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1.
Molecules ; 28(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36677591

RESUMEN

Consumption of white rice (WR) has been shown to predispose individuals to metabolic disorders. However, brown rice (BR), which is relatively richer in bioactive compounds, possesses anti-glycaemic and antioxidant effects. In this study, fifteen cultivars of paddy rice that are predominantly consumed in North West Nigeria were analysed for their nutritional composition, bioactive contents and effects on metabolic outcomes in a fruit fly model. Gene expression analyses were conducted on the whole fly, targeting dPEPCK, dIRS, and dACC. The protein, carbohydrate, and fibre contents and bioactives of all BR cultivars were significantly different (p < 0.05) from the WR cultivars. Moreover, it was demonstrated that the glucose and trehalose levels were significantly higher (p < 0.05), while glycogen was significantly lower (p < 0.05) in the WR groups compared to the BR groups. Similarly, the expression of dACC and dPEPCK was upregulated, while that of dIRS was downregulated in the WR groups compared to the BR groups. Sex differences (p < 0.05) were observed in the WR groups in relation to the nutrigenomic effects. Our findings confirm metabolic perturbations in fruit flies following consumption of WR via distortion of insulin signalling and activation of glycogenolysis and gluconeogenesis. BR prevented these metabolic changes possibly due to its richer nutritional composition.


Asunto(s)
Enfermedades Metabólicas , Oryza , Glucemia/metabolismo , Insulina/metabolismo , Nutrigenómica , Oryza/química , Drosophila , Animales
2.
Molecules ; 27(12)2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35745063

RESUMEN

The way cells communicate is not fully understood. However, it is well-known that extracellular vesicles (EVs) are involved. Researchers initially thought that EVs were used by cells to remove cellular waste. It is now clear that EVs function as signaling molecules released by cells to communicate with one another, carrying a cargo representing the mother cell. Furthermore, these EVs can be found in all biological fluids, making them the perfect non-invasive diagnostic tool, as their cargo causes functional changes in the cells upon receiving, unlike synthetic drug carriers. EVs last longer in circulation and instigate minor immune responses, making them the perfect drug carrier. This review sheds light on the latest development in EVs isolation, characterization and, application as therapeutic cargo, novel drug loading techniques, and diagnostic tools. We also address the advancement in plant-derived EVs, their characteristics, and applications; since plant-derived EVs only recently gained focus, we listed the latest findings. Although there is much more to learn about, EV is a wide field of research; what scientists have discovered so far is fascinating. This paper is suitable for those new to the field seeking to understand EVs and those already familiar with it but wanting to review the latest findings.


Asunto(s)
Vesículas Extracelulares , Animales , Comunicación Celular , Portadores de Fármacos , Mamíferos
3.
Crit Rev Biotechnol ; 36(4): 585-93, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25641328

RESUMEN

Plant bioresources are relied upon as natural, inexpensive, and sustainable remedies for the management of several chronic diseases worldwide. Plants have historically been consumed for medicinal purposes based on traditional belief, but this trend is currently changing. The growing interest in the medicinal properties of plant bioresources stems from concerns of side effects and other adverse effects caused by synthetic drugs. This interest has yielded a better understanding of the roles of plant bioactive compounds in health promotion and disease prevention, including the underlying mechanisms involved in such functional effects. The desire to maximize the potential of phytochemicals has led to the development of "rich fractions," in which extracts contain bioactive compounds in addition to elevated levels of the primary compound. Although a rich fraction effectively increases the bioactivity of the extract, the standardization and quality assurance process can be challenging. However, the supercritical fluid extraction (SFE) system is a promising green technology in this regard. Future clinical and pharmacological studies are needed to fully elucidate the implications of these preparations in the management of human diseases, thereby fostering a move toward evidence-based medicine.


