568 research outputs found

    Influence of preparation procedures on the phenolic content, antioxidant and antidiabetic activities of green and black teas

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    The influence of common tea preparation procedures (temperature, infusion time, consumption time interval and tea bag/loose-leaf) and the type of water used, on the total phenolic content (TPC), the radical scavenging activity and the alpha-glucosidase inhibitory activity were assessed. Higher TPC and antioxidant activity were obtained when using lower mineralized waters. Tea bags also evidenced higher antioxidant activity than loose-leaf samples. Under the same conditions (90 degrees C and five minutes of infusion time) green tea contains almost twice the quantity of polyphenols and the free radical scavenging ability of black tea. In the alpha-glucosidase assay all infusions were active (97-100 %). Furthermore, HPLC allowed to identify some of the polyphenols present in both teas and to monitor their composition change with time. After twenty-four hours, the antioxidant activity was maintained without significant changes, but a small decrease in enzyme inhibition was observed, although this activity was still very high.info:eu-repo/semantics/publishedVersio

    Avaliação da produtividade de colmos em uma cronossequĂȘncia de canaviais cultivados em sistema orgĂąnico.

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    No cultivo orgĂąnico da cana-de-açĂșcar nĂŁo Ă© permitido o uso de fertilizantes sintĂ©ticos altamente solĂșveis e tambĂ©m o uso de agrotĂłxicos. A adubação Ă© feita apenas com adubos orgĂąnicos e os pĂłs de rocha tambĂ©m sĂŁo permitidos. A vinhaça e a torta de filtro, resĂ­duos da indĂșstria sucroalcooleira, suprem quase que completamente a demanda de nitrogĂȘnio, fĂłsforo e potĂĄssio requeridos pela cultura.PĂŽster - pĂłs-graduação

    AlteraçÔes relacionadas ao amaciamento da uva Superior Seedless durante a maturação.

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    Este trabalho teve como objetivo caracterizar o metabolismo do carbono e energético durante o ajustamento osmótico em videiras submetidas ao estresse hídrico

    Carbono e densidade do solo em uma cronosequĂȘncia de canaviais cultivado em sistema orgĂąnico.

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    O Brasil Ă© um dos principais fornecedores de produtos agrĂ­colas primĂĄrios. A expansĂŁo da produção se deve Ă  exploração dos solos do Cerrado brasileiro. Atualmente o paĂ­s Ă© o maior produtor mundial de cana-de-açĂșcar. Nos Ășltimos anos a expansĂŁo da cultura ocorreu principalmente na regiĂŁo centro-oeste, onde predomina o bioma Cerrado. O sistema de cultivo orgĂąnico vem despontando como uma interessante alternativa como meio de promover a sustentabilidade da produção de cana-de-açĂșcar no bioma Cerrado, preservar o meio ambiente e reduzir a contaminação dos alimentos e em especial, dos trabalhadores rurais. O objetivo desse estudo foi avaliar o efeito do cultivo orgĂąnico da cana-de-açĂșcar sobre a densidade do solo e os estoques de carbono. Amostras de terra de ĂĄreas cultivadas com cana-de-açĂșcar hĂĄ 0, 2, e 10 anos na regiĂŁo de GoianĂ©sia-GO, foram analisadas quanto Ă  densidade do solo (Ds) e o teor de carbono (C) com o objetivo de quantificar o estoque de C e as alteraçÔes devidas a mudança no cultivo da cana de convencional sem queima para orgĂąnico. A densidade do solo diminuiu ao longo do uso do solo com o cultivo orgĂąnico da cana-de-açĂșcar, enquanto o conteĂșdo de C aumentou ao longo do tempo. O efeito do cultivo orgĂąnico sobre a Ds ocorreu atĂ© a camada de 30-40 cm. Na camada de 0-5 cm os valores reduziram na seguinte magnitude: 1,67 g cm-3, 1,26 g cm-3 e 1,22 g cm-3 para as ĂĄreas Org.0, Org.2 e Org.10, respectivamente e na camada 30-40 cm: 1,60 g cm-3, 1,33 g cm-3 e 1,32 g cm-3. ApĂłs 2 e 10 anos de cultivo orgĂąnico da cana-de-açĂșcar o estoque de carbono aumentou com 12,594 e 31,258 Mg ha-1 na camada superficial do solo 0-30 cm e com 20,768 e 51,147 Mg ha-1 numa camada de 0-100 cm, em comparação com o cultivo convencional sem queima

    Biocomposite macrospheres based on strontium-bioactive glass for application as bone fillers

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    Traditional bioactive glass powders are typically composed of irregular particles that can be packed into dense configurations presenting low interconnectivity, which can limit bone ingrowth. The use of novel biocomposite sphere formulations comprising bioactive factors as bone fillers are most advantageous, as it simultaneously allows for packing the particles in a 3-dimensional manner to achieve an adequate interconnected porosity, enhanced biological performance, and ultimately a superior new bone formation. In this work, we develop and characterize novel biocomposite macrospheres of Sr-bioactive glass using sodium alginate, polylactic acid (PLA), and chitosan (CH) as encapsulating materials for finding applications as bone fillers. The biocomposite macrospheres that were obtained using PLA have a larger size distribution and higher porosity and an interconnectivity of 99.7%. Loose apatite particles were observed on the surface of macrospheres prepared with alginate and CH by means of soaking into a simulated body fluid (SBF) for 7 days. A dense apatite layer was formed on the biocomposite macrospheresĂą surface produced with PLA, which served to protect PLA from degradation. In vitro investigations demonstrated that biocomposite macrospheres had minimal cytotoxic effects on a human osteosarcoma cell line (SaOS-2 cells). However, the accelerated degradation of PLA due to the degradation of bioactive glass may account for the observed decrease in SaOS-2 cells viability. Among the biocomposite macrospheres, those composed of PLA exhibited the most promising characteristics for their potential use as fillers in bone tissue repair applications.This work was funded by grant #2019/15960-6, São Paulo Research Foundation in Brazil (FAPESP) and the Portuguese Foundation for Science and Technology (FCT), Reference UID/CTM/50025/2019 and FCT/Minister of Science, Technology and Higher Education in Portugal (MCTES) and by European Regional Development Fund (FEDER) funds through the COMPETE 2020 Program in the framework of ORAiDEA project (ref n° 39985 - AAC 31/SI/2017). The authors would also like to acknowledge Materials Research Center (CENIMAT) of the Associated Laboratory Institute of Nanostructures, Nanomodeling and Nanofabrication (i3N), NOVA University of LisbonCENIMAT|i3N and National Council for Scientific and Technological Development in Brazil CNPq (303149/2018-3). Ibrahim Fatih Cengiz acknowledges the FCT distinction attributed to him under the “EstĂ­mulo ao Emprego CientĂ­fico” program (2021.01969.CEECIND). The authors thank the financial support provided under the projects: “HEALTH-UNORTE: Setting-up biobanks and regenerative medicine strategies to boost research in cardiovascular, musculoskeletal, neurological, oncological, immunological, and infectious diseases”, reference NORTE-01-0145-FEDER-000039, funded by the Norte Portugal Regional Coordination and Development Commission (CCDR-N), under the NORTE2020 Program; Projects LA/P/0037/2020, UIDP/50025/2020, and UIDB/50025/ 2020 of the Associate Laboratory i3N financed by national funds from FCT
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