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1.
Phys Rev Lett ; 133(5): 050203, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39159114

ABSTRACT

To address the outstanding task of detecting entanglement in large quantum systems, entanglement witnesses have emerged, addressing the separable nature of a state. Yet optimizing witnesses, or accessing them experimentally, often remains a challenge. We here introduce a family of entanglement witnesses for open quantum systems. Based on the electric field, it does not require state tomography or single-site addressing, but rather macroscopic measurements of the field quadratures and of the total fluorescence. Its efficiency is demonstrated by detecting, from almost any direction, the entanglement of collective single-photon states, such as long-lived states generated by cooperative spontaneous emission. Able to detect entanglement in large open quantum systems, and through a single continuous measurement if operating in the stationary regime, these electric-field-based witnesses can be used on any set of emitters described by the Pauli group, such as atomic systems (cold atoms and trapped ions), giant atoms, color centers, and superconducting qubits.

2.
J Nutr ; 154(4): 1232-1251, 2024 04.
Article in English | MEDLINE | ID: mdl-38346539

ABSTRACT

BACKGROUND: Complementary feeding is critical in establishing undernutrition. However, experimental undernourished diets do not represent the amount of nutrients in the complementary diets of undernourished children. OBJECTIVES: To develop, validate, and evaluate the impact of a new murine model of undernutrition on the intestinal epithelium, based on the complementary diet of undernourished children from 7 countries with low-socioeconomic power belonging to the Malnutrition-Enteric Diseases (MAL-ED) cohort study. METHODS: We used the difference in the percentage of energy, macronutrients, fiber and zinc in the complementary diet of children without undernutrition compared with stunting (height-for-age Z-score < -2) for the MAL-ED diet formulation. Subsequently, C57BL/6 mice were fed a control diet (AIN-93M diet) or MAL-ED diet for 28 d. Weight was measured daily; body composition was measured every 7 d; lactulose:mannitol ratio (LM) and morphometry were evaluated on days 7 and 28; the cotransport test and analysis of intestinal transporters and tight junctions were performed on day 7. RESULTS: The MAL-ED diet presented -8.03% energy, -37.46% protein, -24.20% lipid, -10.83% zinc, +5.93% carbohydrate, and +45.17% fiber compared with the control diet. This diet rapidly reduced weight gain and compromised body growth and energy reserves during the chronic period (P < 0.05). In the intestinal epithelial barrier, this diet caused an increase in the LM (P < 0.001) and reduced (P < 0.001) the villous area associated with an increase in FAT/CD36 in the acute period and increased (P < 0.001) mannitol excretion in the chronic period. CONCLUSIONS: The MAL-ED diet induced undernutrition in mice, resulting in acute damage to the integrity of the intestinal epithelial barrier and a subsequent increase in the intestinal area during the chronic period. This study introduces the first murine model of undernutrition for the complementary feeding phase, based on data from undernourished children in 7 different countries.


Subject(s)
Child Nutrition Disorders , Malnutrition , Humans , Infant , Child , Animals , Mice , Cohort Studies , Disease Models, Animal , Mice, Inbred C57BL , Malnutrition/complications , Infant Nutritional Physiological Phenomena , Child Nutrition Disorders/complications , Intestinal Mucosa/metabolism , Mannitol , Zinc
3.
Opt Lett ; 48(23): 6332-6335, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38039260

ABSTRACT

We propose a general scheme to generate entanglement encoded in the photon-number basis, via a sequential resonant two-photon excitation of a three-level system. We apply it to the specific case of a quantum dot three-level system, which can emit a photon pair through a biexciton-exciton cascade. The state generated in our scheme constitutes a tool for secure communication, as the multipartite correlations present in the produced state may provide an enhanced rate of secret communication with respect to a perfect GHZ state.