Asunto(s)
Benzoquinonas/farmacología , Fenilpropionatos/farmacología , Extractos Vegetales/farmacología , Tocotrienoles/farmacología , Animales , Humanos , Fitoterapia
4.
Molecules ; 21(6)2016 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-27322226

RESUMEN

Increasing evidence from both experimental and clinical studies depicts the involvement of oxidative stress in the pathogenesis of various diseases. Specifically, disruption of homeostatic redox balance in accumulated body fat mass leads to obesity-associated metabolic syndrome. Strategies for the restoration of redox balance, potentially by exploring potent plant bioactives, have thus become the focus of therapeutic intervention. The present study aimed to bioprospect the potential use of the curculigoside-cinnamic acid-rich fraction from Molineria latifolia rhizome as an antioxidant therapeutic agent. The ethyl acetate fraction (EAF) isolated from M. latifolia rhizome methanolic extract (RME) contained the highest amount of phenolic compounds, particularly curculigoside and cinnamic acid. EAF demonstrated glycation inhibitory activities in both glucose- and fructose-mediated glycation models. In addition, in vitro chemical-based and cellular-based antioxidant assays showed that EAF exhibited high antioxidant activities and a protective effect against oxidative damage in 3T3-L1 preadipocytes. Although the efficacies of individual phenolics differed depending on the structure and concentration, a correlational study revealed strong correlations between total phenolic contents and antioxidant capacities. The results concluded that enriched phenolic contents in EAF (curculigoside-cinnamic acid-rich fraction) contributed to the overall better reactivity. Our data suggest that this bioactive-rich fraction warrants therapeutic potential against oxidative stress-related disorders.


Asunto(s)
Antioxidantes/química , Hypoxidaceae/química , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Células 3T3-L1 , Animales , Antioxidantes/administración & dosificación , Benzoatos/administración & dosificación , Benzoatos/química , Cinamatos/administración & dosificación , Cinamatos/química , Flavonoides/química , Glucósidos/administración & dosificación , Glucósidos/química , Ratones , Oxidación-Reducción , Fenoles/química , Picratos/química , Extractos Vegetales/administración & dosificación , Rizoma/química
5.
J Food Sci Technol ; 51(11): 3269-76, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26396320

RESUMEN

Cinnamon deodorised aqueous extract (CinDAE) was prepared and evaluated for its total phenolic (315.3 ± 35.4 mg GAE/g) and flavonoid (99.3 ± 9.6 mg RE/g) contents. Stabilizing efficiency of CinDAE, for chicken meatballs, was measured against oxidative deterioration as function of storage time under chilled conditions. For this purpose, oxidative stability [2-thiobarbituric acid reactive substances (TBARS); peroxide value (PV)], colour and sensory acceptability were measured in the control meatballs (C), and those stabilized with 200 ppm of: CinDAE (T1), ascorbic acid (T2), BHA/BHT (50/50; w/w) (T3). In comparison to "C", induction period (IP) and redness (a* value) of the stabilized samples (T1, T2 and T3) were increased, while PV and TBARS were decreased throughout storage (8 ± 1 °C) significantly (p < 0.05). Meanwhile, CinDAE slightly decreased L* value of the meatballs as compared to other tested samples. Conclusively, CinDAE improved stability and redness of chicken meatballs without negatively affecting its sensory acceptability (Hedonic test) up to a comparable extent to that of ascorbic acid/BHA/BHT and may potentially function as a dietary antioxidant for meat products.

6.
Int J Biol Macromol ; 274(Pt 1): 133329, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38908640

RESUMEN

Neoterically, food packaging systems designed solely for prolonging shelf life or monitoring freshness could not fulfil the dynamic demands of consumers. In this current investigation, using the solvent casting method, a versatile halochromic indicator was created by integrating black currant anthocyanin and cinnamon essential oil-loaded Pickering emulsion into a starch/gelatin matrix. The resulting indicator film underwent scrutiny for its structural, pH-sensitive, antioxidant, and antimicrobial attributes. Unexpectedly, the amalgamation of anthocyanin and essential oil led to decreased antioxidant activity, dropping from 73.23 ± 2.17 to 28.87 ± 2.50 mg Trolox equivalent/g sample. Additionally, no discernible antimicrobial properties were detected in the composite film sample against both Staphylococcus aureus and Escherichia coli. Fourier transform infrared analyses unveiled robust intermolecular interactions among the film-forming components, providing insights into the observed antagonistic effect. The indicator film displayed distinctive colour changes corresponding to the fresh (greyish-brown), onset of decomposition (khaki), and spoiled (dark green) stages of the stored fish sample. This highlights its promising potential for providing real-time indications of food spoilage. These findings are important for the efficient design of composite films incorporating anthocyanins and essential oils. They serve as a guide towards their potential use as multifunctional packaging materials in the food industry.

