ANTONIO JEDSON CALDEIRA BRANT

ANTONIO JEDSON CALDEIRA BRANT

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Cellulose nanoparticles extracted from sugarcane bagasse and their use in biodegradable recipients for improving physical properties and water barrier of the latter
2020 - BRANT, ANTONIO J.C.; NAIME, NATALIA; LUGAO, ADEMAR B.; PONCE, PATRICIA
The present work firstly aimed to obtain cellulose from sugarcane bagasse by using alkaline methods in pulping/delignifying and, at bleaching stages, using sodium chlorite, glacial acetic acid, and hydrogen peroxide, associated to NaOH/KOH. The process was carried out at temperatures varying from 55˚C to 110˚C, under magnetic stirring in various steps lasting from 2 h to 12 h. The yields of the two cellulose extracted, SCB24-Na-I and SCB24-Na-II, were 37% and 41%, respectively, from samples of ca. 15 g of the bagasse. Secondly, it is to extract nanoparticles from the obtained celluloses via acid hydrolysis (with 77% H2SO4) to lately be tested as reinforcement in biodegradable packagings. Both celluloses and their respective nanoparticles were characterized by several techniques, among them ATR-FTIR, DSC-TGA, XRD, SEM, and TEM. Despite that the yields of cellulose nanoparticles have been low, the preliminary studies of their use in biodegradable films coated on biodegradable pots were promising.
Simultaneous hydrogel crosslinking and silver nanoparticle formation by using ionizing radiation to obtain antimicrobial hydrogels
2019 - ALCANTARA, M.T.S.; LINCOPAN, N.; SANTOS, P.M.; RAMIREZ, P.A.; BRANT, A.J.C.; RIELLA, H.G.; LUGAO, A.B.
Hydrogel dressings are crosslinked hydrophilic polymers able of swelling in presence of water and can be used in many different types of wound care. In turn, in wound care, silver has been used for a long time as an effective antimicrobial agent. Recent studies have demonstrated an increase of its antimicrobial action when it is used at nanometer scale, that is, as silver nanoparticles (AgNPs), which have anti-inflammatory effect on infected wounds, rashes, and mesh skin grafts. The objective of this work was to study hydrogel dressings containing AgNPs from silver nitrate, synthesized by radiation involving the formation of silver nanoparticles with simultaneous occurrence of crosslinking and sterilization of the polymer systems. One of the hydrogels was prepared with poly(N-vinyl-2- pyrrolidone) (PVP) and the other with poly(vinyl alcohol) (PVA) as main studied polymers. An aqueous solution of AgNO3 was added to both polymer systems separately. The AgNPs synthesis, polymer crosslinking and dressing sterilization were achieved simultaneously by irradiating the resultant solutions with gamma-rays from a 60Co source. Gel fraction, swelling in reverse osmosis water, SEM-EDS, UVvisible spectroscopy, and antimicrobial activity were performed and characterized. The obtained results showed that the dressings have a soft consistency, high degree of crosslinking and swelling, homogeneous distribution of AgNPs with peaks of plasmonic bands about 400 nm, but only PVP hydrogel showed antimicrobial properties to P. aeruginosa and normal S. aureus. Moreover, this hydrogel also showed antimicrobial properties to S. aureus strain multiresistant to penicillins, cephalosporins, carbapenems, sulfonamides, tetracyclines, quinolones, and aminoglycosides, whereas the PVA hydrogel showed antimicrobial properties to P. aeruginosa and bacteriostatic activity to S. aureus. The results suggest that both synthesized dressings have potential for use in wounds and burns infected with gram-positive and gram-negative bacteria.
