147 research outputs found

    Periods Of Weed Interference In Maize Crops Cultivated In The First And Second Cycles

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    The interference of weeds in maize production may be reflected in grain yield losses that vary as a function of the density, stage and degree of aggressiveness of the species present. In the agricultural ecosystem, crops and weeds demand light, water, nutrients and space, which are frequently not available in sufficient quantities, leading to competition. The aim of this work was to determine the period of interference of weed plants, in particular of naked crabgrass (Digitaria nuda) on maize crop in the first and second harvest. The treatments were defined as increasing periods of coexistence and increasing control of weed community (7, 14, 21, 28, 35, 42, 49, and 56 days), two more controls, a control including one with weed control until the end of the culture cycle and another with coexistence until the harvest. For each period, were evaluated the stand of maize plants, length of ear, number of grains per row, number of rows per ear, cob, 100-grain weight, and grain productivity. The data obtained were subjected to analysis of variance using the F test, with average treatments compared using Tukey's test at 5% probability. Crop productivity was evaluated by means of regressions, the critical periods of interference were estimated. The critical timing of weed removal was 25 days for both harvests. The critical weed free period was 54 and 27 days for the first and second harvest respectively. For the conditions of the first and second harvest, the critical period of weed control was of 29 and 2 days respectively.3752867287

    Merlot grape pomace hydroalcoholic extract improves the oxidative and inflammatory states of rats with adjuvant-induced arthritis

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    Grape pomace is an agro-industrial residue produced worldwide. The purpose of this study was to identify and quantify the main phenolics present in an hydroalcohlic extract of a Merlot grape pomace and to investigate its effect on the oxidative and inflammatory states of adjuvant-induced arthritic rats. Daily doses of 250 mg of the extract per kg body weight were administered during 23 days. Several oxidative stress indicators in arthritic rats were maintained at their normal or closely normal levels in the plasma, liver and brain by the treatment. Additionally, the grape pomace also showed significant anti-inflammatory effects. From the 25 phenolics identified in the grape pomace extract the most abundant ones were catechin and catechin derivatives, which are possibly the most important antioxidant agents. The results suggest a potential applicability of the Merlot grape pomace hydroalcoholic extract in the improvement of the oxidative and inflammatory states in arthritic patients.The authors which to thank Anacharis Babeto de Sá-Nakanishi, Jurandir Fernando Comar and Leomara Floriano Ribeiro for their expert technical assistance. This work was financially supported by grants from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Proc. 302615/2011-3 and Proc. 307944/2015-8) and Fundação Araucária (Proc. 215/2014). Andréia A. Soares and Rúbia C. G. Corrêa were post-doc fellowship recipients of the Coordenação do Aperfeiçoamento de Pessoal do Ensino Superior (CAPES) and Fundação Araucária. The authors are also thankful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Program PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros (SFRH/BPD/107855/2015) grant. To POCI-01-0145-FEDER-006984 (LA LSRE-LCM), funded by ERDF, through POCI-COMPETE2020 and FCT.info:eu-repo/semantics/publishedVersio

    Food bioactive compounds and emerging techniques for their extraction: Polyphenols as a case study

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    Experimental studies have provided convincing evidence that food bioactive compounds (FBCs) have a positive biological impact on human health, exerting protective effects against noncommunicable diseases (NCD) including cancer and cardiovascular (CVDs), metabolic, and neurodegenerative disorders (NDDs). These benefits have been associated with the presence of secondary metabolites, namely polyphenols, glucosinolates, carotenoids, terpenoids, alkaloids, saponins, vitamins, and fibres, among others, derived from their antioxidant, antiatherogenic, anti-inflammatory, antimicrobial, antithrombotic, cardioprotective, and vasodilator properties. Polyphenols as one of the most abundant classes of bioactive compounds present in plant-based foods emerge as a promising approach for the development of efficacious preventive agents against NCDs with reduced side effects. The aim of this review is to present comprehensive and deep insights into the potential of polyphenols, from their chemical structure classification and biosynthesis to preventive effects on NCDs, namely cancer, CVDs, and NDDS. The challenge of polyphenols bioavailability and bioaccessibility will be explored in addition to useful industrial and environmental applications. Advanced and emerging extraction techniques will be highlighted and the high-resolution analytical techniques used for FBCs characterization, identification, and quantification will be considered.FCT (Fundação para a Ciência e a Tecnologia) through the CQM Base Fund-UIDB/00674/ 2020, the Programmatic Fund- UIDP/00674/2020, and the PhD fellowship SFRH/BD/116895/2016 granted to João Gonçalves. Madeira 14–20 Program, project PROEQUIPRAM-Reforço do Investimento em Equipamentos e Infraestruturas Científicas RAM (M1420-01-0145-FEDER-000008), ARDITIAgência Regional para o Desenvolvimento da Investigação Tecnologia e Inovação through the project M1420-01-0145-FEDER-000005-Centro de Química da Madeira-CQM+ (Madeira 14–20 Program) and Project M1420-09-5369-FSE-000001 for the Post-Doctoral fellowship granted to JAMP. Núcleo Regional da Madeira da Liga Portuguesa Contra o Cancro (NRM-LPCC) for the professional internship granted to Joselin Aguiar. FCT for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020). National funding by FCT, P.I., through the institutional scientific employment program-contract for L. Barros, and B.R. Albuquerque research grant (SFRH/BD/136370/2018). European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of the project Mobilizador Norte-01-0247-FEDER-024479: ValorNatural®. FEDER-Interreg España-Portugal programme for financial support through the project 0377_Iberphenol_ 6_E and TRANSCoLAB 0612_TRANS_CO_LAB_2_P. R.C.G. Corrêa is a research grant recipient of Cesumar Institute of Science Technology and Innovation (ICETI).info:eu-repo/semantics/publishedVersio

