally, there is limited information available on the levels of bioactive compounds found in current commercial faba bean varieties grown in this country. This study profiled the phenolic acid and flavonoid composition of 10 Australian faba bean varieties, grown at two different locations. Phenolic profiling by HPLC-DAD revealed the most abundant flavonoid to be catechin, followed by rutin. For the phenolic acids, syringic acid was found in high concentrations (72.4-122.5 mg/kg), while protocatechuic, vanillic, p-hydroxybenzoic, chlorogenic, p-coumaric, and trans-ferulic acid were all found in low concentrations. The content of most individual phenolics varied significantly with the variety, while some effect of the growing location was also observed. This information could be used by food processors and plant breeders to maximise the potential health benefits of Australian-grown faba bean.


Assuntos
Antioxidantes/química , Produtos Agrícolas/química , Flavonoides/química , Vicia faba/química , Antioxidantes/classificação , Antioxidantes/isolamento & purificação , Austrália , Catequina/química , Catequina/isolamento & purificação , Ácido Clorogênico/química , Ácido Clorogênico/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Cumáricos/química , Ácidos Cumáricos/isolamento & purificação , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Flavonoides/classificação , Flavonoides/isolamento & purificação , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Humanos , Hidroxibenzoatos/química , Hidroxibenzoatos/isolamento & purificação , Parabenos/química , Parabenos/isolamento & purificação , Rutina/química , Rutina/isolamento & purificação , Ácido Vanílico/química , Ácido Vanílico/isolamento & purificação , Vicia faba/crescimento & desenvolvimento , Vicia faba/metabolismo
6.
J Card Surg ; 35(12): 3354-3361, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32996186

RESUMO

BACKGROUND: Valve-in-valve (ViV) transcatheter aortic valve replacement (TAVR) has become a valuable option in patients with bioprosthetic failure. However, potential issues with ViV TAVR may occur in patients with high-risk anatomy for coronary obstruction and patients with baseline smaller bioprosthetic valves at risk for patient prosthesis mismatch. The purpose of this study was, therefore, to use preoperative electrocardiography-gated, multidetector computed tomography (MDCT) in patients undergoing isolated surgical aortic valve replacement (SAVR) to (1) identify which would be high risk for coronary occlusion with ViV TAVR, and (2) predict intraoperative SAVR sizing. METHODS: Among 223 patients from our institutions' database that underwent SAVR for aortic insufficiency (AI) or aortic stenosis (AS) between January 2012 and January 2020, 48 patients had MDCT imaging before surgery (AI; n = 31, AS; n = 17). Of all patients, 67% (n = 32) were bicuspid morphology. RESULTS: With the use of virtual valve implantation, all patients with AI and bicuspid AS had feasible anatomy for ViV TAVR, while 38% of patients with tricuspid AS were high risk for coronary obstruction. There was a strong correlation between actual valve size implanted and preoperative MDCT measurements using annulus average diameter, area, and/or perimeter. CONCLUSION: Preoperative MDCT in patients undergoing SAVR is a useful tool for lifetime management, particularly in patients with tricuspid AS. Decisions for surgical management may change based on MDCT's ability to predict intraoperative SAVR size and determine which patients may be high-risk candidates for future ViV TAVR due to coronary artery obstruction.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Humanos , Tomografia Computadorizada Multidetectores , Resultado do Tratamento
7.
FASEB J ; 31(1): 109-119, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27671229

