Microorganisms dominate most of Antarctic ecosystems and play a crucial role in their functioning. They are called extremophilic microorganisms with unique and versatile metabolic properties with ...possible biotechnological applications in several areas. The aim of the present study was to identify psychrotolerant microorganisms from Antarctic continent samples and to screen them for antimicrobial effects. Phylogenetic analyses revealed that most isolates were closely related to recognized species, including those recovered previously from Antarctica, which belonged to the major phyla Firmicutes, Bacteroidetes, Actinobacteria, and Proteobacteria (classes Alpha, Beta, and Gammaproteobacteria). A total of 326 bacterial isolates, distributed in 39 different genera, were recovered and identified based on sequencing of the 16S rRNA gene. The main representative genera were
Arthrobacter
,
Psychrobacter
,
Pseudoalteromonas
, and
Rhodococcus
. Antimicrobial screening revealed fifteen isolates capable of inhibiting growth of at least one of the indicator strains:
Escherichia coli
,
Micrococcus luteus
,
Staphylococcus aureus
,
Bacillus subtilis
, and
Candida albicans
. One psychrotolerant bacterium,
Pseudomonas
sp. isolate 99, showed a broad antimicrobial range, in addition to antiproliferative and antiparasitic activity. Overall, the small number of antibiotic-producing isolates obtained and the weakness of their inhibition halos corroborated previous findings suggesting that cold-loving bacteria from Antarctica are not as good as their relatives from mesophilic environments for antimicrobial prospecting. Nonetheless, antiproliferative and antiparasitic results observed are promising and suggest that there is an untapped wealth in Antarctic environments for bioprospecting compounds with pharmaceutical potential application.
Abstract
Hydrocarbons may have a natural or anthropogenic origin and serve as a source of carbon and energy for microorganisms in Antarctic soils. Herein, 16S rRNA gene and shotgun sequencing were ...employed to characterize taxonomic diversity and genetic potential for hydrocarbon degradation of the microbiome from sediments of sites located in two Antarctic islands subjected to different temperatures, geochemical compositions, and levels of presumed anthropogenic impact, named: Crater Lake/Deception Island (pristine area), Whalers Bay and Fumarole Bay/Deception Island (anthropogenic-impacted area), and Hannah Point/Livingston Island (anthropogenic-impacted area). Hydrocarbon concentrations were measured for further correlation analyses with biological data. The majority of the hydrocarbon-degrading genes were affiliated to the most abundant bacterial groups of the microbiome: Proteobacteria and Actinobacteria. KEGG annotation revealed 125 catabolic genes related to aromatic hydrocarbon (styrene, toluene, ethylbenzene, xylene, naphthalene, and polycyclic hydrocarbons) and aliphatic (alkanes and cycloalkanes) pathways. Only aliphatic hydrocarbons, in low concentrations, were detected in all areas, thus not characterizing the areas under study as anthropogenically impacted or nonimpacted. The high richness and abundance of hydrocarbon-degrading genes suggest that the genetic potential of the microbiome from Antarctic sediments for hydrocarbon degradation is driven by natural hydrocarbon occurrence.
Hydrocarbon input in Antarctic soils may result from anthropogenic and natural sources. In this case, a careful investigation was performed to evaluate Antarctic soil microorganisms’ genetic potential for hydrocarbon degradation.
The marine environment offers both economic and scientific potential which are relatively untapped from a biotechnological point of view. These environments whilst harsh are ironically fragile and ...dependent on a harmonious life form balance. Exploitation of natural resources by exhaustive wild harvesting has obvious negative environmental consequences. From a European industry perspective marine organisms are a largely underutilised resource. This is not due to lack of interest but due to a lack of choice the industry faces for cost competitive, sustainable and environmentally conscientious product alternatives. Knowledge of the biotechnological potential of marine organisms together with the development of sustainable systems for their cultivation, processing and utilisation are essential. In 2010, the European Commission recognised this need and funded a collaborative RTD/SME project under the Framework 7-Knowledge Based Bio-Economy (KBBE) Theme 2 Programme ‘Sustainable culture of marine microorganisms, algae and/or invertebrates for high value added products’. The scope of that project entitled ‘Sustainable Production of Biologically Active Molecules of Marine Based Origin’ (BAMMBO) is outlined. Although the Union is a global leader in many technologies, it faces increasing competition from traditional rivals and emerging economies alike and must therefore improve its innovation performance. For this reason innovation is placed at the heart of a European Horizon 2020 Strategy wherein the challenge is to connect economic performance to eco performance. This article provides a synopsis of the research activities of the BAMMBO project as they fit within the wider scope of sustainable environmentally conscientious marine resource exploitation for high-value biomolecules.
