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On a coal specimen possibly associated with the classical Mio-Pleistocene São Jorge leaf bed site, Madeira Island, Portugal
Publication . Marques, Carlos A. Góis; Correia, Pedro; Sequeira, Miguel Menezes de; Góis-Marques, Carlos A.; Sequeira, Miguel
Due to the unusual presence of coal seams within a volcanic island, the São Jorge lignite, located in the north side
of Madeira Island, was since the early 19th century a magnet for naturalists. In 1854 the site was visited by Sir
Charles Lyell and Georg Hartung, where both discovered a leaf-bed associated with the lignite. This finding pro vided key proofs to Lyell's uniformitarian theory of the formation of volcanic islands and the long-term existence
of laurel forests in Macaronesia. Despite its historical importance, lignite specimens from São Jorge remain
unknown to date. Recently, the study of Funchal Natural History Museum (MMF, Madeira Island, Portugal)
collections revealed a coal specimen associated with the classical site of São Jorge. Here we provide a critical anal ysis of this specimen using historical and palaeobotanical approaches. We show that this coal is not a lignite from
São Jorge and that it was not collected in ca. 1905. Historically, the São Jorge site was covered by a landslide until
1917, making it inaccessible. Furthermore, the coal is either a bituminous coal or anthracite and contains typical
rhizomorph fossils of extinct Lycophytes known as Stigmaria ficoides (Sternb.) Brongn., as already indicated in the
old MMF record books. The coal is most likely a late Carboniferous (Pennsylvanian, 323.4–298.9 Ma) specimen
from the early 20th century British coaling industry on Madeira Island, imported from the UK, which, at some
point, was erroneously labelled as originating from the 7–1.8 Ma São Jorge outcrop in Madeira.
Microextraction techniques for antibiotics surveillance in the food chain and environment
Publication . Antos, Joanna; García-Cansino, Laura; Ángeles García, María; Ginter-Kramarczyk, Dobrochna; Marina, María Luisa; Zembrzuska, Joanna; Câmara, José Sousa; Pereira, Jorge A. M.; Câmara, José; Augusto Machado Pereira, Jorge
Antibiotics are commonly used to prevent and treat infections in human medicine, animal farming, and aqua culture. However, their excessive use can result in the development of antibiotic resistance and the presence of
antibiotic residues in the food and environment. Therefore, it is essential to monitor antibiotic use and assess
resistance, but the lack of standardisation and long-term quantitative data on antibiotic usage in different animal
species is very challenging. Sample preparation techniques, such as solid-phase extraction (SPE) and liquid-liquid
extraction (LLE), have been widely used, but they have limitations, including the need for large sample volumes,
organic solvents, and complex and labourious protocols. Microextraction techniques (μExT) that align with the
principles of Green Analytical Chemistry have gained attention in recent decades. Depending on the type of μExT
used and the target analytes, the amounts of solvents, reagents, and samples used can be reduced by up to ten
times or more. Often, the extraction time is also shortened by several orders of magnitude, labware requirements
are much lower, and the analytical hardware can be simplified without compromising acceptable analytical
performance. Notably, this includes the substitution of expensive LC-MS configurations with LC-UV or FLR
cheaper equipment and detection systems. Greener solvents, such as ionic liquids (IL), supramolecular solvents
(SUPRAS), and deep eutectic solvents (DES), have also been reported, further contributing to the development of
more sustainable and environmentally friendly antibiotic extraction and analytical procedures. The AGREE tool
metrics shows that substitution of conventional extraction approaches with μExT enables a greener profile for
any methodology developed to analyse antibiotics in different food and environmental samples. This article
provides a detailed overview of the advantages of using different μExT to monitor antibiotic usage in the food
industry and environment and discusses the challenges and opportunities in this field.
Gelatin-based ballistic gel formulated with phytosynthesized nanocellulose from Arundo donax for alpha-amylase enzyme inhibition activity
Publication . Jeevanandam, Jaison; Castro, Rita; Rodrigues, João; Castro, Rita; Rodrigues, João
Arundo donax, an indigenous plant in the Mediterranean region, has affected the growth of native vegetation as
an invasive plant, ultimately reducing soil quality and affecting the food chain in several areas of the world.