4.
Phys Rev Lett ; 130(5): 053601, 2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36800463

ABSTRACT

In this Letter, we show how to efficiently generate entanglement between two artificial giant atoms with photon-mediated interactions in a waveguide. Taking advantage of the adjustable decay processes of giant atoms into the waveguide and of the interference processes, spontaneous sudden birth of entanglement can be strongly enhanced with giant atoms. Highly entangled states can also be generated in the steady-state regime when the system is driven by a resonant classical field. We show that the statistics of the light emitted by the system can be used as a witness of the presence of entanglement in the system, since giant photon bunching is observed close to the regime of maximal entanglement. Given the degree of quantum correlations incoherently generated in this system, our results open a broad avenue for the generation of quantum correlations and manipulation of photon statistics in systems of giant atoms.

5.
Genet Mol Biol ; 46(4): e20230088, 2023.
Article in English | MEDLINE | ID: mdl-37992304

ABSTRACT

The tribe Serrasalmini is a diverse group with paraphyletic genera and taxonomic uncertainties. Several studies have been carried out in this group of fish in order to understand this problem, including the cytogenetic approach. In this study, three species of a clade of Serrasalmini were characterized cytogenetically - Pristobrycon striolatus, Catoprion absconditus and Pygopristis denticulatus. The three species presented diploid number (2n) equal to 62 chromosomes, of one and two arms, with karyotypic formulas and species-specific fundamental numbers. Heterochromatin is centromeric and terminal (bi-telomeric) in most chromosomes, with a conspicuous interstitial block at pair 1 (m) in all three species. The nucleolar organizer regions were multiple and C-band positive, and their location was confirmed via 18S ribosomal DNA mapping; however, with additional sites. The 5S rDNA was located in interstitial region of long arm of pair 1 (m), in the three species (homeologous). Moreover, we observed synteny between 18S and 5S in the species C. absconditus and P. denticulatus, which, according to fiber-FISH, are interspersed. Thus, the maintenance of 2n (62) evidences the diversification of chromosomal formulas within the clade by non-Robertsonian rearrangements and reflects the paraphyly of the related species.

6.
Phys Rev Lett ; 128(24): 240401, 2022 Jun 17.
Article in English | MEDLINE | ID: mdl-35776480

ABSTRACT

We propose a quantum Wheatstone bridge as a fully quantum analog to the classical version. The bridge is a few-body boundary-driven spin chain exploiting quantum effects to gain an enhanced sensitivity to an unknown coupling. The sensitivity is explained by a drop in population of an entangled Bell state due to destructive interference as the controllable coupling approaches the unknown coupling. A simple criterion for the destructive interference is found, and an approximate expression for the width of the drop is derived. The sensitivity to the unknown coupling is quantified using the quantum Fisher information, and we show that the state of the bridge can be measured indirectly through the spin current. Our results are robust toward calibration errors and generic in the sense that several of the current state-of-the-art quantum platforms could be used as a means of realization. The quantum Wheatstone bridge may thus find use in fields such as sensing and metrology using near-term quantum devices.

7.
Epidemiol Infect ; 149: e100, 2021 04 23.
Article in English | MEDLINE | ID: mdl-33888169

ABSTRACT

Brazil ranks second in the number of confirmed cases of COVID-19 worldwide. In spite of this, coping measures differ throughout the national territory, as does the disease's impact on the population. This cross-sectional observational study, with 59 695 cases of COVID-19 registered in the state of Alagoas between March and August 2020, analysed clinical-epidemiological variables, incidence rate, mortality rate, case fatality rate (CFR) and the social indicators municipal human development index (MHDI) and social vulnerability index (SVI). Moran statistics and regression models were applied. Logistic regression analysis was applied to determine the predictors of death. The incidence rate was 1788.7/100 000 inhabitants; mortality rate was 48.0/100 000 and CFR was 2.7%. The highest incidence rates were observed in municipalities with better human development (overall MHDI (I = 0.1668; p = 0.002), education MHDI (I = 0.1649; p = 0.002) and income MHDI (I = 0.1880; p = 0.005)) and higher social vulnerability (overall SVI (I = 0.0599; p = 0.033)). CFR was associated with higher social vulnerability (SVI human capital (I = 0.0858; p = 0.004) and SVI urban infrastructure (I = 0.0985; p = 0.040)). Of the analysed cases, 55.4% were female; 2/3 were Black or Brown and the median age was 41 years. Among deaths, most were male (919; 57.4%) and elderly (1171; 73.1%). The predictors of death were male sex, advanced age and the presence of comorbidities. In Alagoas, Brazil, the disease has undergone a process of interiorisation and caused more deaths in poorer municipalities. The presence of comorbidities and advanced age were predictors of death.


