Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Pak J Biol Sci ; 24(7): 756-764, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34486294

RESUMO

<b>Background and Objective:</b> Studies on plant herbs as alternatives to chemical anaesthetics in fish species are numerous, but little is known on crustaceans. A study was conducted to investigate the efficacy of <i>C. citratus</i> Essential Oil (EO) on the induction and recovery of <i>M. rosenbergii</i>. <b>Materials and Methods:</b> The <i>C. citratus</i> EO was obtained by hydrodistillation and analyzed using GC-MS. The prawns were exposed to <i>C. citratus</i> EO and clove oil in 100-1000 and 200-1000 µL L<sup>1</sup>, respectively. Different stages of induction and recovery times were recorded. <b>Results:</b> In GC-MS, citral (78.47%) was detected as a major compound in <i>C. citratus</i> EO. Prawns reached loss equilibrium at 500-1000 µL L<sup>1</sup> <i>C. citratus</i> EO within 15.55-6.52 min. Exposure of prawn to <u><</u>500 µL L<sup>1</sup> <i>C. citratus</i> EO resulted in a high survival rate (100-94%). In clove oil, all tested concentrations caused significant induction in <i>M. rosenbergii</i> within 20.61-6.47 min. Recovery time and survival rate were significantly decreased with the increase of EO concentrations. The regression model showed the induction time in both anaesthetic agents was dependent on the concentration (R<sup>2 </sup>= 0.86-0.96). The recovery time of <i>C. citratus</i> EO-exposed prawn was dependent on the concentrations (R<sup>2 </sup>= 0.59). <b>Conclusion:</b> The study shows the potentiality of <i>C. citratus</i> EO as a natural anaesthetic in <i>M. rosenbergii</i>, although not as efficient as clove oil.

2.
Pak J Biol Sci ; 24(1): 13-18, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33683026

RESUMO

BACKGROUND AND OBJECTIVE: Effects of Cymbopogon citratus essential oil (EO) was tested on minimizing handling stress in Macrobrachium rosenbergii through the evaluation of their metabolite responses [glucose, lactate, glycogen, protein, Lactate Dehydrogenase (LDH), Malate Dehydrogenase (MDH), Acetylcholinesterase (AChE) and Alanine Aminotransferase (ALT)]. This study aimed to investigate the efficacy of C. citratus extract in the anaesthetization of M. rosenbergii. MATERIALS AND METHODS: Three treatments including control, prawn exposed to stress alone (T1) and prawn exposed to stress in the presence of C. citratus EO (T2) were tested. A C. citratus EO at 500 µL L-1 had been determined in a previous study and was selected as the critical dose to be applied as an anesthetic agent. Handling stress was induced into prawns by netting, at 2 min interval for 30 min and their hemolymph were collected to determine the metabolite responses. RESULTS: The increase of glucose, lactate and LDH of M. rosenbergii when exposed to handling stress alone (T1) in comparison to T2 (stress with anesthetic C. citratus EO) were identified. Further, a low glycogen level in parallel with low AChE activity was observed which indicates the involvement of secondary metabolites to cope with the energy demand in T1 over T2. CONCLUSION: This study indicates the efficiency of C. citratus EO to reduce stress during handling in M. rosenbergii.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 248: 119129, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33281086

RESUMO

Histamine is one of the important biomarkers for food spoilage in the food sectors. In the present study, a rapid and simple analytical tool has been developed to detect histamine as an indirect strategy to monitor food freshness level. Optical histamine sensor with carboxyl-substituted Schiff base zinc(II) complex with hydroxypropoxy side chain deposited onto titanium dioxide nanoparticles was fabricated and was found to respond successfully to histamine. The Schiff base zinc(II) complex-histamine binding generated an enhancement of the fluorescent signal. Under the optimal reaction condition, the developed sensor can detect down to 2.53 × 10-10 M in the range of between 1.0 × 10-9 and 1.0 × 10-5 M (R2 = 0.9868). Selectivity performance of the sensor towards histamine over other amines was confirmed. The sensor also displayed good reproducibility performances with low relative standard deviation values (1.45%-4.95%). Shelf-life studies suggested that the developed sensor remains stable after 60 days in histamine detection. More importantly, the proposed sensor has been successfully applied to determine histamine in salmon fillet with good recoveries. This strategy has a promising potential in the food quality assurance sectors, especially in controlling the food safety for healthy consumption among consumers.


