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The red algal genusHypnea(Gigartinales) has a wide geographical distribution along tropical and subtropical coasts around the world. The relatively simple and plastic morphology, often influenced by the conditions of its habitat, complicates the identification ofHypneaspecies. Therefore, the number and status of some species remain in doubt. Molecular studies have been performed to supplement traditional studies based on morphology, mainly forHypneaspecies occurring in Asia. In the present study, sequence data from the DNA barcode COI-5P for 114 samples from the southeastern coast of Brazil, indicated the occurrence of six taxa. Additionally, sequence data from the UPA andrbcL markers for representatives of each of those taxa confirmed the existence of six different species. After morphological analysis and comparison with sequences available in GenBank, these species were named as follows:H. aspera, H. cervicornis, H.cf.musciformis, H. spinella, and two new species,H. flavaNauer, Cassano & M.C. Oliveira andH. edenianaNauer, Cassano & M.C. Oliveira.Hypnea cervicornis, often considered as a later synonym ofH. spinella, should be considered as a distinct species based on morphology and divergence of the three molecular markers used.Hypnea asperais a new record for the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

A screening was performed using nine marine-derived fungi as biocatalysts and the natural products (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) in order to select the microorganisms able to catalyze the biooxidation of these compounds. It was observed that only the Aspergillus sydowii CBMAI 934, Botryosphaeria sp., Eutypella sp., and Xylaria sp. presented active oxidoreductases and catalyzed the regioselective hydroxylation in the natural products. The hydroxylated metabolites obtained were 1β-hydroxy-ambrox (1a) (14%, A. sydowii CBMAI 934); 3β-hydroxy-ambrox (1b) (17%, Botryosphaeria sp.; 11%, Eutypella sp.); 3β-hydroxy-sclareol (2a) (31%, Xylaria sp.; 69%, Botryosphaeria sp.; 55%, Eutypella sp.); 18-hydroxy-sclareol (2b) (10%, Xylaria sp.); and 3β-hydroxy-sclareolide (3a) (34%, Botryosphaeria sp.; 7%, Eutypella sp.). This is the first report of biohydroxylation of (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) by whole mycelia of marine-derived fungi.

Organic carbon records in Antarctic snow are sparse despite the fact that it is of great significance to global carbon dynamics, snow photochemistry, and air-snow exchange processes. Here, surface snow total organic carbon (TOC) along with sea-salt Na(+), dust, and microbial load of two geographically distinct traverses in East Antarctica are presented, viz. Princess Elizabeth Land (PEL, coast to 180 km inland, Indian Ocean sector) and Dronning Maud Land (DML, ∼110-300 km inland, Atlantic Ocean sector). TOC ranged from 88 ± 4 to 928 ± 21 μg L(-1) in PEL and 13 ± 1 to 345 ± 6 μg L(-1) in DML. TOC exhibited considerable spatial variation with significantly higher values in the coastal samples (p < 0.001), but regional variation was insignificant within the two transects beyond 100 km (p > 0.1). Both distance from the sea and elevation influenced TOC concentrations. TOC also showed a strong positive correlation with sea-salt Na(+) (p < 0.001). In addition to marine contribution, in situ microorganisms accounted for 365 and 320 ng carbon L(-1) in PEL and DML, respectively. Correlation with dust suggests that crustal contribution of organic carbon was marginal. Though TOC was predominantly influenced by marine sources associated with sea-spray aerosols, local microbial contributions were significant in distant locations having minimal sea-spray input.