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Hancornia speciosa Gomes (HS) is a Brazilian fruit tree used in inflammatory disorders by folk medicine. Here we sought to investigate the antioxidant and hepatoprotective properties of HS fruit ju...

The Commelina erecta L. (C. erecta) also known as erva-de-santa-luzia is reported by local population to have medical properties against some pathological conditions. In this study, two extracts of C. erecta leaves (aqueous and ethanolic) were phytochemically analysed and evaluated for their in-vitro antioxidant activities by DPPH, TBARS, NO assays and cell viability assays. The ultra-high performance liquid chromatography followed by tandem mass spectrometry analysis showed the presence of rutin and caffeic acid in aqueous and ethanolic extract. The total polyphenols in aqueous and ethanolic extracts found were 142.7 ± 3.0 and 123.1 ± 5.8 μg/mL of GAE, respectively. The ethanolic extract (5 mg/mL) inhibits TBARS by 33.8%, and the aqueous extract (5 mg/mL) exhibited scavenger property against nitric oxide derivatives to an extent of 77.8%. In cell culture, both extracts improved cell survivability under H2O2 induced oxidative stress. Thus, C. erecta extract is a good candidate to become a phytotherapic medicine.

A simple method has been proposed for the determination of cocaine's major adulterants (caffeine, levamisole, lidocaine, phenacetin, diltiazem, and hydroxyzine) in human urine by dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) in combination with high-performance liquid chromatography - photodiode array detector (HPLC-PDA). The reversed-phase chromatographic separation was obtained with a column C18 extended (250×4.6mm; 5μm; 80A) in gradient elution mode using acetonitrile-trifluoroacetic acid 0.026% (v,v) (pH=2.5) at 1mLmin-1 as mobile phase, at 25°C, and detection at 235nm. The analysis time was 25min. This condition had the best resolution factors (>1.15), retention factors (>0.68), number of plates (>2094.9), and separation factors (>1.05) for all targets, indicating a good separation. The kind of extraction and dispersive solvent were investigated for unifactorial design. The buffer pH, the volume of extraction and disperser solvent, and the amount of salt were optimized for full factorial design. Under optimum conditions, human urine samples were alkalized with 0.5M sodium phosphate buffer (pH 10) and added to sodium chloride (20%m/v). Acetonitrile (150μL) and 1-dodecanol (30μL) were used as dispersive and extraction solvent, respectively. The method presented linear range of 312.5-3125ngmL-1 to caffeine and levamisole and 187.5-1875ngmL-1 to lidocaine, phenacetin, diltiazem, and hydroxyzine. The limit of quantification was 187.5ngmL-1 to lidocaine, phenacetin, diltiazem, and hydroxyzine and 312.5ngmL-1 for caffeine and levamisole. The recovery mean values were between 6.0 and 42.6%. The method showed good precision and accuracy, with within- and between-run relative standard deviation and relative error less than 15%. The samples were stable after freeze-thaw cycle and short-term room temperature stability tests. Besides, this method was satisfactorily applied in urine of cocaine users. It is expected that this method, which was the first to combine the use of DLLME-SFO and HPLC-PDA for the determination of cocaine's major adulterants in human urine, will contribute to the accuracy in the diagnosis of acute intoxication, the proper planning of therapeutic measures, as well as to the favorable prognostic of cocaine intoxicated patients.