Assuntos
Bases de Schiff , Titânio , Histamina , Reprodutibilidade dos Testes
4.
Sensors (Basel) ; 20(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32111092

RESUMO

A novel label-free electrochemical DNA biosensor was constructed for the determination of Escherichia coli bacteria in environmental water samples. The aminated DNA probe was immobilized onto hollow silica microspheres (HSMs) functionalized with 3-aminopropyltriethoxysilane and deposited onto a screen-printed electrode (SPE) carbon paste with supported gold nanoparticles (AuNPs). The biosensor was optimized for higher specificity and sensitivity. The label-free E. coli DNA biosensor exhibited a dynamic linear response range of 1 × 10-10 µM to 1 × 10-5 µM (R2 = 0.982), with a limit of detection at 1.95 × 10-15 µM, without a redox mediator. The sensitivity of the developed DNA biosensor was comparable to the non-complementary and single-base mismatched DNA. The DNA biosensor demonstrated a stable response up to 21 days of storage at 4 ℃ and pH 7. The DNA biosensor response was regenerable over three successive regeneration and rehybridization cycles.


Assuntos
Técnicas Biossensoriais/métodos , DNA/análise , Escherichia coli/isolamento & purificação , Microesferas , Dióxido de Silício/química , Tampões (Química) , Eletroquímica , Eletrodos , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Coloração e Rotulagem
5.
Talanta ; 207: 120321, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594568

RESUMO

An optical aptasensor-based sensing platform for rapid insulin detection was fabricated. Aminated porous silica microparticles (PSiMPs) were synthesized via a facile mini-emulsion method to provide large surface area for covalent immobilization of insulin-binding DNA aptamer (IGA3) by glutaraldehyde cross-linking protocol. A Nickel-salphen type complex with piperidine side chain [Ni(II)-SP] was synthesized with a simple one-pot reaction, and functionalized as an optical label due to strong π-π interaction between aromatic carbons of G-quadruplex DNA aptamer and planar aromatic groups of Ni(II)-SP to form the immobilized IGA3-Ni(II)-SP complex, i.e. the dye-labeled aptamer, thereby bringing yellow colouration to the immobilized G-quartet plane. Optical characterization of aptasensor towards insulin binding was carried out with a fiber optic reflectance spectrophotometer. The maximum reflectance intensity of the immobilized IGA3-Ni(II)-SP complex at 656 nm decreased upon binding with insulin as aptasensor changed to brownish orange colouration in the background. This allows optical detection of insulin as the colour change of aptasensor is dependent on the insulin concentration. The linear detection range of the aptasensor is obtained from 10 to 50 µIU mL-1 (R2 = 0.9757), which conformed to the normal fasting insulin levels in human with a limit of detection (LOD) at 3.71 µIU mL-1. The aptasensor showed fast response time of 40 min and long shelf life stability of >3 weeks. Insulin detection using healthy human serums with informed consent provided by participants suggests the DNA aptamer biosensor was in good agreement with ELISA standard method using BIOMATIK Human INS (Insulin) ELISA Kit.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Técnicas Biossensoriais/instrumentação , Insulina/análise , Dispositivos Ópticos , Compostos Organometálicos/química , Fenilenodiaminas/química , Aptâmeros de Nucleotídeos/química , Ensaio de Imunoadsorção Enzimática , Humanos , Concentração de Íons de Hidrogênio , Insulina/sangue , Insulina/química , Insulina/metabolismo , Limite de Detecção , Porosidade , Bases de Schiff/química , Dióxido de Silício/química , Fatores de Tempo
6.
PeerJ ; 7: e7527, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31523503