In the Antarctic environment, yeasts are versatile eukaryotes that have shown wide dispersion in different substrates, producing active enzymes in extreme conditions, but their relevance in ...biotechnological applications is largely unknown. The aim of this study was to evaluate the production of extracellular hydrolases by yeasts isolated from Antarctic lichens and molecularly identify these isolates. From a total of 144 isolates on the screening, 109 (76%) produced at least one of the hydrolases tested, with most activities for proteases 59 (41%), cellulases 58 (40%), esterases 57 (39%), lipases 29 (20%), amylases 23 (16%) and pectinases 20 (14%). Among these isolates, 76 were identified, most belonged to the phylum Basidiomycota (n=73) with the dominance of Vishniacozyma victoriae (n=27), Cystobasidium alpinum (n=3), Mrakia niccombsii (n=3), Cystobasidium laryngis (n=2), Bannozyma yamatoana (n=2), Holtermanniella nyarrowii (n=2), and Glaciozyma martinii (n=2). This study is the first one reporting extracellular enzyme production by yeasts isolated from thallus of the species of Antarctic lichens Lecania brialmontii, Polycauliona candelaria, Usnea capillacea, Cladonia metacorallifera, and Polycauliona regalis. With these data, it's possible to confirm lichens as a source of hydrolase-producing yeasts, reinforcing the potential of these microorganisms in bioprospecting studies of catalytic molecules from polar regions that may be useful in promising biotechnological applications.
Currently, antimicrobial resistance has become a global public health problem, which has made the need for new antimicrobial compounds to deal with resistant infections an emergency. However, ...environments that once offered so many innovative molecules, now already exhaustively exploited, do not meet this need. In this context, a geographically isolated, under-explored and extreme environment, such as Antarctica, which holds organisms with unique physiological and biochemical characteristics, assumes great importance as a potential source of new compounds with antimicrobial activity. In this patent review, we investigate the state of technological development in the field of antimicrobial compounds obtained from Antarctic organisms, highlighting the main countries and researchers active in the field, the species utilized, the compounds obtained, and their possible therapeutic applications. As results, few patent documents were found, however they encompass a wide diversity of compounds and species, indicating a great antimicrobial potential present in Antarctic biota, including compounds active against the most important human pathogenic microorganisms, such as including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp. and multi-resistant Mycobacterium tuberculosis. Furthermore, due to the increasing trend in patent applications, a significant rise in the number of patents in this area is expected in the coming years.
During initial stage of copyediting, extra columns were spanned in Table 2; i.e., 6 and 7 and 10 and 11 resulting from automation. This produced an extra space between columns, which went unnoticed ...following the proofing stage. There was no request for a correction until publication. The publisher sincerely apologizes to the authors for the inconvenience caused. The original article has been corrected.
