Brazilian Archives of Biology and Technology
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/12090
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Item Evaluation of arsenic and selenium in brazilian soluble coffee by inductively coupled plasma atomic emission spectrometry with hydride generation(Instituto de Tecnologia do Paraná - Tecpar, 2001-10) Santos, Éder José dos; Oliveira, Elisabeth deA method for the evaluation of arsenic and selenium in soluble coffee by inductively coupled plasma atomic emission spectrometry with continuous hydride generation to attend the Brazilian food legislation is described. Samples were digested with nitric acid and hydrogen peroxide in a focused microwave system. Slow heating eliminated nitric acid and selenium (VI) was reduced to selenium (IV) by addition of 6 mol/L hydrochloric acid and heating at 90°C under a reflux system. The influence of sample acidity on sensitivity was investigated. Hydrochloric acid 6 mol/L was the most suitable reaction medium. Practical detection limits of 2.0μg/L for As and 1.0μg/L for Se were achieved and attended the Brazilian food legislation. The results of recoveries on spiked samples demonstrate the reliability and accuracy of the procedure.Item Compositional changes of proteins and amino acids in germinating coffee seeds(Instituto de Tecnologia do Paraná - Tecpar, 2000-07) Shimizu, Milton Massao; Mazzafera, PauloEndosperm is the main reserve tissue in coffee seeds. Coffee (Coffea arabica L.) seeds were germinated for six weeks and qualitative and quantitative changes in amino acids and proteins were investigated. The total content of free amino acids were reduced during germination, however, protein content remained constant. SDS-PAGE profiles showed that legumin-like proteins became less stained in the last weeks. Asparagine, glutamic acid, aspartic acid, alanine and lysine were the major free amino acids, although serine and glutamine were also significant. Except for tyrosine, which increased with germination, all other amino acids were reduced. Analysis of the amino acid composition of the total soluble protein showed glutamic acid/glutamine and glycine as the main amino acids. However, other amino acids such as leucine, aspartic acid/asparagine, alanine, lysine, serine were also found in reasonable amounts.Item Influence of coffee pruning on the severity of frost damage(Instituto de Tecnologia do Paraná - Tecpar, 2000-03) Androcioli Filho, Armando; Caramori, Paulo HenriqueFrost damages in a field experiment of pruning types and systems for the cultivars of Coffea arabica Catuaí and Mundo Novo, were evaluated at Londrina (23 o 22’S, 52 o 10 ́W), State of Parana, southern Brazil, during the winter of 1990 and 1994. Pruning types evaluated were ‘esqueletamento’ (cutting off all plagiotropic branches at 20-30 cm from the orthotropic branch), ‘decote’ (cutting off the orthotropic branch at 1.5 m and 2.0 m above ground) and ‘recepa’ (cutting off the orthotropic branch at 0.8 m above ground), performed on all rows and on alternate rows, and on different sections of the plant. Results indicated that frost damage could increase according to the type and height of pruning. The pruning type ‘esqueletamento’ and prunings at higher levels were more suitable for regions with frost risk. Under severe frost condition, pruning type did not affect the damage in anyone of the treatments evaluated.Item Production of extracellular protease by a brazilian strain of Beauveria bassiana reactivated on coffee berry borer, Hypothenemus hampei(Instituto de Tecnologia do Paraná - Tecpar, 2007-03) Ito, Eliana Tiemi; Pereira, Geni Varéa-; Miyagui, Dalva Tomoe; Pinotti, Maria Helena Pimenta; Neves, Pedro Manoel Oliveira JaneiroStudies were carried out on extracellular protease production by Beauveria bassiana CG432 in liquid medium containing glucose and yeast extract. B. Bassiana presented active growth after lag period of 24 h., produced 80% of the total of the extracellular protease activity in 48 h which was maximum on the 5 th culture day. The extracellular protease presented optimum activity at 60 o C, was stable up to 1M Cl - , maintained the stability during 15 day at 4 o C and -18 o C, but was not stable if frozen repeatedly.Item Genetic diversity among forty coffee varieties assessed by rapd markers associated with restriction digestion(Instituto de Tecnologia do Paraná - Tecpar, 2005-07) Diniz, Leandro Eugênio Cardamoni; Ruas, Claudete de Fátima; Carvalho, Valdemar de Paula; Torres, Fabrício Medeiros; Ruas, Eduardo Augusto; Santos, Melissa de Oliveira; Sera, Tumoru; Ruas, Paulo MaurícioThe genetic variability of 40 accessions of C. arabica was evaluated using a combination of the random amplified polymorphic DNA (RAPD) technique and restriction digestion of genomic DNA. The genetic variability and the relatedness among all accessions were initially evaluated using 195 RAPD primers which revealed a very low level of genetic variation. To improve the efficiency in the detection of polymorphism, the genomic DNA of all accessions were submitted to digestion with restriction endonucleases prior to PCR amplification. A total of 24 primers combined with restriction digestion of DNA rendered 318 bands, of which 266 (83.65%) were polymorphic. The associations among genotypes were estimated using UPGMA-clustering analysis. The accessions were properly clustered according to pedigree and agronomic features. The ability to distinguish