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1.
Matern Child Nutr ; 19(3): e13495, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37002659

RESUMO

Context-specific research is needed on the relationship between household animal production and nutrition outcomes to inform programmes intervening in small-scale animal production. We examined associations between household animal/fishpond ownership and animal source food (ASF) consumption among 6- to 12-month-old infants enroled in the control arm of a cluster-randomised controlled trial in rural Bangladesh. We measured ASF consumption using a 7-day food frequency questionnaire at 6, 9 and 12 months and assessed household animal/fishpond ownership at 12 months. We developed negative binomial regression models with random intercepts for infant and cluster, controlling for infant age and sex, maternal age, socioeconomic status and season. Models were stratified by a dichotomised maternal decision-making score. Compared with infants in households without each animal type, those with 4-10 and ≥11 poultry consumed eggs 1.3 (95% confidence interval [CI]: 1.1, 1.6) and 1.6 (95% CI: 1.3, 2.0) times more, respectively; 2-3 and ≥4 dairy-producing animals consumed dairy 1.9 (95% CI: 1.3, 2.7) and 2.0 (95% CI: 1.3, 3.1) times more, respectively; and ≥12 meat-producing animals consumed meat 1.4 (95% CI: 1.0, 1.8) times more. It was unclear whether there was an association between fishpond ownership and fish consumption. Our results did not suggest that maternal decision-making power was a modifier in the relationship between animal/fishpond ownership and ASF consumption. In this South Asian context, strategies intervening in household animal production may increase infant consumption of eggs, dairy and meat, but not necessarily fish. Research is needed on the role of market access and other dimensions of women's empowerment.


Assuntos
Carne , Propriedade , Animais , Humanos , Feminino , Bangladesh , Ovos , Características da Família , População Rural
2.
New Phytol ; 227(1): 132-145, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32129887

RESUMO

Photosynthetic stimulation by elevated [CO2 ] (e[CO2 ]) may be limited by the capacity of sink organs to use photosynthates. In many legumes, N2 -fixing symbionts in root nodules provide an additional sink, so that legumes may be better able to profit from e[CO2 ]. However, drought not only constrains photosynthesis but also the size and activity of sinks, and little is known about the interaction of e[CO2 ] and drought on carbon sink strength of nodules and other organs. To compare carbon sink strength, faba bean was grown under ambient (400 ppm) or elevated (700 ppm) atmospheric [CO2 ] and subjected to well-watered or drought treatments, and then exposed to 13 C pulse-labelling using custom-built chambers to track the fate of new photosynthates. Drought decreased 13 C uptake and nodule sink strength, and this effect was even greater under e[CO2 ], and was associated with an accumulation of amino acids in nodules. This resulted in decreased N2 fixation, and increased accumulation of new photosynthates (13 C/sugars) in leaves, which in turn can feed back on photosynthesis. Our study suggests that nodule C sink activity is key to avoid sink limitation in legumes under e[CO2 ], and legumes may only be able to achieve greater C gain if nodule activity is maintained.


Assuntos
Vicia faba , Dióxido de Carbono , Sequestro de Carbono , Fotossíntese , Abastecimento de Água
3.
Plant Cell Environ ; 41(10): 2418-2434, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29859018

RESUMO

Increased biomass and yield of plants grown under elevated [CO2 ] often corresponds to decreased grain N concentration ([N]), diminishing nutritional quality of crops. Legumes through their symbiotic N2 fixation may be better able to maintain biomass [N] and grain [N] under elevated [CO2 ], provided N2 fixation is stimulated by elevated [CO2 ] in line with growth and yield. In Mediterranean-type agroecosystems, N2 fixation may be impaired by drought, and it is unclear whether elevated [CO2 ] stimulation of N2 fixation can overcome this impact in dry years. To address this question, we grew lentil under two [CO2 ] (ambient ~400 ppm and elevated ~550 ppm) levels in a free-air CO2 enrichment facility over two growing seasons sharply contrasting in rainfall. Elevated [CO2 ] stimulated N2 fixation through greater nodule number (+27%), mass (+18%), and specific fixation activity (+17%), and this stimulation was greater in the high than in the low rainfall/dry season. Elevated [CO2 ] depressed grain [N] (-4%) in the dry season. In contrast, grain [N] increased (+3%) in the high rainfall season under elevated [CO2 ], as a consequence of greater post-flowering N2 fixation. Our results suggest that the benefit for N2 fixation from elevated [CO2 ] is high as long as there is enough soil water to continue N2 fixation during grain filling.