RESUMO

Background: The degradation of nucleotides and their enzymes had been widely used to evaluate fish freshness. Immediately after fish death, adenosine triphosphate (ATP) degrades into inosine-5-monophosphate (IMP) via adenosine-5-diphosphate (ADP) and adenosine-5-monophosphate (AMP). IMP degradation continues to produce inosine (ino) and hypoxanthine (Hx) and further deteriorates the fish by producing xanthine and uric acid. The dephosphorylation of IMP to Ino is carried out by the enzyme 5'-nucleotidase (5'-NT), whereas the degradation of Ino to Hx is carried out by the enzyme nucleoside phosphorylase (NP). This study assesses the application of high pressure processing (HPP) in two species of fishes; haddock (Melanogrammus aeglefinus) and herring (Clupea harengus) as a means to extend the shelf-life by slowing down the rate of nucleotides degradation. Methods: Haddock (Melanogrammus aeglefinus) and herring (Clupea harengus) fillets were subjected to HPP at 200, 250 and 300 MPa for 1 and 3 min before being stored for 14 days. In addition, 5'-NT and NP enzyme activities were determined on both fish species that were subjected to 100-600 MPa for 1 and 3 min. Results: Adenosine triphosphate, ADP and AMP in both haddock and herring were lower at higher pressure levels. Inosine (Ino) increased (p < 0.05) after treatment at higher pressures in both species. Hx in herring decreased significantly (p < 0.05) at higher pressures but not in haddock. K values are the ratio of Ino and Hx to all nucleotides. K values in haddock were not significantly (p > 0.05) affected by the pressure treatment. H values are ratio of Hx to the sum of IMP, Ino and Hx. H values in haddock were significantly decreased (p < 0.05) with increasing pressure level. F values are ratio of IMP to the sum of IMP, Ino and Hx. F values showed no significant effects (p > 0.05) after pressure treatment. Furthermore, K values in control herring were significantly higher (p < 0.05) than those of the pressure-treated samples. H values in herring decreased significantly (p < 0.05) with increasing pressure level. F values in herring showed no significant effects (p > 0.05) after pressure treatment. Pressure treatment brought a significant decrease (p < 0.05) in protein content in both haddock and herring. 5'-NT activity was 20-35 fold higher compared to NP activity in haddock and 15-44 fold higher than NP activity in herring. 5'-NT and NP activities decreased significantly with increasing pressure level in both species. Discussion: High pressure processing effectively slows down the conversion of Ino to Hx, delaying the undesirable flavour that develops in spoiling fish. The autolytic conversion of IMP to Ino by endogenous 5'-NT predominates in the earliest stages of storage is an autolytic process. However, both bacterial and endogenous NP enzymes are probably responsible for the gradual accumulation of Hx in fish. K values are recommended as a useful measurement of fish freshness.

7.
Anal Bioanal Chem ; 411(24): 6449-6461, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31392436

RESUMO

Biogenic amines have attracted interest among researchers because of their importance as biomarkers in determining the quality of food freshness in the food industry. A rapid and simple technique that is able to detect biogenic amines is needed. In this work, a new optical sensing material for one of the biogenic amines, histamine, based on a new zinc(II) salphen complex was developed. The binding of zinc(II) complexes without an electron-withdrawing group (complex 1) and with electron-withdrawing groups (F, complex 2; Cl, complex 3) to histamine resulted in enhancement of fluorescence. All complexes exhibited high affinity for histamine [binding constant of (7.14 ± 0.80) × 104, (3.33 ± 0.03) × 105, and (2.35 ± 0.14) × 105 M-1, respectively]. Complex 2 was chosen as the sensing material for further development of an optical sensor for biogenic amines in the following step since it displayed enhanced optical properties in comparison with complexes 1 and 3. The optical sensor for biogenic amines used silica microparticles as the immobilisation support and histamine as the analyte. The optical sensor had a limit of detection for histamine of 4.4 × 10-12 M, with a linear working range between 1.0 × 10-11 and 1.0 × 10-6 M (R2 = 0.9844). The sensor showed good reproducibility, with a low relative standard deviation (5.5 %). In addition, the sensor exhibited good selectivity towards histamine and cadaverine over other amines, such as 1,2-phenylenediamine, triethylamine, and trimethylamine. Recovery and real sample studies suggested that complex 2 could be a promising biogenic amine optical sensing material that can be applied in the food industry, especially in controlling the safety of food for it to remain fresh and healthy for consumption.


Assuntos
Aminas Biogênicas/análise , Fluorometria/métodos , Fenilenodiaminas/química , Espectrofotometria Ultravioleta/instrumentação , Compostos de Zinco/química , Histamina/análise , Limite de Detecção , Reprodutibilidade dos Testes
8.
J Toxicol ; 2019: 2529569, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281355