In Brazil, despite the existence of various environmental laws to protect mangroves, this ecosystem has been affected by a variety of anthropogenic activities. The São Francisco River Estuary (SFRE, Brazil Northeast) comprises significant mangrove forests, important for human populations, and is included in an Environmental Protected Area of sustainable use which does not have a management plan. This work assessed and mapped anthropogenic activities on the mangroves of this estuary and provided a number of guidelines for a local management plan. Satellite images (SPOT 5 and CBERS 2B) of 2008 were processed and a land use/cover map (study area size: 192.4km2) produced and verified by fieldwork. About 93% (178.8km2) of the study area is occupied by natural cover such as: sandy coastal vegetation (147.3km2, 77%), mangroves (30.1km2, 15.7%) and intertidal flats (1.4km2, 0.7%), while 7% (13.6km2) is occupied by human activities as aquaculture (4.5km2, 2.4%) and agriculture (9km2, 4.7%). These uses are spatially distributed within mangroves, accounting for approximately one quarter (7.8km2) of its area, which may indicate the conversion of these forests. Shrimp farming is the main anthropogenic activity, occupying the highest area and occurring within the tallest Rhizophora mangle forests (tree height >15m). We recommend that a management plan for the SFRE considers: the implementation of sustainable aquaculture practices (e.g. small-scale without deforestation of mangroves, use of native species, effluent treatment, socio-economic equity), strategies for the compliance of the laws regarding shrimp farming license and operation and support the creation of community-based cooperatives for the execution of sustainable aquaculture. © 2013 Elsevier Ltd.

Hexokinases play a critical role in the cellular uptake and utilization of glucose. As such, they are of fundamental importance to all cells. By catalyzing glucose to produce glucose-6-phosphate, hexokinases control the first irreversible step of glucose metabolism and initiate all major pathways of glucose consumption. Our objective was to develop and validate highly sensitive and selective high-performance liquid chromatography with photodiode array detector (HPLC-PDA) assays allowing the determination of adenosine diphosphate, which was used for the determination of hexokinase activity. Samples were analyzed by HPLC-PDA using a C18 analytical column (250 × 4.6 mm) for chromatographic separation. Optimal detection was achieved based on isocratic elution with a mobile phase consisting of a mixture of sodium phosphate monobasic buffer and methanol. This method met all of the requirements of specificity, sensitivity, linearity, precision, accuracy and stability generally accepted in bioanalytical chemistry and was successfully applied to a study of hexokinase activity in an alloxan-induced diabetic rat model. Determination of hexokinase activity will permit characterization of cellular metabolic state in many diseases, such as cancer and diabetes.

It has been suggested that iron overload may be carcinogenic. In thepresent study, we evaluated the effect of plasma and prostate caro-tenoid concentration on oxidative DNA damage in 12-week-old Wistarrats treated with intraperitoneal ( ip ) ferric nitrilotriacetate (Fe-NTA)(10 mg Fe/kg). Plasma s-carotene and lycopene concentrations weremeasured as a function of time after ip injection of carotenoids (10 mgkg -1 day s-carotene or lycopene) in rats. The highest total plasmaconcentration was reached 3 and 6 h after ip injection of lycopene ors-carotene, respectively. After 5 days of carotenoid treatment, lyco-pene and s-carotene were present in the 0.10-0.51 nmol/g wet tissuerange in the prostate. Using a sensitive method to detected 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) by HPLC/EC, the level of8-oxodGuo in rat prostate DNA was significantly higher (6.3 ± 0.6residues/10 6 dGuo) 3 h after Fe-NTA injection compared with controlrats (1.7 ± 0.3 residues/10 6 dGuo). Rats supplemented with lycopeneor s-carotene for 5 days prior to Fe-NTA treatment showed a reductionof about 70% in 8-oxodGuo levels to almost control levels. Comparedwith control rats, the prostate of Fe-NTA-treated animals showed a78% increase in malondialdehyde accumulation. Lycopene or s-carotene pre-treatment almost completely prevented lipid damage.Epidemiological studies have suggested a lower risk of prostatecancer in men reporting a higher consumption of tomato products.However, before associating this effect with tomato sauce constitu-ents, more information is required. The results described here maycontribute to the understanding of the protective effects of carotenoidsagainst iron-induced oxidative stress.