RESUMO

In an effort to inhibit the response to vascular injury that leads to intimal hyperplasia, this study investigated the in vivo efficacy of intraluminal delivery of thrombospondin-2 (TSP-2) small interfering RNA (siRNA). Common carotid artery (CCA) balloon angioplasty injury was performed in rats. Immediately after denudation, CCA was transfected intraluminally (15 min) with one of the following: polyethylenimine (PEI)+TSP-2 siRNA, saline, PEI only, or PEI+control siRNA. CCA was analyzed at 24 h or 21 d by using quantitative real-time PCR and immunohistochemistry. TSP-2 gene and protein expression were significantly up-regulated after endothelial denudation at 24 h and 21 d compared with contralateral untreated, nondenuded CCA. Treatment with PEI+TSP-2 siRNA significantly suppressed TSP-2 gene expression (3.1-fold) at 24 h and TSP-2 protein expression, cell proliferation, and collagen deposition up to 21 d. These changes could be attributed to changes in TGF-ß and matrix metalloproteinase-9, the downstream effectors of TSP-2. TSP-2 knockdown induced anti-inflammatory M2 macrophage polarization at 21 d; however, it did not significantly affect intima/media ratios. In summary, these data demonstrate effective siRNA transfection of the injured arterial wall and provide a clinically effective and translationally applicable therapeutic strategy that involves nonviral siRNA delivery to ameliorate the response to vascular injury.-Bodewes, T. C. F., Johnson, J. M., Auster, M., Huynh, C., Muralidharan, S., Contreras, M., LoGerfo, F. W., Pradhan-Nabzdyk, L. Intraluminal delivery of thrombospondin-2 small interfering RNA inhibits the vascular response to injury in a rat carotid balloon angioplasty model.


Assuntos
Angioplastia com Balão , Lesões das Artérias Carótidas/metabolismo , Regulação da Expressão Gênica/fisiologia , RNA Interferente Pequeno/administração & dosagem , Trombospondinas/metabolismo , Animais , Proliferação de Células , Colágeno , Macrófagos , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Ratos , Trombospondinas/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
8.
Ann Vasc Surg ; 49: 17-23, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29421418

RESUMO

BACKGROUND: The prevalence of obesity is increasing in the United States; however, its impact on adverse outcomes in patients with peripheral vascular disease is not well studied. Obesity is associated with higher rates of complications following open bypass surgery, but limited data are available on its effect on endovascular intervention. This study aimed to identify whether obese patients suffer the same complications when undergoing lower extremity endovascular interventions. METHODS: All patients who underwent femoropopliteal or tibial endovascular interventions between 2011 and 2013 were identified in the Targeted Vascular Module of the National Surgical Quality Improvement Program. Patients were stratified into 5 groups based on their body mass index (BMI): underweight (<18.6), normal weight (18.6-24.9), overweight (25-29.9), obese (30-34.9), and morbidly obese (≥35). Those patients without a documented BMI or a defined target lesion were excluded. Baseline demographics, patient characteristics, operative details, and outcomes were compared using univariate analysis between the BMI groups. Multivariable logistic regression was used to account for patient demographics and operative details. RESULTS: 3,246 patients underwent endovascular interventions (78% femoropopliteal and 22% tibial). Of these, 137 (4%) were underweight, 881 (27%) were normal weight, 1,193 (37%) were overweight, 647 (20%) were obese, and 388 (12%) were morbidly obese. There were no differences in 30-day mortality; however, surgical site infection (SSI) was higher in the morbidly obese (5% vs. normal weight: 2%, P = 0.02), whereas untreated patency loss was lower (morbidly obese: 0.5%, obese: 1%, normal weight: 2%, P = 0.02). Other important 30-day outcomes, including bleeding and amputation, were similar across the BMI groups. Following multivariate analysis, SSI remained more common in the morbidly obese (odds ratio [OR]: 2.6, 95% confidence interval [CI]: 1.4-5.0), whereas untreated patency loss remained lower in both overweight and morbidly obese patients (overweight: OR 0.5, 95% CI: 0.2-0.9 and morbidly obese: OR: 0.2, 95% CI: 0.05-0.85). Length of stay >1 day was significantly lower in the overweight, obese, and morbidly obese (OR 0.7, 95% CI: 0.6-0.8; OR 0.6, 95% CI: 0.5-0.7; and OR 0.7, 95% CI: 0.5-0.9, respectively). CONCLUSIONS: Few major complications occur in the obese in the first 30 days following endovascular interventions, and obesity is not an independent predictor of 30-day mortality. Rates of postoperative SSIs are low overall, although they are highest in morbidly obese patients (5%, compared to 2% in normal weight patients). Given this knowledge, endovascular interventions are a prudent treatment option for this patient population.


