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1.
J Nanobiotechnology ; 21(1): 166, 2023 May 25.
Article in English | MEDLINE | ID: mdl-37231443

ABSTRACT

BACKGROUND: The biogenic synthesis of metallic nanoparticles is a green alternative that reduces the toxicity of this nanomaterials and may enable a synergy between the metallic core and the biomolecules employed in the process enhancing biological activity. The aim of this study was to synthesize biogenic titanium nanoparticles using the filtrate of the fungus Trichoderma harzianum as a stabilizing agent, to obtain a potential biological activity against phytopathogens and mainly stimulate the growth of T. harzianum, enhancing its efficacy for biological control. RESULTS: The synthesis was successful and reproductive structures remained in the suspension, showing faster and larger mycelial growth compared to commercial T. harzianum and filtrate. The nanoparticles with residual T. harzianum growth showed inhibitory potential against Sclerotinia sclerotiorum mycelial growth and the formation of new resistant structures. A great chitinolytic activity of the nanoparticles was observed in comparison with T. harzianum. In regard to toxicity evaluation, an absence of cytotoxicity and a protective effect of the nanoparticles was observed through MTT and Trypan blue assay. No genotoxicity was observed on V79-4 and 3T3 cell lines while HaCat showed higher sensitivity. Microorganisms of agricultural importance were not affected by the exposure to the nanoparticles, however a decrease in the number of nitrogen cycling bacteria was observed. In regard to phytotoxicity, the nanoparticles did not cause morphological and biochemical changes on soybean plants. CONCLUSION: The production of biogenic nanoparticles was an essential factor in stimulating or maintaining structures that are important for biological control, showing that this may be an essential strategy to stimulate the growth of biocontrol organisms to promote more sustainable agriculture.


Subject(s)
Hypocreales , Metal Nanoparticles , Trichoderma , Trichoderma/chemistry , Trichoderma/metabolism , Titanium/pharmacology , Titanium/metabolism , Metal Nanoparticles/toxicity
2.
Int J Nanomedicine ; 7: 3555-65, 2012.
Article in English | MEDLINE | ID: mdl-22848179

ABSTRACT

BACKGROUND: Agricultural products and by products provide the primary materials for a variety of technological applications in diverse industrial sectors. Agro-industrial wastes, such as cotton and curaua fibers, are used to prepare nanofibers for use in thermoplastic films, where they are combined with polymeric matrices, and in biomedical applications such as tissue engineering, amongst other applications. The development of products containing nanofibers offers a promising alternative for the use of agricultural products, adding value to the chains of production. However, the emergence of new nanotechnological products demands that their risks to human health and the environment be evaluated. This has resulted in the creation of the new area of nanotoxicology, which addresses the toxicological aspects of these materials. PURPOSE AND METHODS: Contributing to these developments, the present work involved a genotoxicological study of different nanofibers, employing chromosomal aberration and comet assays, as well as cytogenetic and molecular analyses, to obtain preliminary information concerning nanofiber safety. The methodology consisted of exposure of Allium cepa roots, and animal cell cultures (lymphocytes and fibroblasts), to different types of nanofibers. Negative controls, without nanofibers present in the medium, were used for comparison. RESULTS: The nanofibers induced different responses according to the cell type used. In plant cells, the most genotoxic nanofibers were those derived from green, white, and brown cotton, and curaua, while genotoxicity in animal cells was observed using nanofibers from brown cotton and curaua. An important finding was that ruby cotton nanofibers did not cause any significant DNA breaks in the cell types employed. CONCLUSION: This work demonstrates the feasibility of determining the genotoxic potential of nanofibers derived from plant cellulose to obtain information vital both for the future usage of these materials in agribusiness and for an understanding of their environmental impacts.


