Biologia Vegetal

URI Permanente desta comunidade

http://repositorio.ufes.br/handle/10/17503
Programa de Pós-Graduação em Biologia Vegetal

Centro: CCHN
Telefone: (27) 4009 2588
URL do programa: http://www.biologiavegetal.ufes.br/

Navegar

Navegando Biologia Vegetal por Autor "Almeida, Stéfano Zorzal de"

Agora exibindo 1 - 5 de 5
  • Nenhuma Miniatura disponível
    Item
    Ecologia de algas perifíticas em uma lagoa costeira com múltiplos usos (lagoa Juara, Serra, ES)
    (Universidade Federal do Espírito Santo, 2011-02-23) Almeida, Stéfano Zorzal de; Milanez, Camilla Rozindo Dias; Fernandes, Valéria de Oliveira; Dias Junior, Camilo; Ferragut, Carla
    Coastal lagoons are shallow water bodies, usually oriented parallel to the coast and are often impacted by human activities. Juara lagoon (Serra, Brazil) is a shallow coastal environment that has multiple uses such as recreation, fishing and intensive aquaculture. Displays tributaries that convey untreated effluents. This study aimed to evaluate periphyton responses in two sampling sites subject to different human impacts. Three experimental structures containing artificial substrates (glass plates) were implanted at two sampling sites in Dec/2009: TR - within the intensive fish (net cage); and ED - near the mouth of the Laranjeira creek, disseminator of wastewater, and the headquarters of the Associação de Pescadores. Plants were sampled in each of the experimental structures after 21, 26 and 31 days of succession. Were evaluated: transparency, conductivity, pH, turbidity, total suspended solids, alkalinity, dissolved oxygen, water temperature, total nitrogen, nitrate, nitrite, ammonia nitrogen, total phosphorus, orthophosphate and silicate. The periphyton scrapings was analyzed by the following attributes: density (total and per class), richness (total and per class), biovolume (total and per class), diversity, evenness, abundance, dominance, photosynthetic pigments (chlorophyll a and b and carotenoid) pheophytin, dry weight and ash-free dry weight. The two sampling sites showed eutrophic characteristics, with ED had higher electrical conductivity, turbidity, total suspended solids, total alkalinity, total nitrogen, nitrate, ammonia nitrogen and orthophosphate. TR were recorded higher values for water temperature, water transparency and silicate. Density and total biovolume showed no differences between sampling sites. Bacillariophyceae were significantly higher at station TR for density and biovolume. Coscinodiscophyceae and Cyanophyceae density and biovolume were significantly higher in ED. Richness (total and per class), diversity, chlorophyll b, carotenoids, pheophytin, dry weight and ash-free dry weight showed no significant difference between the sampling stations. Chlorophyll a was higher at station ED. Impacts caused different responses in different periphytic community, especially in terms of their composition.
  • Nenhuma Miniatura disponível
    Item
    Efeitos de diferentes condições físicas e efluentes agrícolas sobre o cultivo de microalgas da família Scenedesmaceae como subsídio à aplicação biotecnológica.
    (Universidade Federal do Espírito Santo, 2018-03-29) Costa, Adriano Goldner; Fernandes, Valéria de Oliveira; Batitucci, Maria do Carmo Pimentel; Dias Junior, Camilo; Lo Monaco, Paola Alfonsa Vieira; Almeida, Stéfano Zorzal de
    Microalgae cultivation presents several applications of economic and environmental interest, such as obtaining compounds for human and animal food supplementation, waste water treatment and, more recently, the biofuels production. Studies with the light and temperature manipulation, as well as the use of agricultural effluents as alternative cultivation mediums, can make possible the increase of the microalgal biomass, reducing the production costs. In this study, the effects of different temperature conditions (25ºC, 30ºC and 35ºC) and luminosity (without shading, 50% shading and 70% shading) on the Desmodesmus communis growth and biomass were evaluated. Different agricultural effluents concentrations (residual hydroponic solution of lettuce culture and biodigested swine residue) were also tested as alternative means for the Scenedesmus acuminatus cultivation, in order to evaluate its biotechnological potential, to minimize productive costs and to mitigate environmental impacts. Three treatments with different concentrations of each effluent (20%, 30% and 40% of the hydroponic residue, and 10%, 15% and 20% of the swine effluent) and a control with ASM1 synthetic medium were established. Growth analyzes, dry biomass, a and b chlorophyll, total carotenoids, water soluble protein content, total carbohydrates and lipids, fatty acid methyl esters profile, and nutrient removal percentage and electrical conductivity reduction of the mediums were performed. In the experiments with different temperatures and shading, D. communis showed great tolerance to the variations tested (25-35ºC and up to 50% shading), showing no significant differences between growth parameters, dry biomass and a chlorophyll. However, under shading 70% the microalga presented significant limitation on maximum cell yield, dry mass and chlorophyll. In the tests with the use of residual hydroponic solution and biodigested swine effluent, S. acuminatus acted as an efficient bioremediation agent, significantly reducing the nitrogen and phosphorus concentrations of these residues (68,5-99,8%). The 40% hydroponic effluent culture was characterized by a microalgal biomass rich in proteins (44,2%), a and b chlorophyll (9799 µg.L-1 and 2730 µg.L-1 , respectively), carotenoids (4826 µg.L-1 ), besides fatty acids of great nutritional value, such as linolenic acid (19,5%), suggesting its use as a human and animal food supplement. The microalgae cultivation in swine effluent after biodigestion showed low efficiency in terms of productivity and useful biomass, being unviable to algal growth in concentrations higher than 10% residue. For the two evaluated effluents, the fatty acid methyl esters total content presented low yield (20,1-64,3 mg.g-1 ), which compromises their application in the industry for the biodiesel production. On the other hand, the high carbohydrate content in crops with 20% and 30% hydroponic effluent (44,1 and 34,4%, respectively), suggest its use in the bioethanol production. Based on the results, it was concluded that D. communis showed to be tolerant to variations in light and temperature, showing potential to be cultivated on a larger scale, and S. acuminatus showed high efficiency in the bioremediation of the tested agricultural effluents. In addition, in the cultures with residual hydroponic solution, it was possible to produce a microalgal biomass with great biotechnological potential.
  • Nenhuma Miniatura disponível
    Item
    Potencial bioestimulante do extrato de microalgas na germinação e crescimento de culturas agrícolas
    (Universidade Federal do Espírito Santo, 2022-10-05) Santos, Nair Hildelgard Soares dos; Machado, Levi Pompermayer; https://orcid.org/; http://lattes.cnpq.br/; Co-orientador2; https://orcid.org/; http://lattes.cnpq.br/; Co-orientador3; https://orcid.org/; http://lattes.cnpq.br/; Co-orientador4; ID do co-orientador4; Lattes do co-orientador4; Fernandes, Valéria de Oliveira ; https://orcid.org/; http://lattes.cnpq.br/; Orientador2; https://orcid.org/; http://lattes.cnpq.br/; https://orcid.org/; http://lattes.cnpq.br/; Corte, Viviana Borges ; https://orcid.org/; http://lattes.cnpq.br/; Almeida, Stéfano Zorzal de ; https://orcid.org/; http://lattes.cnpq.br/; Alves, Fernanda Brêda ; https://orcid.org/; http://lattes.cnpq.br/; Dutra, Jean Carlos Vencioneck ; http://lattes.cnpq.br/; 5º membro da banca; https://orcid.org/; http://lattes.cnpq.br/; 6º membro da banca; https://orcid.org/; http://lattes.cnpq.br/; 7º membro da banca; https://orcid.org/; http://lattes.cnpq.br/
    Currently the global demographic pressure on agricultural production requires new and sustainable approaches to meet the growing demand for plant biomass for human feed, animal feed and energy production. Therefore, there has been growing interest in natural biostimulant substances in agriculture due to the challenge of balancing technological development with environmental conservation. Microalgae have several biotechnological applications, including biostimulants. In modern agriculture, microalgae are an ecologically correct option to replace chemical fertilizers, as they can be used as biostimulants, soil modifiers and food additives. The objective of this work was to evaluate the effects of the application of microalgae extracts on the germination and growth of bean (Phaseolus vulgaris L.), corn (Zea mays L.) and papaya (Carica papaya L.) crops. It was possible to evidence that aqueous extracts obtained from microalgae presented biostimulating growth potential, considering that all seeds used in this study showed positive germ responses. It is noteworthy that most seeds obtained higher germination values, mean time, good speed indices, and better initial performance when submitted to extracts of species of the genus Chlorella, mainly at concentrations 1.0 g/L and 1.5 g/L. For the growth experiment, Scenedesmus acuminatus extract showed efficacy in stimulating the growth of bean plants, considering that plants submitted to this extract obtained higher grain yield per plant and higher number of pods. Thus, it can be affirmed that the biostimulant, when applied by foliar, is capable of promoting the transport of photoassimilates for the seeds, which would result in greater accumulation of mass in the seeds. It is also possible to attribute the positive effect of S. acuminatus extract on the yield and productivity of the bean crop to the availability of micronutrients present in this microalgae. It is necessary to highlight that to evaluate the action of extracts produced from algae, one should consider the agricultural crop to be tested, and concentrations. Because the seeds may present a different physiology and this influences the mechanism of action of the extracts, consequently presenting different responses from those obtained in this study. From the results it is possible to attribute the importance of microalgae in the agricultural sector, for its potential for the development of new biostimulating products of plant growth
  • Nenhuma Miniatura disponível
    Item
    Uso de extratos vegetais para o controle de fungos em sementes crioulas
    (Universidade Federal do Espírito Santo, 2023-02-24) Lima, Juliana Trindade; França, Hildegardo Seibert; https://orcid.org/0000-0001-6129-8793; http://lattes.cnpq.br/1284874997224988; http://lattes.cnpq.br/9522158171520275; Corte, Viviana Borges; https://orcid.org/0000000254886578; http://lattes.cnpq.br/3694434981958328; Almeida, Stéfano Zorzal de; https://orcid.org/0000-0002-9977-5898; http://lattes.cnpq.br/3680096174839424; Dutra, Jean Carlos Vencioneck; https://orcid.org/0000-0003-3893-9470; http://lattes.cnpq.br/4101176432227035; Silva, Leonardo Faria