Subject(s)
COVID-19/epidemiology , Adult , Aged , Brazil/epidemiology , COVID-19/mortality , Cross-Sectional Studies , Databases, Factual , Female , Humans , Incidence , Logistic Models , Male , Middle Aged , Registries , Risk Factors , Spatial Analysis , Young Adult
8.
Phytochem Anal ; 30(1): 83-88, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30160074

ABSTRACT

INTRODUCTION: Kaurene diterpenes (KDs) constitute a chemical class often found in the genus Annona with interesting biological activities. To date, chromatographic tools have been mostly used to determine KDs. Quantitative nuclear magnetic resonance (qNMR) has distinguished itself in quantitative estimation of natural products and is an interesting choice to assess total KD contents. OBJECTIVE: To establish a 1 H qNMR method for determining the total KD contents in extracts and fractions obtained from Annona vepretorum stems. METHODOLOGY: Stems were extracted with hexane and methanol, resulting in the hexane extract (HEX-E) and the methanol extract (MeOH-E). The former was partitioned with the acid-base method to obtain the total alkaloid fraction (TA-F) and the neutral dichloromethane fraction (NDM-F). 1 H qNMR measurements were performed on 400 MHz with samples solubilized in deuterated dimethyl sulfoxide. Quantification was carried out using the signals at 4.71 and 4.78 ppm related to hydrogens of the exocyclic double bond of the basic skeleton of KDs and gallic acid as the standard reference. The selectivity, intra- and inter-day precision, reproducibility, limit of detection, limit of quantification, and robustness of the methodology were evaluated. RESULTS: Using the newly developed method, the total KD contents (in µg/mg) were 653.80 ± 12.15 (HEX-E), 458.90 ± 25.94 (NDM-F), 375.60 ± 27.52 (TA-F), and 315.10 ± 19.20 (MeOH-E). For determining the most promising bioactive sample, the KD contents and the sample discriminations obtained by principal component analysis were correlated to the antibacterial activity. Such approach pointed out HEX-E as a potential source of KDs. CONCLUSION: The developed method offers a fast and simple way of determining total KD contents.


Subject(s)
Annona/chemistry , Diterpenes, Kaurane/analysis , Diterpenes/analysis , Plant Extracts/chemistry , Plant Stems/chemistry , Proton Magnetic Resonance Spectroscopy/methods , Anti-Bacterial Agents/pharmacology , Limit of Detection , Microbial Sensitivity Tests , Principal Component Analysis , Reproducibility of Results
9.
Opt Lett ; 43(13): 3136-3139, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29957800

ABSTRACT

It is known that high intensity fields are usually required to implement shortcuts to adiabaticity via transitionless quantum driving (TQD). Here, we show that this requirement can be relaxed by exploiting the gauge freedom of generalized TQD, which is expressed in terms of an arbitrary phase when mimicking the adiabatic evolution. We experimentally investigate the performance of generalized TQD in comparison to both traditional TQD and adiabatic dynamics. By using a Yb+171 trapped ion hyperfine qubit, we implement a Landau-Zener adiabatic Hamiltonian and its (traditional and generalized) TQD counterparts. We show that the generalized theory provides energy-optimal Hamiltonians for TQD, with no additional fields required. In addition, the optimal TQD Hamiltonian for the Landau-Zener model is investigated under dephasing. Even using less intense fields, optimal TQD exhibits fidelities that are more robust against a decohering environment, with performance superior to that provided by the adiabatic dynamics.

