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Caracterização fisiológica, bioquímica e molecular da germinação de sementes de mamona (Ricinus communis L.) sob estresses salino e osmótico

2024-02-19T13:23:52Z

Título: Caracterização fisiológica, bioquímica e molecular da germinação de sementes de mamona (Ricinus communis L.) sob estresses salino e osmótico Autor(es): Cunha, Diego da Silva Primeiro Orientador: Castro, Renato Delmondez de Abstract: Ricinus communis L. (Euphorbiaceae), known as castor, is a species that stands out in the national and international scenario for the oil extracted from its seeds which is widely demanded by by the global bioindustries. In addition to its multiple commercial and bioindustrial uses, it has socioeconomic importance in the semiarid regions of Brazil and global wide. However, semiarid regions have adverse environmental conditions such as short periods of rain and soils with saline levels. Conditions that limit water absorption and promote greater generation of reactive oxygen species (ROS), such as superoxide anion-O2, hydroperoxyl-HO2 radical, hydroxyl-OH radical, hydrogen peroxide-H2O2 and singlet oxygen, 1O2, compromising the germinative processes, growth, and development of seedlings, reduce productivity and can lead to plant death. During the germination process, the activity of ROS removing enzymes has been reported, such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX), among others, which constitute efficient detoxification mechanisms during imbibition, these enzymes can be used as molecular markers to elucidate the events that occur during the germination process. Therefore, this proposal provides a better understanding of the mechanisms involved in the response of castor beans to abiotic stresses by water restriction and saline conditions at the physiological level, related to antioxidant enzymes by means of biochemical and molecular studies. A REVIEW was developed where studies were identified on advances in research related to the cultivation of castor under abiotic stresses due to water restriction and salt stress, germination, and early stages of development of seedlings and antioxidant enzymes, shighlighting the enzymes superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). In CHAPTER 1, we performed the biometric characterization of two R. communis cultivars (BRS Nordestina and BRS Paraguaçu), we noticed that the seeds of Cultivar BRS Paraguaçu are larger than those of BRS Nordestina, which may be related to the higher water absorption observed for the seeds of that cultivar. Through the imbibition studies in osmotic water restriction (PEG) and salinity (NaCl), we observed that there is a difference in the water restriction capacity for these two solutions at the same osmotic potential, where for the imbibition by PEG at -0.23 MPa there was a drastic decrease in water absorption, inhibiting the cell cycle and the germination process while in the same osmoticum by NaCl imbibition there was only a slight delay in water absorption compared to the control. The imbibition in light potentials of NaCl (-0.23 MPa) stimulated a greater activity of the antioxidant enzyme SOD, while for the imbibition in PEG due to severe water restriction, the activity of the SOD enzyme was lower than the control. In CHAPTER 2, we performed the characterization of the family of 6 putative RcAPX genes that code for the enzyme Ascorbate peroxidase (APX) in castor beans, , through phylogenetic analysis we identified the orthologous genes in other angiosperms where we classified the APX genes according to location intracellular (citosol, plastid and peroxisomes). We observed that the RcAPX genes have a large number of exons/introns in addition to sharing conserved motifs. An increase in the total activity of the APX enzyme was observed after 48 h of imbibition (post-germinative) in the imbibition of water (control) and in NaCl -0.23 MPa (saline restriction) in both cultivars evaluated, while that imbibition in a -0.23 MPa PEG repressed the activity of APX. In CHAPTER 3, we identified and characterized 2 putative RcCAT genes representing the Catalase (CAT) gene family in Castor beans, predicted for peroxisome intracellular localization, from phylogenetic comparison we found orthologous genes in other angiosperms where we observed the classification into three groups. We found differences in gene structure and motif order for the RcCAT2 gene compared to the angiosperm CAT genes. Through the analysis of regulatory elements in the promoter region of these genes, we identified possible forms of regulation related to biotic and abiotic stresses, as well as plant hormones such as ABA. Finally, the enzymatic activity of catalase was shown to be modulated according to development time, stress during germination and respective genotype. The results herein contribute to a better understanding of the effects of water and saline restriction stresses in castor beans, in addition to the characterization of a family of genes that code for important antioxidant enzymes in seed responses to abiotic stress conditions. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Tese