Assuntos
Procedimentos Endovasculares/efeitos adversos , Extremidade Inferior/irrigação sanguínea , Obesidade/epidemiologia , Doença Arterial Periférica/cirurgia , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Procedimentos Endovasculares/mortalidade , Feminino , Oclusão de Enxerto Vascular/epidemiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/diagnóstico , Obesidade/mortalidade , Razão de Chances , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/mortalidade , Doença Arterial Periférica/fisiopatologia , Prevalência , Fatores de Proteção , Fatores de Risco , Infecção da Ferida Cirúrgica/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia , Grau de Desobstrução Vascular
9.
J Opt Soc Am A Opt Image Sci Vis ; 34(3): 395-409, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28248366

RESUMO

A theoretical investigation of energy conservation, reflectivity, and emissivity in the scattering of electromagnetic waves from 3D multilayer media with random rough interfaces using the second-order small perturbation method (SPM2) is presented. The approach is based on the extinction theorem and develops integral equations for surface fields in the spectral domain. Using the SPM2, we calculate the scattered and transmitted coherent fields and incoherent fields. Reflected and transmitted powers are then found in the form of 2D integrations over wavenumber in the spectral domain. In the integrand, there is a summation over the spectral densities of each of the rough interfaces with each weighted by a corresponding kernel function. We show in this paper that there exists a "strong" condition of energy conservation in that the kernel functions multiplying the spectral density of each interface obey energy conservation exactly. This means that energy is conserved independent of the roughness spectral densities of the rough surfaces. Results of this strong condition are illustrated numerically for up to 50 rough interfaces without requiring specification of surface roughness properties. Two examples are illustrated. One is a multilayer configuration having weak contrasts between adjacent layers, random layer thicknesses, and randomly generated permittivity profiles. The second example is a photonic crystal of periodically alternating permittivities of larger dielectric contrast. The methodology is applied to study the effect of roughness on the brightness temperatures of the Antarctic ice sheet, which is characterized by layers of ice with permittivity fluctuations in addition to random rough interfaces. The results show that the influence of roughness can significantly increase horizontally polarized thermal emission while leaving vertically polarized emissions relatively unaffected.

10.
IEEE Trans Geosci Remote Sens ; Volume 55(Iss 4): 1897-1914, 2017 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31708601

RESUMO

This paper evaluates the retrieval of soil moisture in the top 5-cm layer at 3-km spatial resolution using L-band dual-copolarized Soil Moisture Active-Passive (SMAP) synthetic aperture radar (SAR) data that mapped the globe every three days from mid-April to early July, 2015. Surface soil moisture retrievals using radar observations have been challenging in the past due to complicating factors of surface roughness and vegetation scattering. Here, physically based forward models of radar scattering for individual vegetation types are inverted using a time-series approach to retrieve soil moisture while correcting for the effects of static roughness and dynamic vegetation. Compared with the past studies in homogeneous field scales, this paper performs a stringent test with the satellite data in the presence of terrain slope, subpixel heterogeneity, and vegetation growth. The retrieval process also addresses any deficiencies in the forward model by removing any time-averaged bias between model and observations and by adjusting the strength of vegetation contributions. The retrievals are assessed at 14 core validation sites representing a wide range of global soil and vegetation conditions over grass, pasture, shrub, woody savanna, corn, wheat, and soybean fields. The predictions of the forward models used agree with SMAP measurements to within 0.5 dB unbiased-root-mean-square error (ubRMSE) and -0.05 dB (bias) for both copolarizations. Soil moisture retrievals have an accuracy of 0.052 m3/m3 ubRMSE, -0.015 m3/m3 bias, and a correlation of 0.50, compared to in situ measurements, thus meeting the accuracy target of 0.06 m3/m3 ubRMSE. The successful retrieval demonstrates the feasibility of a physically based time series retrieval with L-band SAR data for characterizing soil moisture over diverse conditions of soil moisture, surface roughness, and vegetation.

