Abstract A large collection of coffee genetic resources is conserved in Costa Rica. In this study, microsatellite DNA fingerprinting of coffee through singleplex and multiplex PCR approaches coupled with capillary electrophoresis are described. To validate both methods, germplasm of Coffea spp. (Arabica and non-Arabica) and intraspecific F1 hybrids were analyzed using fourteen microsatellite markers. It was observed that through both PCR methods the fingerprinting profile of a subset of samples was identical. The genetic analyses revealed that non-Arabica coffee displayed greater genetic variation than Arabica coffee did. In addition, microsatellite analyses allowed the separation of C. arabica from other species using the principal coordinate analysis (PCoA) approach. The neighbor-joining tree clustering analysis revealed either a grouping of wild genotypes separated from cultivars of C. arabica, or a relation of intraspecific F1 hybrids with parental lines. The utility of our methodology for the characterization of F1 hybrids not previously analyzed through SSR (Simple Sequence Repeats) fingerprinting is demonstrated.

Abstract Most commercial papaya varieties segregate hermaphrodite and female plants. Growers normally select hermaphrodite plants in the field, due to market preferences. This requires planting multiple plants per site and later thinning of the females, distinguished by flower bud inspection. Micropropagation or the use of molecular markers are two possibilities to grow only hermaphrodite plants. Under the tropical conditions of this study, the field performance of hermaphrodite papaya plants developed by both of these methods was described. Moreover, a multiplex qPCR reaction was optimized. Hermaphrodite seedlings selected by molecular markers and plants obtained by micropropagation, had a lower slenderness ratio and initiated fruit production at a lower height than those selected by the conventional practice of the orchard. An analysis of flower types between the sex determination methods indicated that growing one hermaphrodite papaya plant per hole reduces the percentage of female-sterile flowers, resulting in fruit set at a lower trunk height and higher yields.

El estudio fitoquímico de las partes aéreas de Amyris brenesii (Rutaceae) recolectadas en Río Cuarto, Grecia, Alajuela (Costa Rica) mostró la presencia de cuatro nuevos compuestos: la 6-hidroxi-6-O-(3-hidroximetil-3-metilalil)angelicina 1, el 6-(N-acetil-2-etanamin)-2,2-dimetil-2Hcromeno 2, el lignano 2,5-deshidrohinokinina 3 y la N-acetil-O-(geranil)-tiramina 4. Adicionalmente se aislaron los lignanos hinokinina 5, y justicidina E 6, las cumarinas escopoletina 7 y marmesina 8, el ácido 24-moretenoico 9 y el O-(3,3-dimetilalil)-halfordinol 10. Las separaciones se llevaron a cabo mediante la aplicación de técnicas cromatográficas y la elucidación de las estructuras se realizó con la ayuda de técnicas espectroscópicas de Resonancia Magnética Nuclear (RMN) de una y dos dimensiones.

Four new compounds from the non-polar extract of the plant Amyris brenesii (Rutaceae) from Costa Rica. Fractionation of a non polar extract of the aerial parts of Amyris brenesii collected in Río Cuarto, Grecia, Costa Rica has resulted in the isolation of four new compounds, 6-hidroxy-6-O-(3-hidroxymethyl-3methylalyl)-angelicin 1, 6-(N-acetyl-2-etanamin)-2,2-dimethyl-2H-cromen 2, the lignan 2,5-dehidrohinokinin 3 and N-acetyl-O-(geranyl)-tiramine 4. In addition, we isolated six previously known compounds: the lignans hinokinin 5 and Justicidin E 6, the coumarins scopoletin 7 and marmesin 8, 24-moretenoic acid 9, and the nitrogen compound O-(3,3-dimethylalyl)-halfordinol 10. All the separations were done with chromatographic techniques and the structures were elucidated by using 1D and 2D NMR techniques. Rev. Biol. Trop. 56 (3): 1043-1052. Epub 2008 September 30.

La cinética de la biodegradación de los ésteres metílicos y etílicos derivados de palma (biodiesel) por una población silvestre de bacterias aeróbicas fue medida a 20 °C, como medición manométrica del consumo de oxígeno. Los ésteres metílicos y etílicos se obtuvieron por transesterificación del aceite de palma con metanol y etanol,respectivamente. La flora bacteriana incluyó a los géneros Bacillus, Proteus, Pseudomonas, Citrobacter y Enterobacter. Las velocidades de consumo de oxígeno para las muestras de biodiesel fueron similares a lo observado en la biodegradación de disoluciones 1.0 mM de sustratos sencillos solubles en agua, tales como carbohidratos, aminoácidos y albúmina de huevo.

The kinetics of biodegradation of palm-derived fatty methyl and ethyl esters (Elaeis guineensis biodiesel) by a wild-type aerobic bacterial population was measured at 20 °C, as the rate of oxygen uptake by a manometric technique. The methyl and ethyl biodiesels were obtained by potassium-hydroxide catalysed transesterification of palm oil, respectively. The bacterial flora included the genera Bacillus, Proteus, Pseudomonas, Citrobacter and Enterobacter. The rate of oxygen uptake for palm biodiesel is similar to the quantity observed in the biodegradation of 1.0 mM solutions of simple substrates such as carbohydrates or amino acids.Palm methyl or ethyl biodiesel is subjected to facile aerobic biodegradation by wild-type bacteria commonly present in natural open environments. This result should lessen any environmental concern for its use as alternative fuel, solvent or lubricant. Rev. Biol. Trop. 54(1): 59-63.Epub 2006 Mar 31.