Caracterização química e biológica de extratos de própolis vermelha do nordeste do Brasil obtidos por diferentes métodos de extração

2022-05-14T07:22:04Z

Título: Caracterização química e biológica de extratos de própolis vermelha do nordeste do Brasil obtidos por diferentes métodos de extração Autor(es): Reis, João Henrique de Oliveira Primeiro Orientador: Druzian, Janice Izabel Abstract: Propolis is a natural compound of wide application in the food, pharmaceutical and cosmetic areas, being a complex resin produced by bees through the mixture of exudates from different plants, wax and salivary secretions. Variations in the chemical composition, and consequently, in the biological activity of propolis extracts, are associated with many factors, such as type, geographic origin, seasonality, among others. Within this context, the objective of this study was to evaluate the influence of different extraction methods on the chemical and biological composition of red propolis extracts from different geographic origins, as well as to determine the process conditions for obtaining red propolis extracts using the technology extraction with supercritical fluid (SFE). Initially, conventional (ethanolic) and ultrasound-assisted extraction methods were used to extract active compounds from propolis from different regions of Northeastern Brazil (Sergipe, Alagoas, Bahia, and Rio Grande do Norte). Contents of phenolic compounds, flavonoids, in vitro antioxidant activity, concentration of markers (formononetin and kaempferol) and cytotoxicity to human tumor cell lines (HCT116 - human colon, HL60 - leukemia, PC3 - carcinoma of prostate and SNB19 - glioblastoma) were evaluated comparatively for the twelve extracts obtained from six different samples. Additionally, red propolis extracts were obtained by SFE from a sample from Alagoas using different process conditions. To determine the process parameters applying SFE, the Overall Extraction Curves (OEC - Overall Extraction Curves), the S/F (CO2 mass/propolis mass), the percentage of co-solvent (ethanol – 0, 1, 2 and 4%) and the global yield isotherms (GYI - Global Yield Isotherms) as a function of different pressures (250, 350 and 450 bar) and temperatures (31.7, 40 and 50°C). The total phenolic compounds, antioxidant activity and the content of formononetin, naringenin and kaempferol in the extracts obtained under different conditions (SFE) were investigated. As a result of this study, significant variations (p>0.05) were identified in the content of the compounds investigated in red propolis extracts, confirming that the chemical composition varies according to the region where the samples were collected. The highest concentration of the compounds of interest and the highest in vitro antioxidant activity were shown by extracts obtained from samples from the state of Alagoas (A1, A2, B1 and B2), which is currently the only one in Brazil that has certification of origin. The biomarkers formononetin and kaempferol were identified in all samples, regardless of origin or extraction method used. The highest concentrations of formononetin were identified in the extracts obtained by ultrasound, indicating a greater selectivity for the extraction of this compound by this method. Regarding cytotoxic activity, for the HCT-116 strain, all extracts showed inhibition greater than 90%, while for the HL-60 and PC3 strains, the lowest inhibition identified was 80%. In general, there was no significant difference (p>0.05) in the antiproliferative potential when comparing the extraction methods. The results showed that the composition of Brazilian red propolis varies significantly depending on the geographic origin and that the method used influences the resulting compounds that are present in the propolis. Regarding the application of SFE as an extractive method, within the parameters investigated, the best conditions found were a S/F of 131 and the use of ethanol in the highest concentration (4%), which resulted in higher yields of extract and higher content of antioxidant compounds. Formononetin, the main biomarker of red propolis, was the compound found in greater amounts in the extracts obtained by SFE under all conditions used. As expected, the temperature and pressure conditions also influenced the process yield, with 350 bar and 40°C being the best conditions for obtaining bioactive compounds from a red propolis sample. The new results for red propolis found in this study show that it is possible to obtain extracts with high antioxidant potential using alternative technologies, as well as that the geographic origin, the type of method used and the process conditions influence the quality of the extract obtained. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Tese

