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The role of antioxidants in cancer has been controversial for a long time. Although the public’s belief is that antioxidants prevent and/or inhibit cancer, there is increasing evidence to suggest the opposite: that cancer cells require antioxidants to survive. We wanted to interrogate the role of antioxidants in cancer by investigating both upstream regulators and downstream effectors of antioxidant signaling. We have identified protein tyrosine phosphatase non-receptor type 12 (PTPN12) as a novel regulator of antioxidant signaling in cancer. PTPN12 reduces reactive oxygen species (ROS) levels by promoting activity of the forkhead box O (FOXO) family of antioxidant transcription factors. We have also elucidated the impact of glutathione (GSH), the most abundant antioxidant in the cell, on tumorigenesis. We have found that GSH is required for cancer initiation, yet dispensable once transformation has occurred due to compensation provided by the thioredoxin (TXN) antioxidant pathway. Together, these studies expand our knowledge of the role of antioxidants in cancer and provide numerous avenues of research for the future.

The anthocyanins show efficient antioxidant properties and free radical scavenging properties which result in various health-promoting benefits. This research investigated the ability of anthocyanidins to distribute into mitochondria and protect mitochondria from oxidative stress. In an in vitro study, the uptake of pure cyanidin and quercetin, and their 3-glucosylated forms into isolated rat liver mitochondria was tested, along with their effects on mitochondrial oxidative stress parameters. The absorption of cyanidin was significantly higher (67% uptake of 125 µM) than the other three flavonoids. Measurements indicated that the cyanidin was taken up into or tightly bound by mitochondria. Also, results suggested that cyanidin uptake was partially dependent on membrane potential. When incubated together (internally and externally) with mitochondria all tested flavonoids decreased reactive oxygen species (ROS) generation during mitochondrial respiration, and inhibited lipid peroxidation to different extents. Importantly, pre-loaded CY showed much stronger effects against oxidative stress in two analyses than other flavonoids. Due to its greater uptake by mitochondria, cyanidin may provide greater protection in vivo. In an in vivo study, cyanidin, quercetin and their 3-glucosides were administered into rat tail vein to give a dose of 7.6 µmol/Kg body weight. Cyanidin and its glucoside had greater affinity to liver and kidney than did quercetin and its glucoside; particularly, all test tissues contained a significantly higher amount of cyanidin than other test flavonoids. Also, cyanidin accumulated more in liver mitochondria than other flavonoids, and consistent with in vitro results was present in mitochondria to a much greater extent than cyanidin glucoside. However, delivery of the flavonoids at this dose did not significantly affect the liver mitochondria susceptibility to lipid peroxidation or the level of endogenous tissue oxidative damage. Altogether the results show that cyanidin can rapidly and efficiently accumulate in mitochondria, wherein it exhibits strong bio-antioxidant activity against oxidative stress and may help protect mitochondrial function and integrity. Also, the anthocyanidin and its 3-glucoside have greater ability than flavonols to accumulate in organs; especially cyanidin presented in liver mitochondria to a much greater extent. Cyanidin could be a potent natural antioxidant compound that is effective in mitochondria-protective therapies.

Faculty of Health SCiences School of Therapantic Sciences(pharmacy and Pharmaciology) 9604111j vanessa8@absamail.co.za / The genus Salvia, commonly known as the sages is a member of the mint family (Lamiaceae). In Latin, ‘sage’ means "to save" and the Romans called it "sacred herb". Throughout history it has been used for depression, fever, respiratory infections, women's complaints, sleep inducer, diuretic, gargles and sick room use. The essential oil is reported to have anti-inflammatory, antimicrobial, antioxidant, antiseptic, antispasmodic, astringent, diuretic, antihypertensive and insecticidal properties. Of the 900 species recorded worldwide, 30 are indigenous to South Africa where they are used extensively in traditional healing. The aerial parts of twelve samples were hydrodistilled and the essential oil analysed by GC-MS. The essential oil composition varied quantitatively and qualitatively within the different Salvia species analysed. Linalool was the only compound that was present in all the essential oils. β-caryophyllene and caryophyllene oxide were present in all essential oil with the exception of S. stenophylla. The essential oil as well as methanol and acetone extracts were tested for antimicrobial activity on a number of bacteria and fungi. No species showed activity against Cryptococcus neoformans, Candida albicans nor Alternaria alternata. All test samples studied demonstrated variable degrees of antibacterial activity with the exception of four test samples; S. disermas (methanol and acetone) from the Walter Sisulu Botanical Garden; S. disermas (methanol) from Mossel Bay and S. lanceolata (methanol). Gram-positive organisms were more sensitive to the test samples than the Gram-negative organisms. In general, the extracts were far more active than the essential oils. Thin layer chromatography indicated that all methanol extracts possess antioxidant activity. All methanol extracts contain the antioxidant compound, rosmarinic acid. It is evident that, in addition to rosmarinic acid, other polar and non-polar compounds are present in all Salvia species that also act as antioxidants.