7.
Cell Mol Neurobiol ; 33(8): 1159-69, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24101432

RESUMEN

Thymoquinone (TQ), a bioactive constituent of Nigella sativa Linn (N. sativa) has demonstrated several neuropharmacological attributes. In the present study, the neuroprotective properties of TQ were investigated by studying its anti-apoptotic potential to diminish ß-amyloid peptide 1-40 sequence (Aß1-40)-induced neuronal cell death in primary cultured cerebellar granule neurons (CGNs). The effects of TQ against Aß1-40-induced neurotoxicity, morphological damages, DNA condensation, the generation of reactive oxygen species, and caspase-3, -8, and -9 activation were investigated. Pretreatment of CGNs with TQ (0.1 and 1 µM) and subsequent exposure to 10 µM Aß1-40 protected the CGNs against the neurotoxic effects of the latter. In addition, the CGNs were better preserved with intact cell bodies, extensive neurite networks, a loss of condensed chromatin and less free radical generation than those exposed to Aß1-40 alone. TQ pretreatment inhibited Aß1-40-induced apoptosis of CGNs via both extrinsic and intrinsic caspase pathways. Thus, the findings of this study suggest that TQ may prevent neurotoxicity and Aß1-40-induced apoptosis. TQ is, therefore, worth studying further for its potential to reduce the risks of developing Alzheimer's disease.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Benzoquinonas/farmacología , Cerebelo/patología , Neuronas/patología , Fármacos Neuroprotectores/farmacología , Neurotoxinas/toxicidad , Animales , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Células Cultivadas , Cromatina/metabolismo , ADN/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Activación Enzimática/efectos de los fármacos , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Neuritas/patología , Neuronas/efectos de los fármacos , Neuronas/enzimología , Ratas , Ratas Sprague-Dawley
8.
Nutrients ; 15(13)2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37447162

RESUMEN

Diabetes is associated with an imbalance between oxidants and antioxidants, leading to oxidative stress. This imbalance contributes to the development and progression of diabetic complications. Similarly, renal and liver diseases are characterised by oxidative stress, where an excess of oxidants overwhelms the antioxidant defense mechanisms, causing tissue damage and dysfunction. Restoring the oxidant-antioxidant balance is essential for mitigating oxidative stress-related damage under these conditions. In this current study, the efficacy of stingless bee honey (SBH) and its phenolic-rich extract (PRE) in controlling the oxidant-antioxidant balance in high-fat diet- and streptozotocin/nicotinamide-induced diabetic rats was investigated. The administration of SBH and PRE improved systemic antioxidant defense and oxidative stress-related measures without compromising liver and renal functioning. Analyses of the liver, skeletal muscle and adipose tissues revealed differences in their capacities to scavenge free radicals and halt lipid peroxidation. Transcriptional alterations hypothesised tissue-specific control of KEAP1-NRF2 signalling by upregulation of Nrf2, Ho1 and Sod1 in a tissue-specific manner. In addition, hepatic translational studies demonstrated the stimulation of downstream antioxidant-related protein with upregulated expression of SOD-1 and HOD-1 protein. Overall, the results indicated that PRE and SBH can be exploited to restore the oxidant-antioxidant imbalance generated by diabetes via regulating the KEAP1-NRF2 signalling pathway.


Asunto(s)
Diabetes Mellitus Experimental , Miel , Abejas , Ratas , Animales , Antioxidantes/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Oxidantes , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Estrés Oxidativo , Fenoles/farmacología
9.
Nutrients ; 15(10)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37242273