Desenvolvimento de sistemas biocompósitos baseados em polímeros biodegradáveis para liberação controlada do feromônio rincoforol

2022-05-14T07:22:06Z

Título: Desenvolvimento de sistemas biocompósitos baseados em polímeros biodegradáveis para liberação controlada do feromônio rincoforol Autor(es): Correia, Paulo Romano Cruz Primeiro Orientador: Druzian, Janice Izabel Abstract: Cantophorol (2-methyl-5 (E) heptene-4-ol) is the largest constituent of the male aggregation pheromone of Rhynchophorus palmarum L. (Coleoptera: Curculionity), a beetle that attacks several palm species and is the main vector. of the nematode Bursaphelenchus cocophylus, causative agent of red ring disease. In Brazil, this beetle mainly attacks the coconut the oil palm and acai tree, crops of great economic relevance. The use of traps containing pheromone baits has been increasingly employed in pest control in agriculture. For its application a constant release of the active is required during the insect capture period. Cantophorol has been used in eppendorf-type baits with a hole in the lid to control the beetle population. However, the validity of these baits depends on the evaporation rate of rincophorol through the device, which releases excessive amount of pheromone. The aim of the study was to develop a system in which the pheromone is diffusely and controlled released through the zeolite Y, activated carbon, starch and poly (butylene adipate co-terephthalate), PBAT activated carbon at 20 membranes. % produced by extrusion. Permeation studies of rincophorol across Y zeolite, activated carbon and starch membranes and pellets showed lower pheromone release rates compared to commercially available systems. Thus, they provided increased pheromone life, possibly resulting in lower cost of baits for the farmer and lower environmental impact. The studies carried out in this work allowed to select the activated carbon PBAT membrane, with great commercial potential, as a releasing device of cantoophorol for an extended period allowing greater protection to the pheromone in relation to the physical and chemical factors. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Tese

Análise da efetividade da hemolaserterapia para prevenção da sintomatologia dolorosa, alterações hematológicas e impacto na qualidade de vida em pacientes com anemia falciforme

2022-04-02T07:20:10Z

Título: Análise da efetividade da hemolaserterapia para prevenção da sintomatologia dolorosa, alterações hematológicas e impacto na qualidade de vida em pacientes com anemia falciforme Autor(es): Conceição, Sabrina Barbosa Matos da Primeiro Orientador: Cangussu, Maria Cristina Teixeira Abstract: Sickle cell anemia is one of the most common genetic diseases in Brazil, it is severe and its main clinical manifestations are painful crises and infection. An experimental study was carried out with the aim of evaluating the effectiveness of Laser Therapy (ILIB) in a follow-up service for patients with this disease in preventing these symptoms. The study included 81 individuals (21 cases/60 controls) with sickle cell anemia, over 12 years of age with body weight greater than or equal to 40 kg, who were receiving treatment at the Blood Center of Bahia in the period from October 2019 to March 2020 A clinical and laboratory examination and a semi-structured interview were conducted to obtain sociodemographic and clinical data. To assess quality of life, the WHOQOL-BREF was used before and after “Intravascular Laser Irradiation of Blood” (ILIB) laser therapy. The study was approved by the ethics committee - CAEE 16676619. 7. 1001.5013. Of the participants, 21 of the cases underwent laser therapy for 10 consecutive days and the care plan (interviews for the diagnosis, development of the care process and assessment of quality of life), and another 60 (control group) participated exclusively in the intervention of the care plan care. There was a significant difference between groups. ILIB contributed to improved sleep (p<0.0001) and decreased pain crises (p value <0.0355). There was no statistically significant difference in laboratory tests before and after ILIB in the case-assessed group. Regarding quality of life, there was an improvement in the psychological domain of the WHOQOL-BREF (p-value =0.001) between the case and control groups, with changes in life practices that intensified self-care and well-being. The intervention proved to be an adjunct in the treatment of sickle cell anemia, contributing to the prevention of painful symptoms and helping to improve quality of life. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Tese