    Effects of in vitro gastrointestinal digestion and colonic fermentation on a rosemary (Rosmarinus officinalis L) extract rich in rosmarinic acid

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    The potential phytochemical losses occurring throughout the sequential steps of in-vitro gastrointestinal digestion and colonic fermentation of a rosemary aqueous extract were investigated. Crude (CE), digested (DE) and fermented (FE) extracts were characterized in terms of their phenolic profile and biological activities. Rosmarinic acid was the phytochemical that underwent the most significate transformation during digestion and fermentation, which amounted to 60% compared to the 26% degradation of the total phenolics. Overall, the simulated digestion step decreased the antioxidant activity estimated by DPPH, ABTS, FRAP, ORAC and TBARS assays. Both CE and DE did not present antiproliferative potential, however, FE exhibited a pronounced cytotoxic activity (GI50 = 116 µg/mL) against HeLa cells. CE and DE showed to be moderate inhibitors of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), S. aureus, Listeria monocytogenes, whilst the FE acted as a moderate inhibitor of MRSA and MSSA.G.A. Gonçalves and V.G. Correa thank Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the financial support provided for their post-graduate studies in the State University of Maringá. R.C.G. Corrêa thanks Conselho Nacional de Desenvolvimento Científico e Tecnologia ( CNPq ) for financing her postdoctoral research at State University of Maringá (Process number 167378/2017-1). R.M. Peralta (Project number 307944/2015-8) and A. Bracht (Project number 304090/2016-6) are CNPq research grant recipients. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013), L. Barros and R. Calhelha contracts; and also thank to FEDER-Interreg España-Portugal programme for financial support through the project 0377_Iberphenol_6_E. Appendix Ainfo:eu-repo/semantics/publishedVersio

    Potential anti-diabetic properties of Merlot grape pomace extract: an in vitro, in silico and in vivo study of α-amylase and α-glucosidase inhibition

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    A practical approach to control glycemia in diabetes is to use plant natural products that delay hydrolysis of complex sugars and promote the diminution of the release of glucosyl units into the blood plasma. Polyphenolics have been described as being effective in inhibiting amylases and α-glucosidases. Grape pomace is an important sub product of the wine industry, still rich in many compounds such as polyphenolics. In this context, the purpose of this study was to search for possible effects of a grape pomace extract on salivary and pancreatic α-amylases and α-glucosidase, as well as on intestinal glucose absorption. The Merlot grape pomace extract (MGPE) was prepared using a hydroalcoholic mixture (40% ethanol + 60% water). In vitro inhibition was quantified using potato starch (for amylases) and maltose (for α-glucosidase) as substrates. In vivo inhibition was evaluated by running starch and maltose tolerance tests in rats with or without administration of MGPE. Ranking of the extract compounds for its affinity to the α-amylases was accomplished by computer simulations using three different programs. Both α-amylases, pancreatic and salivary, were inhibited by the MGPE. No inhibition on α-glucosidase, however, was detected. The IC50 values were 90 ± 10 μg/mL and 143 ± 15 μg/mL for salivary and pancreatic amylases, respectively. Kinetically this inhibition showed a complex pattern, with multiple binding of the extract constituents to the enzymes. Furthermore, the in silico docking simulations indicated that several phenolic substances, e.g., peonidin-3-O-acetylglucoside, quercetin-3-O-glucuronide and isorhamnetin-3-O-glucoside, besides catechin, were the most likely polyphenols responsible for the α-amylase inhibition caused by MGPE. The hyperglycemic burst, an usual phenomenon that follows starch administration, was substantially inhibited by the MGPE. Our results suggest that the MGPE can be adequate for maintaining normal blood levels after food ingestion.The authors wish to thank to the Fundação Araucária (Brazil), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazil), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, Brazil), Cesumar Institute of Science Technology and Innovation (ICETI, Brazil), and FEDER-Interreg España-Portugal for their financial help.info:eu-repo/semantics/publishedVersio

    Structural assessment, toxicity, and increased antimicrobial activity

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    Scorpion venom is a rich source of biologically active components and various peptides with high-potential therapeutic use that have been characterized for their antimicrobial and antiproliferative activities. Stigmurin is a peptide identified from the Tityus stigmurus venom gland with high antibacterial and antiproliferative activities and low toxicity. Amino acid substitutions in peptides without a disulfide bridge sequence have been made with the aim of reducing their toxicity and increasing their biological activities. The purpose of this study was to evaluate the structural conformation and structural stability, as well as antimicrobial, antiproliferative, and hemolytic activities of two peptide analogs to Stigmurin, denominated StigA6 and StigA16. In silico analysis revealed the α-helix structure for both analog peptides, which was confirmed by circular dichroism. Data showed that the net charge and hydrophobic moment of the analog peptides were higher than those for Stigmurin, which can explain the increase in antimicrobial activity presented by them. Both analog peptides exhibited activity on cancerous cells similar to the native peptide; however, they were less toxic when tested on the normal cell line. These results reveal a potential biotechnological application of the analog peptides StigA6 and StigA16 as prototypes to new therapeutic agents.publishersversionpublishe
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