RESUMEN

This study evaluated the acute and sub-acute toxicity of B. amyloliquefaciens HTI-19 (isolated from stingless bee honey) in female Sprague Dawley rats. In an acute toxicity study, the rats received a low dosage (1 × 109 CFU·mL-1), medium dosage (3 × 109 CFU·mL-1), or high dosage (1 × 1010 CFU·mL-1) of B. amyloliquefaciens HTI-19 daily orally by syringe-feeding for 14 days. For the subacute toxicity study, rats received a low dosage (1 × 109 CFU·mL-1) or a high dosage (1 × 1010 CFU·mL-1) for 28 days. The probiotic feeding in acute and sub-acute toxicity studies showed no mortality or significant abnormalities in rats throughout the experimental period. In week 2 of the acute study, the body weight of the rats showed a significant increase (p < 0.05) compared to the control. By gross and microscopic examination of organs, no evidently significant changes were observed in the morphology of organs. Serum biochemical tests and blood hematology tests also revealed no treatment-related changes. Overall, these data indicated that oral administration of B. amyloliquefaciens HTI-19 up to 1 × 109 CFU·mL-1 for 28 days can be considered safe.


Asunto(s)
Bacillus amyloliquefaciens , Miel , Probióticos , Abejas , Femenino , Ratas , Animales , Ratas Sprague-Dawley , Peso Corporal
10.
Adv Pharmacol Pharm Sci ; 2023: 8127695, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38090376

RESUMEN

Breast cancer is the most common cancer diagnosed in women, and in 2020, there were 684, 996 deaths due to this disease. Epidermal growth factor receptors (EGFRs) and their respective ligands have been blamed for the pathogenesis and resistance to treatment in specific breast cancer cases. With EGFR having four homologues: EGFR1, EGFR2, EGFR3, and EGFR4, in-depth understanding of EGFR biology led to the discovery of small-molecule inhibitors and antibodies against this receptor. Gefitinib (GEF), a tyrosine kinase inhibitor of EGFR1, possesses a vast potential for treatment against breast cancer and is supported by a multiplicity of experiments. Unfortunately, in clinical trials, GEF did not show the outcomes expected with complete response and disease progress. This is due to incomplete understanding of the molecular mechanisms involved in EGFR signaling and endocrine sensitivity. Hence, additional in-depth experiments are needed regarding various molecular pathways and crosstalk pathways to comprehend GEF's action mechanism thoroughly in breast cancer patients. In this review, the role of EGFR in the development and pathogenesis of breast cancer and the pharmacokinetics and pharmacotherapy of GEF for the treatment of breast cancer have been elaborated. Nanomedicines synthesized with GEF have shown positive experimental response, paving a promising path for GEF against breast cancer.

11.
J Microbiol Immunol Infect ; 56(3): 558-565, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36804307

RESUMEN

BACKGROUND: An extended interval between the two primary doses may reduce the risk of myocarditis/pericarditis after COVID-19 mRNA vaccination. Taiwan has implemented a two-dose regimen with a 12-week interval for adolescents. Here we present nationwide data of myocarditis/pericarditis following COVID-19 vaccinations. METHODS: Data on adverse events of myocarditis/pericarditis were from the Taiwan Vaccine Adverse Events Reporting System between March 22, 2021, and February 9, 2022. The reporting rates according to sex, age, and vaccine type were calculated. We investigated the rates among young individuals under different two-dose intervals and among those who received two doses of different vaccines. RESULTS: Among 204 cases who met the case definition of myocarditis/pericarditis, 75 cases occurred after the first dose and 129 after the second. The rate of myocarditis/pericarditis after COVID-19 vaccination varied across sex and age groups and was highest after the second dose in males aged 12-17 years (126.79 cases per million vaccinees) for the BNT162b2 vaccine and in males aged 18-24 years (93.84 cases per million vaccinees) for the mRNA-1273 vaccine. The data did not suggest an association between longer between-dose interval and lower rate of myocarditis/pericarditis among males and females aged 18-24 or 25-29 years who received two doses of the BNT162b2 or mRNA-1273 vaccine. Rates of myocarditis/pericarditis in males and females aged 18-49 years after receiving ChAdOx1-S - mRNA-1273 vaccination was significantly higher than after ChAdOx1-S - ChAdOx1-S vaccination. CONCLUSIONS: Myocarditis and pericarditis are rare following mRNA vaccination, with higher risk occurring in young males after the second dose.


