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Graphical abstract Highlights • Design and synthesis of an efficient anti-oxidant lipid for gene delivery. • Hybrid of two natural anti-oxidants. • Two and half fold better potent than the commercial lipid lipofectamine 2000 in delivering pDNA. • Least cytotoxic especially neuro cell lines. • Serum compatible. • Can be exploited as a delivering system for treating ROS related diseases such as malignancy, brain stroke etc. Abstract Natural antioxidants and vitamins have potential to protect biological systems from peroxidative damage induced by peroxyl radicals, α-tocopherol (Vitamin E, lipid soluble) and ascorbic acid (vitamin C, water soluble), well known natural antioxidant molecules. In the present study we described the synthesis and biological evaluation of hybrid of these two natural antioxidants with each other via ammonium di-ethylether linker, Toc-As in gene delivery. Two control cationic lipids N14-As and Toc-NOH are designed in such a way that one is with ascorbic acid moiety and no tocopherol moiety; another is with tocopherol moiety and no ascorbic acid moiety respectively. All the three cationic lipids can form self-assembled aggregates. The antioxidant efficiencies of the three lipids were compared with free ascorbic acid. The cationic lipids (Toc-As , N14-As and Toc-NOH) were formulated individually with a well-known fusogenic co-lipid DOPE and characterization studies such as DNA binding, heparin displacement, size, charge, circular dichroism were performed. The biological characterization studies such as cell viability assay and in vitro transfection studies were carried out with the above formulations in HepG2, Neuro-2a, CHO andHEK-293T cell lines. The three formulations showed their transfection efficiencies with highest in Toc-As , moderate in N14-As and least in Toc-NOH. Interestingly, the transfection efficiency observed with the antioxidant based conjugated lipid Toc-As is found to be approximately two and half fold higher than the commercially available lipofectamine 2000 at 4:1 charge ratio in Hep G2 cell lines. In the other cell lines studied the efficiency of Toc-As is found to be either higher or similarly active compared to lipofectamine 2000. The physicochemical characterization results show that Toc-As lipid is showing maximum antioxidant potency, strong binding with pDNA, least size and optimal zeta potential. It is also found to be least toxic in all the cell lines studied especially in Neuro-2a cell lines when compared to other two lipids. In summary, the designed antioxidant lipid can be exploited as a delivering system for treating ROS related diseases such as malignancy, brain stroke, etc. [ABSTRACT FROM AUTHOR]

As a highly potent reactive oxygen and nitrogen species, peroxynitrite (PON) has endogenous production in the eye ball and contributes to a variety of ocular disorders. In the current study the structural characteristics, chaperone-like activity and conformational stability of R54C mutant αA-crystallin (αA-Cry) were studied upon modification with PON and in the presence of three antioxidant compounds such as ascorbic acid (ASA), glutathione (GSH) and N -acetylcysteine (NAC) using gel electrophoresis and different spectroscopy methods. The results of both fluorescence analysis and gel electrophoresis suggested that PON modification leads to dityrosine-mediated intermolecular cross-linking of this cataractogenic mutant protein. Also, the propensity of R54C mutant αA-Cry for disulfide cross-linking was increased upon PON modification. In addition, the PON-modified protein indicated structural alteration, reduced chemical stability and different pattern of proteolysis. Upon modification with PON, mutant αA-Cry displayed a significant increase in the chaperone-like activity against aggregation of γ-crystallin and insulin. In addition, different antioxidant compounds indicated a prominent role in neutralizing the PON damaging effects on structural integrity and stability of this protein. The results of this study may highlight the importance of antioxidant-rich foods or potent antioxidant supplements in protection of lens crystallins against PON-mediated structural damages and cataract development. [ABSTRACT FROM AUTHOR]

