36 research outputs found
Molecular, morphological and chemical diversity of two new species of Antarctic Diatoms, Craspedostauros ineffabilis sp. nov. and Craspedostauros zucchellii sp. nov.
The current study focuses on the biological diversity of two strains of Antarctic diatoms
(strains IMA082A and IMA088A) collected and isolated from the Ross Sea (Antarctica) during the
XXXIV Italian Antarctic Expedition. Both species presented the typical morphological characters of
the genus Craspedostauros: cribrate areolae, two “fore-and-aft” chloroplasts and a narrow “stauros”.
This classification is congruent with the molecular phylogeny based on the concatenated 18S rDNArbcL-psbC alignment, which showed that these algae formed a monophyletic lineage including six
taxonomically accepted species of Craspedostauros. Since the study of the evolution of this genus and
of others raphe-bearing diatoms with a “stauros” is particularly challenging and their phylogeny
is still debated, we tested alternative tree topologies to evaluate the relationships among these taxa.
The metabolic fingerprinting approach was implemented for the assessment of the chemical diversity
of IMA082A and IMA088A. In conclusion, combining (1) traditional morphological features used
in diatoms identification, (2) phylogenetic analyses of the small subunit rDNA (18S rDNA), rbcL
and psbC genes, and (3) metabolic fingerprint, we described the strains IMA082A and IMA088A as
Craspedostauros ineffabilis sp. nov. and Craspedostauros zucchellii sp. nov. as new species, respectivelyinfo:eu-repo/semantics/publishedVersio
New insights into the phytochemical profile and biological properties of Lycium intricatum Bois. (Solanaceae)
This work aimed to boost the valorisation of Lycium intricatum Boiss. L. as a source of high
added value bioproducts. For that purpose, leaves and root ethanol extracts and fractions (chloroform,
ethyl acetate, n-butanol, and water) were prepared and evaluated for radical scavenging activity
(RSA) on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,20
-azino-bis (3-ethylbenzothiazoline-6-sulfonic
acid) (ABTS) radicals, ferric reducing antioxidant power (FRAP), and metal chelating potential against
copper and iron ions. Extracts were also appraised for in vitro inhibition of enzymes implicated on the
onset of neurological diseases (acetylcholinesterase: AChE and butyrylcholinesterase: BuChE), type-2
diabetes mellitus (T2DM, α-glucosidase), obesity/acne (lipase), and skin hyperpigmentation/food
oxidation (tyrosinase). The total content of phenolics (TPC), flavonoids (TFC), and hydrolysable
tannins (THTC) was evaluated by colorimetric methods, while the phenolic profile was determined
by high-performance liquid chromatography, coupled to a diode-array ultraviolet detector (HPLCUV-DAD). Extracts had significant RSA and FRAP, and moderate copper chelation, but no iron
chelating capacity. Samples had a higher activity towards α-glucosidase and tyrosinase, especially
those from roots, a low capacity to inhibit AChE, and no activity towards BuChE and lipase. The
ethyl acetate fraction of roots had the highest TPC and THTC, whereas the ethyl acetate fraction
of leaves had the highest flavonoid levels. Gallic, gentisic, ferulic, and trans-cinnamic acids were
identified in both organs. The results suggest that L. intricatum is a promising source of bioactive
compounds with food, pharmaceutical, and biomedical applications.info:eu-repo/semantics/publishedVersio
Total phenolic levels, in vitro antioxidant properties, and fatty acid profile of two microalgae, tetraselmis marina strain IMA043 and naviculoid diatom strain IMA053, isolated from the North Adriatic Sea
This work studied the potential biotechnological applications of a naviculoid diatom (IMA053) and a green microalga (Tetraselmis marina IMA043) isolated from the North Adriatic Sea. Water, methanol, and dichloromethane (DCM) extracts were prepared from microalgae biomass and evaluated for total phenolic content (TPC) and in vitro antioxidant properties. Biomass was profiled for fatty acid methyl esters (FAME) composition. The DCM extracts had the highest levels of total phenolics, with values of 40.58 and 86.14 mg GAE/g dry weight (DW in IMA053 and IMA043, respectively). The DCM extracts had a higher radical scavenging activity (RSA) than the water and methanol ones, especially those from IMA043, with RSAs of 99.65% toward 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt (ABTS) at 10 mg/mL, and of 103.43% against 2,2-diphenyl-1-picrylhydrazyl (DPPH) at 5 mg/mL. The DCM extract of IMA053 displayed relevant copper chelating properties (67.48% at 10 mg/mL), while the highest iron chelating activity was observed in the water extract of the same species (92.05% at 10 mg/mL). Both strains presented a high proportion of saturated (SFA) and monounsaturated (MUFA) fatty acids. The results suggested that these microalgae could be further explored as sources of natural antioxidants for the pharmaceutical and food industry and as feedstock for biofuel production.info:eu-repo/semantics/publishedVersio
