鹅掌柴提取物的抗氧化活性

从清除超氧阴离子自由基(O-2)、还原力、清除DPPH自由基、清除羟基自由基(·OH)等方面,研究鹅掌柴提取物的抗氧化活性.结果表明:鹅掌柴提取物对DPPH自由基和羟基自由基的清除能力较强,清除率分别为78.57%和74.99%,对脂质体过氧化的的抑制率为21.41%;与VE、VC、BHT相比,鹅掌柴提取物的还原能力和对Fe2+的络合能力也较强;但对超氧阴离子自由基的清除能力较弱.因此.鹅掌柴提取物是一种抗氧化功效较强的活性物质,具有很好的保健功能.     

大豆异黄酮的抗氧化和抗肿瘤活性研究

采用邻苯三酚自氧化法和Fenton法,检测大豆异黄酮的抗超氧自由基和羟基自由基的活性,通过MTT比色法检测大豆异黄酮对大鼠肝癌CBRH-7919细胞和小鼠白血病CML-K562细胞增殖的影响来研究大豆异黄酮的抗氧化和抗肿瘤活性.结果表明:大豆异黄酮具有显著的抗氧化和抗肿瘤活性.其中大豆异黄酮对超氧自由基的清除率达到50%时所需要的用量(IC50)为0.14 mg·mL-1;对羟基自由基的清除率达到50%时所需要的用量(IC50)为0.57 mg·mL-1;大豆异黄酮对CBRH-7919细胞生长抑制率达到50%时所需要的用量(IC50)为 7.55 mg·L-1;对CML-K562细胞生长抑制率达到50%时所需要的用量(IC50)为10.35 mg·L-1.大豆异黄酮具有显著的抗氧化和抗肿瘤活性.     

红厚壳种仁油脂体外抗氧化能力研究

采用4个抗氧化体系对红厚壳种仁油脂的体外抗氧化能力进行研究。结果表明,红厚壳种仁油脂总酚酸含量为(0.26±0.045)mg/mL。0.10%的红厚壳种仁油脂对ABTS+自由基清除能力的TEAC值为123.39μmol/L;5%的红厚壳种仁油脂清除DPPH自由基的能力显著高于100μg/mL的BHT;7.5%的清除羟自由基的能力显著高于100μg/mL的BHT和Trolox;1.6%的对脂质过氧化的抑制能力均不及100μg/mL的BHT和Trolox。说明红厚壳种仁油脂具有显著的抗氧化活性。     

椰肉中醇溶蛋白抗氧化活性

从脂质过氧化的抑制作用、对DPPH自由基(DPPH.)的清除作用、羟基自由基(·0H)的清除作用、Fe2+的络合能力等几个方面研究椰子醇溶蛋白的抗氧化活性,并以BHT、没食子酸,VE做为对照.结果表明,椰子醇溶蛋白对Fe2+具有很强的络合能力.对DPPH·有较强的清除能力,同时具有一定的清除·OH能力和还原能力,但其抑制脂质体过氧化作用的能力较弱.这表明椰子醇溶蛋白有较好的抗氧化活性,但其溶解性限制了其在脂溶性食品中的应用.     

树舌胞外富锌多糖体外抗氧化活性研究

利用树舌的深层发酵法获得胞外富锌多糖,从抗油脂过氧化、抑制羟自由基的产生、清除DPPH·和O2·- 4个方面,探讨树舌胞外富锌多糖抗氧化活性。结果表明：树舌富锌培养基内ZnSO4浓度在200 μg/mL时,可以显著提高胞外多糖的有机锌含量,使有机锌含量达0.67 mg/g,比对照组提高252％。有机锌对提高胞外多糖抗氧化能力有显著的效果,在多糖浓度为2.5 g/L,对油脂过氧化的抑制、清除羟自由基、DPPH·和O2·- 的能力分别比对照提高12.5％、26.83％、30％ 和20％。胞外富锌多糖抗氧化活性     

Radical Scavenging Activity of the Extraction with 50％ Ethanol from Epicarp of WenYe Ⅱ Coconut

从清除超氧阴离子自由基、还原力、清除DPPH自由基、清除羟基自由基等方面,研究“文椰2号”椰子外果皮中50％乙醇提取物的抗氧化性.结果表明,“文椰2号”椰子外果皮中50％乙醇提取物的还原能力较强,对DPPH.自由基和羟基自由基有较强的清除能力,对Fe2+的络合能力和脂质体过氧化反应的抑制作用也较强,但对超氧阴离子自由基的清除能力较弱.因此,椰子外果皮中50％乙醇提取物是一种抗氧化功效较强的活性物质,具有很好的保健功能.     