among coffee accessions was greater for RAPD plus restriction digestion than for RAPD alone, providing evidences that the combination of the techniques was very efficient for the estimation of genetic relationship among C. arabica genotypes.Item Genetic variability for frost resistance among coffea accessions assessed in the field and in a cold chamber(Instituto de Tecnologia do Paraná - Tecpar, 2005-01) Petek, Marcos Rafael; Sera, Tumoru; Alteia, Marcos ZorzenonThe genetic variability for frost resistance was evaluated in field conditions and cold chamber among Coffea accessions. Results showed that C. liberica var. dewevrei and C. racemosa, as well as hybrids obtained from these species were more resistant to frost. There was a great genetic variability for frost resistance among the evaluated sources (b 2 = 0,98). The correlation estimated between damages in the field and in the cold chamber was 0.933**, therefore, this methodology was efficient and feasible and could be potentially used in a breeding program.Item An overview on molecular markers for detection of ochratoxigenic fungi in coffee beans(Instituto de Tecnologia do Paraná - Tecpar, 2009-11) Fungaro, Maria Helena Pelegrinelli; Sartori, DanieleOchratoxin A (OTA) is one of the most abundant food-contaminating mycotoxins. Its occurrence in several agricultural commodities has been considered a worldwide problem. This toxin is mainly produced by Aspergillus species. OTA has nephrotoxic, immunosuppressive, and carcinogenic effects and consequently the contamination with this toxin represents a high risk for human and animal health. In the last 5 years, several investigators have applied molecular methods in order to develop PCR assays for identifying and quantifying OTA-producing fungi in coffee beans samples. The main objective is to allow the detection of microorganisms capable of producing OTA, preferentially prior to ochratoxin production and accumulation. In this contribution several of these attempts will be reviewed and discussed.Item Resistance to leaf rust in coffee carrying SH3 gene and others SH genes(Instituto de Tecnologia do Paraná - Tecpar, 2007-09) Sera, Gustavo Hiroshi; Sera, Tumoru; Ito, Dhalton Shiguer; Azevedo, José Alves de; Mata, João Siqueira da; Dói, Deisy Saori; Ribeiro Filho, Claudionor; Kanayama, Fabio SeidiThe aim of this work was to evaluate the resistance to rust in coffee carrying SH3 gene and other SH genes. Twenty one CIFC’s coffee trees with several resistance genes SH were evaluated in field conditions. All the evaluated coffees carrying SH3 gene presented resistance to the rust. It was possible that rust races with the virulence gene v3 in the Paraná State didn’t exist. The SH3 gene in combination with genes SH5, SH6, SH7, SH8, SH9 and SH? would be very important to obtain cultivars with more durable resistance to the rust.Item Selection for durable resistance to leaf rust using test-crosses on IAPAR-59 and Tupi IAC 1669-33 cultivars of Coffea arabica(Instituto de Tecnologia do Paraná - Tecpar, 2007-07) Sera, Gustavo Hiroshi; Sera, Tumoru; Ito, Dhalton Shiguer; Azevedo, José Alves de; Mata, João Siqueira da; Doi, Deisy Saori; Ribeiro Filho, ClaudionorThe aim of this study was to identify plants of the IAPAR-59 and Tupi IAC 1669-33 coffee cultivars with less defeated resistance genes by the rust races present at IAPAR (Londrina, Paraná State, Brazil) using test-crosses. Eighteen test-crosses derived from hybridizations between ‘IAPAR-59’ or ‘Tupi IAC 1669-33’ with susceptible coffee to the rust disease were evaluated. Six hybrids were used as susceptible standards originated from hybridizations between two susceptible coffee plants. Many parental plants of the ‘IAPAR-59’ and ‘Tupi IAC 1669- 33’ presented more defeated resistance genes against rust races present at IAPAR than others of these cultivars or the genes were in heterozygous, because of segregant susceptible plants observed in some test-crosses. The test- crosses were very efficient to identify plants with less defeated resistance genes to the H. vastatrix. Coffee plants considered resistants would must be made test-crosses to verify which plants presented less and/or more defeated genes in homozygous.Item Production of herbicide-resistant coffee plants (Coffea canephora P.) via Agrobacterium tumefaciens-mediated transformation(Instituto de Tecnologia do Paraná - Tecpar, 2006-01) Ribas, Alessandra Ferreira; Kobayashi, Adilson Kenji; Pereira, Luiz Filipe Protasio; Vieira, Luiz Gonzaga EstevesTransgenic plants of Coffea canephora P. resistant to the herbicide ammonium glufosinate were regenerated from leaf explants after co-culture with Agrobacterium tumefaciens strain EHA105 harboring pCambia3301, a plasmid that contains the bar and the uidA genes both under control of 35S promoter. Direct somatic embryogenesis was induced on basal medium contained 1⁄4 strength macro salts and half strength micro salts of MS medium, organic constituents of B 5 medium and 30 g.L -1 sucrose supplemented with 5 μ M N 6 – (2-isopentenyl)-adenine (2-iP). Ten μ M ammonium glufosinate was used for putative transgenic somatic embryos selection. Presence and integration of the bar gene were confirmed by PCR and Southern blot analysis. Selected transgenic coffee plants sprayed with up to 1600 mg.L -1 of Finale , a herbicide containing glufosinate as the active ingredient, retained their pigmentation and continued to grow normally during ex vitro acclimation.