Assuntos
Dióxido de Carbono/metabolismo , Lens (Planta)/metabolismo , Fixação de Nitrogênio , Biomassa , Produção Agrícola , Desidratação , Lens (Planta)/crescimento & desenvolvimento , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Nodulação , Água/metabolismo
5.
BMC Complement Altern Med ; 13: 101, 2013 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-23663985

RESUMO

BACKGROUND: Caesalpinia bonducella is an important medicinal plant for its traditional uses against different types of diseases. Therefore, the present study investigated the antimicrobial, antidiarrhoeal, and cytotoxic activities of the methanol extract and ethyl acetate, chloroform, and petroleum ether (pet. ether) fractions of C. bonducella leaves. METHODS: The antibacterial potentialities of methanol extract and its fractions of C. bonducella leaves were investigated by the disc diffusion method against four gram-positive and five gram-negative bacteria at 300, 500 and 800 µg/disc. Kanamycin (30 µg/disc) was used as the standard drug. Antidiarrhoeal activities of leaf extracts were evaluated at two doses (200 and 400 mg/kg) and compared with loperamide in a castor oil-induced diarrhoeal model in rat. The fractions were subjected to a brine shrimp lethality test to evaluate their cytotoxicity. RESULTS: The methanol extract and other three fractions exhibited better activities at higher concentrations. Amongst, the chloroform fraction showed maximum activity at all three concentrations (300, 500, and 800 µg/disc) against almost all bacteria. S. aureus and P. aeruginosa showed better sensitivities to all extracts at all three concentrations excluding the pet. ether fraction. Bacillus megaterium and Klebsiella spp. were two bacteria amongst nine that showed lowest sensitivity to the extracts. Maximum zone of inhibition (25-mm) was obtained by the methanol extract at an 800 µg/disc concentration against S. aureus. In the antidiarrhoeal test, all fractions exhibited dose-dependent actions, which were statistically significant (p < 0.05). Ethyl acetate fraction exerted maximum inhibition (51.11%) against defecation, whereas 57.75% inhibition was obtained for loperamide. Moderate cytotoxicity was found for the methanol extract and its three fractions compared with the standard drug vincristine sulfate in the brine shrimp bioassay. In the present study, the LC50 values of the methanol crude extract and ethyl acetate, chloroform, pet. ether fractions and vincristine sulfate were 223.87, 281.84, 112.2, 199.53, and 12.59 µg/mL, respectively. Therefore, the ethyl acetate fraction showed maximum cytotoxicity, whereas minimum cytotoxicity was observed for the chloroform fraction. CONCLUSION: The present study revealed that the ethyl acetate fraction of the C. bonducella leaves has significant antidiarrhoeal properties. The methanol extract and other three fractions of the C. bonducella leaves possess potent antibacterial activities along with moderate cytotoxicities that may lead to new drug development.


Assuntos
Antibacterianos/farmacologia , Antidiarreicos/uso terapêutico , Bactérias/efeitos dos fármacos , Caesalpinia , Diarreia/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Antidiarreicos/farmacologia , Artemia/efeitos dos fármacos , Defecação/efeitos dos fármacos , Diarreia/induzido quimicamente , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Loperamida/farmacologia , Loperamida/uso terapêutico , Masculino , Extratos Vegetais/farmacologia , Folhas de Planta/efeitos dos fármacos , Ratos , Ratos Long-Evans
6.
PLoS One ; 17(6): e0270102, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35731829