10.
BMC Complement Altern Med ; 18(1): 284, 2018 Oct 19.
Article in English | MEDLINE | ID: mdl-30340567

ABSTRACT

BACKGROUND: Spondias tuberosa is a plant that produces a fruit crop with high economic relevance at Brazilian Caatinga. Its roots and leaves are used in folk medicine. METHODS: Chemical composition of a hexane extract from S. tuberosa leaves was evaluated by thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC) and 1H nuclear magnetic resonance (NMR). Antioxidant potential was investigated by DPPH and ABTS assays. Antifungal action on Candida species was evaluated determining the minimal inhibitory concentration (MIC50) and putative mechanisms were determined by flow cytometry analysis. In addition, hemolytic activity on human erythrocytes was assessed and the concentration required to promote 50% hemolysis (EC50) was determined. RESULTS: Phytochemical analysis by TLC showed the presence of flavonoids, hydrolysable tannins, saponins and terpenes. The HPLC profile of the extract suggested the presence of gallic acid (0.28 ± 0.01 g%) and hyperoside (1.27 ± 0.01 g%). The representative 1H NMR spectrum showed saturated and unsaturated fatty acids among the main components. The extract showed weak and moderate antioxidant activity in DPPH (IC50: 234.00 µg/mL) and ABTS (IC50: 123.33 µg/mL) assays, respectively. It was able to inhibit the growth of C. albicans and C. glabrata with MIC50 of 2.0 and 0.078 mg/mL, respectively. The treatment of C. glabrata cells with the extract increased levels of mitochondrial superoxide anion, caused hyperpolarization of mitochondrial membrane, and compromised the lysosomal membrane. Weak hemolytic activity (EC50: 740.8 µg/mL) was detected. CONCLUSION: The results demonstrate the pharmacological potential of the extract as antioxidant and antifungal agent, aggregating biotechnological value to this plant and stimulating its conservation.


Subject(s)
Anacardiaceae/chemistry , Antifungal Agents/pharmacology , Antioxidants/pharmacology , Mitochondrial Membranes/drug effects , Plant Extracts/pharmacology , Candida/cytology , Candida/drug effects , Hexanes , Lysosomes/drug effects
11.
Molecules ; 21(6)2016 Jun 11.
Article in English | MEDLINE | ID: mdl-27294907

ABSTRACT

From the aerial parts of Acmella ciliata (H.B.K.) Cassini (basionym Spilanthes ciliata Kunth; Asteraceae), three alkamides were isolated and identified by mass- and NMR spectroscopic methods as (2E,6E,8E)-N-isobutyl-2,6,8-decatrienamide (spilanthol, (1)), N-(2-phenethyl)-2E-en-6,8-nonadiynamide (2) and (2E,7Z)-6,9-endoperoxy-N-isobutyl-2,7-decadienamide (3). While 1 and 2 are known alkamides, compound 3 has not been described until now. It was found that the unusual cyclic peroxide 3 exists as a racemate of both enantiomers of each alkamide; the 6,9-cis- as well as the 6,9-trans-configured diastereomers, the former represents the major, the latter the minor constituent of the mixture. In vitro tests for activity against the human pathogenic parasites Trypanosoma brucei rhodesiense and Plasmodium falciparum revealed that 1 and 3 possess activity against the NF54 strain of the latter (IC50 values of 4.5 and 5.1 µM, respectively) while 2 was almost inactive. Compound 3 was also tested against multiresistant P. falciparum K1 and was found to be even more active against this parasite strain (IC50 = 2.1 µM) with considerable selectivity (IC50 against L6 rat skeletal myoblasts = 168 µM).