RESUMO

The aim of this study was to investigate the antioxidant potentials, subacute toxicity, and beneficiary effects of methanolic extract of pomelo (Citrus grandis L. Osbeck) in rats. Long Evans rats were divided into four groups of eight animals each. The rats were orally treated with three doses of pomelo (250, 500, and 1000 mg/kg) once daily for 21 days. Pomelo extract contained high concentrations of polyphenols, flavonoids, and ascorbic acid while exhibiting high 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and ferric reducing antioxidant power values. There was no significant change in the body weight, percentage water content, and relative organ weight at any administered doses. In addition, no significant alterations in the hematological parameters were also observed. However, rats which received 1000 mg/kg dose had a significant reduction in some serum parameters, including alanine transaminase (15.29%), alkaline phosphatase (2.5%), lactate dehydrogenase (15.5%), γ-glutamyltransferase (20%), creatinine (14.47%), urea (18.50%), uric acid (27.14%), total cholesterol (5.78%), triglyceride (21.44%), low-density lipoprotein cholesterol (40.74%), glucose (2.48%), and all atherogenic indices including cardiac risk ratio (24.30%), Castelli's risk index-2 (45.71%), atherogenic coefficient (42%), and atherogenic index of plasma (25%) compared to control. In addition, the highest dose (1000 mg/kg) caused a significant increase in iron (12.07%) and high-density lipoprotein cholesterol (8.87%) levels. Histopathological findings of the vital organs did not indicate any pathological changes indicating that pomelo is nontoxic, safe, and serves as an important source of natural antioxidants. In addition, the fruit extract has the potential to ameliorate hepato- and nephrotoxicities and cardiovascular diseases as well as iron deficiency anemia.

9.
Talanta ; 198: 358-370, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30876573

RESUMO

An optical genosensor based on Schiff base complex (Zn2+ salphen) DNA label and acrylic microspheres (AMs) as polymer support of the capturing DNA probe (cpDNA) was developed for dengue virus serotype 2 (DEN-2) detection via reflectance spectrophotometric method. The solid-state optical DNA biosensor showed high selectivity and specificity up to one-base mismatch in the target DNA sequence owing to the salphen chemical structure that is rich in localized electrons, and allowed π-π stacking interaction between stacked base pairs of double-stranded DNA (dsDNA). The reflectometric DNA microsensor demonstrated a broad linear detection range towards DEN-2 DNA from 1 × 10-15 M to 1 × 10-3 M with a low limit of detection (LOD) obtained at 1.21 × 10-16 M. The DNA biosensor gave reproducible optical response with a satisfactory relative standard deviation (RSD) at 3.1%, (n = 3), and the reflectance response was stable even after four regeneration cycles of the DNA biosensor. The optical genosensor was proven comparable with standard reverse transcription polymerase chain reaction (RT-PCR) in detecting DEN-2 genome acquired from clinical samples of serum, urine and saliva of dengue virus infected patients under informed consent. The developed reflectometric DNA biosensor is advantageous in offering an early DEN-2 diagnosis, when fever symptom started to manifest in patient.


Assuntos
Resinas Acrílicas/química , Vírus da Dengue/isolamento & purificação , Fenilenodiaminas/química , Zinco/química , Sondas de DNA/química , Microesferas , Imagem Óptica
10.
Ital J Food Saf ; 7(3): 6846, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30538958

RESUMO

An aqueous extraction of moringa (Moringa oleifera) leaves were prepared as the edible coats for keeping the quality of the giant freshwater prawn (Macrobrachium rosenbergii). In addition, the antioxidant properties and activity; total phenolic content (TPC), total flavonoid contents (TFC), free radical scavenging activity (DPPH), and ferric reducing antioxidant power (FRAP) of moringa leaves were also determined. The phenolic compounds and antioxidant properties in the moringa leaves are low; 16.14 mgGAEg-1 for TPC; 5.57 mgQEg-1 for TFC; 1.36 mgTEg-1 for DPPH; and 3.05 mgTEg-1 for FRAP. The experiment was further conducted by coating the M. rosenbergii with moringa leaves extraction before chilled storage at 4°C for 15 days. Moringa leaves extraction were effectively reduced the microflora count in M. rosenbergii (P<0.05). Total volatile basis nitrogen (TVB-N) value showed a significant (P<0.05) lower amount in treated samples compared to the controls. Melanosis were obvious in controls compared to the treated samples. After 15 days of chilled storage, the sensory properties; taste, texture and odour of treated samples were acceptable by the panelists. Biopreservation of moringa leaves extraction significantly benefits in keeping the quality of M. rosenbergii.

11.
Nutrients ; 10(9)2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150582

RESUMO

The incidence of prostate cancer malignancy along with other cancer types is increasing worldwide, resulting in high mortality rate due to lack of effective medications. Moringa oleifera has been used for the treatment of communicable and non-communicable ailments across tropical countries, yet, little has been documented regarding its effect on prostate cancer. We evaluated the acute toxicity and apoptosis inducing effect of glucomoringin-isothiocyanate rich soluble extracts (GMG-ITC-RSE) from M. oleifera in vivo and in vitro, respectively. Glucomoringin was isolated, identified, and characterized using fundamental analytical chemistry tools where Sprague-Dawley (SD) rats, murine fibroblast (3T3), and human prostate adenocarcinoma cells (PC-3) were used for acute toxicity and bioassays experiments. GMG-ITC-RSE did not instigate adverse toxic reactions to the animals even at high doses (2000 mg/kg body weight) and affected none of the vital organs in the rats. The extract exhibited high levels of safety in 3T3 cells, where more than 90% of the cells appeared viable when treated with the extract in a time-dependent manner even at high dose (250 µg/mL). GMG-ITC-RSE significantly triggered morphological aberrations distinctive to apoptosis observed under microscope. These findings obviously revealed the putative safety of GMG-ITC-RSE in vivo and in vitro, in addition to its anti-proliferative effect on PC-3 cells.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Isotiocianatos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Ramnose/análogos & derivados , Células 3T3 , Adenocarcinoma/patologia , Animais , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/toxicidade , Feminino , Humanos , Isotiocianatos/análise , Isotiocianatos/toxicidade , Masculino , Camundongos , Células PC-3 , Neoplasias da Próstata/patologia , Ratos Sprague-Dawley , Ramnose/análise , Ramnose/farmacologia , Ramnose/toxicidade , Medição de Risco
12.
Artigo em Inglês | MEDLINE | ID: mdl-29861774

RESUMO

The current study aimed to investigate the ameliorative effects of two types of mushrooms, Ganoderma lucidum (GL) and Auricularia polytricha (AP), against carbofuran- (CF) induced toxicity in rats. Male Wistar rats (n = 42) were divided into six equal groups. The rats in the negative control group received oral administration of CF at 1 mg/kg with the normal diet for 28 days. The treatment groups received oral administration of ethanolic extract of GL or AP at 100 mg/kg followed by coadministration of CF at 1 mg/kg with the normal diet for the same experimental period, respectively. In the CF alone treated group, there were significant decreases in the erythrocytic and thrombocytic indices but increases in the concentrations of the total leukocytes, including the agranulocytes. A significant increase in all of the liver function biomarkers except albumin, in lipid profiles except high-density lipoprotein, and in the kidney function markers occurred in the negative control group compared to the rats of the normal control and positive control groups. The coadministration of mushroom extracts significantly ameliorated the toxic effects of the CF. The GL mushroom extract was more efficacious than that of the AP mushroom, possibly due to the presence of high levels of phenolic compounds and other antioxidants in the GL mushroom.

13.
Nutrients ; 10(5)2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29738500

RESUMO

Crucifer vegetables, Brassicaceae and other species of the order Brassicales, e.g., Moringaceae that are commonly consumed as spice and food, have been reported to have potential benefits for the treatment and prevention of several health disorders. Though epidemiologically inconclusive, investigations have shown that consumption of those vegetables may result in reducing and preventing the risks associated with neurodegenerative disease development and may also exert other biological protections in humans. The neuroprotective effects of these vegetables have been ascribed to their secondary metabolites, glucosinolates (GLs), and their related hydrolytic products, isothiocyanates (ITCs) that are largely investigated for their various medicinal effects. Extensive pre-clinical studies have revealed more than a few molecular mechanisms of action elucidating multiple biological effects of GLs hydrolytic products. This review summarizes the most significant and up-to-date in vitro and in vivo neuroprotective actions of sulforaphane (SFN), moringin (MG), phenethyl isothiocyanate (PEITC), 6-(methylsulfinyl) hexyl isothiocyanate (6-MSITC) and erucin (ER) in neurodegenerative diseases.