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common female reproductive endocrine problem worldwide. The prevalence of mental disorder is increasing among PCOS patients due to various physical, psychological, and social issues. Here we aimed to evaluate the mental health and associated factors among women suffering from PCOS in Bangladesh. METHODS: We performed an online cross-sectional survey among 409 participants with PCOS using Google Forms. We used structured questionnaires to collect socio-demographic information and lifestyle-related factors. Also, we applied patient health questionnaire (PHQ-9), generalized anxiety disorder (GAD-7) scale, and UCLA loneliness (UCLA-3) scale for psychometric assessment of the participants. Finally, we applied several statistical tools and performed data interpretations to evaluate the prevalence of mental health disorders and associated factors among patients with PCOS in Bangladesh. RESULTS: Prevalence of loneliness, generalized anxiety disorder and depressive illness among the women with PCOS were 71%, 88%, and 60%, respectively. Among the mental illness, mild, moderate, and severe cases were 39%, 18%, and 14% for loneliness; 39%, 23% and 26% for generalized anxiety disorder; and 35%, 18%, and 7% for depressive disorder. According to the present findings, obesity, financial condition, physical exercise, mealtime, food habit, daily water consumption, birth control method, and long-term oral contraceptive pills contribute to developing mental health disorders among females with PCOS in Bangladesh. CONCLUSION: According to present study results, high proportion of women suffering from PCOS experience several mental disorders in Bangladesh. Although several socio-demographic and lifestyle-related factors were found to be associated with the poor mental health of women with PCOS; however, PCOS itself is a condition that favors poor physical and psychological health. Therefore, we recommend proper treatment, public awareness, and a healthy lifestyle to promote the good mental health of women suffering from PCOS.


Assuntos
Síndrome do Ovário Policístico , Bangladesh/epidemiologia , Estudos Transversais , Feminino , Humanos , Saúde Mental , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/epidemiologia , Prevalência , Fatores de Risco
7.
Women Birth ; 34(1): e76-e83, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32651153

RESUMO

BACKGROUND: In order to promote sustainable midwifery education, it is important to understand what the structural shortcomings are. In this study of 38 public nursing institutions in Bangladesh, we aim to identify a number of structural shortcomings and to discuss strategies for limiting them. METHODS: An evaluated context-specific accreditation assessment tool consisting of 37 multi-choice closed-response questions encompassing 14 educational standards aligned with international standards for midwifery education programs and competences for midwifery educators was used to assess all public nursing institutions in Bangladesh (n=38), the results of which are presented in simple descriptive statistics; number (n), percentage (%), mean, SD and minimum-maximum value. RESULTS: Provision around clinical practice sites is the key structural shortcoming within the Bangladeshi midwifery educational system. Twenty-five percent of the institutions provided no opportunity for midwifery students to practice comprehensive sexual and reproductive health care. Twenty-nine per cent of the clinical sites were not aware of the content of midwifery courses and syllabi. Finally, one third of students achieving a midwifery qualification did not meet the learning outcomes to support women in birth. CONCLUSIONS: To measure progress towards national and global milestones to ensure students are equipped with required competencies before graduating as registered midwives will be difficult to meet unless shortcomings within the educational system are addressed. We recommend (i) the inclusion of clinical placement sites in future assessments, (ii) the introduction of an integrated feedback-appeal-response system, and (iii) the development of a system for improved communication links between educational institutions and clinical placement sites.


Assuntos
Acreditação , Currículo/normas , Bacharelado em Enfermagem/normas , Tocologia/educação , Enfermeiros Obstétricos/educação , Adulto , Bangladesh , Competência Clínica/normas , Feminino , Humanos , Gravidez , Garantia da Qualidade dos Cuidados de Saúde , Estudantes de Enfermagem , Adulto Jovem
8.
J Trop Med ; 2021: 7239291, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659421