Asunto(s)
COVID-19 , Miocarditis , Pericarditis , Adolescente , Femenino , Humanos , Masculino , Vacuna nCoV-2019 mRNA-1273 , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Miocarditis/epidemiología , Miocarditis/etiología , Pericarditis/epidemiología , Pericarditis/etiología , ARN Mensajero , Vacunación/efectos adversos , Adulto Joven , Adulto
12.
Int J Mol Sci ; 13(11): 15387-400, 2012 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-23203132

RESUMEN

Quantitative structure-retention relationships (QSRRs) have successfully been developed for naturally occurring phenolic compounds in a reversed-phase liquid chromatographic (RPLC) system. A total of 1519 descriptors were calculated from the optimized structures of the molecules using MOPAC2009 and DRAGON softwares. The data set of 39 molecules was divided into training and external validation sets. For feature selection and mapping we used step-wise multiple linear regression (SMLR), unsupervised forward selection followed by step-wise multiple linear regression (UFS-SMLR) and artificial neural networks (ANN). Stable and robust models with significant predictive abilities in terms of validation statistics were obtained with negation of any chance correlation. ANN models were found better than remaining two approaches. HNar, IDM, Mp, GATS2v, DISP and 3D-MoRSE (signals 22, 28 and 32) descriptors based on van der Waals volume, electronegativity, mass and polarizability, at atomic level, were found to have significant effects on the retention times. The possible implications of these descriptors in RPLC have been discussed. All the models are proven to be quite able to predict the retention times of phenolic compounds and have shown remarkable validation, robustness, stability and predictive performance.


Asunto(s)
Cromatografía de Fase Inversa , Fenoles/química , Modelos Químicos , Modelos Teóricos , Redes Neurales de la Computación , Relación Estructura-Actividad Cuantitativa
13.
Int J Mol Sci ; 13(6): 7496-7507, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22837707

RESUMEN

The present study was conducted to evaluate the antioxidant properties of wheat and rice flours under simulated gastrointestinal pH condition. After subjecting the wheat and rice flour slurries to simulated gastrointestinal pH condition, both slurries were centrifuged to obtain the crude phenolic extracts for further analyses. Extraction yield, total contents of phenolic and flavonoids were determined as such (untreated) and under simulated gastrointestinal pH condition (treated). 1,1-diphenyl-2-picrylhydrazyl radical (DPPH(•)) scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical cation (ABTS(•+)) scavenging activity, ferric reducing antioxidant power (FRAP), beta-carotene bleaching (BCB) and iron chelating activity assays were employed for the determination of antioxidant activity of the tested samples. In almost all of the assays performed, significant improvements in antioxidant properties (p < 0.05) were observed in both flours after treatment, suggesting that wheat and rice flours contain considerably heavy amounts of bound phenolics, and that their antioxidant properties might be improved under gastrointestinal digestive conditions.


Asunto(s)
Antioxidantes/química , Harina , Jugo Gástrico/química , Oryza/química , Triticum/química , Flavonoides/química , Concentración de Iones de Hidrógeno , Fenoles/química
14.
Int J Mol Sci ; 13(7): 8987-8997, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22942747

RESUMEN

Sweet potato is known to be rich in healthful antioxidants, but the stability of its antioxidant properties under gastrointestinal pH is very much unknown. Hence, this study aimed to evaluate the changes in antioxidant properties (total contents of phenolics and flavonoids as well as antioxidant activity) of sweet potato flour (SPF) under simulated gastrointestinal pH conditions. It was found that the yield of SPF crude phenolic extract increased from 0.29 to 3.22 g/100 g SPF upon subjection to gastrointestinal pH conditions (p < 0.05). Also elevated significantly were the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of SPF (p < 0.05). In summary, the antioxidant properties of SPF were enhanced under gastrointestinal pH conditions, suggesting that SPF might possess a considerable amount of bound phenolic and other antioxidative compounds. The antioxidant properties of SPF are largely influenced by pH and thus might be enhanced during the in vivo digestive process.