11.
BMC Genomics ; 17: 20, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26728506

RESUMO

BACKGROUND: RNA interference (RNAi) is a powerful platform utilized to target transcription of specific genes and downregulate the protein product. To achieve effective silencing, RNAi is usually applied to cells or tissue with a transfection reagent to enhance entry into cells. A commonly used control is the same transfection reagent plus a "noncoding RNAi". However, this does not control for the genomic response to the transfection reagent alone or in combination with the noncoding RNAi. These control effects while not directly targeting the gene in question may influence expression of other genes that in turn alter expression of the target. The current study was prompted by our work focused on prevention of vascular bypass graft failure and our experience with gene silencing in human aortic smooth muscle cells (HAoSMCs) where we suspected that off target effects through this mechanism might be substantial. We have used Next Generation Sequencing (NGS) technology and bioinformatics analysis to examine the genomic response of HAoSMCs to the transfection reagent alone (polyethyleneimine (PEI)) or in combination with commercially obtained control small interfering RNA (siRNAs) (Dharmacon and Invitrogen). RESULTS: Compared to untreated cells, global gene expression of HAoSMcs after transfection either with PEI or in combination with control siRNAs displayed significant alterations in gene transcriptome after 24 h. HAoSMCs transfected by PEI alone revealed alterations of 213 genes mainly involved in inflammatory and immune responses. HAoSMCs transfected by PEI complexed with siRNA from either Dharmacon or Invitrogen showed substantial gene variation of 113 and 85 genes respectively. Transfection of cells with only PEI or with PEI and control siRNAs resulted in identification of 20 set of overlapping altered genes. Further, systems biology analysis revealed key master regulators in cells transfected with control siRNAs including the cytokine, Interleukin (IL)-1, transcription factor GATA Binding Protein (GATA)-4 and the methylation enzyme, Enhancer of zeste homolog 2 (EZH-2) a cytokine with an apical role in initiating the inflammatory response. CONCLUSIONS: Significant off-target effects in HAoSMCs transfected with PEI alone or in combination with control siRNAs may lead to misleading conclusions concerning the effectiveness of a targeted siRNA strategy. The lack of structural information about transfection reagents and "non coding" siRNA is a hindrance in the development of siRNA based therapeutics.


Assuntos
Aorta/efeitos dos fármacos , Biologia Computacional , Regulação da Expressão Gênica/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Aorta/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste , Fator de Transcrição GATA4/biossíntese , Regulação da Expressão Gênica/genética , Inativação Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Interleucina-1/biossíntese , Músculo Liso Vascular/metabolismo , Complexo Repressor Polycomb 2/biossíntese , Polietilenoimina/administração & dosagem , RNA Interferente Pequeno/genética , Transfecção/métodos
12.
Langmuir ; 31(38): 10402-10, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26352095

RESUMO

We analyze the rotational dynamics of spherical colloidal Janus particles made from silica (SiO2) with a hemispherical gold/palladium (Au/Pd) cap. Since the refractive index difference between the surrounding fluid and a two-faced, optically anisotropic Janus microsphere is a function of the particle's orientation, it is possible to observe its rotational dynamics with bright-field optical microscopy. We investigate rotational diffusion and constant rotation of single Janus microspheres which are partially tethered to a solid surface so they are free to rotate but show little or no translational motion. Also, since the metal cap is a powerful catalyst in the breakdown of hydrogen peroxide, H2O2, the particles can be activated chemically. In this case, we analyze the motion of coupled Janus dimers which undergo a stable rotary motion about a mutual center. The analysis of both experimental and simulation data, which are microscopy and computer-generated videos, respectively, is based upon individual particle tracking and differential dynamic microscopy (DDM). DDM, which typically requires ensemble averages to extract meaningful information for colloidal dynamics, can be effective in certain situations for systems consisting of single entities. In particular, when translational motion is suppressed, both rotational diffusion and constant rotation can be probed.


