花生壳中生物抗氧剂及其抗自由基活性研究

用不同方法从花生壳中提取分离了黄酮类化合物 。

生物基抗氧剂在绿色化工中应用与发展

高分子材料向绿色、环保方向发展是当前行业热点与趋势,生物基抗氧剂是助推高分子材料行业绿色、健康、安全、环保化的升级产品,本文介绍了生物基抗氧剂的概念、原料、应用及研究进展。

湖北绿茶中两种新的没食子酸类衍生物的结构鉴定

用 2DNMR技术研究了从绿茶中分离得到的 2种新的没食子酸类衍生物 ,对其1 H和1

抗氧剂现状及发展

抗氧剂是一种纯化合物或是几种纯化合物的混合物，其作用在于减缓塑料橡胶以及其他高分子材料的自氧化反应速度，保证在成型、贮存过程中不影响其使用寿命。抗氧剂除了在塑料橡胶中使用以外，也广泛应用在电石、油脂及食品工业，以防止燃油。

Antioxidant enzyme activities in different genders and tissues of amphioxus Branchiostoma belcheri tsingtauense

Information regarding antioxidant enzymes in amphioxus remains lacking, and this study was carried out to examine the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in different genders and tissues of amphioxus Branchiostoma belcheri tsingtauense. Results show that (1) CuZn-SOD, CAT and GPX activities in the whole amphioxus B. belcheri tsing- tauense were basically at the same levels in male and female amphioxus, whereas both T-SOD and Mn-SOD activities in male amphioxus were significantly higher than that in the female (P<0.05); (2) The testis had significantly higher T-SOD and CuZn-SOD activities than the ovary (P<0.05); (3) CuZn-SOD activity was undetectable in the guts of male and female amphioxus; (4) For both male and female am- phioxus, the activities of CAT and GPX in the gonads including testis and ovary were the lowest (P<0.05) among the tissues examined; (5) The gut and gill had the same level GPX activities while the gut had a higher CAT activity; (6) There was no clear difference in CAT and GPX activities in the corresponding tissues between male and female amphioxus. The study on SOD, CAT and GPX activities in different genders and tissues of the protochordate provides data for future comparison of amphioxus antioxidant enzymes with those of invertebrates and vertebrates.

DFT-Study on Antioxydant of 3-Alkyl-4-P henylacetylam i no-1H-1,2,4-Triazol-5-O nes and Its Derivatives

In this article, we have performed B3LYP/6-31＋G（d） calculations of geometrical and reaction enthalpies of antioxidant mechanisms for ADPHT 1-4 （3-alkyl-4-phenylacetylamino-lH-1,2,4-triazol-5-ones） and its derivatives： HAT （hydrogen atom transfer）, SET-PT （single electron transfer-proton transfer） and SPLET （sequential proton-loss electron transfer） were investigated in gas and solution-phases. Solvent contribution to enthalpies was computed employing integral equation formalism IEF-PCM （integral equation formalism method） method. It turned out that the lowest BDEs （bond dissociation energies） is obtained for C-H bonds due to captodative effect in various media. Results indicate that HAT mechanism represents the most anticipated process in gas-phase from thermodynamic point of view. But, the SPLET represents the thermodynamically preferred reaction pathway in solvents （2-propanol, acetonitrile, DMF （N,N-dimethylformamide） and water）. The authors showed that bond dissociation energies, IP （ionization potential） and PA （proton affinity） are sufficient to evaluate the thermodynamically preferred mechanism.

Synthesis of the dl-ξ-Thiotocopherol： Newest Derivative of the dl-a-Tocopherol

Tocopherol is the most active vitamin and natural antioxidant existing in the nature known as vitamin E. Lacking of this vitamin makes drastic exchanges on the health of the living organisms. Their active chemical form is l-α-tocopherol substance. In this article, α-thiotocopherol a tocopherol derivative was synthesized via a precursor like dl-α-tocopherol, which has better antioxidant than natural α-tocopherol. And the last compound after separation and purification via TLC and PC procedures was analyzed by FTIR, GC-MS and elemental analysis, oxidative stability is tested with TGA method in air showing roughly antioxidant effect. Another approach is measurment of redox potential against a reference electrode under inert nitrogen atmosphere.

Lasertherapy as A Strategy for Treatment Healing under Caloric Restriction – Study in Rats

Complications in the healing process are challenging, especially in clinical situations of caloric restriction （CR）. The lasertherapy becomes an important strategy that aids the repair, especially in CR. Thus, it is important to investigate the InGaAlP-660 nm laser as an strategy to repair cutaneous wounds in rats submitted to 30% of CR and to understand the tissue repair in clinical situations of CR. Thirty-six male Wistar rats were used, of which half were fed with 30% less ration, and half with ad libitum diet, for 21 days. Then, punch lesions of 1.5 cm in diameter were made on the animals backs, which were divided into： NR （no-restricted）, R （restricted）-both before lesion; C （control）, RC （restricted-control）, L （laser）, RL （restricted-laser）-after lesion. Samples of the skin/lesion/scar were collected on the 2nd, 7th and 14th days post-injury for histological, biochemical and molecular analyses. The R group showed reduction of body mass, epidermal/dermal thickness, inflammation, angiogenesis, fibroplasia and collagenesis. The RL group showed control of inflammation, oxidative damage and increase of antioxidants than RC, which probably favored angiogenesis, collagenesis and reepithelialization, similar to C and L. Thus, 30% of CR impaired the skin （before lesion）. In the lesion, lasertherapy has shown to be effective in tissue repair mainly in CR status, being thus, the laser clinically important strategy to tissue repair in critical situations of caloric restriction.

Chemical and Biological Characterization from Condafia microphylla Fruits, a Native Species of Patagonia Argentina

Condalia microphylla Cav. （Rhamnaceae）, popularly known as ＂piquillin＂, is widely distributed in Patagonia. The drupes are consumed as fresh fruits by Argentine communities. The aim of this work was to quantify the nutritional value of C. microphylla fruit and the phenolic compounds present and to determine the functional antioxidant properties in vitro and in vivo. The nutritional value was determined according to the Association of Official Analytical Chemists （AOAC） methodology, and phenolic compounds were quantified by diode-array detection （HPLC-DAD）. Antioxidant activity in vitro and in vivo was analyzed through the use of the radical species 2,2-diphenyl-l-picrylhydrazyl （DPPH） and zebrafish model, respectively. Quercetin-3-O-rutinoside （rutin） was the single principal phenolic compound. The extracts contained in vitro antioxidant activities and total phenolic contents （TPCs） between 1,143 ~ 112 lag and 4,633 ~ 174 lag gallic-acid equivalents （GAEs） per 100 g dry weight （DW）, though no relationship was found between the latter parameter and the antioxidant activity of the extracts. When zebrafish larvae were exposed to oxidative stress （2.4% v/v H2O2）, a concentration as low as 1.44 lag of GAEs/mL of piquillin-derived polyphenols inhibited lipid oxidation by up to 40%. Thus, in view of these advantageous functional food properties and the opportunity to exploit this Patagonian natural resource, piquillin consumption should be promoted worldwide.

Evaluation of the antioxidant effects of four main theaflavin derivatives through chemiluminescence and DNA damage analyses

Theaflavins(TFs) are the dimers of a couple of epimerized catechins,which are specially formed during black tea fermentation.To explore the differences among four main TF derivatives(theaflavin(TF 1),theaflavin3-gallate(TF 2 A),theaflavin-3'-gallate(TF 2 B),and theaflavin-3,3'-digallate(TF 3)) in scavenging reactive oxygen species(ROS) in vitro,their properties of inhibiting superoxide,singlet oxygen,hydrogen peroxide,and the hydroxyl radical,and their effects on hydroxyl radical-induced DNA oxidative damage were systematically analyzed in the present study.The results show that,compared with()-epigallocatechin gallate(EGCG),TF derivatives were good antioxidants for scavenging ROS and preventing the hydroxyl radical-induced DNA damage in vitro.TF 3 was the most positive in scavenging hydrogen peroxide and hydroxyl radical,and TF 1 suppressed superoxide.Positive antioxidant capacities of TF 2 B on singlet oxygen,hydrogen peroxide,hydroxyl radical,and the hydroxyl radical-induced DNA damage in vitro were found.The differences between the antioxidant capacities of four main TF derivatives in relation to their chemical structures were also discussed.We suggest that these activity differences among TF derivatives would be beneficial to scavenge different ROS with therapeutic potential.

Synthesis and biological evaluation of 8-substituted and deglucuronidated scutellarin and baicalin analogues as antioxidant responsive element activators

Flavonoids are important bioactive dietary compounds, which are proved to be antioxidant responsive element (ARE) activators to defend against electrophilic toxicants and oxidative stress. The activators induce ARE gene transcription through Nrf2 factor, a major transcriptional stimulator of cytoprotective genes, relieved from a Keap1 complex. In this report, based on the structures of two flavonoids, scutellarin and baicalin, which are extracted from two common Chinese plants Dengzhanhua (Erigeron breviscapus (vant) Hand-Mazz) and Huangqin (Scutellaria baicalensis Georigi), respectively, we synthesized several 8-substituted and deglucuronidated analogues and identified the ARE activation effects of these flavonoids. We found that the Baicalin, deglucurnonidated Baicalin and diaza cyclopenta derivative were more active. Their dose-dependent upregulation activities of ARE and NQO1 and induction effects of Nrf2 were testified. The results presented that these three analogues had good upregulation effects on ARE, and they could be potentially utilized in relieving oxidative stress, upon further neuroprotective tests.

Endophytes from medicinal plants and their potential for producing indole acetic acid, improving seed germination and mitigating oxidative stress

Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants（Caralluma acutangula, Rhazya stricta, and Moringa peregrina） and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp.（6 isolates）, Alternaria sp.（2）, Bipolaris sp.（1）, and Cladosporium sp.（1） based on 18 S rD NA sequencing and phylogenetic analysis. The culture filtrates（CFs; 25%, 50%, and 100% concentrations） from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF（100%） of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry（GC/MS） analysis showed the highest indole acetic acid content（（54.31±0.21） μmol/L） in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.

Yolk vitamin E positively affects prenatal growth but not oxidative status in yellow-legged gull embryos

Parental effects occur whenever the phenotype of parents or the environment that they experience influences the phenotype and fitness of their offspring, In birds, parental effects are often mediated by the size and biochemical quality of the eggs in terms of maternally transferred components. Exogenous antioxidants are key egg components that accomplish crucial physiological functions during early life. Among these, vitamin E plays a vital role during prenatal development when the intense metabolism accompanying rapid embryo growth results in overproduction of pro-oxidant molecules. Studies of captive birds have demonstrated the positive effect of vitamin E supplementation on diverse phenotypic traits of hatchling and adult individuals, but its effects on embryo phenotype has never been investigated neither in captivity nor under a natural selection regime. In the present study, we experimentally tested the effect of the in ovo supplementation of vitamin E on morphological traits and oxidative status of yellow-legged gull （Larus michahellis） embryos. The supplementation of vitamin E promoted somatic growth in embryos soon before hatching, but did not affect their oxidative status. Our results suggest that maternally transferred vitamin E concentrations are optimized to prevent imbalances of oxidative status and the consequent raise of oxidative damage in yellow-legged gull embryos during prenatal development.