RESUMO

BACKGROUND: The leaves of Leea rubra contain an abundance of phenolic constituents and have medicinal uses as antipyretic and diaphoretic agents and are also used in the treatment of stomach ache, rheumatism, arthritis etc. In spite of the traditional uses, data on the scientific evaluation of the plant are not sufficient. So, the present study was designed to evaluate the protective role of the extract against oxidative damage to DNA and human erythrocytes as well as antitumor and antibacterial activities against some resistant bacteria. METHODS: The protective activity of the ethyl acetate fraction (EAF) of the extract was investigated by evaluating the inhibition of oxidative damage of pUC19 plasmid DNA as well as hemolysis and lipid peroxidation damage to human erythrocytes induced by 2,2'-azobis-2-amidinopropane (AAPH). Antitumor activity was assessed by evaluating the percentage inhibition of cell growth, morphological changes of Ehrlich's ascites carcinoma (EAC) cells, and hematological parameters. Antimicrobial activity was determined by the disc diffusion method against different resistant microorganisms. RESULTS: EAF effectively inhibited AAPH-induced oxidative damage to DNA because it can inhibit the transformation of the supercoiled form of plasmid DNA to open circular and further linear form. The oxidative hemolysis caused by AAPH in human erythrocytes was inhibited by EAF extract in a time-dependent manner, and the production of malondialdehyde (MDA) was significantly reduced, which indicates the prevention of lipid peroxidation. In antitumor assay, 76% growth of inhibition of EAC was observed compared with the control mice (p < 0.05) at a dose of 100 mg/kg body weight. Antimicrobial activity was evaluated against two pathogenic resistant microorganisms (Escherichia coli and Pseudomonas aeruginosa), and the highest antimicrobial activity was observed against Pseudomonas spp. CONCLUSION: EAF may have great importance in preventing oxidative damage to DNA, erythrocytes, and other cellular components as well as can be a good candidate in cancer chemotherapy and treating infectious diseases caused by antibiotic-resistant bacteria.

9.
J Plant Physiol ; 229: 164-169, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30103086

RESUMO

The 'CO2 fertilisation effect' is often predicted to be greater under drier than wetter conditions, mainly due to hypothesised early season water savings under elevated [CO2] (e[CO2]). However, water savings largely depend on the balance between CO2-induced improvement of leaf-level water use efficiency and CO2-stimulation of transpiring leaf area. The dynamics of water use during the growing season can therefore vary depending on leaf area development. Two canola (Brassica napus L.) cultivars of contrasting growth and vigour (vigorous hybrid cv. Hyola 50 and non-hybrid cv. Thumper) were grown under ambient [CO2] (a[CO2], ∼400 µmol mol-1) or e[CO2] (∼700 µmol mol-1) with two water treatments (well-watered and mild drought) in a glasshouse to investigate the interdependence of leaf area development and water use. Dynamics of water use during the growing season varied depending on [CO2] and cultivars. Early stimulation of leaf growth under e[CO2], which also depended on cultivar, overcompensated for the effect of increased leaf-level water use efficiency, so that weekly water use was greater and water depletion from soil greater under e[CO2] than a[CO2]. This result shows that the balance between leaf area and water use efficiency stimulation by e[CO2] can tip towards early depletion of available soil water, so that e[CO2] does not lead to water savings, and the 'CO2 fertilisation effect' is not greater under drier conditions.


Assuntos
Brassica napus/metabolismo , Dióxido de Carbono/metabolismo , Folhas de Planta/metabolismo , Água/metabolismo , Brassica napus/crescimento & desenvolvimento , Mudança Climática , Secas , Folhas de Planta/crescimento & desenvolvimento
10.
PLoS One ; 13(6): e0198928, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29902235

RESUMO

Through stimulation of root growth, increasing atmospheric CO2 concentration ([CO2]) may facilitate access of crops to sub-soil water, which could potentially prolong physiological activity in dryland environments, particularly because crops are more water use efficient under elevated [CO2] (e[CO2]). This study investigated the effect of drought in shallow soil versus sub-soil on agronomic and physiological responses of wheat to e[CO2] in a glasshouse experiment. Wheat (Triticum aestivum L. cv. Yitpi) was grown in split-columns with the top (0-30 cm) and bottom (31-60 cm; 'sub-soil') soil layer hydraulically separated by a wax-coated, root-penetrable layer under ambient [CO2] (a[CO2], ∼400 µmol mol-1) or e[CO2] (∼700 µmol mol-1) [CO2]. Drought was imposed from stem-elongation in either the top or bottom soil layer or both by withholding 33% of the irrigation, resulting in four water treatments (WW, WD, DW, DD; D = drought, W = well-watered, letters denote water treatment in top and bottom soil layer, respectively). Leaf gas exchange was measured weekly from stem-elongation until anthesis. Above-and belowground biomass, grain yield and yield components were evaluated at three developmental stages (stem-elongation, anthesis and maturity). Compared with a[CO2], net assimilation rate was higher and stomatal conductance was lower under e[CO2], resulting in greater intrinsic water use efficiency. Elevated [CO2] stimulated both above- and belowground biomass as well as grain yield, however, this stimulation was greater under well-watered (WW) than drought (DD) throughout the whole soil profile. Imposition of drought in either or both soil layers decreased aboveground biomass and grain yield under both [CO2] compared to the well-watered treatment. However, the greatest 'CO2 fertilisation effect' was observed when drought was imposed in the top soil layer only (DW), and this was associated with e[CO2]-stimulation of root growth especially in the well-watered bottom layer. We suggest that stimulation of belowground biomass under e[CO2] will allow better access to sub-soil water during grain filling period, when additional water is converted into additional yield with high efficiency in Mediterranean-type dryland agro-ecosystems. If sufficient water is available in the sub-soil, e[CO2] may help mitigating the effect of drying surface soil.