Asunto(s)
Antioxidantes/química , Harina , Jugo Gástrico/química , Ipomoea batatas/química , Concentración de Iones de Hidrógeno
15.
Int J Mol Sci ; 13(6): 6651-6664, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22837655

RESUMEN

In this study, leaves of three indigenous varieties of Mulberry namely, Morus alba L., Morus nigra L. and Morus rubra L. were investigated for their antioxidant potential and their proximate composition was determined. The yields of 80% methanolic extracts ranged between 8.28-13.89%. The contents of total phenolics (TPC), total flavonoids (TFC) and ascorbic acid (AA) ranged between 16.21-24.37 mg gallic acid equivalent (GAE)/g, 26.41-31.28 mg rutin equivalent (RE)/g and 0.97-1.49 mg/g, respectively. The antioxidant activity of leaf extracts was evaluated by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)) radical scavenging actity, 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid (ABTS(•+)) radical cation scavenging capacity and ferric ion reducing power and values ranged between 1.89-2.12, 6.12-9.89 and 0.56-0.97 mM Trolox equivalent/g of dried leaves, respectively. The investigated features reveal good nutritive and antioxidant attributes of all the varieties with mutually significant differences.


Asunto(s)
Antioxidantes/química , Depuradores de Radicales Libres/química , Morus/química , Extractos Vegetales/química , Hojas de la Planta/química , Ácido Ascórbico/química , Benzotiazoles/química , Compuestos de Bifenilo/química , Cationes , Flavonoides/análisis , Flavonoides/química , Radicales Libres/química , Lípidos/química , Metanol/química , Morus/clasificación , Fenol/química , Fenoles/análisis , Picratos/química , Rutina/química , Especificidad de la Especie , Ácidos Sulfónicos/química
16.
Molecules ; 17(11): 12612-21, 2012 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-23099617

RESUMEN

A sequential solvent extraction scheme was employed for the extraction of antioxidant compounds from kenaf (Hibiscus cannabinus L.) seeds. Yield of extracts varied widely among the solvents and was the highest for hexane extract (16.6% based on dry weight basis), while water extract exhibited the highest total phenolic content (18.78 mg GAE/g extract), total flavonoid content (2.49 mg RE/g extract), and antioxidant activities (p < 0.05). DPPH and hydroxyl radical scavenging, β-carotene bleaching, metal chelating activity, ferric thiocyanate and thiobarbituric acid reactive substances assays were employed to comprehensively assess the antioxidant potential of different solvent extracts prepared sequentially. Besides water, methanolic extract also exhibited high retardation towards the formation of hydroperoxides and thiobarbituric acid reactive substances in the total antioxidant activity tests (p < 0.05). As conclusion, water and methanol extracts of kenaf seed may potentially serve as new sources of antioxidants for food and nutraceutical applications.


Asunto(s)
Depuradores de Radicales Libres/química , Hibiscus/química , Fenoles/química , Extractos Vegetales/química , Semillas/química , Compuestos de Bifenilo/química , Quelantes/química , Quelantes/aislamiento & purificación , Flavonoides/química , Flavonoides/aislamiento & purificación , Depuradores de Radicales Libres/aislamiento & purificación , Radicales Libres/química , Hexanos/química , Hierro/química , Extracción Líquido-Líquido , Fenoles/aislamiento & purificación , Picratos/química , Extractos Vegetales/aislamiento & purificación , Solventes/química , Sustancias Reactivas al Ácido Tiobarbitúrico/química , Tiocianatos/química , Agua/química , beta Caroteno/química
17.
Molecules ; 17(6): 7584-94, 2012 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-22713349

RESUMEN

The influence of both acidic and basic hydrolysis on the yield, total phenolic content and antioxidative capacity of methanolic extract of germinated brown rice (GBR) was studied. Total phenolic content (TPC), total flavonoid content (TFC), 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical cation scavenging, and ferric reducing antioxidant power (FRAP) tests were used for the measurement of antioxidant ability. There was a significant difference p < 0.05) in the TPC and DPPH radical scavenging assay results when comparing neutral with acidic and basic catalysed hydrolysis. The yield of the crude extract was slightly higher in acidic hydrolysis than in basic hydrolysis p > 0.05). The TPC and TFC were highest in acidic hydrolysis. A significant correlation was observed between ABTS radical cation scavenging and FRAP. The antioxidant activity measured using DPPH radical scavenging assay showed high activity in acidic hydrolysis, while the ABTS radical cationscavenging activity and FRAP showed the highest values in basic hydrolysis. The samples were further evaluated using HPLC to determine the individual phenolic concentrations in different hydrolytic media contributing to the antioxidant effects. This study revealed that acidic and basic hydrolysis can improve the yield, phenolic content, and antioxidant activity of germinated brown rice.