Orientador: José Antônio Dell'Aqua Júnior / Resumo: O espermatozoide exige um fornecimento constante de energia para a manutenção de suas funções celulares e quando desafiado por processos de criopreservação do sêmen, sofrem danos irreversíveis. Para o desenvolvimento de técnicas que visam o aumento da longevidade espermática, é necessário considerar que mesmo em metabolismo basal, o espermatozoide necessita de substratos para garantir sua motilidade e poder fecundante após a ejaculação. Para atender suas demandas energéticas, estudos recomendam o uso de nutrientes exógenos, como o piruvato de sódio e a coenzima Q10 (CoQ10), substratos fundamentais na bioenergética celular. Visto a importância da refrigeração de sêmen em garanhões e o potencial destas substâncias em melhorar os parâmetros seminais atuando como substrato energético e antioxidante, respectivamente, o presente trabalho tem por objetivo abordar aspectos relacionados ao metabolismo espermático, bem como o papel do piruvato e CoQ10 visando minimizar os efeitos deletérios da refrigeração sobre a qualidade do sêmen equino. Foram adicionadas diferentes concentrações de piruvato de sódio e da CoQ10 ao sêmen de garanhões considerados “good coolers” (GC) e “bad coolers” (BC). Primeiramente, foram estabelecidas as concentrações mais eficazes de piruvato e CoQ10 no diluente de refrigeração BotuSêmen® (Botupharma Botucatu/SP Brasil) para preservar os parâmetros espermáticos na refrigeração a 5° C por até 48 horas. Foi utilizado 1 ejaculado de 25 garanhões das raças Quarto de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The spermatozoa require a constant supply of energy for the maintenance of their cellular functions and when challenged by processes of cryopreservation of the semen, they suffer irreversible damages. For the development of techniques that aim to increase sperm longevity, it is necessary to consider that even in basal metabolism, the spermatozoa require substrate to ensure their motility and fertilizing power after ejaculation. To attend their energy demands, studies recommend the use of exogenous nutrients, such as sodium pyruvate and coenzyme Q10 (CoQ10), key substrates in cellular bioenergetics. Considering the importance of semen cooling in stallions and the potential of these substances to improve seminal parameters acting as an energetic and antioxidant substrate, this review aims to address aspects related to cooling, as well as the role of sodium pyruvate and CoQ10 in minimizing the effects of cooling on the quality of equine semen. Different concentrations of sodium pyruvate and CoQ10 have been added to semen from good coolers (GC) and bad coolers (BC). First, the most effective concentrations of sodium pyruvate and CoQ10 in the BotuSêmen® extender (Botupharma Botucatu / SP Brazil) were established to preserve the sperm parameters at 5°C for up to 48 hours. Each ejaculate was split into 7 treatments, with sodium pyruvate and CoQ10 being added at concentrations of 1 mmol/l (P1), 2 mmol/l (P2), 3 mmol/l sodium pyruvate (P3), 25 µmol/l (Q25), 50 µmol/l (Q50) and 75 µmol... (Complete abstract click electronic access below) / Mestre

Antioxidant compounds were extracted from canola meal by subcritical water extraction (SWE), hot water (80°C) extraction and ethanolic (95%) extraction. The highest extract yields were obtained with SWE at 160°C, and the lowest with ethanolic extraction (SWE 160°C > SWE sequential > SWE 135°C > SWE 110°C = hot water extraction > ethanolic extraction). Ethanolic extracts exhibited the highest total phenolics contents and Trolox equivalent antioxidant capacity (TEAC) values on a per gram of extract basis, and hot water extracts, the lowest (ethanolic extraction > SWE 110°C > SWE 160°C > hot water extraction). Extraction pressure (3.44-6.89 MPa) had no effect on the yields, total phenolics contents or TEAC values of extracts from SWE. The use of buffered water (pH 2-8) for SWE increased extract yield but had adverse effects on the total phenolics contents and TEAC values of extracts. No increase in efficacy of SWE at 110 or 160°C was observed at extraction times longer than 25-30 min. The total phenolics contents and antioxidant capacities of extracts were assessed by the total phenolics assay, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method, TEAC method, the β-carotene-linoleic acid (linoleate) model system, the reducing power assay and the stripped oil model system. Ethanolic extracts exhibited the highest total phenolic contents and antioxidant capacities on a per gram of extract basis. Subcritical water extraction at 160°C exhibited the highest total phenolic contents and antioxidant capacities on a per gram of meal basis. Results from the total phenolics assay and the antioxidant capacity assays were significantly correlated, with the exception of those from the stripped oil model system.

Synthesis of size tunable nanomaterials creates distinct chemo-physical properties. Recently, the popularity of magnetic iron oxide and cerium oxide (CeO2) nanocrystals enables researchers to use magnetic iron oxides (magnetite and ferrites) in size dependent magnetic separation and CeO2 as an automobile exhaust gas catalyst. This research shows production of diameter-controlled monodisperse magnetic iron oxide (ranging from 3 to 40 nm in diameter) and CeO2 (from 3 to 10 nm in diameter) nanocrystals with exceptional narrow diameter distribution (σ<10%). The morphology and composition of the nanocrystals were varied by use of diverse metal precursors, reaction temperature, time, cosurfactants, and molar ratio between metal salt and surfactant. Now the narrow diameter distributions of preformed magnetic iron oxide nanocrystals made it possible to grow diameter controlled uniform CNTs. The correlation between aluminum ferrite nanocrystal diameter and CNT diameter was nearly one. Additionally, we could synthesize the highest percentage (60%) of single walled CNTs from the smallest aluminum ferrite nanocrystals (4.0 nm). Because of the synthesis of uniform nanocrystalline CeO2, we could study diameter dependent antioxidant properties of nanocrystalline CeO2; antioxidant capacity of CeO2 was nine times higher than a known commercial standard antioxidant, Trolox. In addition, the smallest CeO2 nanocrystal (4 nm) decreased the oxidative stress of human dermal fibroblasts (HDF) exposed to hydrogen peroxide. These works suggest better understanding of monodisperse nanocrystal synthetic mechanism and potential uses of the materials, such as high quality CNT growth using magnetic iron oxides as precursor catalysts and the reduction of oxidative stress in cells using monodisperse CeO2 nanocrystal as an antioxidant for reactive oxygen species in biological media.

Antioxidant compounds were extracted from canola meal by subcritical water extraction (SWE), hot water (80°C) extraction and ethanolic (95%) extraction. The highest extract yields were obtained with SWE at 160°C, and the lowest with ethanolic extraction (SWE 160°C > SWE sequential > SWE 135°C > SWE 110°C = hot water extraction > ethanolic extraction). Ethanolic extracts exhibited the highest total phenolics contents and Trolox equivalent antioxidant capacity (TEAC) values on a per gram of extract basis, and hot water extracts, the lowest (ethanolic extraction > SWE 110°C > SWE 160°C > hot water extraction). Extraction pressure (3.44-6.89 MPa) had no effect on the yields, total phenolics contents or TEAC values of extracts from SWE. The use of buffered water (pH 2-8) for SWE increased extract yield but had adverse effects on the total phenolics contents and TEAC values of extracts. No increase in efficacy of SWE at 110 or 160°C was observed at extraction times longer than 25-30 min. The total phenolics contents and antioxidant capacities of extracts were assessed by the total phenolics assay, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging method, TEAC method, the β-carotene-linoleic acid (linoleate) model system, the reducing power assay and the stripped oil model system. Ethanolic extracts exhibited the highest total phenolic contents and antioxidant capacities on a per gram of extract basis. Subcritical water extraction at 160°C exhibited the highest total phenolic contents and antioxidant capacities on a per gram of meal basis. Results from the total phenolics assay and the antioxidant capacity assays were significantly correlated, with the exception of those from the stripped oil model system.