Subject(s)
Cellulose/toxicity , DNA Damage , Nanofibers/toxicity , 3T3 Cells , Adolescent , Analysis of Variance , Animals , Cells, Cultured , Chromosome Aberrations , Comet Assay , Cotton Fiber , Humans , Leukocytes, Mononuclear/drug effects , Mice , Mitotic Index , Mutagenicity Tests , Nanofibers/ultrastructure , Nanotechnology , Onions , Seeds , Young Adult
3.
Article in Portuguese | LILACS-Express | VETINDEX | ID: biblio-1493182

ABSTRACT

This study aimed to investigate the efficiency and standards in the superrovulatory response to products with different relationships FSH:LH. It Were used 43 female Boer goats breed. On a random day of the estrous cycle, the animals received half of an implant of progesterone (Crestar®). In the eleventh day, began stimulation to superovulation through the use of FSH fractionated in six decreasing doses administered every 12 hours and the animals were separated into two groups: group I (GI, n=22) received 200mg of FSH (Folltropin®) intramuscularly (i.m) on days D11 (62,5mg), D12 (35,0mg) and D13 (2,5mg), while the group II (GII, n=21) received 300UI FSH (Pluset®) intramuscularly on days D11 (75UI), D12 (50UI) and D13 (25UI). In 60 and 72h after onset of superovulation the implants were removed and applied two doses of 125µg de Cloprostenol (Ciosin®) by intravulvosubmucosal in all animals. Twelve, 24 and 36 hours after removal of the implant, the females were placed with four breeders to be covered. In D16, the implants were reinserted and 24 hours before collection of embryos the implants were withdrawl and administered 125µg de Cloprostenol in each animal intramuscularly. Embryo were collected on D21, selected and classified. The results obtained in this study showed no statistical difference between groups regarding the number of recovered structures, viable embryos, degenerat


Objetivou-se averiguar a eficiência e padrões na resposta superovulatória de caprinos da raça Boer submetidos a produtos com diferentes relações FSH:LH. Foram utilizadas 43 fêmeas caprinas da raça Boer. Em um dia aleatório do ciclo estral, os animais receberam metade de um implante de progesterona (Crestar®). No dia 11, iniciou-se o estímulo à superovulação por meio da utilização do FSH fracionado em seis doses decrescentes administradas a cada 12 horas e os animais foram separados em dois grupos: o grupo I (GI, n=22) recebeu 200mg de FSH (Folltropin®) por via intramuscular (i.m.) nos dias D11 (62,5mg), D12 (35,0mg) e D13 (2,5mg), enquanto o grupo II (GII, n=21) recebeu 300UI de FSH (Pluset®) por via i.m. nos dias D11 (75UI), D12 (50UI) e D13 (25UI). Nas 60 e 72h após o início da superovulação foram retirados os implantes, e aplicaram-se duas doses de 125µg de Cloprostenol (Ciosin®) por via intravulvosubmucosa em todos os animais. Doze, 24 e 36 horas após a remoção dos implantes, as fêmeas foram colocadas com quatro reprodutores para serem cobertas. No D16, os implantes foram reinseridos e, nas 24h antes da coleta dos embriões, retiraram-se os implantes, e administrou-se 125µg de Cloprostenol i.m. a cada animal. Os embriões foram coletados no D21, selecionados e classificados. Os resultados obtidos nesse estudo mostraram que não houve diferença estatística entre os grupos, quan

4.
Article in Portuguese | VETINDEX | ID: vti-712185

ABSTRACT

This study aimed to investigate the efficiency and standards in the superrovulatory response to products with different relationships FSH:LH. It Were used 43 female Boer goats breed. On a random day of the estrous cycle, the animals received half of an implant of progesterone (Crestar®). In the eleventh day, began stimulation to superovulation through the use of FSH fractionated in six decreasing doses administered every 12 hours and the animals were separated into two groups: group I (GI, n=22) received 200mg of FSH (Folltropin®) intramuscularly (i.m) on days D11 (62,5mg), D12 (35,0mg) and D13 (2,5mg), while the group II (GII, n=21) received 300UI FSH (Pluset®) intramuscularly on days D11 (75UI), D12 (50UI) and D13 (25UI). In 60 and 72h after onset of superovulation the implants were removed and applied two doses of 125µg de Cloprostenol (Ciosin®) by intravulvosubmucosal in all animals. Twelve, 24 and 36 hours after removal of the implant, the females were placed with four breeders to be covered. In D16, the implants were reinserted and 24 hours before collection of embryos the implants were withdrawl and administered 125µg de Cloprostenol in each animal intramuscularly. Embryo were collected on D21, selected and classified. The results obtained in this study showed no statistical difference between groups regarding the number of recovered structures, viable embryos, degenerat