Subject(s)
Asteraceae/chemistry , Malaria/drug therapy , Plasmodium falciparum/drug effects , Polyunsaturated Alkamides/chemistry , Animals , Humans , Magnetic Resonance Spectroscopy , Malaria/parasitology , Plasmodium falciparum/pathogenicity , Polyunsaturated Alkamides/isolation & purification , Polyunsaturated Alkamides/pharmacology , Rats , Stereoisomerism , Trypanosoma brucei brucei/drug effects , Trypanosoma brucei brucei/pathogenicity
12.
Molecules ; 20(7): 11699-718, 2015 Jun 25.
Article in English | MEDLINE | ID: mdl-26121396

ABSTRACT

Remirea maritima is a tropical plant with a reticulated root system belonging to the family Cyperaceae, also known to have biologically active secondary metabolites. However, very few data on R. maritima's biological actions are available and there are no reports regarding the redox-active profile of this plant. In this study, we examined the total phenolic content of Remirea maritima hydroalcoholic (RMHA) extracts, redox properties against different reactive species generated in vitro and their cytotoxic effect against fibroblasts (L929) and melanoma (B16F10) cells. Total reactive antioxidant potential index (TRAP) and total antioxidant reactivity (TAR) results revealed that RMHA at all concentrations tested showed significant antioxidant capacity. RMHA was also effective against hydroxyl radical formation, reduction of Fe3+ to Fe2+ and in scavenging nitric oxide (NO) radicals. In vitro, the level of lipid peroxidation was reduced by RMHA extract and the data showed significant oxidative damage protection. The RMHA cytotoxicity was evaluated by a neutral red assay in fibroblast (L929) and melanome (B16F10) cells. The obtained results showed that the RMHA (40 and 80 µg/mL, respectively) reduced 70% of the viable cells. In conclusion, this study represents the first report regarding the antioxidant and anti-proliferative potential of R. maritima against B16F10 melanoma cells.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cyperaceae/chemistry , Fibroblasts/drug effects , Melanoma, Experimental/metabolism , Plant Extracts/pharmacology , Animals , Cell Line , Cell Line, Tumor , Fibroblasts/cytology , Fibroblasts/metabolism , Melanoma, Experimental/pathology , Mice , Oxidation-Reduction
13.
Inflammopharmacology ; 22(6): 351-65, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25168307

ABSTRACT

This study was conducted to explore the anti-inflammatory effect of Jungia sellowii (Asteraceae) using a murine model of pleurisy induced by carrageenan (Cg). This plant is used in southern Brazil to treat inflammatory diseases. J. sellowii leaves were extracted with ethanol/water to obtain the crude extract (CE), which was fractionated with different solvents, yielding n-hexane (Hex), dichloromethane (DCM), ethyl acetate (EtOAc) and n-butanol (BuOH) fractions, and aqueous fraction (Aq). The major compounds succinic acid (SA) and lactic acid (LA) were isolated from Aq fraction, and their structures were determined by (1)H and (13)C NMR. Pleurisy was induced by Cg (Saleh et al. 1996). The leukocytes, exudation, myeloperoxidase (MPO) and adenosine-deaminase (ADA) activities, metabolites of nitric oxide (NO x ) levels, protein levels and mRNA expression for interleukin 1 beta (IL-1ß), tumour necrosis factor alpha (TNF-α), interleukin 17A (IL17A) and inducible of nitric oxide synthase (iNOs), and p65 protein phosphorylation (NF-κB) were analysed 4 h after pleurisy induction. Animals pre-treated with CE, BuOH, Aq, SA, or LA inhibited leukocytes, exudation, MPO and ADA activities, NO x , IL-1ß, TNF-α, and IL-17A levels, and the mRNA expression for IL-1ß, TNF-α, IL-17A, iNOS, and p65 protein phosphorylation (NF-κB) (p < 0.05). Our study demonstrated that J. sellowii can protect against inflammation induced by Cg by decreasing the leukocytes and exudation. Its effects are related to the decrease of either proinflammatory cytokines and/or NO x . The isolated compounds SA and LA may play an important role in this anti-inflammatory action by inhibiting all the studied parameters. The anti-inflammatory properties of these compounds are due to the downregulation of NF-κB.