Asunto(s)
Antioxidantes/química , Flavonoides/química , Oryza/química , Fenoles/química , Extractos Vegetales/química , Ácidos/química , Catálisis , Depuradores de Radicales Libres/química , Germinación , Hidrólisis
18.
Molecules ; 17(5): 6020-32, 2012 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-22614857

RESUMEN

This study was conducted to investigate the chemical and nutritional composition of Artemisia annua leaves in addition to determination of antioxidant potential of their extracts prepared in different solvents. Chemical composition was determined by quantifying fat, protein, carbohydrate, fiber, tocopherol, phytate, and tannin contents. Extraction of A. annua leaves, for antioxidant potential evaluation, was carried out using five solvents of different polarities, i.e., hexane, chloroform, ethyl acetate, methanol and water. Antioxidant potential was evaluated by estimating total phenolic (TPC), flavonoid (TFC) contents, ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), DPPH radical scavenging activity and lipid peroxidation. Efficiency of different solvents was compared for the yield of antioxidant extracts from leaf samples and a clear variation was observed. The highest TPC, TFC, TEAC, DPPH radical scavenging and lowest lipid peroxidation were observed in MeOH extracts, whereas aqueous extract exhibited high ferric reducing antioxidant power; suggesting MeOH to be the most favorable extractant.


Asunto(s)
Antioxidantes/química , Artemisia annua/química , Extractos Vegetales/química , Hojas de la Planta/química , Solventes , Flavonoides/química , Radicales Libres/química , Peroxidación de Lípido , Fenoles/química
19.
Front Plant Sci ; 13: 999270, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36247633

RESUMEN

The tropical fruit industry in Malaysia makes up a large proportion of the agriculture sector, contributing to the local economy. Due to their high sugar and water content, tropical fruits are prone to pathogenic infections, providing optimal microorganism growth conditions. As one of the largest exporters of these fruits globally, following other Southeast Asian countries such as Thailand, Indonesia and the Philippines, the quality control of exported goods is of great interest to farmers and entrepreneurs. Traditional methods of managing diseases in fruits depend on chemical pesticides, which have attracted much negative perception due to their questionable safety. Therefore, the use of natural products as organic pesticides has been considered a generally safer alternative. The extracts of aromatic plants, known as essential oils or plant extracts, have garnered much interest, especially in Asian regions, due to their historical use in traditional medicine. In addition, the presence of antimicrobial compounds further advocates the assessment of these extracts for use in crop disease prevention and control. Herein, we reviewed the current developments and understanding of the use of essential oils and plant extracts in crop disease management, mainly focusing on tropical fruits. Studies reviewed suggest that essential oils and plant extracts can be effective at preventing fungal and bacterial infections, as well as controlling crop disease progression at the pre and postharvest stages of the tropical fruit supply chain. Positive results from edible coatings and as juice preservatives formulated with essential oils and plant extracts also point towards the potential for commercial use in the industry as more chemically safe and environmentally friendly biopesticides.

20.
Antibiotics (Basel) ; 10(11)2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34827303

RESUMEN

In the honey industry, heat treatments are usually applied to maintain honey's quality and shelf life. Heat treatment is used to avoid crystallisation and allow the easy use of honey, but treatment with heat might affect the antioxidant and antibacterial activities, which are the immediate health effects of honey. This study will determine the effect of heat treatment on Malaysian and Australian stingless bee honey (SBH) produced by the common bee species in both countries. Eighteen honey samples were subjected to heat at 45 °C, 55 °C and 65 °C for one hour and subsequently analysed for their total phenolic content (TPC), total flavonoid content (TFC), DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and minimum inhibitory concentration (MIC). The results show that all samples had high TPC, TFC and antioxidant activities before the treatment. The heat treatments did not affect (p < 0.05) the TPC, TFC and antioxidant activities in most samples, but did inhibit the antibacterial activities consistently in most of the samples, regardless of the bee species and country of origin. This study also confirms a strong correlation between TPC and TFC with FRAP activities for the non-heated and heated honey samples (p < 0.05). Other heat-sensitive bioactive compounds in SBH should be measured to control the antibacterial properties present.

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