Targeted metabolite analysis and antioxidant potential of Rumex induratus     

Guerra L  Pereira C  Andrade PB  Rodrigues MA  Ferreres F  De Pinho PG  Seabra RM  Valentão P 《Journal of agricultural and food chemistry》2008,56(17):8184-8194

Targeted metabolite analysis of aqueous extract of Rumex induratus leaves, in terms of phenolic compounds and organic acids, and the study of its antioxidant activity against the DPPH(*) radical, a reactive oxygen species, hypochlorous acid, and a reactive nitrogen species, nitric oxide ((*)NO), were performed. The samples were collected in several locations, spontaneously occurring or from greenhouse culture, at different stages of development and seasons. The phenolic composition was achieved by high-performance liquid chromatography (HPLC)-diode array detection, and four hydroxycinnamic acid derivatives and 10 flavonoid glycosides (C- and O-heterosides) were determined. Organic acids composition was established by HPLC-UV, revealing five compounds. The total amount of phenolic compounds and organic acids were affected by growing conditions and developmental phase. The aqueous extract exhibited a dose-related activity against all tested reactive species.  相似文献   

Sub‐lethal effects of abamectin suppressing colonies of the leaf‐cutting ant Acromyrmex subterraneus subterraneus     

Eduardo C Antunes  Raul Narciso C Guedes  Terezinha Maria C Della Lucia  Jos E Serro 《Pest management science》2000,56(12):1059-1064

An assessment of the sub‐lethal effects of abamectin on queens of the leaf‐cutting ant Acromyrmex subterraneus subterraneus (Hymenoptera: Formicidae) was carried out. A concentration‐response bioassay was conducted by exposing media workers (head capsule width ranging from 1.69 to 1.83 mm) to filter paper impregnated with abamectin residue. This bioassay allowed selection of the abamectin concentrations (0, 10, 50 and 100 mg AI ml⁻¹) to be used in the experiment in which eight queens were exposed to the insecticide. The highest concentration killed queens, but those exposed to lower concentrations survived and were placed back in their nests. Reductions in leaf consumption, fungus garden volume, and foraging activity were observed in colonies whose queens were exposed to higher abamectin concentration (50 mg AI ml⁻¹). Colonies with queens exposed to 50 mg AI ml⁻¹ were suppressed after 11 weeks. The dissection of queen ovaries revealed a marked decrease in the number of ovarioles per ovary and oocytes per ovariole with increased insecticide concentration. It would appear that, as abamectin‐exposed queens became reproductively impaired, producing little or no progeny, colony members were not replaced and this led to colony suppression. © 2000 Society of Chemical Industry  相似文献   

Pesticides and passive dispersal: acaricide‐ and starvation‐induced take‐off of the predatory mite Neoseiulus baraki          下载免费PDF全文

Vaneska Barbosa Monteiro  Vanessa Farias Silva  Debora Barbosa Lima  Raul Narciso Carvalho Guedes  Manoel Guedes Correa Gondim Jr 《Pest management science》2018,74(6):1272-1278

  相似文献   

Self -Compatibility in a Diploid Hybrid Population of <Emphasis Type="Italic">Solanum phureja</Emphasis> – <Emphasis Type="Italic">S. stenotomum</Emphasis>     

Kathleen G. Haynes  Marcio L. Guedes 《American Journal of Potato Research》2018,95(6):729-734