Thus, the present work aims to obtain cellulose from the A. donax leaf extract via organosolv fractionation and
bleaching method, followed by centrifugal fractionation to yield nanocellulose of moderately monodispersed
(0.428 PDI) 91.2 nm in size and a zeta potential of -35.5 mV of high stability in aqueous medium (water). In
addition, the resultant nanocellulose was formulated in ballistic gelatin hydrogel, and their antidiabetic effect via
alpha-amylase enzyme inhibition activity was also investigated. Systematic characterization of the hydrogel
samples (different volume ratios of gelatin and nanocellulose) revealed that the sample with 18:2 (v/v) gelatin:
nanocellulose content is thermally stable until 152 ◦C, releasing nanocellulose for three days from hydrogel until
45 ◦C. This study confirms the feasibility and potential of utilizing invasive plant species to extract nanocellulose
for medical purposes. Furthermore, the gelatin-formulated nanocellulose, with its demonstrated alpha-amylase
inhibition activity at a dosage of 80 µg/mL, holds the promise of being a potential revolutionary medical
gummy for sustained reduction of blood glucose levels.
Protein extracts from microalgae and cyanobacteria biomass. Techno-functional properties and bioactivity: a review
Publication . Nunes, Emmanuel; Odenthal, Kilian; Nunes, Nuno; Fernandes, Tomásia; Fernandes, Igor A.; Carvalho, Miguel A. A. Pinheiro de; Nunes, Nuno; Fernandes, Tomásia
Microalgae and cyanobacteria are photosynthetic and unicellular organisms that contain considerable amounts
of proteins, lipids, carbohydrates, and polyunsaturated fatty acids, among others, with applications in the
cosmetic, pharmaceutical, and food industries. These microorganisms can accumulate protein up to 70 % of total
biomass depending on the microalgal strain, hence they have been regarded as an alternative protein source for
the future. Microalgal proteins have important applications such as emulsifying, foaming, and gelation prop erties, which are important for the determination of quality and texture of foods. Some microalgal peptides
possess important bioactivity with many health-benefit effects. Therefore, to maximize the production of proteins
from microalgae and cyanobacteria, many protein extraction procedures have been studied to increase the
economic return. They have been tested towards higher protein yields at low energy cost, the preservation of
protein native properties, and lower cell debris. This later is fundamental to facilitate the subsequent purification
processes so that the overall cost can be reduced. The aim of this work is to review some cell disruption processes
for the extraction of protein from microalgae and cyanobacteria, considering that this step is crucial for the
overall process due to the high rigidness of microalgal cell covering, which can hamper the release of proteins. It
also aims at reviewing the purification techniques after cellular disruption, from conventional to more recent
approaches, and finally addresses the antioxidant, antidiabetic, antihypertensive, antibacterial and other
bioactive properties of microalgal protein hydrolysates and peptides.
Conexões interlinguísticas do léxico da cultura açucareira na globalização do mundo atlântico: Madeira, Canárias, Brasil e América Espanhola
Publication . Nunes, Naidea Nunes; Nunes Nunes, Naidea
A ilha da Madeira foi o epicentro do processo linguístico e cultural de transmissão do
conhecimento da atividade açucareira no Atlântico. A partir do século XV, a Madeira,
as Canárias, o Brasil e a América espanhola são lugares de interconexões, diálogos e trocas
linguísticas e culturais à volta do açúcar. Muitos dos termos da cultura açucareira regista dos como brasileirismos nos dicionários da língua portuguesa do Brasil e de Portugal
são, na verdade, madeirensismos disseminados nos dois lados do Atlântico. Posto isto,
pretende-se comparar alguns termos da cultura açucareira presentes nos dicionários
do Português Europeu e do Português do Brasil, nomeadamente no Vocabulario de
Bluteau (1712-1721) e no Diccionario da Lingua Portugueza de Morais Silva (1789 e 1813),
os primeiros a averbar a terminologia do açúcar no Brasil, recebida da Madeira. Confron tam-se estes com a edição de Portugal do Dicionário Houaiss da Língua Portuguesa
(2005), adaptado da edição brasileira de 2001. Segue-se a comparação com o Tesoro Léxico Canario-Americano de Corrales e Corbella (2010), uma vez que este vocabulário
foi levado da ilha da Madeira para as Canárias e a partir daí chegou à América espanhola.
Depois, mostra-se como o Dicionário da Língua Portuguesa da Academia das Ciências
de Lisboa e outros dicionários online contemporâneos não registam os regionalismos
da cultura açucareira que ainda hoje existem na ilha da Madeira e estão presentes em
vários territórios, atestando as inter-relações sócio-históricas, linguísticas e culturais
do passado. Acrescenta-se a este estudo a documentação oral contemporânea sobre
a cultura açucareira, recolhida na Madeira, nas Canárias, no Brasil, na Venezuela e na
Colômbia. A partir da comparação da documentação lexicográfica, em português e em
espanhol, conclui-se que a terminologia açucareira existente nos dois lados do Atlântico
confirma o percurso linguístico, histórico e geográfico da cana-de-açúcar, introduzida na
América latina a partir da Madeira e das Canárias.