Antioxidant properties of sorghum are related to sorghum type and method of processing into foods. Tannin and non-tannin sorghums and their products were evaluated for total phenols, tannins and antioxidant activity. Total phenols were determined using the Folin Ciocalteu method, and tannins were determined by the vanillin-HCl method. Antioxidant activity was evaluated using the ABTS (2,2¢- azinobis(3-ethyl-benzothiazoline-6-sulphonic acid) and DPPH (2,2¢-diphenyl-Ipicrylhydrazyl) assays. Tannin sorghums and their products had higher total phenols, tannins and antioxidant activity than non-tannin sorghum grain and products. Fermentation, extrusion cooking and porridge making reduced measurable phenols, tannins and in vitro antioxidant activity. Reduction was probably due to phenols binding to the food components, thus reducing their solubility in the extracting solvents; 1% HCl in methanol and 70% aqueous acetone. The procyanidin profile obtained using normal phase HPLC and fluorescent detection showed that extrusion cooking and porridge making lowered extractability of polymers (DP>8), while that of oligomers (DP 2-8) and monomers in porridges was not significantly changed. This indicated increased interactions of procyanidin polymers with the food matrix, especially with protein. Pepsin treatment of sorghum extrudates and porridges significantly improved the antioxidant activity and recovery. The highest antioxidant activity was in the supernatants of pepsin hydrolysates. Amylase treatment alone did not significantly affect phenol content and antioxidants, except in bread containing non-tannin white sorghum bran, where there was a slight increase in phenols. The combination of pepsin followed by amylase treatment of porridges and extrudates had effects similar to those of pepsin alone. Improved extractability of antioxidants on pepsin treatment was due to either the release of phenolic antioxidants or protein hydrolysates high in aromatic amino acid residues such as tyrosine, also known for their antioxidant activity. In either situation the improved antioxidant activity could mean that once food is digested it can potentially protect the gastrointestinal tract against oxidative stress generated from the diet and that produced by food interactions during digestion. There is scope to explore other biological methods like use of other proteases to improve antioxidant recovery. Further work would thus determine contribution of phenolic compounds to improved antioxidant activity, and also identify the phenolics.

Antioxidant activity of dried plum powder (DPP) at 3% was compared to rosemary extract (RE) at 0.05% in turkey breakfast sausages which were stored under three aerobic conditions: raw refrigerated (RR; 6 degrees C), raw and precooked frozen (RF and PF, respectively; -23 degrees C). Sausage links were tested on specific days over a 56 day shelf-life. Analyses included pH, proximate composition, objective color (CIE L*, a*,b*), lipid oxidation (TBARS), aerobic plate count and enumeration of lactic acid bacteria, sensory, reheat yields and shear force. All RR treatments surpassed the threshold of 3 for TBARS by day 6. Spoilage occurred by day 3 for all RR treatments (> 6.0 log10). Treatments containing DPP had lower TBARS values for RF (P < 0.05) and PF (P &lt; 0.01). DPP containing treatments had lower external and internal L* values and a* values while internal b* values were higher. Sensory scores for plum and sweet were higher, while cardboard and rancidity were lower in treatments containing DPP. Sensory scores for cardboard and rancidity were lower for RF and higher for PF treatments. Reheated cooked yields and shear force values for PF treatments held either 15 or 30 min showed an increasing trend with subsequent storage. Proximate composition data showed no significant differences for fat, moisture, and protein. DPP containing treatments were different from other treatments having a lower pH except for the PF RE treatment. The addition of DPP at 3% into a turkey breakfast sausage had an inhibitory effect on lipid oxidation in a RF and PF treatments. Inclusion of DPP darkened the external and internal appearance and increased yellowness as well as increasing the sweetness and plum flavor.