Recently proposals have been made in both Europe and North America to try to radically change potato breeding strategy from a tetraploid, heterozygous crop to a diploid inbred crop. As part of that effort, clones from the long-day adapted, late blight resistant diploid hybrid Solanum phureja – S. stenotomum population were selfed to begin the process of developing inbred lines. In March of 2016 and 2017, 42 diploid clones from the above-mentioned population were selfed in the greenhouse in Beltsville, MD. In 2016 and 2017, 10 and 13 clones failed to flower, respectively. Among the remaining clones, 716 pollinations were made in 2016, resulting in 57 fruit from 17 clones, and 3742 seeds; 801 pollinations were made in 2017, resulting in 34 fruit from 12 clones, and 1903 seeds. Nine clones were successfully selfed both years. Percent successful selfs was significantly higher in 2016 (7.96%) than in 2017 (4.24%). The most prolific clones in 2016 were BD1241–1 (34% successful selfs, 1090 seed), BD1218–3 (25% successful selfs, 638 seed), BD1215–1 (5% successful selfs, 411 seed), BD1243–1 (23% successful selfs, 232 seed). In contrast, the most prolific clones in 2017 were BD1230–2 (25% successful selfs, 537 seed), BD1203–3 (23% successful selfs, 391 seed), and BD1229–1 (11% successful selfs, 388 seed). These results indicate that there is sufficient self-compatibililty in this population to generate large numbers of inbred individuals, but that genotype x environment interactions are large. Attempts to generate selfed seed should be made over several years to maximize the genetic base of the selfed population.  相似文献   

Effect of Solvent System on Extractability of Lipidic Components of Scenedesmus obliquus (M2-1) and Gloeothece sp. on Antioxidant Scavenging Capacity Thereof     

Helena M. Amaro  Fátima Fernandes  Patrícia Valent?o  Paula B. Andrade  I. Sousa-Pinto  F. Xavier Malcata  A. Catarina Guedes 《Marine drugs》2015,13(10):6453-6471

Microalgae are well known for their biotechnological potential, namely with regard to bioactive lipidic components—especially carotenoids and polyunsaturated fatty acids (PUFA), well-known for therapeutic applications based on their antioxidant capacity. The aim of this work was to evaluate the influence of four distinct food-grade solvents upon extractability of specific lipidic components, and on the antioxidant capacity exhibited against both synthetic (2,2-diphenyl-1-picrylhydrazyl (DPPH^•) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS^+•)) and biological reactive species (O₂^•− and ^•NO⁻). A eukaryotic microalga (Scenedesmus obliquus (M2-1)) and a prokaryotic one (Gloeothece sp.) were used as case studies. Concerning total antioxidant capacity, the hexane:isopropanol (3:2) and acetone extracts of Sc. obliquus (M2-1) were the most effective against DPPH^• and ABTS^+•, respectively. Gloeothece sp. ethanol extracts were the most interesting scavengers of O₂^•−, probably due the high content of linolenic acid. On the other hand, acetone and hexane:isopropanol (3:2) extracts were the most interesting ones in ^•NO⁻ assay. Acetone extract exhibited the best results for the ABTS assay, likely associated to its content of carotenoids, in both microalgae. Otherwise, ethanol stood out in PUFA extraction. Therefore, profiles of lipidic components extracted are critical for evaluating the antioxidant performance—which appears to hinge, in particular, on the balance between carotenoids and PUFAs.  相似文献   

Faecal shedding and serological cross‐sectional study of Lawsonia intracellularis in horses in the state of Minas Gerais,Brazil     

C. V. Guimarães‐Ladeira  M. S. Palhares  J. S. V. Oliveira  M. A. Ramirez  R. M. C. Guedes 《Equine veterinary journal》2009,41(6):593-596

Reason for performing the study: Proliferative enteropathy, caused by the intracellular bacterium Lawsonia intracellularis, has been described in horses in Australia, the USA, Canada and European countries but has not been reported in Latin America. The prevalence of the disease in horses worldwide is unknown. Objective: To evaluate the presence of subclinical L. intracellularis infection in horses in the state of Minas Gerais, Brazil. Methods: A longitudinal study using serology and PCR for detecting antibodies (IgG) and shedding of L. intracellularis in faecal samples, respectively, was conducted using a total of 223 horses from 14 different horse farms in Minas Gerais, and from the Veterinary School of UFMG equine herds in Minas Gerais. The immunoperoxidase technique in glass slides was used as the serological test. Results: Twenty‐one horse sera had immunoglobulin G titres of 1:60 and were considered positive. The PCR technique in faeces for L. intracellularis DNA identified 7 horses as faecal shedders. Horses shedding the organism appeared healthy, indicating that subclinical infection of L. intracellularis occurred in the horses. Conclusion: Seropositivity and detection of faecal shedding of L. intracellularis indicates the presence of the agent in the equine population in Minas Gerais. Potential relevance: Results of this study should alert clinicians in countries where proliferative enteropthy in horses has not been reported to consider this disease as a possible cause of enteric disease.  相似文献   