Assuntos
Glucosinolatos/farmacologia , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Brassica/química , Humanos , Isotiocianatos/farmacologia , Sulfetos/farmacologia , Tiocianatos/farmacologia , Verduras/química
14.
Sensors (Basel) ; 18(4)2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29649118

RESUMO

A sensitive and selective optical DNA biosensor was developed for dengue virus detection based on novel square-planar piperidine side chain-functionalized N,N'-bis-4-(hydroxysalicylidene)-phenylenediamine-nickel(II), which was able to intercalate via nucleobase stacking within DNA and be functionalized as an optical DNA hybridization marker. 3-Aminopropyltriethoxysilane (APTS)-modified porous silica nanospheres (PSiNs), was synthesized with a facile mini-emulsion method to act as a high capacity DNA carrier matrix. The Schiff base salphen complexes-labelled probe to target nucleic acid on the PSiNs renders a colour change of the DNA biosensor to a yellow background colour, which could be quantified via a reflectance transduction method. The reflectometric DNA biosensor demonstrated a wide linear response range to target DNA over the concentration range of 1.0 × 10-16-1.0 × 10-10 M (R² = 0.9879) with an ultralow limit of detection (LOD) at 0.2 aM. The optical DNA biosensor response was stable and maintainable at 92.8% of its initial response for up to seven days of storage duration with a response time of 90 min. The reflectance DNA biosensor obtained promising recovery values of close to 100% for the detection of spiked synthetic dengue virus serotypes 2 (DENV-2) DNA concentration in non-invasive human samples, indicating the high accuracy of the proposed DNA analytical method for early diagnosis of all potential infectious diseases or pathological genotypes.


Assuntos
Técnicas Biossensoriais , DNA , Vírus da Dengue , Humanos , Níquel , Fenilenodiaminas , Piperidinas
15.
Anal Bioanal Chem ; 410(9): 2363-2375, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29504083

RESUMO

A novel electrochemical DNA biosensor for ultrasensitive and selective quantitation of Escherichia coli DNA based on aminated hollow silica spheres (HSiSs) has been successfully developed. The HSiSs were synthesized with facile sonication and heating techniques. The HSiSs have an inner and an outer surface for DNA immobilization sites after they have been functionalized with 3-aminopropyltriethoxysilane. From field emission scanning electron microscopy images, the presence of pores was confirmed in the functionalized HSiSs. Furthermore, Brunauer-Emmett-Teller (BET) analysis indicated that the HSiSs have four times more surface area than silica spheres that have no pores. These aminated HSiSs were deposited onto a screen-printed carbon paste electrode containing a layer of gold nanoparticles (AuNPs) to form a AuNP/HSiS hybrid sensor membrane matrix. Aminated DNA probes were grafted onto the AuNP/HSiS-modified screen-printed electrode via imine covalent bonds with use of glutaraldehyde cross-linker. The DNA hybridization reaction was studied by differential pulse voltammetry using an anthraquinone redox intercalator as the electroactive DNA hybridization label. The DNA biosensor demonstrated a linear response over a wide target sequence concentration range of 1.0×10-12-1.0×10-2 µM, with a low detection limit of 8.17×10-14 µM (R2 = 0.99). The improved performance of the DNA biosensor appeared to be due to the hollow structure and rough surface morphology of the hollow silica particles, which greatly increased the total binding surface area for high DNA loading capacity. The HSiSs also facilitated molecule diffusion through the silica hollow structure, and substantially improved the overall DNA hybridization assay. Graphical abstract Step-by-step DNA biosensor fabrication based on aminated hollow silica spheres.


Assuntos
Técnicas Biossensoriais/métodos , DNA Bacteriano/análise , Infecções por Escherichia coli/microbiologia , Escherichia coli/isolamento & purificação , Dióxido de Silício/química , Microbiologia da Água , Aminação , Condutometria/métodos , DNA Bacteriano/genética , Escherichia coli/genética , Ouro/química , Humanos , Ácidos Nucleicos Imobilizados/química , Ácidos Nucleicos Imobilizados/genética , Limite de Detecção , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico/métodos
16.
Pharm Biol ; 55(1): 1937-1945, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28675957