Coconut water (CW) is a natural nutritious beverage, which contains several biologically active compounds that are traditionally used in the treatment of diarrhea and rehydration. Several works with CW have been related with antioxidant activity, which is very important in the diabetic state. To evaluate the hypoglycemic and nephroprotective activities of CW, alloxan-induced diabetic rats were pre- and post-treated by gavage with CW (3 mL/kg), caffeic acid (CA) (10 and 15 mg/kg), and acarbose (Acb) (714 μg/kg) during a period of 16 days. Body weight, blood glucose, glycated hemoglobin (HbA1c), and Amadori products in plasma and kidney homogenates were evaluated in all groups and used as parameters for the monitoring of the diabetic state. The results showed that rats of the CW+diabetic group had maintenance in blood glucose compared with the control group (P.05) in addition to a decrease of HbA1c levels and increase of body weight when compared with the diabetic group rats (P.05). The animals of the CA and CA+diabetic groups did not have significant variation of body weight (P.05) during the experiment; however, they showed decrease in their HbA1c and urea levels in plasma as well as Amadori products in kidney homogenates when compared with the diabetic group (P.05). Our results indicate that CW has multiple beneficial effects in diabetic rats for preventing hyperglycemia and oxidative stress caused by alloxan.

Experimental and epidemiological evidence suggests that lycopene, a carotenoid present in tomatoes, tomato products, and several fruits and vegetables, may play a role in preventing certain cancers in humans. We have investigated the effect of lycopene pretreatment on lipid peroxidation, oxidative damage to DNA, and histopathological changes in liver of animals subjected to intraperitoneal (ip) ferric nitrilotriacetate (Fe-NTA) administration. Compared with control rats, liver of Fe-NTA-treated animals showed a significant increase in the 8-oxo-7,8-dihydro-2'-deoxyguanosine level and a 75% increase in malondialdehyde accumulation concomitant with histopathological changes. Five days of lycopene pretreatment (10 mg/kg body weight, ip) almost completely prevented liver biomolecule oxidative damage and protected the tissue against the observed histological alterations.

Coconut water contains several uncharacterized substances and is widely used in the human consumption. In this paper we detected and quantified ascorbic acid and caffeic acid and total phenolics in several varieties of coconut using HPLS/MS/MS (25.8 ± 0.6 µg/mL and 1.078 ± 0.013 µg/mL and 99.7 µg/mL, respectively, in the green dwarf coconut water, or 10 mg and 539 µg and 39.8 mg for units of coconut consumed, 500 ± 50 mL). The antioxidant potential of four coconut varieties (green dwarf, yellow dwarf, red dwarf and yellow Malaysian) was compared with two industrialized coconut waters and the lyophilized water of the green dwarf variety. All varieties were effective in scavenging the DPPH radical (IC50=73 µL) and oxide nitric (0.1 mL with an IP of 29.9%) as well as in inhibiting the in vitro production of thiobarbituric acid reactive substances (1 mL with an IP of 34.4%), highlighting the antioxidant properties of the green dwarf which it is the most common used. In cell culture, the green dwarf water was efficient in protecting against oxidative damages induced by hydrogen peroxide. A água de coco contém várias substâncias não caracterizadas e é amplamente utilizada na alimentação humana. Neste estudo, foram detectados e quantificados ácido ascórbico e ácido cafeico e polifenóis totais em diversas variedades de coco, e usando HPLC/MS/MS (25,8 ± 0,6 µg/mL, 1,078 ± 0,013 µg/mL and 99,7 µg/mL, respectivamente, em água de coco do anão verde, ou 10 mg, 539 µg e 39,8 mg por unidades de coco consumido, 500 ± 50 mL). O potencial antioxidante da água de coco das quatro variedades de coqueiro (anão verde, anão amarelo, anão vermelho e amarelo malasiano) foi comparada com água de coco industrializada e água liofilizada da variedade anão verde. Todas as variedades foram eficazes - com destaque para as propriedades antioxidantes do anão verde, uma vez que é o mais comum usado – no sequestro do radical DPPH (IC50=73 µL), óxido nítrico (0,1 mL com IP de 29,9%) e inibindo a produção de espécies reativas com o ácido tiobarbitúrico (1 mL com IP de 34,4%) in vitro. Em cultura de células, a água de coco da variedade anão verde foi eficiente na proteção contra danos oxidativos induzidos por peróxido de hidrogênio.