Bioactive extracts from Salicornia ramosissima J. woods biorefinery as a source of ingredients for high-value industries
Salt-tolerant plants, also known as halophytes, could provide a novel source of feedstock
for biorefineries. After harvesting fresh shoots for food, the lignified fraction of Salicornia ramosissima
J. Woods could be used to produce bioactive botanical extracts for high-value industries such as
nutraceuticals, cosmetics, and biopharmaceuticals. The residual fraction after extraction can be further
used for bioenergy or lignocellulose-derived platform chemicals. This work analysed S. ramosissima
from different sources and growth stages. After pre-processing and extractions, the obtained fractions
were analysed for their contents of fatty acids, pigments, and total phenolics. Extracts were also
evaluated for their in vitro antioxidant properties and inhibitory effect towards enzymes related to
diabetes, hyperpigmentation, obesity, and neurogenerative diseases. The ethanol extract from the fibre
residue and the water extract from completely lignified plants showed the highest concentration of
phenolic compounds along with the highest antioxidant potential and enzyme-inhibitory properties.
Hence, they should be further explored in the context of biorefinery.Fundo Azul (FA-05-2017-028)info:eu-repo/semantics/publishedVersio
Controllo termografico sullo stato di adesione di materiali compositi fibrorinforzati in carbonio applicati su elementi di calcestruzzo
Development and Validation of a New Tool to Improve the Accuracy of the Hospital Mass-Casualty Incident Response Plan Activation: The PEMAAF Score
Introduction: Effective response to a mass-casualty incident (MCI) entails the activation of hospital MCI plans. Unfortunately, there are no tools available in the literature to support hospital responders in predicting the proper level of MCI plan activation. This manuscript describes the scientific-based approach used to develop, test, and validate the PEMAAF score (Proximity, Event, Multitude, Overcrowding, Temporary Ward Reduction Capacity, Time Shift Slot [Prossimita, Evento, Moltitudine, Affollamento, Accorpamento, Fascia Oraria], a tool able to predict the required level of hospital MCI plan activation and to facilitate a coordinated activation of a multi-hospital network.Methods: Three study phases were performed within the Metropolitan City of Milan, Italy: (1) retrospective analysis of past MCI after action reports (AARs); (2) PEMAAF score development; and (3) PEMAAF score validation. The validation phase entailed a multi-step process including two retrospective analyses of past MCIs using the score, a focus group discussion (FGD), and a prospective simulation-based study. Sensitivity and specificity of the score were analyzed using a regression model, Spearman's Rho test, and receiver operating characteristic/ROC analysis curves.Results: Results of the retrospective analysis and FGD were used to refine the PEMAAF score, which included six items-Proximity, Event, Multitude, Emergency Department (ED) Overcrowding, Temporary Ward Reduction Capacity, and Time Shift Slot-allowing for the identification of three priority levels (score of 5-6: green alert; score of 7-9: yellow alert; and score of 10-12: red alert). When prospectively analyzed, the PEMAAF score determined most frequent hospital MCI plan activation (>10) during night and holiday shifts, with a score of 11 being associated with a higher sensitivity system and a score of 12 with higher specificity.Conclusions: The PEMAAF score allowed for a balanced and adequately distributed response in case of MCI, prompting hospital MCI plan activation according to real needs, taking into consideration the whole hospital response network
Multi-gene phylogeny reveals a new genus and species of Hapalidiales (Rhodophyta) from Antarctica: Thalassolithon adeliense gen. & sp. nov.
