Literature on hydrocarbon degradation in extreme hypersaline media presents studies that point to a negative effect of salinity increase on hydrocarbonoclastic activity, while several others report an opposite tendency. Based on information available in the literature, we present a discussion on the reasons that justify these contrary results. Despite the fact that microbial ability to metabolize hydrocarbons is found in extreme hypersaline media, indeed some factors are critical for the occurrence of hydrocarbon degradation in such environments. How these factors affect hydrocarbon degradation and their implications for the assessment of hydrocarbon biodegradation in hypersaline environments are presented in this review.

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A estrutura ontogenética e espacial de dez espécies de palmeiras que ocorrem na Serra do Mar, Ubatuba, São Paulo, foi analisada nas fitofisionomias: Floresta Ombrófila Densa de Terras Baixas, Submontana e Montana. Em 12 parcelas de um hectare (quatro parcelas em cada fitofisionomia) foram instaladas três transecções de 10 × 100 m, subdivididas em subparcelas de 10 × 10 m, totalizando 0,3 hectares inventariados em cada parcela. Foram procedidas identificação e biometria completa de todas as palmeiras, e a distribuição espacial das populações foi analisada por meio do Índice de agregação (Ia) proposto por Perry. Com a elevação, foram observadas alterações na riqueza e abundância das espécies, com predominância de plântulas em Astrocaryum aculeatissimum, Euterpe edulis, Geonoma gamiova, Geonoma pohliana e Syagrus pseudococos. Indivíduos jovens apresentaram maior frequência em Attalea dubia, Bactris hatschbachii e Geonoma schottiana. Geonoma elegans apresentou mais adultos e Bactris setosa, frequências similares de plântulas e jovens. A maioria dos estádios ontogenéticos não foi correlacionada com a altitude e o padrão agregado foi predominante nas espécies de palmeiras. Dessa forma, concluiu-se que a altitude não influenciou no padrão de distribuição espacial das populações de palmeiras, mas afetou a composição dessa comunidade na Floresta Ombrófila Densa na Serra do Mar.

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Mites and leaf domatia: no evidence of mutualism in Coffea arabica plants. Biota Neotrop. 11(1): http://www. biotaneotropica.org.br/v11n1/en/abstract?article+bn00311012011. Abstract:We conducted experiments by blocking off pit-like domatia from old and new leaves of Coffea arabica L., using tiny resin drops, to investigate the role of domatia on i) mite abundance at the community level and on ii) leaf damages. More than 77% of the mites collected were predators, whereas 19 and 3.3% were omnivores and phytophages, respectively. Domatia blockage treatment had no influence either on mite abundances or leaf damages. However, predatory and omnivorous mites were more abundant on new than on the old leaves; phytophagous mites occurred at very low density and occupied only plants having open domatia. The absence of mutualism between mites and C. arabica probably occurred because the entrances of domatia were too small and did not enable the entry of fitoseid predators in these structures. Resumo: Domácias são pequenas estruturas presentes na junção entre as nervuras principal e secundárias das folhas de muitas espécies de plantas, que podem mediar interações mutualísticas entre ácaros e plantas. Em experimento, nós bloqueamos as domácias em formato de covas de folhas novas e velhas de Coffea arabica L. com gotas de resina, a fim de investigar o seu papel i) na abundância de ácaros na comunidade e ii) nos danos foliares. Mais de 77% dos ácaros coletados são predadores, enquanto 19 e 3,3% são onívoros e fitófagos, respectivamente. Não houve influência do bloqueio das domácias tanto na abundância quanto nos danos foliares. Entretanto, os ácaros predadores e micófagos foram mais abundantes nas folhas novas do que nas velhas; os ácaros fitófagos ocorreram em pequena densidade e ocuparam somente as plantas com domácias abertas. A ausência de mutualismo entre os ácaros e plantas de C. arabica pode ter ocorrido porque as entradas das domácias analisadas eram muito pequenas, não permitindo a entrada dos predadores fitoseídeos nessas estruturas. Palavras-chave: interações entre ácaros e plantas, comunidade de ácaros, limitação de espaço, Mata Atlântica, ruptura de mutualismo.

The effects of patch size and floral herbivory on reproductive success of Trichogoniopsis adenantha (Asteraceae) were studied in a semideciduous forest in southeastern Brazil. Plants in large patches and capitula not attacked by endophagous insects had higher seed set. The consequences of living in large or small patches for plant reproductive success are discussed.

Cyclic lipopeptides (CLPs) are non-ribosomal biosurfactants produced by Bacillus species that exhibit outstanding interfacial activity. The synthesis of CLPs is under genetic and environmental influence, and representatives from different families are generally co-produced, generating isoforms that differ in chemical structure and biological activities. This study to evaluate the effect of low and high NaCl concentrations on the composition and surface activity of CLPs produced by Bacillus strains TIM27, TIM49, TIM68, and ICA13 towards microbial enhanced oil recovery (MEOR). The strains were evaluated in mineral medium containing NaCl 2.7, 66, or 100 g L and growth, surface tension and emulsification activity were monitored. Based on the analysis of 16S rDNA, gyrB and rpoB sequences TIM27 and TIM49 were assigned to Bacillus subtilis, TIM68 to Bacillus vallismortis, and ICA13 to Bacillus amyloliquefaciens. All strains tolerated up to 100-g L NaCl, but only TIM49 and TIM68 were able to reduce surface tension at this concentration. TIM49 also showed emulsification activity at concentrations up to 66-g L NaCl. ESI-MS analysis showed that the strains produced a mixture of CLPs, which presented distinct CLP profiles at low and high NaCl concentrations. High NaCl concentration favored the synthesis of surfactins and/or fengycins that correlated with the surface activities of TIM49 and TIM68, whereas low concentration favored the synthesis of iturins. Taken together, these findings suggest that the determination of CLP signatures under the expected condition of oil reservoirs can be useful in the guidance for choosing well-suited strains to MEOR.