Objetivou-se averiguar a eficiência e padrões na resposta superovulatória de caprinos da raça Boer submetidos a produtos com diferentes relações FSH:LH. Foram utilizadas 43 fêmeas caprinas da raça Boer. Em um dia aleatório do ciclo estral, os animais receberam metade de um implante de progesterona (Crestar®). No dia 11, iniciou-se o estímulo à superovulação por meio da utilização do FSH fracionado em seis doses decrescentes administradas a cada 12 horas e os animais foram separados em dois grupos: o grupo I (GI, n=22) recebeu 200mg de FSH (Folltropin®) por via intramuscular (i.m.) nos dias D11 (62,5mg), D12 (35,0mg) e D13 (2,5mg), enquanto o grupo II (GII, n=21) recebeu 300UI de FSH (Pluset®) por via i.m. nos dias D11 (75UI), D12 (50UI) e D13 (25UI). Nas 60 e 72h após o início da superovulação foram retirados os implantes, e aplicaram-se duas doses de 125µg de Cloprostenol (Ciosin®) por via intravulvosubmucosa em todos os animais. Doze, 24 e 36 horas após a remoção dos implantes, as fêmeas foram colocadas com quatro reprodutores para serem cobertas. No D16, os implantes foram reinseridos e, nas 24h antes da coleta dos embriões, retiraram-se os implantes, e administrou-se 125µg de Cloprostenol i.m. a cada animal. Os embriões foram coletados no D21, selecionados e classificados. Os resultados obtidos nesse estudo mostraram que não houve diferença estatística entre os grupos, quan

5.
Article in Portuguese | VETINDEX | ID: vti-717144

ABSTRACT

This study aimed to investigate the efficiency and standards in the superrovulatory response to products with different relationships FSH:LH. It Were used 43 female Boer goats breed. On a random day of the estrous cycle, the animals received half of an implant of progesterone (Crestar®). In the eleventh day, began stimulation to superovulation through the use of FSH fractionated in six decreasing doses administered every 12 hours and the animals were separated into two groups: group I (GI, n=22) received 200mg of FSH (Folltropin®) intramuscularly (i.m) on days D11 (62,5mg), D12 (35,0mg) and D13 (2,5mg), while the group II (GII, n=21) received 300UI FSH (Pluset®) intramuscularly on days D11 (75UI), D12 (50UI) and D13 (25UI). In 60 and 72h after onset of superovulation the implants were removed and applied two doses of 125µg de Cloprostenol (Ciosin®) by intravulvosubmucosal in all animals. Twelve, 24 and 36 hours after removal of the implant, the females were placed with four breeders to be covered. In D16, the implants were reinserted and 24 hours before collection of embryos the implants were withdrawl and administered 125µg de Cloprostenol in each animal intramuscularly. Embryo were collected on D21, selected and classified. The results obtained in this study showed no statistical difference between groups regarding the number of recovered structures, viable embryos, degenerate embryos and unfertilized structures. So, the different relationships FSH:LH evaluated did not affect embryos production and quality.


Objetivou-se averiguar a eficiência e padrões na resposta superovulatória de caprinos da raça Boer submetidos a produtos com diferentes relações FSH:LH. Foram utilizadas 43 fêmeas caprinas da raça Boer. Em um dia aleatório do ciclo estral, os animais receberam metade de um implante de progesterona (Crestar®). No dia 11, iniciou-se o estímulo à superovulação por meio da utilização do FSH fracionado em seis doses decrescentes administradas a cada 12 horas e os animais foram separados em dois grupos: o grupo I (GI, n=22) recebeu 200mg de FSH (Folltropin®) por via intramuscular (i.m.) nos dias D11 (62,5mg), D12 (35,0mg) e D13 (2,5mg), enquanto o grupo II (GII, n=21) recebeu 300UI de FSH (Pluset®) por via i.m. nos dias D11 (75UI), D12 (50UI) e D13 (25UI). Nas 60 e 72h após o início da superovulação foram retirados os implantes, e aplicaram-se duas doses de 125µg de Cloprostenol (Ciosin®) por via intravulvosubmucosa em todos os animais. Doze, 24 e 36 horas após a remoção dos implantes, as fêmeas foram colocadas com quatro reprodutores para serem cobertas. No D16, os implantes foram reinseridos e, nas 24h antes da coleta dos embriões, retiraram-se os implantes, e administrou-se 125µg de Cloprostenol i.m. a cada animal. Os embriões foram coletados no D21, selecionados e classificados. Os resultados obtidos nesse estudo mostraram que não houve diferença estatística entre os grupos, quanto ao número de estruturas recuperadas, embriões viáveis, embriões degenerados e estruturas não fertilizadas. Portanto, as diferentes relações FSH:LH avaliadas não afetaram a produção e a qualidade de embriões.