Subject(s)
Asteraceae/chemistry , Inflammation/drug therapy , Plant Extracts/pharmacology , Pleurisy/drug therapy , Animals , Anti-Inflammatory Agents/isolation & purification , Anti-Inflammatory Agents/pharmacology , Brazil , Carrageenan , Cytokines/metabolism , Disease Models, Animal , Female , Inflammation/pathology , Leukocytes/metabolism , Mice , Nitric Oxide/metabolism , Plant Leaves , Pleurisy/pathology , Solvents/chemistry
14.
Food Chem ; 448: 139047, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38520988

ABSTRACT

Dry-salted pirarucu (Arapaima gigas) plays an important cultural role in the Amazon region - South America. In this study, we explored the changes in the chemical composition of pirarucu meat following the drying-salting process via 1H NMR spectroscopy. Combining multivariate and univariate statistical analyses yielded a robust differentiation of metabolites involved in the process. VIP score (>1), p-value (<0.05), and AUC (>0.7) were considered to selecting compounds that had significant fluctuations in their contents along the process. Our results pointed out acetate, lactate, succinate, and creatinine as metabolites undergoing significant changes during the drying-salting process. Creatinine was not detected in fresh samples. The investigation of multiple components delves deeper into the molecular nuances of the salting-drying process's impact on fish meat, providing a more comprehensive understanding of the possible chemical transformations and how the matrix's quality control and nutritional aspects should be addressed.

15.
Sci Rep ; 14(1): 1758, 2024 01 19.
Article in English | MEDLINE | ID: mdl-38242927

ABSTRACT

Although some studies have shown neuroimaging and neuropsychological alterations in post-COVID-19 patients, fewer combined neuroimaging and neuropsychology evaluations of individuals who presented a mild acute infection. Here we investigated cognitive dysfunction and brain changes in a group of mildly infected individuals. We conducted a cross-sectional study of 97 consecutive subjects (median age of 41 years) without current or history of psychiatric symptoms (including anxiety and depression) after a mild infection, with a median of 79 days (and mean of 97 days) after diagnosis of COVID-19. We performed semi-structured interviews, neurological examinations, 3T-MRI scans, and neuropsychological assessments. For MRI analyses, we included a group of non-infected 77 controls. The MRI study included white matter (WM) investigation with diffusion tensor images (DTI) and functional connectivity with resting-state functional MRI (RS-fMRI). The patients reported memory loss (36%), fatigue (31%) and headache (29%). The quantitative analyses confirmed symptoms of fatigue (83% of participants), excessive somnolence (35%), impaired phonemic verbal fluency (21%), impaired verbal categorical fluency (13%) and impaired logical memory immediate recall (16%). The WM analyses with DTI revealed higher axial diffusivity values in post-infected patients compared to controls. Compared to controls, there were no significant differences in the functional connectivity of the posterior cingulum cortex. There were no significant correlations between neuropsychological scores and neuroimaging features (including DTI and RS-fMRI). Our results suggest persistent cognitive impairment and subtle white matter abnormalities in individuals mildly infected without anxiety or depression symptoms. The longitudinal analyses will clarify whether these alterations are temporary or permanent.


Subject(s)
Brain Diseases , COVID-19 , Cognitive Dysfunction , White Matter , Humans , Adult , Diffusion Tensor Imaging/methods , Cross-Sectional Studies , COVID-19/complications , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/etiology , Brain/diagnostic imaging , White Matter/diagnostic imaging , Memory Disorders , Fatigue/etiology
16.
Phys Rev E ; 108(6-1): 064106, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38243481