Millets, Rice, Social Complexity, and the Spread of Agriculture to the Chengdu Plain and Southwest China     

Jade d��Alpoim Guedes 《Rice》2011,4(3-4):104-113

Southwest China played a pivotal role in the spread of agriculture across East and Southeast Asia. Both rice and millet were important in the spread of populations and the expansion of agriculture into this region. Recent finds in the mountainous peripheries of Sichuan Province show that the earliest inhabitants of this region practiced a combination of broomcorn and foxtail millet agriculture (ca 4000?C2500 BC). These crops are adapted to high altitude and arid environments, which facilitated their movement across this region and eventually into the Tibetan Plateau. At around 2700 BC, a combined system of rice and foxtail millet agriculture appears suddenly in sites of the Baodun culture on the Chengdu Plain. The use of this double cropping system provided advantages to the inhabitants of this region in both risk reduction and yield. I argue that this had important consequences for spurring population growth, facilitating expansion into new territories and the development of social complexity.  相似文献   

Male multiple matings and reproductive success in commodity-adapted strains of <Emphasis Type="Italic">Sitophilus oryzae</Emphasis>     

Christos G. Athanassiou  Nickolas G. Kavallieratos  Giovanni Benelli  Raul Narciso C. Guedes 《Journal of pest science》2018,91(3):1073-1080

Multiple matings occur in many species of stored-grain insect pests, such as the rice weevil Sitophilus oryzae (L.), with both female and male mating more than once and with more than one partner. Multiple female mating in S. oryzae increased lifetime fecundity by extending the period of time progeny were produced, but consequences of multiple male mating in S. oryzae were not yet studied although it is likely to increase male fitness by increasing offspring production. Here, the effects of polygynous mating on male mating behavior, success, and fitness were assessed in two strains of S. oryzae, one adapted to barley and another to wheat. Two insect strains were considered because they may differ in response depending on the host grain, which present distinct nutritional value to the insects. Mating by pairs formed between the two strains did not impact mating success, but wheat-adapted females exhibited longer mating duration, which was positively correlated with progeny production. Wheat-adapted males exhibited higher fertility than barley-adapted males. When male multiple matings were considered in successive polygynous matings, late matings led to lower non-cumulative values of progeny production, but higher cumulative performance, and wheat-adapted S. oryzae always performed better. Thus, male fitness and grain losses in wheat are higher than in barley, even when S. oryzae was adapted to the latter.  相似文献   

Managing fall armyworm,Spodoptera frugiperda (Lepidoptera: Noctuidae), with Bt maize and insecticides in southern Brazil          下载免费PDF全文

Leonardo M Burtet  Oderlei Bernardi  Adriano A Melo  Maiquel P Pes  Thiago T Strahl  Jerson VC Guedes 《Pest management science》2017,73(12):2569-2577

  相似文献   

Biofilms of Candida spp. from the ocular conjunctiva of horses with reduced azole susceptibility: a complicating factor for the treatment of keratomycosis?          下载免费PDF全文

Raimunda Sâmia Nogueira Brilhante  Paula Vago Bittencourt  Débora de Souza Collares Castelo‐Branco  Glaucia Morgana de Melo Guedes  Jonathas Sales de Oliveira  Lucas Pereira Alencar  Rossana de Aguiar Cordeiro  Mariana Pinheiro  Evilázio Fernandes Nogueira‐Filho  Waldemiro de Aquino Pereira‐Neto  José Júlio Costa Sidrim  Marcos Fábio Gadelha Rocha 《Veterinary ophthalmology》2017,20(6):539-546

  相似文献