6.
J Hazard Mater ; 186(2-3): 1645-51, 2011 Feb 28.
Article in English | MEDLINE | ID: mdl-21215514

ABSTRACT

The purpose of this work was to develop a modified release system for the herbicide ametryn by encapsulating the active substance in biodegradable polymer microparticles produced using the polymers poly(hydroxybutyrate) (PHB) or poly(hydroxybutyrate-valerate) (PHBV), in order to both improve the herbicidal action and reduce environmental toxicity. PHB or PHBV microparticles containing ametryn were prepared and the efficiencies of herbicide association and loading were evaluated, presenting similar values of approximately 40%. The microparticles were characterized by scanning electron microscopy (SEM), which showed that the average sizes of the PHB and PHBV microparticles were 5.92±0.74 µm and 5.63±0.68 µm, respectively. The ametryn release profile was modified when it was encapsulated in the microparticles, with slower and more sustained release compared to the release profile of pure ametryn. When ametryn was associated with the PHB and PHBV microparticles, the amount of herbicide released in the same period of time was significantly reduced, declining to 75% and 87%, respectively. For both types of microparticle (PHB and PHBV) the release of ametryn was by diffusion processes due to anomalous transport (governed by diffusion and relaxation of the polymer chains), which did not follow Fick's laws of diffusion. The results presented in this paper are promising, in view of the successful encapsulation of ametryn in PHB or PHBV polymer microparticles, and indications that this system may help reduce the impacts caused by the herbicide, making it an environmentally safer alternative.


Subject(s)
Herbicides/chemistry , Triazines/chemistry , Agriculture , Algorithms , Area Under Curve , Delayed-Action Preparations , Drug Compounding , Kinetics , Microscopy, Electron, Scanning , Microspheres , Occupational Exposure/prevention & control , Particle Size , Polyesters/chemistry , Polymers , Solubility , Ultrafiltration , Water
7.
J Food Sci ; 75(6): N89-96, 2010 Aug 01.
Article in English | MEDLINE | ID: mdl-20722945

ABSTRACT

The use of nanoparticles in food packaging has been proposed on the basis that it could improve protection of foods by, for example, reducing permeation of gases, minimizing odor loss, and increasing mechanical strength and thermal stability. Consequently, the impacts of such nanoparticles on organisms and on the environment need to be investigated to ensure their safe use. In an earlier study, Moura and others (2008a) described the effect of addition of chitosan (CS) and poly(methacrylic acid) (PMAA) nanoparticles on the mechanical properties, water vapor, and oxygen permeability of hydroxypropyl methylcellulose films used in food packaging. Here, the genotoxicity of different polymeric CS/PMAA nanoparticles (size 60, 82, and 111 nm) was evaluated at different concentration levels, using the Allium cepa chromosome damage test as well as cytogenetic tests employing human lymphocyte cultures. Test substrates were exposed to solutions containing nanoparticles at polymer mass concentrations of 1.8, 18, and 180 mg/L. Results showed no evidence of DNA damage caused by the nanoparticles (no significant numerical or structural changes were observed), however the 82 and 111 nm nanoparticles reduced mitotic index values at the highest concentration tested (180 mg/L), indicating that the nanoparticles were toxic to the cells used at this concentration. In the case of the 60 nm CS/PMAA nanoparticles, no significant changes in the mitotic index were observed at the concentration levels tested, indicating that these particles were not toxic. The techniques used show promising potential for application in tests of nanoparticle safety envisaging the future use of these materials in food packaging.


Subject(s)
Chitosan/toxicity , Food Packaging , Mutagens/toxicity , Nanoparticles/chemistry , Nanoparticles/toxicity , Polymethacrylic Acids/toxicity , Cells, Cultured , Chromosome Aberrations/drug effects , Chromosomes, Plant/drug effects , Cytogenetic Analysis , Dose-Response Relationship, Drug , Humans , Lymphocytes/drug effects , Microscopy, Electron, Transmission , Mitosis/drug effects , Mitotic Index , Mutagenicity Tests , Nanoparticles/ultrastructure , Onions/drug effects , Onions/genetics , Particle Size , Plant Roots/drug effects , Seedlings/drug effects , Seedlings/genetics
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