ABSTRACT

We investigate the effect of localization on the local charging of quantum batteries (QBs) modeled by disordered spin systems. Two distinct schemes based on the transverse-field random Ising model are considered, with Ising couplings defined on a Chimera graph and on a linear chain with up to next-to-nearest-neighbor interactions. By adopting a low-energy demanding charging process driven by local fields only, we obtain that the maximum extractable energy by unitary processes (ergotropy) is highly enhanced in the ergodic phase in comparison with the many-body localization (MBL) scenario. As we turn off the next-to-nearest-neighbor interactions in the Ising chain, we have the onset of the Anderson localization phase. We then show that the Anderson phase exhibits a hybrid behavior, interpolating between large and small ergotropy as the disorder strength is increased. We also consider the splitting of total ergotropy into its coherent and incoherent contributions. This incoherent part implies in a residual ergotropy that is fully robust against dephasing, which is a typical process leading to the self-discharging of the battery in a real setup. Our results are experimentally feasible in scalable systems, such as in superconducting integrated circuits.

17.
Food Res Int ; 164: 112441, 2023 02.
Article in English | MEDLINE | ID: mdl-36738006

ABSTRACT

The species of the genus Passiflora (Passifloraceae family) have been used as food, cosmetic and traditional herbal. As a result, the Passiflora species are widely cultivated and has an economic, medicinal and ornamental importance. The popular designation as "passion fruit" and chemical profile of several Passiflora species remains unknown. The lack of chemical information contributes to the erroneous classification and adulteration. In recent years, special attention has been paid to the bioactivity and phytochemical profiles of several Passiflora species extracts. In this research, 1H NMR-based metabolic profiling coupled with chemometric tools was used to characterize and distinguish extracts obtained from different wild Passiflora species (P. alata, P. cincinnata, and P. setacea) and genetic varieties (P. alata var. BRS Pérola do Cerrado, P. cincinnata var. BRS Sertão Forte, and P. setacea var. BRS Pérola do Cerrado). Fourteen metabolites were identified by 1D and 2D NMR experiments, highlighting the presence of fatty acids, carbohydrates, saponins, alkaloids, and mainly C-glycosidic flavones. Principal components analysis (PCA) allowed discrimination of Passiflora extracts, which the quadranguloside, oleanolic acid-3-sophoroside, α-glucose, ß-glucose, and vitexin-2-O"-rhamnoside were relevant in the differentiation of P. alata and P. alata var. BRS Pérola do Cerrado, while the flavones isovitexin and isovitexin-2-O"-xyloside were dominant in the grouping of P. setacea and P. setacea var. BRS Pérola do Cerrado, and finally P. cincinnata and P. cincinnata var. BRS Sertão Forte grouped by the influence of the fatty acids, sucrose, flavones (isoorientin and vitexin-2-O"-xyloside), and trigonelline. The varieties of P. setacea, and P. cincinnata are chemically equivalent to the original Passiflora species. However, the PCA analysis showed that the genetic variety of P. alata occupied a different position in the scores plot provoked mainly by the presence of oleanolic acid-3-sophoroside. The 1H NMR metabolic profile can be efficient for quality control evaluation, and can contribute to the investigation of new alternatives for official Passiflora herbal medicines.


Subject(s)
Flavones , Oleanolic Acid , Passiflora , Passiflora/genetics , Passiflora/chemistry , Chemometrics , Proton Magnetic Resonance Spectroscopy , Fatty Acids , Plant Extracts/chemistry , Metabolome , Glucose
18.
Food Chem ; 408: 135016, 2023 May 15.
Article in English | MEDLINE | ID: mdl-36525726

ABSTRACT

Green tea is a product obtained from the processing of fresh leaves of Camellia sinensis (L.) O. Kuntze species. In this study, the influence of climatic parameters on the chemical composition of green tea cultivars ('Yabukita' and 'Yutakamidori') over the harvest was evaluated using HR-MAS NMR. 'Yabukita' showed higher concentrations of epicatechin while higher amounts of theanine and caffeine were found in 'Yutakamidori'. The decline of theanine was associated with high average maximum temperature and solar radiation index, this latter also seemed to be responsible for relevant changes in epicatechin concentrations. It was not possible to associate any trend between climatic parameters and caffeine concentration. Fluctuations in linolenic acid concentration were monitored during the harvest period and were associated with the plant's defense mechanism. Monitoring of green tea over seasons and correlating the fluctuations of compounds to climatic parameters might become an efficient strategy for establishing quality standards for green teas.