Abstract: Ascorbic acid (AA) is a common culture medium and dietary supplement. While AA is most commonly known for its antioxidant properties, it is also known to function as a pro-oxidant under select conditions. However, the complexity and often unknown composition of biological culture systems makes prediction of AA behaviour in supplemented cultures challenging. The frequent observation of outcomes inconsistent with antioxidant behaviour suggests that AA may be playing a pro-oxidant role more often than appreciated. In this work we explored the intracellular and extracellular impact of AA supplementation on KG1a myeloid leukaemia cells over a 24-h culture period following the addition of the AA supplement. At 24h we found that supplementation of AA up to 250μM resulted in intracellular antioxidant behaviour. However, when these same cultures were evaluated at 2 or 4h we observed pro-oxidant activity at the higher AA concentrations indicating that the outcome was very much time and dose dependent. In contrast, pro-oxidant activity was never observed in the extracellular medium. Paradoxically, and to our knowledge not previously reported, we observed that intracellular pro-oxidant activity and extracellular antioxidant activity could occur simultaneously. These results indicate that the precise activity of AA supplementation varies as a function of dose, time and cellular location. Further, these results demonstrate how in the absence of careful culture characterization the true impact of AA on cultures could be underappreciated. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to facilitate development of natural antioxidants from defatted peanut kernels. Protein hydrolysates obtained from defatted peanut kernels with esperase treatment for 2h exhibited higher antioxidative activity toward linolenic acid peroxidation than other proteases (including neutrase, pepsin, protease A and protease N). The esperase hydrolysate of peanut protein (EHPP) was further separated with 3 and 5kDa molecular cut-off membranes to determine the influence of molecular weight. EHPP with molecular weight 3∼5kDa showed higher relative antioxidative activity, DPPH radical scavenging activity and metal chelating activity than that with molecular weight lower than 3kDa or higher than 5kDa. The fraction was further purified by ion exchange chromatography and high-performance liquid chromatography; the final peanut peptides exhibited higher relative antioxidative activity (27.5) than ascorbic acid (9.5). This study reported for the first time that protein hydrolysates from defatted peanut kernels possess antioxidative activity. [Copyright &y& Elsevier]

Abstract: “Early” potato is a typical crop grown in most of the Mediterranean countries, and it is one of the most important horticultural crops exported towards the Northern European markets. In order to improve market value of early potatoes, growers are more and more involved in choosing new potato varieties and constantly looking for methods to improve the commercial quality of tubers. One of the most increasingly used agro-techniques is chemical haulm desiccation, which aims to simplify harvesting and can help to manipulate tuber size distribution and tuber skin-set. Its effect on yield and quality aspects of early potato remains to be better evaluated. This paper resumes results of trials and analysis conducted during 2007 concerning the effect of the application of a chemical desiccant (gluphosinate ammonium) on some relevant nutritional parameters of three early potato varieties (Spunta, Ditta, and Krone) grown in Southern Italy. Tubers from the trials were analyzed for tuber size distribution, flesh and skin colour, dry matter, nitrate, soluble carbohydrates, total and resistant starch, vitamin C, phenol content, and total antioxidant activity. Results indicate that chemical desiccation does not affect the levels of vitamin C and those of other molecules with antioxidant properties as well as those of total soluble carbohydrates. On the other hand, it induces a significant decrease in starch storage and an increase in the percentage of resistant starch (a component of dietary fibre). [Copyright &y& Elsevier]

Abstract: Ether, methanolic and aqueous extracts of lyophilized rambutan (Nephelium lappaceum L.) peels and seeds were evaluated for phenolic contents, antioxidant and antibacterial activities. High amounts of phenolic compounds were found in the peel extracts and the highest content was in the methanolic fraction (542.2mg/g dry extract). Several potential antioxidant activities, including reducing power, β-carotene bleaching, linoleic peroxidation and free radical scavenging activity, were evaluated. The peel extracts exhibited higher antioxidant activity than the seed extracts in all methods determined (P <0.05). The methanolic fraction was found to be the most active antioxidant as shown by their 50% DPPH inhibition concentration, 4.94μg/mL. The results indicated this fraction exhibited greater DPPH radical scavenging activity than BHT and ascorbic acid (0.32g dry extract/g BHT or ascorbic acid). Antibacterial activity against eight bacterial strains was assessed by disc diffusion and broth macrodilution methods. All peel extracts exhibited antibacterial activity against five pathogenic bacteria. The most sensitive strain, Staphylococcus epidermidis, was inhibited by the methanolic extract (MIC 2.0mg/mL). [Copyright &y& Elsevier]

As a powerful natural antioxidant, lipoic acid exerts significant antioxidant activities in vivo and in vitro by deactivation of reactive oxygen and nitrogen species. In this study we present a novel synergistic interaction of lipoic acid with other endogenous or exogenous antioxidants. Antioxidants vitamins C and E analogue (Trolox C) and hydroxycinnamic acid derivatives were found to recycle lipoic acid by donating electrons to lipoic acid radical cations, thereby increasing the antioxidant capacity of lipoic acid in vivo and in vitro. The rate constant of the electron transfer is in the order 109 dm3 mol−1 s−1, close to the diffusion-controlled limit, and transfer quantum yield is above 95%. [Copyright &y& Elsevier]