Assuntos
Ouro/química , Microesferas , Paládio/química , Rotação , Dióxido de Silício/química , Anisotropia , Coloides , Difusão , Peróxido de Hidrogênio/química , Microscopia , Tamanho da Partícula , Propriedades de Superfície
13.
Front Biosci (Elite Ed) ; 16(2): 16, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38939913

RESUMO

BACKGROUND: This study investigated the ultraviolet (UV) absorption spectra of various types and ages of grape wines and the correlation these spectra presented with their phenolic constituents. Firstly, the differences in UV spectra were characterized for different wine samples, depending on their type and age. METHODS: The following methods were used in this study: ultraviolet visible spectrophotometry, Folin-Ciocalteu spectrophotometric method, high-performance liquid chromatography. RESULTS: Then, it was demonstrated that for identically aged wines, the 280 nm absorbance is proportional to the concentration of phenolic compounds, as determined by the Folin-Ciocalteu method. Next, an investigation was conducted into the absorption coefficients of different phenolic classes commonly found in grapes and wine. Finally, the range in variation of phenolic compounds in various types of grape wines was established. CONCLUSIONS: This work provides a methodological approach to rapidly determine the concentration of phenolic compounds in wines using UV spectroscopy, provided that their age is known. As UV spectrophotometers are available in nearly all laboratories, this may provide a cheaper and faster alternative to current methods, including high-performance liquid chromatography (HPLC).


Assuntos
Fenóis , Espectrofotometria Ultravioleta , Vinho , Vinho/análise , Fenóis/análise , Fenóis/química , Cromatografia Líquida de Alta Pressão/métodos
14.
Plants (Basel) ; 13(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38592794

RESUMO

Sesame is an emerging crop of interest in Australia and has attracted widespread interest due to the health-benefitting properties of its bioactive compounds, including fatty acids, lignans, and polyphenols. This study aimed to investigate the impact of drought stress on these bioactive compounds, using eleven cultivars of black sesame seeds grown in Australia. Specific varieties responded positively to water deficit (WD) conditions, showing increased levels of TPC, FRAP, CUPRAC, and lignans. Varieties 1, 4, 7, and 12 showed significantly increased FRAP values ranging from 158.02 ± 10.43 to 195.22 ± 9.63 mg TE/100 g DW in the WD treatment compared to the well-watered (WW) treatment, whereas varieties 7, 10, 12, 13, and 18 demonstrated the highest CUPRAC values of all varieties (2584.86 ± 99.68-2969.56 ± 159.72 mg TE/100 g) across both WW and WD conditions, with no significant variations between irrigation regimes. Moreover, lignan contents (sesamin and sesamolin) were higher in varieties 1, 2, 5, and 8 grown in WD conditions. Compared to the optimal unsaturated to saturated fatty acid ratio (Σ UFA/Σ SFA ratio) of 0.45, all sesame genotypes showed superior ratios (ranging between 1.86 and 2.34). Moreover, the ω-6/ω-3 PUFA ratio varied from 33.7-65.5, with lower ratios in varieties 2, 4, 5, 8, and 18 under WD conditions. The high levels of phenolic compounds and healthy fats suggest the potential of black sesame to be incorporated into diets as a functional food. Furthermore, the enhanced phytochemistry of these cultivars in WD conditions is promising for widespread adoption. However, larger trial studies to confirm these findings across different geographic locations and seasons are warranted.