Leishmaniasis is a disease of public health relevance that demands new therapeutic alternatives due to the toxicity of conventional treatments. In this study, 27 plants of interest to the Unified ...Health System (SUS) were evaluated for cytotoxicity in macrophages, leishmanicidal activity and production of nitric oxide (NO). None of the species demonstrated cytotoxicity to macrophages (CC50 >100 μg/mL). Extracts from Chenopodium ambrosioides, Equisetum arvense, Maytenus ilicifolia showed greater efficacy in inducing the death of Leishmania amazonensis amastigotes with IC50 of 68.4, 82.3, 75.7 μg/mL, respectively. The species Cynara scolymus, Punica granatum and Passiflora alata were the most effective in inducing an increase in the indirect concentration of NO (41.31, 29.30 and 28.86 µM, respectively) in cultures of macrophages infected with L. amazonensis. Furthermore, Punica granatum was also the most effective species in inducing an increase in NO in macrophages infected by Leishmania chagasi (19.90 µM). The results obtained so far support the continuation of studies, with the possibility of developing safer and more effective treatments for leishmaniasis, using natural products. The identification of plants that stimulate the production of NO in macrophages infected by Leishmania opens doors for more detailed investigations of the mechanism of action of these natural products.Leishmaniasis is a disease of public health relevance that demands new therapeutic alternatives due to the toxicity of conventional treatments. In this study, 27 plants of interest to the Unified Health System (SUS) were evaluated for cytotoxicity in macrophages, leishmanicidal activity and production of nitric oxide (NO). None of the species demonstrated cytotoxicity to macrophages (CC50 >100 μg/mL). Extracts from Chenopodium ambrosioides, Equisetum arvense, Maytenus ilicifolia showed greater efficacy in inducing the death of Leishmania amazonensis amastigotes with IC50 of 68.4, 82.3, 75.7 μg/mL, respectively. The species Cynara scolymus, Punica granatum and Passiflora alata were the most effective in inducing an increase in the indirect concentration of NO (41.31, 29.30 and 28.86 µM, respectively) in cultures of macrophages infected with L. amazonensis. Furthermore, Punica granatum was also the most effective species in inducing an increase in NO in macrophages infected by Leishmania chagasi (19.90 µM). The results obtained so far support the continuation of studies, with the possibility of developing safer and more effective treatments for leishmaniasis, using natural products. The identification of plants that stimulate the production of NO in macrophages infected by Leishmania opens doors for more detailed investigations of the mechanism of action of these natural products.
This study evaluated the effects of dietary macauba pulp on the growth performance, carcass, and pork traits of growing-finishing pigs; and whether differences in residual feed intake breeding values ...could influence the pigs’ growth responses to macauba pulp inclusion in the diet. A total of 282 (34.8 ± 4.40 kg) pigs (barrows and females), progeny of sires with high (HRFI) or low (LRFI) breeding value for residual feed intake, were pair-housed on the basis of sex, breeding value, and initial BW. Diets with (macauba) or without (control) of 50 g/kg of macauba pulp inclusion were randomly assigned to the experimental pens. There were eight treatment groups: HRFI barrows were fed the control diet; HRFI barrows were fed the macauba diet; LRFI barrows were fed the control diet; LRFI barrows were fed the macauba diet; HRFI female pigs were fed the control diet; HRFI female pigs were fed the macauba diet; LRFI female pigs were fed the control diet; and LRFI female pigs were fed the macauba diet. The trial lasted 90 days and was divided into four phases: growing phase 1 (G1) and 2 (G2); and finishing phases 1 (F1) and 2 (F2). There was no interaction between sex, breeding value, and diet for performance, carcass, and pork traits. Barrows had higher feed intake (ADFI), daily gain (ADG), feed conversion rate (FCR), and final body weight than female pigs. The breeding value had no effect on performance measurements. The inclusion of macauba pulp in the pigs’ diets did not affect any growth parameter during G1, G2 and F1 phases. However, reduced ADFI and improved FCR were observed in F2. Female pigs had lower backfat thickness (BF) and higher loin eye area (LEA) than barrows. HRFI pigs had higher hot carcass weight and LEA, and lower BF than LRFI pigs. There was no effect of macauba pulp inclusion on carcass traits. Pork from barrows presented lower Warner–Bratzler shear force and higher fat content than pork from the females. There was no effect of breeding value on pork traits. Pork from pigs fed the macauba diet showed lower moisture content and water-holding capacity. In conclusion, macauba pulp can partially replace corn without reducing the performance of pigs. Regardless of sex and breeding value for RFI, pigs responded similarly to macauba pulp inclusion in diets.
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