O excesso de óxido nítrico (NO) produzido por indução da enzima óxido nítrico sintase (iNOS) participa do desenvolvimento de inúmeras desordens que conduzem à perda da homeostasia. O estresse oxidativo gerado pelo aumento da produção endógena de NO pode levar a efeitos de toxidade induzida, tais como peroxidação lipídica, nitração de proteínas e danos ao DNA. Compostos que sejam capazes de sequestrar o radical NO podem diminuir a toxicidade das espécies reativas de nitrogênio (RNS), atuando na modulação de processos inflamatórios. Trabalhos realizados com alga da espécie Bryothamnion triquetrum (Gmelin) Howe, demonstraram que a mesma apresenta ação antioxidante, tendo sido eficiente no sequestro do radical DPPH, além de inibição da peroxidação lipídica, com uma atividade comparável ao ácido ascórbico e ao α-tocoferol. Este estudo objetivou avaliar a capacidade de sequestro do radical NO in vitro pelo extrato metanólico da Bryothamnion triquetrum. Os resultados obtidos revelaram a presença de polifenóis sendo que todas as concentrações testadas (1,0; 2,5; 7,5; 10,0 mg/mL) foram capazes de inibir a formação de nitrito a partir de uma solução de nitroprussiato de sódio 5 mM sendo a concentração de 7,5 mg/mL a que apresentou maior percentual de inibição com 46,6%. The excess of nitric oxide (NO) produced by induction of nitric oxide sintase enzyme (iNOS) participates in the development of countless disorders that lead to the loss of homeostasis. The oxidative stress generated by the increase of endogenous production of NO can lead to some effects of induced toxicity, such as fatty per oxidation, nitration of proteins and DNA damages. Compounds that scavenge the NO radical can reduce the toxicity of reactive nitrogen species (RNS), and act in the modulation of inflammatory processes. Works accomplished with the alga species Bryothamnion triquetrum (Gmelin) Howe demonstrated that it presents an antioxidant action, and it is efficient in the scavenging of DPPH radical and in the inhibition of fatty per oxidation, with activity comparable to the ascorbic acid and α-tocoferol. This study aimed to evaluate the capacity of NO radical scavenging in vitro for the methanol extract of the alga Bryothamnion triquetrum. The results revealed that the presence of poliphenol in all tested concentrations (1,0; 2,5; 7,5; 10,0 mg/mL) was capable to inhibit the nitrite formation, starting from a solution of sodium nitroprussiate 5 mM whose concentration of 7,5 mg/mL presented the largest inhibition percentage of 46,6%.

A high incidence of cancer has been correlated with chronic iron overload, and carotenoids are of interest as possible anticarcinogens. We have investigated the effect of lycopene on lipid peroxidation and on the formation of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo) in CV1-P monkey cells exposed to ferric nitrilotriacetate (Fe-NTA) plus ascorbate. Cells supplemented with lycopene (20 pmol/10 6 cells) showed a reduction of 86% in Fe-NTA/ascorbate-induced lipid peroxidation (TBARS). Levels of 8-oxodGuo rose from 1.59 ± 0.09 residues/10 6 dGuo in the control cells to 14.02 ± 0.41 residues/10 6 dGuo after incubation with (1:4 mM) Fe-NTA/ascorbate (40 μM). Lycopene supplementation decreased in 77% the 8-oxodGuo levels in Fe-NTA/ascorbate-treated cells. These results indicate that lycopene can protect mammalian cells against membrane and DNA damage and possibly play a protective role against tumor promotion associated with oxidative damage.