    Creole seeds can be defined as those traditional varieties of plants cultivated and adapted to the places where they have developed for many years. They constitute an important way of recovering and preserving the genetic base of many species of cultivated plants. Precarious storage conditions in agroecological crops can contribute to the occurrence of several fungi that infest native seeds. These organisms are able to promote faster deterioration of harvested seeds and affect their germination, so farmers resort to improved seeds and/or seeds treated with chemical fungicides, putting the survival of this genetic heritage stored in vivo at risk. Extensive and repeated application of these synthetic agrochemicals can lead to negative effects such as resistant fungi, environmental and non-target organism contamination. Therefore, they create an impetus for the search for alternative control measures that are naturally safe, such as plant extracts with antifungal potential. Aroeira extracts (Schinus terebinthifolia Raddi) and clove basil (Ocimum gratissimum L.) have demonstrated an inhibitory effect on the growth of post-harvest fungi. Thus, the objective was to evaluate the effects of plant extracts on fungal control and on the physiological quality of native bean and corn seeds before and after storage. Mastic and clove basil leaves were collected at the Reginaldo Conde Agricultural Engineer Experimental Farm (FERC) at the Capixaba Institute for Research, Technical Assistance and Rural Extension (INCAPER), Viana, ES. The ethanolic extracts were obtained by maceration in ethanol and subsequent fractionation with solvents of increasing polarity (hexane, dichloromethane, ethyl acetate and butanol). Ethanol extracts and their respective fractions of increasing polarity of leaves of both plants were investigated for chemical composition, in vitro antioxidant and antifungal activity on fungi associated with creole seeds during storage. The ethanolic extract and the dichloromethane fraction of both plants showed the best results for inhibiting the in vitro fungal growth of Aspergillus sp. and Rhizopus sp. The butanol fraction of aroeira showed the highest antioxidant capacity, as in clove basil the ethanolic extract had this effect more pronounced. In view of the antifungal results, clove clove extracts were more active against the fungi tested. Seeds were purchased from the Instituto Federal of Espírito Santo seed bank, campus Santa Teresa, ES. The seeds were submitted to ethanolic extract and dichloromethane fraction of clove basil leaves and eugenol nanoemulsion and stored in plastic containers at room temperature. The sanity and germination test of the seeds was carried out, in the pre and post storage. The fungi found in the seeds are of the genera Aspergillus, Penicillium and Rhizopus. In bean seeds, treatment with eugenol nanoemulsion was more effective in reducing the incidence of pathogens, on the other hand, in corn seeds, ethanolic extract and dichloromethane fraction were more active. The dichloromethane fraction and the eugenol nanoemulsion negatively affected the seed vigor of both crops. The results indicate potential use of O. gratissimum extracts in the preservation of stored seeds.
  • Nenhuma Miniatura disponível
    Item
    Utilização da vinhaça no cultivo da microalga Klebsormidium flaccidum (Kützing) Silva visando à produção de Biomassa aplicada ao mercado de biodiesel
    (Universidade Federal do Espírito Santo, 2019-02-22) Guarieiro, Mayara dos Santos; Fernandes, Valéria de Oliveira; Almeida, Stéfano Zorzal de; Lo Monaco, Paola Alfonsa Vieira
    The microalgae are able to supply large amounts of biomass rich in biocides of commercial interest and their use in the biofuel market is a promising alternative. However, it’s important to have the cost of the crops, requiring a search for alternatives that aim to make the costs of the process, aiming at large-scale production. The use of industrial waste is a strategy to reduce production costs through a use of available resources. The objective of this work was to reuse food as a source of nutrients for microalgae and flacidium as an alternative for the production of biofuels. For this purpose, the vineyard, the residual water of the sugarcane distillation process, was used. The experiments were carried out in the room of cultivation of the Laboratory of Taxonomy and Ecology of Continental Algae - Federal University of Espírito Santo (UFES). The analysis was carried out to follow the growth and development of the culture grown in three different types of wine (10%, 20% and 30%) diluted in distilled water. In terms of cell density, the results were observed in the treatments with 20% (1.3 x 10 cel.mL-1) and a biomass presented results at 20 and 30% dilution. In relation to the biochemical characterization of the biomass produced, the protein and lipid content decreased as the vinasse concentration increased in the media. Thus, the use of the biomass produced by the crop is not intended to optimize another use that is not a biodiesel production. In contrast, a biomass was rich in carbohydrates, which suggests its application as a potential material for the production of bioethanol. The cultivation of K. flaccidum in vinasse still demonstrates nutrient efficiency, such as ammoniacal nitrogen and orthophosphate, with removal percentages of 97.27% and 40.17% respectively, thus reducing the pollutant load of the vinasse, thus minimizing environmental impacts. Considering the results obtained, the cultivation of K. flaccidum microalgae in vinasse can be an alternative to the sustainable and low cost development for the production of biomass to the market of biofuels linked to the treatment of waste water.