Assuntos
Dióxido de Carbono/farmacologia , Secas , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Água/análise , Atmosfera/química , Biomassa , Dióxido de Carbono/análise , Relação Dose-Resposta a Droga , Raízes de Plantas/efeitos dos fármacos
11.
Sci Total Environ ; 586: 142-151, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28169027

RESUMO

Two peatland micro-relief forms (microforms) - hummocks and hollows - differ by their hydrological characteristics (water table level, i.e. oxic-anoxic conditions) and vegetation communities. We studied the CH4 and CO2 production potential and the localization of methanogenic pathways in both hummocks and hollows at depths of 15, 50, 100, 150 and 200cm in a laboratory incubation experiment. For this purpose, we measured CH4 and CO2 production rates, peat elemental composition, as well as δ13C values of gases and solids; the specific inhibitor of methanogenesis BES (2-bromo-ethane sulfonate, 1mM) was aimed to preferentially block the acetoclastic pathway. The cumulative CH4 production of all depths was almost one fold higher in hollows than in hummocks, with no differences in CO2. With depth, CO2 and CH4 production decreased, and the relative contribution of the hydrogenotrophic pathway of methanogenesis increased. The highest methanogenic activity among all depths and both microforms was measured at 15cm of hollows (91%) at which the highest relative contribution of acetoclastic vs. hydrogenotrophic pathway (92 and 8%, respectively) was detected. For hummocks, the CH4 production was the highest at 50cm (82%), where relative contribution of acetoclastic methanogenesis comprised 89%. The addition of 1mM BES was not selective and inhibited both methanogenic pathways in the soil. Thus, BES was less efficient in partitioning the pathways compared with the δ13C signature. We conclude that the peat microforms - dry hummocks and wet hollows - play an important role for CH4 but not for CO2 production when the effects of living vegetation are excluded.

13.
Physiol Meas ; 35(6): 965-74, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24844143

RESUMO

When a breast lump is detected through palpation, mammography or ultrasonography, the final test for characterization of the tumour, whether it is malignant or benign, is biopsy. This is invasive and carries hazards associated with any surgical procedures. The present work was undertaken to study the feasibility for such characterization using non-invasive electrical impedance measurements and machine learning techniques. Because of changes in cell morphology of malignant and benign tumours, changes are expected in impedance at a fixed frequency, and versus frequency of measurement. Tetrapolar impedance measurement (TPIM) using four electrodes at the corners of a square region of sides 4 cm was used for zone localization. Data of impedance in two orthogonal directions, measured at 5 and 200 kHz from 19 subjects, and their respective slopes with frequency were subjected to machine learning procedures through the use of feature plots. These patients had single or multiple tumours of various types in one or both breasts, and four of them had malignant tumours, as diagnosed by core biopsy. Although size and depth of the tumours are expected to affect the measurements, this preliminary work ignored these effects. Selecting 12 features from the above measurements, feature plots were drawn for the 19 patients, which displayed considerable overlap between malignant and benign cases. However, based on observed qualitative trend of the measured values, when all the feature values were divided by respective ages, the two types of tumours separated out reasonably well. Using K-NN classification method the results obtained are, positive prediction value: 60%, negative prediction value: 93%, sensitivity: 75%, specificity: 87% and efficacy: 84%, which are very good for such a test on a small sample size. Study on a larger sample is expected to give confidence in this technique, and further improvement of the technique may have the ability to replace biopsy.


