This study aimed to test different protocols for the extraction of microbial DNA from the coral Mussismilia harttii. Four different commercial kits were tested, three of them based on methods for DNA extraction from soil (FastDNA SPIN Kit for soil, MP Bio, PowerSoil DNA Isolation Kit, MoBio, and ZR Soil Microbe DNA Kit, Zymo Research) and one kit for DNA extraction from plants (UltraClean Plant DNA Isolation Kit, MoBio). Five polyps of the same colony of M. harttii were macerated and aliquots were submitted to DNA extraction by the different kits. After extraction, the DNA was quantified and PCR-DGGE was used to study the molecular fingerprint of Bacteria and Eukarya. Among the four kits tested, the ZR Soil Microbe DNA Kit was the most efficient with respect to the amount of DNA extracted, yielding about three times more DNA than the other kits. Also, we observed a higher number and intensities of DGGE bands for both Bacteria and Eukarya with the same kit. Considering these results, we suggested that the ZR Soil Microbe DNA Kit is the best adapted for the study of the microbial communities of corals.

The bioremediation of Antarctic soils is a challenge due to the harsh conditions found in this environment. To characterize better the effect of total petroleum hydrocarbon (TPH) concentrations on bacterial, archaeal and microeukaryotic communities in low (LC) and high (HC) hydrocarboncontaminated soil samples from the Maritime Antarctic clone libraries (small-subunit rRNA genes) were constructed. The results showed that a high concentration of hydrocarbons resulted in a decrease in bacterial and eukaryotic diversity; however, no effect of the TPH concentration was observed for the archaeal community. The HC soil samples demonstrated a high relative abundance of bacterial operational taxonomic units (OTUs) affiliated with unclassified group TM7 and eukaryotic OTUs affiliated with unclassified fungi from Pezizomycotina subphyla. Chemical analyses of the LC and HC soil samples revealed the presence of negligible amounts of nitrogen, thereby justifying the use of biostimulation to remediate these Antarctic soils. Microcosm experiments showed that the application of fertilizers led to an increase of up to 27.8% in the TPH degradation values. The data presented here constitute the first step towards developing the best method to deploy bioremediation in Antarctic soils and provide information to indicate an appropriate action plan for immediate use in the case of new accidents.

With the increase in human activities in cold environments, the risk of an oil spill has become higher due to the necessity of using oils to generate energy. Several accidents have occurred in the Arctic and Antarctic involving severely contaminated areas and chronic levels of contamination. In the Antarctic, the main occupations are permanent scientific and military stations, most of which are active throughout the year. Several studies evaluating the potential for biodegradation were performed using Antarctic soils, and the results were promising; however, there are no studies on the bioremediation process in soils from the core of the continent, only from the shore regions. The Antarctic continent contains a diverse microbial community that can degrade oils even under extreme conditions. In this regard, bioremediation treatments are indicated to promote a sustainable, low-cost and efficient recovery process that must be performed as soon as possible after the spill to improve this efficiency. This paper provides an unprecedented review of the bioremediation process exclusive to Antarctic soils; provides the necessary knowledge for consolidating the bioremediation process in the Antarctic environment; and suggests strategies for applying these techniques.

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The Antarctic soil microbial community has a crucial role in the growth and stabilization of higher organisms, such as vascular plants. Analysis of the soil microbiota composition in that extreme environmental condition is crucial to understand the ecological importance and biotechnological potential. We evaluated the efficiency of isolation and abundance of strict anaerobes in the vascular plant Deschampsia antarctica rhizosphere collected in the Antarctic's Admiralty Bay and associated biodiversity to metabolic perspective and enzymatic activity. Using anaerobic cultivation methods, we identified and isolated a range of microbial taxa whose abundance was associated with Plant Growth-Promoting Bacteria (PGPB) and presences were exclusively endemic to the Antarctic continent. Firmicutes was the most abundant phylum (73 %), with the genus Clostridium found as the most isolated taxa. Here, we describe two soil treatments (oxygen gradient and heat shock) and 27 physicochemical culture conditions were able to increase the diversity of anaerobic bacteria isolates. Heat shock treatment allowed to isolate a high percentage of new species (63.63 %), as well as isolation of species with high enzymatic activity (80.77 %), which would have potential industry application. Our findings contribute to the understanding of the role of anaerobic microbes regarding ecology, evolutionary, and biotechnological features essential to the Antarctic ecosystem.