Non-geniculate coralline algal specimens were collected in 2013 during the XXVIII Italian Expedition to Antarctica in Adélie Cove (Terra Nova Bay; Ross Sea) and deposited in the collections of the Italian National Antarctic Museum (MNAIT, Section of Genoa). Specimens were characterized through a polyphasic approach combining DNA sequence data obtained for four genes (psbA, rbcL, 18S rDNA and cox1) with morpho-anatomical observations. DNA sequences revealed that all specimens belonged to the same species. Phylogenetic reconstructions unambiguously recovered this alga as a member of the order Hapalidiales, but without any close relationship to a genus of this order currently recognized on a molecular phylogenetic basis. Instead, it formed a well-supported lineage with specimens named ‘Hapalidiales sp. ZH-Twist-2019’, collected in New Zealand, for which no formal assignment at genus level has been proposed. Species delimitation methods (ABGD, PTP, GMYC) applied to the psbA dataset indicated that the Adélie Cove coralline alga is a distinct species from all other known hapalidialean species for which such sequences are available. A new genus, Thalassolithon gen. nov., is proposed for T. adeliense sp. nov
Microglena antarctica sp. nov. a New Antarctic Green Alga from Inexpressible Island (Terra Nova Bay, Ross Sea) Revealed through an Integrative Approach
One of the aims of the XXXIV Italian Antarctic Expedition is the study of the photosynthetic biodiversity of the Ross Sea. To achieve this goal, sea-ice samples were collected from Inexpressible Island and a strain of a green microalga (IMA076A) was isolated for morphological and molecular investigations. Combining: (1) phylogenetic analyses of the small subunit rDNA (18S rDNA) and of the internal transcribed spacer 2 (ITS-2) sequences; (2) species delimitation methods; (3) comparative analyses of the secondary structures of ITS-2 and compensatory base changes; (4) morphological, ultrastructural and ecological features, we described the strain IMA076A and its relatives as the new species Microglena antarctica sp. nov. The discovery of a new species of Chlorophyceae highlights that the biological diversity of Antarctic microalgae is more extensive than previously thought and that molecular phylogeny together with compensatory base changes (CBCs) approach are pivotal in the identification of cryptic microalgae
<i>Microglena antarctica</i> sp. nov. a New Antarctic Green Alga from Inexpressible Island (Terra Nova Bay, Ross Sea) Revealed through an Integrative Approach
One of the aims of the XXXIV Italian Antarctic Expedition is the study of the photosynthetic biodiversity of the Ross Sea. To achieve this goal, sea-ice samples were collected from Inexpressible Island and a strain of a green microalga (IMA076A) was isolated for morphological and molecular investigations. Combining: (1) phylogenetic analyses of the small subunit rDNA (18S rDNA) and of the internal transcribed spacer 2 (ITS-2) sequences; (2) species delimitation methods; (3) comparative analyses of the secondary structures of ITS-2 and compensatory base changes; (4) morphological, ultrastructural and ecological features, we described the strain IMA076A and its relatives as the new species Microglena antarctica sp. nov. The discovery of a new species of Chlorophyceae highlights that the biological diversity of Antarctic microalgae is more extensive than previously thought and that molecular phylogeny together with compensatory base changes (CBCs) approach are pivotal in the identification of cryptic microalgae