Assuntos
Inteligência Artificial , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Análise por Conglomerados , Impedância Elétrica , Eletrodos , Feminino , Humanos
14.
BMC Res Notes ; 6: 121, 2013 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-23531304

RESUMO

BACKGROUND: Research on natural products has gained a wide popularity due to the potential of discovering active compounds. The antioxidant properties contained in plants have been proposed as one of the mechanisms for the observed beneficial effect. Therefore, the present study investigated the antioxidant activity and total phenolic contents of various solvent extracts of Albizia procera leaves. METHODS: Antioxidant activity of the methanol extract and its derived fractions petroleum ether (APP), carbon tetrachloride (APC), dichloromethane (APD), ethyl acetate (APE), and residual aqueous fraction (APA) of the leaves of Albizia procera was performed by in vitro chemical analyses. Total phenolic content of the APM and other five fractions were also determined. APM and its derived fractions were also subjected to preliminary phytochemical screening test for various constituents. RESULTS: Phytochemical screening revealed the presence of saponins, steroids, tannins, glycosides and flavonoids in the extracts. Amongst the extracts, APE showed the highest total phenolic content (449.18 ± 18.41mg of gallic acid equivalent/g of extract). In DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging test, the IC(50) value of APM, APP, APC, APD, APE and APA was 43.43, 63.60, 166.18, 41.15, 11.79, and 63.06 µg/mL, respectively. Therefore, among the APM and its derived fractions, APE showed the highest antioxidant activity which is comparable to that of standard ascorbic acid (AA) (IC(50) 10.12 µg/mL). The total antioxidant capacity was found to be varied in different fractions. The reducing activity on ferrous ion was ranked as APE > APD > APM > APA > APC. CONCLUSION: The above evidences suggest that APE of A. procera leaf is a potential source of natural antioxidant and can be used to prevent diseases associated with free radicals.


Assuntos
Antioxidantes/farmacologia , Fenol/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Acetatos , Antioxidantes/química , Compostos de Bifenilo/química , Sequestradores de Radicais Livres/química , Radicais Livres , Metanol , Picratos/química , Extratos Vegetais/química , Solventes
15.
BMC Res Notes ; 6: 24, 2013 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-23331970

RESUMO

BACKGROUND: Antioxidants play an important role to protect damage caused by oxidative stress (OS). Plants having phenolic contents are reported to possess antioxidant properties. The present study was designed to investigate the antioxidant properties and phenolic contents (total phenols, flavonoids, flavonols and proanthrocyanidins) of methanolic extracts from Morus alba (locally named as Tut and commonly known as white mulberry) stem barks (TSB), root bark (TRB), leaves (TL) and fruits (TF) to make a statistical correlation between phenolic contents and antioxidant potential. METHODS: The antioxidant activities and phenolic contents of methanolic extractives were evaluated by in vitro standard method using spectrophotometer. The antioxidant activities were determined by total antioxidant capacity, DPPH (1,1-diphenyl-2-picrylhydrazine) radical scavenging assay, hydroxyl radical scavenging assay, ferrous reducing antioxidant capacity and lipid peroxidation inhibition assay methods. RESULTS: Among the extracts, TSB showed the highest antioxidant activity followed by TRB, TF and TL. Based on DPPH and hydroxyl radical scavenging activity, the TSB extract was the most effective one with IC50 37.75 and 58.90 µg/mL, followed by TRB, TF and TL with IC50 40.20 and 102.03; 175.01 and 114.63 and 220.23 and 234.63 µg/mL, respectively. The TSB extract had the most potent inhibitory activity against lipid peroxidation with IC50 145.31 µg/mL. In addition, the reducing capacity on ferrous ion was in the following order: TSB > TRB > TL > TF. The content of phenolics, flavonoids, flavonols and proanthocyanidins of TSB was found to be higher than other extractives. CONCLUSION: The results indicate high correlation and regression (p-value <0 .001) between phenolic contents and antioxidant potentials of the extracts, hence the Tut plant could serve as effective free radical inhibitor or scavenger which may be a good candidate for pharmaceutical plant-based products. However, further exploration is necessary for effective use in both modern and traditional system of medicines.


Assuntos
Antioxidantes/farmacologia , Metanol/química , Morus/química , Extratos Vegetais/farmacologia , Sequestradores de Radicais Livres/farmacologia , Radical Hidroxila/química , Peroxidação de Lipídeos/efeitos dos fármacos
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