Pigments from Antarctic bacteria and their biotechnological applications.

Pigments from microorganisms have triggered great interest in the market, mostly by their "natural" appeal, their favorable production conditions, in addition to the potential new chemical structures or naturally overproducing strains. They have been used in: food, feed, dairy, textile, pharmaceutical, and cosmetic industries. The high rate of pigment production in microorganisms recovered from Antarctica in response to selective pressures such as: high UV radiation, low temperatures, and freezing and thawing cycles makes this a unique biome which means that much of its biological heritage cannot be found elsewhere on the planet. This vast arsenal of pigmented molecules has different functions in bacteria and may exhibit different biotechnological activities, such as: extracellular sunscreens, photoprotective function, antimicrobial activity, biodegradability, etc. However, many challenges for the commercial use of these compounds have yet to be overcome, such as: the low stability of natural pigments in cosmetic formulations, the change in color when subjected to pH variations, the low yield and the high costs in their production. This review surveys the different types of natural pigments found in Antarctic bacteria, classifying them according to their chemical structure. Finally, we give an overview of the main pigments that are used commercially today.

Extracorporeal Membrane Oxygenation in COVID-19 Treatment: a Systematic Literature Review.

INTRODUCTION: The present study intends to systematically review the literature on the use of extracorporeal membrane oxygenation (ECMO) in patients with coronavirus disease 2019 (COVID-19). METHODS: The research was carried out according to the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA). Studies were selected from PubMed/MEDLINE and LILACS databases between December 2019 and May 17 2020, using the descriptors "ECMO AND COVID-19", "Extracorporeal Membrane Oxygenation AND COVID-19", "ECLS AND COVID-19", and "Extracorporeal Life Support AND COVID-19". Exclusion criteria were government epidemiological bulletins, comments, literature reviews, and articles without full access to content. RESULTS: Two hundred and thirty-three scientific productions were found, however only 18 did not met the exclusion criteria and could be included in this study, amouting to a total of 911 patients - 624 (68.5%) men, 261 (28.6%) women, and 26 (2.8%) without sex information. The mean age of the patients was 53.7 years. ECMO was necessary in 274 (30.1%) people (200 [73%] submitted to veno-venous ECMO, nine [3.3%] to veno-arterial ECMO, and seven [2.5%] moved between these two types or needed a more specific ECMO according to the disease prognosis). Five studies did not specify the type of ECMO used, amounting 57 (20.8%) patients. Five patients (1.8%) were discharged, 77 (28.1%) died, 125 (45.6%) remained hospitalized until publication time of their respective studies, and 67 patients (24.4%) had no outcome information. CONCLUSION: It is evident that more research, covering larger populations, must be carried out in order to clearly elucidate the role of ECMO in the treatment of COVID-19.