RESUMO

CONTEXT: Turmeric (Curcuma longa L. [Zingiberaceae]) is used in the treatment of a variety of conditions including pesticide-induced toxicity. OBJECTIVE: The study reports the antioxidant properties and the protective effects of turmeric against carbofuran (CF)-induced toxicity in rats. MATERIALS AND METHODS: The antioxidant potential was determined by using free radicals scavenging activity and ferric reducing antioxidant power values. Male Wistar rats were randomly divided into four groups, designated as control, turmeric (100 mg/kg/day), CF (1 mg/kg/day) and turmeric (100 mg/kg/day) + CF (1 mg/kg/day) treatments. All of the doses were administered orally for 28 consecutive days. The biological activity of the turmeric and CF was determined by using several standard biochemical methods. RESULTS: Turmeric contains high concentrations of polyphenols (8.97 ± 0.15 g GAEs), flavonoids (5.46 ± 0.29 g CEs), ascorbic acid (0.06 ± 0.00 mg AEs) and FRAP value (1972.66 ± 104.78 µM Fe2+) per 100 g of sample. Oral administration of CF caused significant changes in some of the blood indices, such as, mean corpuscular volume, corpuscular hemoglobin, white blood cell, platelet distribution width and induced severe hepatic injuries associated with oxidative stress, as observed by the significantly higher lipid peroxidation (LPO) levels when compared to control, while the activities of cellular antioxidant enzymes (including superoxide dismutase and glutathione peroxidase) were significantly suppressed in the liver tissue. DISCUSSION AND CONCLUSION: Turmeric supplementation could protect against CF-induced hematological perturbations and hepatic injuries in rats, plausibly by the up-regulation of antioxidant enzymes and inhibition of LPO to confer the protective effect.


Assuntos
Células Sanguíneas/efeitos dos fármacos , Carbofurano/toxicidade , Curcuma , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Células Sanguíneas/metabolismo , Células Sanguíneas/patologia , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/patologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/patologia , Fígado/metabolismo , Fígado/patologia , Masculino , Modelos Animais , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Extratos Vegetais/isolamento & purificação , Distribuição Aleatória , Ratos , Ratos Wistar
17.
J Fluoresc ; 27(3): 1009-1023, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28224358

RESUMO

The platinum(II) salphen complex N,N'-Bis-4-(hydroxysalicylidene)-phenylenediamine-platinum(II); (1) and its two derivatives containing hydroxyl functionalized side chains N,N'-bis-[4-[[1-(2-hydroxyethoxy)] salicylidene] phenylenediamine-platinum(II); (2) and N,N'-bis-[4-[[1-(3-hydroxypropoxy)] salicylidene] phenylenediamine-platinum(II); (3) were synthesized and characterized. The structures of the complexes were confirmed by 1H and 13C NMR spectroscopy, FTIR, ESI-MS and CHN elemental analyses. The effects of the hydroxyl substituent on the spectral properties and the DNA binding behaviors of the Pt(II) complexes were explored. The binding mode and interactions of these complexes with duplex DNA (calf thymus DNA and porcine DNA) and also single-stranded DNA were studied by UV-Vis and emission DNA titration. The complexes interact with DNA by intercalation binding mode with the binding constants in the order of magnitude (Kb = 104 M-1, CT-DNA) and (Kb = 105 M-1, porcine DNA). The intercalation of the complex in the DNA structure was proposed to happen by π-π stacking due to its square-planar geometry and aromatic rings structure. The phosphorescence emission spectral characteristics of Pt(II) complexes when interacted with DNA have been studied. Also, the application of the chosen hydroxypropoxy side chains complex (3) as an optical DNA biosensor, specifically for porcine DNA was investigated. These findings will be valuable for the potential use of the platinum(II) salphen complex as an optical DNA biosensor for the detection of porcine DNA in food products.


Assuntos
Técnicas Biossensoriais/métodos , Complexos de Coordenação/química , DNA/análise , DNA/metabolismo , Fenilenodiaminas/química , Platina/química , Animais , Suínos
18.
Food Chem Toxicol ; 108(Pt B): 451-457, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27725206

RESUMO

Rhodomyrtus tomentosa (Aiton) Hassk. has a wide spectrum of pharmacological effects and has been used to treat wounds, colic diarrhoea, heartburns, abscesses and gynaecopathy. The potential antiproliferative activities of R. tomentosa extracts from different solvents were evaluated in vitro on HepG2, MCF-7 and HT 29 cell lines while antioxidant activity was monitored by radical scavenging assay (DPPH), copper reducing antioxidant capacity (CUPRAC) and ß-carotene bleaching assay. Extracts from R. tomentosa show the viability of the cells in concentration-dependent manner. According to the IC50 obtained, the ethyl acetate extracts showed significant antiproliferative activity on HepG2 (IC50 11.47 ± 0.280 µg/mL), MCF-7 (IC50 2.68 ± 0.529 µg/mL) and HT 29 (IC50 16.18 ± 0.538 µg/mL) after 72 h of treatment. Bioassay guided fractionation of the ethyl acetate extract led to the isolation of lupeol. Methanol extracts show significant antioxidant activities in DPPH (EC50 110.25 ± 0.005 µg/ml), CUPRAC (EC50 53.84 ± 0.004) and ß-carotene bleaching (EC50 58.62 ± 0.001) due to the presence of high total flavonoid and total phenolic content which were 110.822 ± 0.017 mg butylated hydroxytoluene (BHT)/g and 190.467 ± 0.009 mg gallic acid (GAE)/g respectively. Taken together, the results extracts show the R. tomentosa as a potential source of antioxidant and antiproliferative efficacy.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Myrtaceae/química , Extratos Vegetais/farmacologia , Solventes/química , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Extratos Vegetais/química
19.
Asian Pac J Cancer Prev ; 17(8): 3675-86, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27644601

