h i g h l i g h t sWe evaluate the effect of biodiesel on commercial rubber at molecular level. The new CMP-NMR probe was successful to study the phases in the fuel-rubber system. We observed that the biodiesel penetrates at EPDM despite the opposite report. It is observed the increasing on rubbers softening after biodiesel immersion. a b s t r a c t Biodiesel has been incorporated into the energy matrix in several countries, but its compatibility with some materials used in automotive engines is of growing concern. In the present study, comprehensive multiphase (CMP) NMR is applied to understand the different phases in fuel-rubber systems. CMP NMR is a novel technology that integrates all the hardware from solution-, gel-and solid-state into a single NMR probe, permitting all phases to be studied in samples in their natural unaltered state. Transverse relaxation experiments in combination with inverse diffusion editing permit the increasing mobility of the rubbers chains with biodiesel exposure to be monitored. Conversely diffusion editing and RADE experiments highlight the more rigid domains. In summary NR and NBR showed the absence of highly rigid domains after exposure to biodiesel whereas SBR and EPDM especially better retained their structural integrity. 13 C editing protocols and 13 C-1 H HSQC confirmed the increasing gel-like properties of NR, NBR and SBR with exposure to biodiesel. However, variable contact time experiments showed that biodiesel penetrates even the most resilient EPDM pores causing relaxation of the polymer chains and demonstrates that NMR is sensitive enough to highlight even the very slight swelling of the EPDM. Through these results it is possible to observe that the elastomer that exhibits the lowest susceptibility to biodiesel in molecular terms was EPDM, followed by SBR, NR, and NBR. It was also observed that biodiesel molecules were present in the EPDM structure despite the literature reporting its general resilience to biodiesel.

A great demand for prebiotics is driving the search for new sources of fructo-oligosaccharides (FOS) producers and for FOS with differentiated functionalities. In the present work, FOS production by a new isolated strain of Aspergillus ibericus was evaluated. The temperature of fermentation and initial pH were optimized in shaken flask to yield a maximal FOS production, through a central composite experimental design. FOS were produced in a one-step bioprocess using the whole cells of the microorganism. The model (R 2 = 0.918) predicted a yield of 0.56, experimentally 0.53 ± 0.03 g FOS .g initial sucrose −1 was obtained (37.0°C and a pH of 6.2). A yield of 0.64 ± 0.02 g FOS .g initial sucrose −1 was obtained in the bioreactor, at 38 h, with a content of 118 ± 4 g.L −1 in FOS and a purity of 56 ± 3%. The chemical structure of the FOS produced by A. ibericus was determined by HPLC and NMR. FOS were identified as 1-kestose, nystose, and 1 F-fructofuranosylnystose. In conclusion, A. ibericus was found to be a good alternative FOS producer. sucrose −1

A análise multivariada da composição química dos óleos essenciais das folhas de Eugenia uniflora com diferentes cores de fruto indicou a presença de três grupos de óleos em relação ao biótipo do fruto das amostras. O primeiro grupo incluiu amostras de frutos amarelos, vermelhos escuros e roxos contendo altas percentagens de germacreno B (11,1-30,7%), germacrona (9,8-54%) e atractilona (0-19,9%). No grupo II, com amostras de frutos vermelhos claro, os constituintes majoritários foram o curzereno (42,0-43,2%), germacreno D (8,7-9,0%) e germacreno A (5,9-8,9%), enquanto que o grupo III incluiu amostras com frutos vermelho-alaranjado, caracterizadas por um alto conteúdo de selina-1,3,7(11)-trien-8-ona (40,3-55,4%) e epóxido de selina-1,3,7(11)-trien-8-ona (12,7-24,4%). Os óleos essenciais foram investigados frente ao fungo Paracoccidioides brasiliensis pela técnica de macrodiluição em caldo. O resultado mais significativo foi obtido com o óleo do grupo II, com a forma leveduriforme de P. brasiliensis sendo inibida completamente na concentração de 62,5 mg mL -1 .The multivariate chemical analysis of essential oils of Eugenia uniflora leaves with different fruit colours indicated the presence of three oil clusters regarding sample biotypes. The first cluster included yellowish, dark red and purple fruits with high percentages of germacrene B (11.1-30.7%), germacrone (9.8-54%) and atractylone (0-19.9%). In cluster II, with bright red fruit samples, the major constituents were curzerene (42.0-43.2%), germacrene D (8.7-9.0%) and germacrene A (5.9-8.9%), whereas cluster III included red-orange fruit samples containing high contents of selina-1,3,7(11)-trien-8-one (40.3-55.4%) and selina-1,3,7(11)-trien-8-one epoxide (12.7-24.4%). The clustered oils were investigated against the systemic fungus Paracoccidioides brasiliensis via the broth macrodilution method. The oil from cluster II revealed the most significant result. The yeast form of P. brasiliensis was completely inhibited at a concentration of 62.5 mg mL -1 . Keywords: Eugenia uniflora, essential oil, chemical variability, antifungal activity, Paracoccidioides brasiliensis IntroductionFungal infections are common in tropical countries and may have a major impact on public health. Whereas the dermatophyte fungi group is of common occurrence, 1 the incidence of systemic infections due to Paracoccidioides brasiliensis (Splendore) Almeida has increased in the last two decades. 2 P. brasiliensis is an etiological agent of paracoccidioidomycosis, the most prevalent human systemic mycosis in Latin America, where up to 10 million individuals are estimated to be infected. 3 This thermally dimorphic fungus grows as a filamentous saprobe (mycelium) in the soil at 25 °C and as a multicelular parasitic form (yeast) in the host. The shift from the mycelial to the yeast form (36 °C) is crucial for the infection of the human host. The heat shock response of P. brasiliensis to an abrupt increase in environmental temperature during infection results in the expression of the heat shock...

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