15.
Plants (Basel) ; 13(6)2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38592847

RESUMO

Bioprospecting native Australian plants offers the potential discovery of latent and novel bioactive compounds. The promising cytotoxic and antibacterial activity of methanolic extracts of Pittosporum angustifolium and Terminalia ferdinandiana led to further fractionation and isolation using our laboratory's bioassay-guided fractionation protocol. Hence, the aim of this study was to further evaluate the bioactivity of the fractions and subfractions and characterize bioactive compounds using liquid chromatography mass spectroscopy (LC-MS/MS) and gas chromatography MS (GC-MS). Compounds tentatively identified in P. angustifolium Fraction 1 using LC-ESI-QTOF-MS/MS were chlorogenic acid and/or neochlorogenic acid, bergapten, berberine, 8'-epitanegool and rosmarinic acid. GC-MS analysis data showed the presence of around 100 compounds, mainly comprising carboxylic acids, sugars, sugar alcohols, amino acids and monoalkylglycerols. Furthermore, the fractions obtained from T. ferdinandiana flesh extracts showed no cytotoxicity, except against HT29 cell lines, and only Fraction 2 exhibited some antibacterial activity. The reduced bioactivity observed in the T. ferdinandiana fractions could be attributed to the potential loss of synergy as compounds become separated within the fractions. As a result, the further fractionation and separation of compounds in these samples was not pursued. However, additional dose-dependent studies are warranted to validate the bioactivity of T. ferdinandiana flesh fractions, particularly since this is an understudied species. Moreover, LC-MS/GC-MS studies confirm the presence of bioactive compounds in P. angustifolium Fraction 1/subfractions, which helps to explain the significant acute anticancer activity of this plant. The screening process designed in this study has the potential to pave the way for developing scientifically validated phytochemical/bioactivity information on ethnomedicinal plants, thereby facilitating further bioprospecting efforts and supporting the discovery of novel drugs in modern medicine.

16.
Foods ; 12(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36981072

RESUMO

Foxtail millet husk (FMH) is generally removed and discarded during the first step of millet processing. This study aimed to optimize a method using deep eutectic solvents (DESs) combined with ultrasonic-assisted extraction (UAE) to extract phenols from FMH and to identify the phenolic compositions and evaluate the biological activities. The optimized DES comprised L-lactic acid and glycol with a 1:2 molar ratio by taking the total flavonoid content (TFC) and total phenolic content (TPC) as targets. The extraction parameters were optimized to maximize TFC and TPC, using the following settings: liquid-to-solid ratio of 25 mL/g, DES with water content of 15%, extraction time of 41 min and temperature of 51 °C, and ultrasonic power at 304 W. The optimized UAE-DES, which produced significantly higher TPC, TFC, antioxidant activity, α-glucosidase, and acetylcholinesterase inhibitory activities compared to conventional solvent extraction. Through UPLC-MS, 12 phenolic compounds were identified, with 1-O-p-coumaroylglycerol, apigenin-C-pentosyl-C-hexoside, and 1-O-feruloyl-3-O-p-coumaroylglycerol being the main phenolic components. 1-O-feruloyl-3-O-p-coumaroylglycerol and 3,7-dimethylquercetin were identified first in foxtail millet. Our results indicated that FMH could be exploited by UAE-DES extraction as a useful source of naturally derived antioxidants, along with acetylcholinesterase and α-glucosidase inhibitory activities.

17.
J AOAC Int ; 106(4): 1070-1076, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-36367248

RESUMO

BACKGROUND: Recent technological progress has bolstered efforts to bring personalized medicine from theory into clinical practice. However, progress in areas such as therapeutic drug monitoring (TDM) has remained somewhat stagnant. In drugs with well-known dose-response relationships, TDM can enhance patient outcomes and reduce health care costs. Traditional monitoring methods such as chromatography-based or immunoassay techniques are limited by their higher costs and slow turnaround times, making them unsuitable for real-time or onsite analysis. OBJECTIVE: In this work, we propose the use of a fast, direct, and simple approach using Fourier transform infrared spectroscopy (FT-IR) combined with chemometric techniques for the therapeutic monitoring of valproic acid (VPA). METHOD: In this context, a database of FT-IR spectra was constructed from human plasma samples containing various concentrations of VPA; these samples were characterized by the reference method (immunoassay technique) to determine the VPA contents. The FT-IR spectra were processed by two chemometric regression methods: partial least-squares regression (PLS) and support vector regression (SVR). RESULTS: The results provide good evidence for the effectiveness of the combination of FT-IR spectroscopy and SVR modeling for estimating VPA in human plasma. SVR models showed better predictive abilities than PLS models in terms of root-mean-square error of calibration and prediction RMSEC, RMSEP, R2Cal, R2Pred, and residual predictive deviation (RPD). CONCLUSIONS: This analytical tool offers potential for real-time TDM in the clinical setting. HIGHLIGHTS: FTIR spectroscopy was evaluated for the first time to predict VPA in human plasma for TDM. Two regressions were evaluated to predict VPA in human plasma, and the best-performing model was obtained using nonlinear SVR.