RESUMO

Moringa oleifera Lam, family Moringaceae, is a perennial plant which is called various names, but is locally known in Malaysia as "murungai" or "kelor". Glucomoringin, a glucosinolate with from M. oleifera is a major secondary metabolite compound. The seeds and leaves of the plant are reported to have the highest amount of glucosinolates. M. oleifera is well known for its many uses health and benefits. It is claimed to have nutritional, medicinal and chemopreventive potentials. Chemopreventive effects of M. oleifera are expected due to the existence of glucosinolate which it is reported to have the ability to induce apoptosis in anticancer studies. Furthermore, chemopreventive value of M. oleifera has been demonstrated in studies utilizing its leaf extract to inhibit the growth of human cancer cell lines. This review highlights the advantages of M. oleifera targeting chemoprevention where glucosinolates could help to slow the process of carcinogenesis through several molecular targets. It is also includes inhibition of carcinogen activation and induction of carcinogen detoxification, anti-inflammatory, anti-tumor cell proliferation, induction of apoptosis and inhibition of tumor angiogenesis. Finally, for synergistic effects of M. oleifera with other drugs and safety, essential for chemoprevention, it is important that it safe to be consumed by human body and works well. Although there is promising evidence about M. oleifera in chemoprevention, extensive research needs to be done due to the expected rise of cancer in coming years and to gain more information about the mechanisms involved in M. oleifera influence, which could be a good source to inhibit several major mechanisms involved in cancer development.


Assuntos
Carcinogênese/efeitos dos fármacos , Moringa oleifera/química , Neoplasias/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Quimioprevenção/métodos , Glucosinolatos/farmacologia , Humanos
20.
Electrophoresis ; 37(20): 2649-2656, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27434368

RESUMO

Online preconcentration using electrokinetic supercharging (EKS) was proposed to enhance the sensitivity of separation for endocrine disrupting chemical (methylparaben (MP)) and phenolic pollutants (2-nitrophenol (NP) and 4-chlorophenol (CP)) in water sample. Important EKS and separation conditions such as the concentration of BGE; the choice of terminating electrolyte (TE); and the injection time of leading electrolyte (LE), sample, and TE were optimized. The optimum EKS-CE conditions were as follows: BGE comprising of 12 mM sodium tetraborate pH 10.1, 100 mM sodium chloride as LE hydrodynamically injected at 50 mbar for 30 s, electrokinetic injection (EKI) of sample at -3 kV for 200 s, and 100 mM CHES as TE hydrodynamically injected at 50 mbar for 40 s. The separation was conducted at negative polarity mode and UV detection at 214 nm. Under these conditions, the sensitivity of analytes was enhanced from 100- to 737-fold as compared to normal CZE with hydrodynamic injection, giving LOD of 4.89, 5.29, and 53 µg/L for MP, NP and CP, respectively. The LODs were adequate for the analysis of NP and CP in environmental water sample having concentration at or lower than their maximum admissible concentration limit (240 and 2000 µg/L for NP and CP). The LOD of MP can be suitable for the analysis of MP exists at mid-microgram per liter level, even though the LOD was slightly higher than the concentration usually found in water samples (from ng/L to 1 µg/L). The method repeatabilities (%RSD) were in the range of 1.07-2.39% (migration time) and 8.28-14.0% (peak area).


Assuntos
Eletroforese Capilar/métodos , Disruptores Endócrinos/isolamento & purificação , Fenóis/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Disruptores Endócrinos/análise , Disruptores Endócrinos/química , Limite de Detecção , Fenóis/análise , Fenóis/química , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...