ABSTRACT
ABSTRACT Saccharum spontaneum has been used for the development of energy cane a crop aimed to be used for the production of second-generation ethanol, or lignocellulosic ethanol. Lignin is a main challenge in the conversion of cell wall sugars into ethanol. In our studies to isolate the genes the lignin biosynthesis in S. spontaneum we have had great difficulty in RT-PCR reactions. Thus, we evaluated the effectiveness of different additives in the amplification of these genes. While COMT and CCoAOMT genes did not need any additives for other genes there was no amplification (HCT, F5H, 4CL and CCR) or the yield was very low (CAD and C4H). The application of supplementary cDNA was enough to overcome the non-specificity and low yield for C4H and C3H, while the addition of 0.04% BSA + 2% formamide was effective to amplify 4CL, CCR, F5H and CCR. HCT was amplified only by addition of 0.04% BSA + 2% formamide + 0.1 M trehalose and amplification of PAL was possible with addition of 2% of DMSO. Besides optimization of expression assays, the results show that additives can act independently or synergistically.
Subject(s)
Gene Expression Regulation, Plant/genetics , Reverse Transcriptase Polymerase Chain Reaction/methods , Nucleic Acid Amplification Techniques/methods , Saccharum/genetics , Cell Wall/genetics , DNA Primers , Ethanol , Lignin/biosynthesis , Lignin/genetics , Methyltransferases/geneticsABSTRACT
O chá preto é uma das bebidas mais consumidas no mundo. Essa bebida é feita a partir da infusão de folhas processadas de Camellia sinensis, que é cultivada em mais de 30 países, tendo grande importância socioeconômica. Estudos sugerem que o chá tem efeito protetor contra diversos tipos de câncer e doenças cardiovasculares devido à presença de polifenóis denominados catequinas, que são oxidadas enzimaticamente durante o processamento das folhas, gerando uma mistura constituída principalmente de teaflavinas, teasinensinas e tearubiginas. A produção mundial de chá tem aumentado mais do que o consumo, provocando redução do preço que, juntamente com o aumento no custo de produção, implica a necessidade de alta produtividade e qualidade. Apesar disso, ainda não foram estabelecidos critérios precisos e eficientes para predizer a qualidade do chá a partir das folhas, bem como quais práticas agronômicas contribuem para o aumento da qualidade. No Brasil, a cultura do chá se concentra no Vale do Ribeira, em São Paulo (SP), sendo quase toda produção exportada. Apesar de o produto brasileiro não ser de alta qualidade, tem conseguido bons preços no mercado internacional. A produção brasileira, a área de produção e o número de indústrias de chá vêm diminuindo ao longo dos últimos anos, o que demonstra a necessidade de investimentos.
Black tea is one of the most widely consumed beverages in the world and it is prepared by the infusion of water with processed leaves of Camellia sinensis, which is cultivated in more than 30 countries, assuming a great socioeconomic importance. Several studies suggest that tea has protective effects against cancer and cardiovascular disease, due to the presence of polyphenols called catechins, which are oxidized enzymatically during the processing of the black tea, generating a mixture consisting mainly of theaflavins, theasinensins and thearubigins. The world production of tea has increased more than the demand, causing a drop of the price which, together with the increase in cultivation costs has shown a need for high productivity and quality. Nevertheless, there is not yet an efficient and accurate criteria to predict the quality of tea and agronomic practices which contribute to the increase in quality. In Brazil, the culture of tea is concentrated in the Ribeira Valley - SP, and almost all the production is exported. Despite the Brazilian product is not of high quality, it has achieved good prices in the international market. The Brazilian production, the production area and the number of tea industries are decreasing in recent years, clearly indicating the need for investments.
ABSTRACT
A produção de rutina, quercetina, 1,5-diidroxixantona e ácido betulínico foi investigada em plântulas de H. brasiliense crescendo in vitro, sob a influência de ácido salicílico, polietilenoglicol, NaCl, 24-epibrassinolídeo, benzotiadiazole (BION), metiljasmonato e concentrações aumentadas de boro e nitrogênio no meio líquido de cultura. As avaliações foram feitas após 5 e 10 dias do início dos tratamentos. Os maiores aumentos de conteúdo foram observados com quercetina para boro e ácido salicílico aos 5 dias, e 24-epibrassinolídeo e BION aos 10 dias.
The production of rutin, quercetin, 1,5-dihydroxyxanthone and betulinic acid was investigated in plantlets of H. brasieliense in vitro, and exposed to salycilic acid, poliethylene glycol, NaCl, 24-epibrassinolide, benzothiadiazole (BION), methyljasmonate and increased concentrations of boron and nitrogen in the liquid culture medium. Evaluations of the contents were carried out after 5 and 10 days of treatments. The highest increase was observed in quercetin in the salycilic acid and B treatments after 5 days of exposure, and in 24-epibrassinolide and BION after 10 days.
Subject(s)
Quercetin , Rutin , XanthonesABSTRACT
Caffeine inheritance was investigated in F2 and BC1F1 generations between Coffea arabica var. Bourbon Vermelho (BV) and Coffea canephora var. Robusta 4x (R4x). The caffeine content of seeds and leaves was determined during 2004 and 2005. Microsatellite loci-markers were used to deduce the meiotic pattern of chromosome pairing of tetraploid interspecific hybrids. Genetic analysis indicated that caffeine content in seeds was quantitatively inherited and controlled by genes with additive effects. The estimates of broad-sense heritability of caffeine content in seeds were high for both generations. In coffee leaves, the caffeine content (BSH) from the same populations showed transgressive segregants with enhanced levels and high BSH. Segregation of loci-markers in BC1F1 populations showed that the ratios of the gametes genotype did not differ significantly from those expected assuming random associations and tetrasomic inheritance. The results confirm the existence of distinct mechanisms controlling the caffeine content in seeds and leaves, the gene exchange between the C. arabica BV and C. canephora R4x genomes and favorable conditions for improving caffeine content in this coffee population.
ABSTRACT
Terpenes are a very large and structurally diverse group of secondary metabolites which are abundant in many essential oils, resins and floral scents. Additionally, some terpenes have roles as phytoalexins in plant-pathogen relationships, allelopathic inhibitors in plant-plant interactions, or as airborne molecules of plant-herbivore multitrophic signaling. Thus the elucidation of the biochemistry and molecular genetics of terpenoid biosynthesis has paramount importance in any crop species. With this aim, we searched the CitEST database for clusters of expressed sequence tags (ESTs) coding for terpene synthases. Herein is a report on the identification and in silico characterization of 49 putative members of the terpene synthase family in diverse Citrus species. The expression patterns and the possible physiological roles of the identified sequences are also discussed.
ABSTRACT
Although the popularity of coffee as beverages is due ti the alertness caused by caffeine, there is an increasing market for decaffeinated coffee. Attempts of interspecific crosses have been made at the Instituto Agronômico de Campinas as a strategy to reduce caffeine in coffee seeds. In addition to the reduced number of individuals in the F1 progenies, very few were considered promising to be used in a breeding program. Here we present the results of analyses of the caffeine content in seeds of several coffee species which might be used in new interspecific crosses.