Influence of ionizing radiation on biodegradable foam trays for food packaging obtained from irradiated cassava starch
2018 - BRANT, ANTONIO J.C.; NAIME, NATALIA; LUGAO, ADEMAR B.; PONCE, PATRICIA
Biodegradable polymers, such as starch, cellulose, and derivatives thereof, are being studied to produce innovative packaging in the most diverse shapes (films, bags, trays, bottles, etc.) to attend this current market trend. The aim of this work was to produce foam trays from cassava starch for food packaging via extrusion followed by thermoforming process. Their formulations were based on unirradiated and γ-irradiated starches at diverse radiation absorbed doses (in kGy) in order to evaluate the influence of the irradiated starches on the physical properties of the trays. Water absorption results showed an irregular increase with the increase of the absorbed dose ( for example, 26.32% and 39.84% for the trays based on unirradiated starch 0 kGy and 1:1 (w/w) mixture of starches 0 kGy and 100.0 kGy, respectively). Other physicochemical properties were evaluated from the starches utilized and the trays obtained. Aerobic biodegradation of the foams by mass loss also was checked in soil burial test.
Influência do tipo de tubetes de reflorestamento (biodegradáveis e de plástico) no desenvolvimento de mudas de Eucalyptus saligna
2017 - NAIME, NATALIA; BRANT, ANTONIO J.C.; LUGAO, ADEMAR B.; PONCE, PATRICIA
Este trabalho teve como objetivo estudar a influência do tipo de tubetes de reflorestamento no desenvolvimento de mudas de Eucalyptus saligna, durante a fase de viveiro. Para tanto, foram analisados tubetes plásticos e biodegradáveis (sendo os primeiros obtidos do mercado brasileiro e os últimos fabricados pela empresa BIO&GREEN, a partir do bagaço de cana-de-açúcar) de diferentes volumes, comparando-os quanto (1) ao desenvolvimento das mudas de eucalipto e (2) às suas integridades físicas, até completarem 90 dias da semeadura. Os resultados mostraram que as mudas de eucalipto, em viveiro, se desenvolveram melhor nos recipientes de polietileno e indicaram que quanto maior o volume do tubete, melhor desenvolvida é a planta.
Production of Mini Tomato Seedlings in Biodegradable
2016 - NAIME, N.; BRANT, A.J.C.; LUGAO, A.B.; PONCE, P.
The objective of this study was to analyze the influence of different types and fertilizer application in the development of mini tomatoes seedlings (Lycopersicum esculentum var. Cerasiforme) placed in biodegradable foamed recipients, manufactured with sugarcane fibers, cassava starch and plasticizer. Stalk diameters, seedling heights, quantity of leaves and the physical integrity of packaging at 30, 60 and 90 days after sowing were evaluated. The tomato productivity was significantly increased by the use of fertilizer incorporated into the substrate. This significance was not observed for the seedlings with fertilizer incorporated into the packaging – although, in general, these are higher and have more leaves when compared to those without fertilizer. All packaging remained intact up to 30 days after sowing. From this period on, as expected, the biodegradable packaging began to decompose. However, at 60 days, the tomato seedlings remained intact and suitable for planting in the soil.
Biodegradable foam trys obtained from mixtures of non-irradiated and irradited Cassava starches
2015 - BRANT, A.J.C.; NAIME, N.; LUGAO, A.B.; PONCE, P.
Obtencao de superabsorventes a partir de misturas de poliacrilamida e agua reticuladas com glioxal
2010 - NAIME, N.; BRANT, A.J.C.; GUADAGNIN, H.C.; ALCANTARA, M.T.S.; PONCE, P.; LUGAO, A.B.
Biodegradability of PP/HMSPP and natural and synthetic polymers blends in function of gamma irradiation degradation
2012 - CARDOSO, ELISABETH C.L.; SCAGLIUSI, SANDRA R.; LIMA, LUIS F.C.P.; BUENO, NELSON R.; BRANT, ANTONIO J.C.; PARRA, DUCLERC F.; LUGAO, ADEMAR B.
Hidrogeis superabsorventes a partir de poliacrilamida
2010 - GUADAGNIN, H.C.; BRANT, A.J.C.; NAIME, N.; ALCANTARA, M.T.S.; PONCE, P.; LUGAO, A.B.
Estudo da reticulacao induzida por radiacao gama de misturas de poliacrilamida anionica e agua
2010 - ALCANTARA, M.T.S.; BRANT, A.J.C.; NAIME, N.; GUADAGNIN, H.C.; PONCE, P.; LUGAO, A.B.