Subject(s)
Camellia sinensis , Catechin , Tea/chemistry , Camellia sinensis/chemistry , Caffeine/analysis , Catechin/analysis , Chemometrics , Quality Control , Plant Leaves/chemistry
19.
Planta Med ; 78(14): 1601-6, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22814822

ABSTRACT

Plants are promising sources of new bioactive compounds. The aim of this study was to investigate the cytotoxic potential of nine plants found in Brazil. The species studied were: Annona pickelii Diels (Annonaceae), Annona salzmannii A. DC. (Annonaceae), Guatteria blepharophylla Mart. (Annonaceae), Guatteria hispida (R. E. Fr.) Erkens & Maas (Annonaceae), Hancornia speciosa Gomes (Apocynaceae), Jatropha curcas L. (Euphorbiaceae), Kielmeyera rugosa Choisy (Clusiaceae), Lippia gracilis Schauer (Verbenaceae), and Hyptis calida Mart. Ex Benth (Lamiaceae). Different types of extractions from several parts of plants resulted in 43 extracts. Their cytotoxicity was tested against HCT-8 (colon carcinoma), MDA-MB-435 (melanoma), SF-295 (glioblastoma), and HL-60 (promielocitic leukemia) human tumor cell lines, using the thiazolyl blue test (MTT) assay. The active extracts were those obtained from G. blepharophylla, G. hispida, J. curcas, K. rugosa, and L. gracilis. In addition, seven compounds isolated from the active extracts were tested; among them, ß-pinene found in G. hispida and one coumarin isolated from K. rugora showed weak cytotoxic activity. In summary, this manuscript contributes to the understanding of the potentialities of Brazilian plants as sources of new anticancer drugs.


Subject(s)
Bridged Bicyclo Compounds/pharmacology , Coumarins/pharmacology , Magnoliopsida/chemistry , Monoterpenes/pharmacology , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Annonaceae/chemistry , Antineoplastic Agents, Phytogenic , Apocynaceae/chemistry , Bicyclic Monoterpenes , Brazil , Bridged Bicyclo Compounds/chemistry , Bridged Bicyclo Compounds/isolation & purification , Cell Line, Tumor , Cell Survival , Clusiaceae/chemistry , Coumarins/chemistry , Coumarins/isolation & purification , Humans , Hyptis/chemistry , Jatropha/chemistry , Latex/chemistry , Lippia/chemistry , Monoterpenes/chemistry , Monoterpenes/isolation & purification , Oils, Volatile/chemistry , Oils, Volatile/isolation & purification , Plant Components, Aerial/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plants, Medicinal/chemistry
20.
Phys Rev E ; 105(5-1): 054115, 2022 May.
Article in English | MEDLINE | ID: mdl-35706233

ABSTRACT

One of the most important devices emerging from quantum technology are quantum batteries. However, self-discharging, the process of charge wasting of quantum batteries due to decoherence phenomenon, limits their performance, measured by the concept of ergotropy and half-life time of the quantum battery. The effects of local field fluctuation, introduced by the disorder term in the Hamiltonian of the system, on the performance of the quantum batteries is investigated in this paper. The results reveal that the disorder term could compensate disruptive effects of the decoherence, i.e., self-discharging, and hence improve the performance of the quantum battery via "incoherent gain of ergotropy" procedure. Adjusting the strength of the disorder parameter to a proper value and choosing a suitable initial state of the quantum battery, the amount of free ergotropy, defined with respect to the free Hamiltonian, could exceed the amount of initial stored ergotropy. In addition harnessing the degree of the disorder parameter could help to enhance the half-life time of the quantum battery. This study opens perspective to further investigation of the performance of quantum batteries that explore disorder and many-body effects.

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