Assuntos
Monitoramento de Medicamentos , Ácido Valproico , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise dos Mínimos Quadrados , Calibragem
18.
Metabolites ; 13(10)2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37887387

RESUMO

Adzuki bean has recently been proposed as a viable dual-purpose (grain-and-graze) crop for the Northern regions of Australia because of its successful use in semi-arid regions and its nitrogen fixation capacity to improve soil fertility and animal nutrition. However, there are very few studies on the phytochemical composition and nutritional value of the non-seed material. This study investigated the phenolic composition of the parts grown in the vegetative phase (leaves and stems) of nine Australian adzuki bean varieties for the first time. The total phenolic content (TPC) of the stem material (157-406 mg GAE/100 g) was 23-217% higher than that of commercial livestock feed, while the TPC of the leaf material (1158-1420 mg GAE/100 g) was 9-11 times higher. Using tandem liquid chromatography mass spectrometry (LC-MS), the major phenolic compounds identified were rutin, luteolin, salicylic acid, and quercetin-3-glucoside. The leaf and stem materials showed high levels of apparent in vitro dry matter digestibility, with no significant difference in total gas or methane production compared to lucerne hay. The results suggest that adzuki bean vegetative materials could be a high-value livestock fodder and support pursuing further in-depth studies into their nutritional value for livestock.

19.
Nat Commun ; 14(1): 5427, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37696798

RESUMO

Hadal trenches are unique geological and ecological systems located along subduction zones. Earthquake-triggered turbidites act as efficient transport pathways of organic carbon (OC), yet remineralization and transformation of OC in these systems are not comprehensively understood. Here we measure concentrations and stable- and radiocarbon isotope signatures of dissolved organic and inorganic carbon (DOC, DIC) in the subsurface sediment interstitial water along the Japan Trench axis collected during the IODP Expedition 386. We find accumulation and aging of DOC and DIC in the subsurface sediments, which we interpret as enhanced production of labile dissolved carbon owing to earthquake-triggered turbidites, which supports intensive microbial methanogenesis in the trench sediments. The residual dissolved carbon accumulates in deep subsurface sediments and may continue to fuel the deep biosphere. Tectonic events can therefore enhance carbon accumulation and stimulate carbon transformation in plate convergent trench systems, which may accelerate carbon export into the subduction zones.

20.
Foods ; 11(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35267285

RESUMO

Ginger is best known for its aromatic odour, spicy flavour and health-benefiting properties. Its flavour is derived primarily from two compound classes (gingerols and shogaols), with the overall quality of the product depending on the interaction between these compounds. Consequently, a robust method for determining the ratio of these compounds would be beneficial for quality control purposes. This study investigated the feasibility of using hyperspectral imaging to rapidly determine the ratio of 6-gingerol to 6-shogoal in dried ginger powder. Furthermore, the performance of several pre-processing methods and two multivariate models was explored. The best-performing models used partial least squares regression (PSLR) and least absolute shrinkage and selection operator (LASSO), using multiplicative scatter correction (MSC) and second derivative Savitzky-Golay (2D-SG) pre-processing. Using the full range of wavelengths (~400-1000 nm), the performance was similar for PLSR (R2 ≥ 0.73, RMSE ≤ 0.29, and RPD ≥ 1.92) and LASSO models (R2 ≥ 0.73, RMSE ≤ 0.29, and RPD ≥ 1.94). These results suggest that hyperspectral imaging combined with chemometric modelling may potentially be used as a rapid, non-destructive method for the prediction of gingerol-to-shogaol ratios in powdered ginger samples.

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