大豆荚壳异黄酮制备与体外抗氧化性研究

研究大豆荚壳异黄酮(Isoflavones from soybean hull,ISH)制备与体外抗氧化性作用.通过超声回流法提取和大孔吸附树脂纯化,得到纯化的ISH.以VC、BHT、芦丁和槲皮素为阳性对照,测定了 ISH的还原力;对羟基自由基、超氧阴离子自由基、烷基自由基的清除率以及抑制油脂过氧化的能力.结果表明:ISH的还原力高于BHT和VC,ISH对这几种自由基均有一定的清除作用,ISH的添加量在试验范围内与其抗氧化活性呈正相关.当试验量大于5μg·mL-1时,ISH的抗氧化性能均优于VC、BHT、芦丁和槲皮素.     

“文椰2号”椰子外果皮中50％乙醇提取物体外清除自由基能力的研究

从清除超氧阴离子自由基、还原力、清除DPPH自由基、清除羟基自由基等方面,研究“文椰2号”椰子外果皮中50％乙醇提取物的抗氧化性。结果表明,“文椰2号”椰子外果皮中50％乙醇提取物的还原能力较强,对DPPH·自由基和羟基自由基有较强的清除能力,对Fe2+的络合能力和脂质体过氧化反应的抑制作用也较强,但对超氧阴离子自由基的清除能力较弱。因此,椰子外果皮中50％乙醇提取物是一种抗氧化功效较强的活性物质,具有很好的保健功能。     

胡萝卜多糖体外抗氧化活性研究

采用热水浸提法从胡萝卜中提取胡萝卜多糖,通过测定胡萝卜多糖对超氧阴离子自由基(O-2.)、羟基自由基(.OH)、DPPH自由基的清除能力以及对卵黄脂蛋白脂质过氧化的抑制作用,研究其体外抗氧化活性。结果表明,胡萝卜多糖对.OH、O-2.、DPPH自由基具有较强的清除能力,对卵黄脂蛋白脂质过氧化具有一定的抑制作用,因此胡萝卜多糖具有良好的体外抗氧化活性。     

精炼糖厂离交洗脱液色素对食用猪油的抗氧化作用研究

精炼糖厂离子交换树脂再生洗脱液中主要是一些没有被树脂利用的再生剂(氯化钠和氢氧化钠)及被洗脱出来的糖浆原来的有色物质。为探讨离交洗脱液色素清除自由基、抑制油脂的脂质过氧化反应等体外抗氧化活性,测定了离交洗脱液色素的总黄酮和总多酚含量,并采用1,1-二苯基-2-三硝基苯肼(DPPH·)、[2,2′-连氨-(3-乙基苯并噻唑林-6-磺酸)二氨盐]自由基(ABTS+·)测定法,评价离交洗脱液色素的DPPH·自由基、ABTS+·自由基清除能力;以猪油为底物,以过氧化值(POV值)、酸价为指标,研究了离交洗脱液色素对油脂的抗氧化性能以及对猪油氧化的抑制作用,并与茶多酚和抗坏血酸(VC)进行比较。结果表明,离交洗脱液色素对DPPH·自由基、ABTS+·自由基有较好的清除效果;猪油中添加离交洗脱液色素后,对油脂也表现出较强的抗氧化作用,可明显地抑制猪油POV值和酸价的升高。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Mineral composition of some traditional Mexican teas

Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

In vitro antimicrobial activity of different accessions ofSolanum commersonii Dun. from Uruguay

Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds.     

Extreme resistance to infection by potato virus X in genotypes of wild tuber-bearingSolanum species

Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta. Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X¹ (also called RX_act).     

Cyanobacteria Secondary Metabolites as Biotechnological Ingredients in Natural Anti-Aging Cosmetics: Potential to Overcome Hyperpigmentation,Loss of Skin Density and UV Radiation-Deleterious Effects

The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O₂^•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O₂^•− scavenging, (IC₅₀ = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC₂₅ = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC₅₀ = 863 µg/mL; elastase, IC₅₀ = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O₂^•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms.     

Marine Pharmacology in 2009–2011: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis,and Antiviral Activities; Affecting the Immune and Nervous Systems,and other Miscellaneous Mechanisms of Action ?

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories.