Extração de 6-gingerol do gengibre utilizando solventes eutécticos profundos

Mestrado em Biotecnologia Industrial e AmbientalO gengibre é uma planta que tem atraído um interesse crescente tanto no sector alimentar como farmacêutico devido às suas propriedades medicinais. Como planta medicinal, é uma das mais antigas e populares do mundo. As suas propriedades terapêuticas advêm dos compostos bioativos presentes na sua composição, entre os mais importantes destacam-se os compostos fenólicos, nomeadamente o 6-shogaol e o 6-gingerol. Estes compostos despertam um grande interesse na comunidade científica devido ao seu poder antioxidante e anti-tumoral. Os processos convencionais de extração destes compostos requerem o uso de solventes orgânicos, no entanto, nos últimos anos tem-se intensificado a procura por solventes alternativos com maior capacidade de solvatação, eficientes e economicamente viáveis. Os solventes eutécticos profundos (DES) são uma classe de solventes novos, de baixo custo e de origem natural, baseados em percursores renováveis que apresentam baixa toxicidade, podendo ser catalogados como solventes amigos do ambiente. Neste contexto, o objetivo principal deste trabalho foca-se na obtenção de um extrato rico em compostos bioativos (nomeadamente 6-gingerol) a partir do gengibre utilizando DES como solventes de extração com possibilidade de recuperação do extrato e reciclagem dos DES, criando assim um processo sustentável. Para atingir este objetivo, foram estudadas as solubilidades de dois compostos fenólicos modelo, nomeadamente os ácidos siríngico e ferúlico em DES (puros e em solução aquosa), por forma a avaliar os DES mais promissores na solubilização dos compostos bioativos, assim como, as condições de extração. Entre as várias combinações entre doadores (ácidos orgânicos, polióis, açúcares e ureia) e aceitadores (ureia, cloreto de colina, betaína e prolina) de pontes de hidrogénio, o DES ácido propiónico:ureia foi o que apresentou melhores resultados. Com base nestes resultados e recorrendo a metodologias de superfície de resposta, foram avaliados e otimizados diversos parâmetros de extração do 6-gingerol usando soluções aquosas de DES. Simultaneamente, efetuaram-se extrações convencionais como controlo, seguido da identificação e quantificação do 6-gingerol presente nos extratos usando a cromatografia líquida de alta resolução (HPLC). A metodologia de extração do 6-gingerol a partir do gengibre usando os DES como solventes alternativos demonstrou ser mais seletiva, capaz de extrair mais 60 % de 6-gingerol quando comparado com os métodos de extração convencionais. Além disso, foi possível recuperar um extrato sólido rico a partir da solução de DES utilizando uma extração em fase sólida (SPE). Por fim, a caracterização dos extratos foi complementada com a análise da atividade antioxidante, usando o radical 2,2-difenil-1-picrilhidrazilo (DPPH). Os resultados indicam que os extratos obtidos a partir da metodologia proposta neste trabalho apresenta maior atividade antioxidante que os extratos obtidos com métodos de extração convencionais.Ginger is a plant that has attracted the attention from both the food and pharmaceutical sectors due to its medicinal properties. As a medicinal plant, it is one of the oldest and most popular in the world. Its therapeutic properties arise from the bioactive compounds it contains, among which stand the phenolic compounds, and in particular 6-shogaol and 6- gingerol. These compounds aroused great interest in the scientific community due to its antioxidant and antitumoral properties. The conventional extraction methods of these compounds require the use of organic solvents, however, in recent years, there has been an intensified search for alternative solvents with higher solvation capacity, efficient and cheap. Deep-eutectic solvents (DES) are a new class of solvents, of low cost and natural origin, based on renewable precursors that have a low toxicity and can be categorized as environmentally friendly solvents. The goal of this work focuses on obtaining an extract rich in bioactive compounds (namely 6-gingerol) from ginger using DES as extraction solvents, and to evaluate the possibility of recycling of DES, thus creating a sustainable process. For that purpose the solubility of two phenolic model compounds, namely syringic and ferulic acids, were studied in DES (neat and in aqueous solution) in order to identify the most promising DES for the bioactive compound solubilisation, as well as the best extraction conditions. Between the several combinations amongst hydrogen bond donors (organic acids, polyols, sugars and urea) and hydrogen bond acceptors (urea, choline chloride, betaine and proline), propionic acid:urea revealed to have the best results. Based on these results and using the surface response methodology, several extraction parameters of ginger extraction using aqueous solutions of DES were optimized. Simultaneously, conventional extraction assays were carried for comparison, followed by the identification and quantification of 6- gingerol present in extracts by high pressure liquid chromatography (HPLC). Once optimized the different parameters of extraction it was possible to achieve an efficient methodology capable to enhance the 6- gingerol extraction in 60% when compared with the conventional extraction methodology. Besides, an extract was successfully recovered from the DES extract solution using solid-phase extraction (SPE). The extract characterization was complemented with the analysis of the antioxidant activity using 2,2-diphenyl-1-picrylhydrazil (DPPH). Results show that the extracts obtained with the methodology proposed in this work present a higher antioxidant activity than those obtained with conventional extraction techniques

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Aspects of sexual precocity and morphometry of uterus, placenta and embryos/fetuses in Piau breed and Commercial line gilts

In view of the importance of the genetic material of local breeds in the swine industry and the lack of information about reproductive performance of Piau females, two experiments were conducted to evaluate puberty and sexual maturity as well as the morphometry of embryos/fetuses, placenta and uterus during the first 90 days of gestation in Piau breed and Commercial line gilts. In experiment I, 37 Piau and 25 commercial line gilts were used. From the 120 days of age, detection of estrus was performed using mature boars from the first to third estrus of each gilt. Data regarding to age, body weight and estrus duration were recorded. After third estrus, females were slaughtered and ovaries were collected to determine ovulation rate. In experiment II, 36 Piau and 18 commercial line gilts were distributed into three groups according to the mating: Commercial, commercial line females x commercial line male; cross-mated, Piau females x commercial line male; and Piau, Piau females x Piau male. Gilts were slaughtered at 7, 15, 30, 45, 60 and 90 days of pregnancy. Piau females reached puberty and sexual maturity at the same age as commercial line females, but with lower weight; moreover, Piau group showed negative correlations of birth weight with puberty (−0.27) and sexual maturity (−0.29). Commercial gilts presented higher ovulation rate, weight and length of uterus, and length and thoracic circumference of fetuses. Nevertheless, number of fetuses was similar in all groups at 90 days of gestation suggesting that Piau females present higher survival rates of the conceptuses. The results showed differences between the genetic groups related to fetal and placental development, gestational losses, number of ovulations and uterine development. In addition, an intermediate status of fetal weight was observed in Piau/Commercial line crossbred conceptuses; thus, the selection of Piau females on reproductive traits to be mated with commercial line males would be an alternative to contribute to improvement of intramuscular fat content

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data