1,720,964 research outputs found
Intra-specific variation in the little-known Mediterranean plant Ptilostemon casabonae (L.) Greuter analysed through phytochemical and biomolecular markers
No full textPtilostemon casabonae (L.) Greuter is a Mediterranean endemism traditionally used for its health-giving properties. Little is known about this species, therefore this study provides additional information about the phytochemical and biomolecular patterns of this plant, to have a combined fingerprint as a taxonomic tool. Several P. casabonae specimens were therefore collected from three different sites, two from Sardinia (Italy) and one from Corsica and the hydroalcoholic extracts of their aerial parts were investigated through HPLC-PDA-MS/MS analysis to study the phenolic composition. Quercetin, luteolin, kaempferol, apigenin and diosmetin O-glycosides, and caffeoylquinic acid derivatives were found as main components. Samples from the three sites showed similar phenolic profiles, although statistical analyses highlighted some quantitative differences for several compounds. The biomolecular analysis included amplification and sequencing of ITS, 5S-rRNA-NTS and psbA regions. No difference was found in the nucleotides among the P. casabonae samples from different geographical origins; however, a comparison with other Ptilostemon species sequences from Genbank, revealed an interspecific variability of ITS and psbA regions.
The combination of the results of the phytochemical and biomolecular studies provide information on P. casabonae useful to depict this little-known plant, which can also be applied for future investigations and to obtain a fingerprint of it. Moreover, the stability of the phenolic profile within the species affords to identify a set of specialised metabolites useful for its chemotaxonomic characterization. At the same time, the stability of the biomolecular profile of P. casabonae, and the identification of sequences specific for this species, enables to identify useful biomolecular markers to distinguish it unequivocally
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
The fungal alternative: Insights on medicinal mushrooms-based protein-rich biomasses by submerged fermentation of agro-industrial by-products
Get PDFAmong the alternative proteins aimed at replacing those of animal origin, fungal proteins stand out as a promising resource capable of meeting environmental, health, and ethical demands. Fungal biomasses, or
mycoproteins, are indeed rich in proteins and other macro- and micronutrients, while low in fats. However, their production is an ongoing challenge. This study focused on submerged fermentation, a highly controllable process that can couple high yields and agro-industrial by-products exploitation as growth media.
Five medicinal mushrooms (Ganoderma resinaceum, Pleurotus ostreatus, Cordyceps militaris, Pleurotus eryngii, and Lentinula edodes) were tested for their biomass growth, protein content, and antioxidant properties on several agro-industrial by-product-based media. Among the experimental lines, the highest biomass production and protein content (51%) were achieved in P. eryngii grown in black solider fly (Hermetia illucens) exuviae-media.
Concerning the antioxidant properties, the production of fungal extracts through microwave-assisted maceration was as performing as, if not better than, ethanolic extraction
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Mycoprotein: a way for a more sustainable food system
No full textThe seventeen Sustainable Development Goals (SDG) are the blueprint to achieve a better and more sustainable future for all. One way to reach this goal is to look and be inspired by nature biodiversity.
Microbial biodiversity could be indeed a key factor to achieve several SDG, as environmental degradation, climate change, and sustainable food system. The transition to more sustainable food systems will require
many changes, including the search for a new source of food or feed with a lower impact of intensive agriculture and farming. Fungal biomass, known as mycoprotein, could be an alternative source of protein.
Why mycoprotein could be a sustainable novel food? First, fungal fermentation is independent of land exploitation, avoiding ethical issues by not competing with food and farm industries. Moreover, fungal
growth could be handled in an economic and energetic sustainable way, as required by the principle of the green economy. Indeed, fungal fermentation may be carried out using agro-industrial by-products (AIBPs),
valorizing them as valuable feedstocks for a new production system.
This project was aimed to investigate the production of high-value fungal biomass with low economic and environmental impact. Medicinal mushrooms were chosen because they are known to metabolize many
kinds of substrates and to produce high-value compounds. Pleurotus ostreatus, Ganoderma lucidum, Cordyceps militaris and Pleurotus eryngii were grown in different cultural conditions. Twenty-five cultural
lines were set up in submerged fermentation using different by-products including AIBPs. The first goal was to assess the effects of different AIBPs, C, and N sources and ratios on the biomass production yields: results
indicated the optimal growth medium was often strain-dependent. More in detail, the best yields were obtained in the presence of insect breeding and AIBPs, where the biomass recovery of some strains was comparable to the control (rich synthetic medium).
Once the optimal growth condition was set for each fungus, the nutritional quality of the biomass was evaluated. It should be indeed noted that great variability in the nutritional composition may be found among fungi, due to species, strains, type of substrate used, fermentation time, type of storage, and conservation process. In this project, the chemical composition of the fungal biomasses was investigated using centesimal composition analysis. Fungal biomass was extracted using different methodologies and the extracts were analyzed through spectrophotometric analysis (Folin-Ciocalteu assay, FRAP, and DPPH
assays) to assess the presence of bioactive molecules that could have a positive outcome on animal and human health.
Data confirmed the major role of culture media on the nutritional value of the produced biomass. Moreover, different strains shown different biomass quality as well. G. lucidum grown on insect breeding by-product had a very high protein content, while higher lipid content was measured in C. militaris grown on cereal molasses by-products.
Results are indeed very promising but, in the future, additional effort should be done to optimize fermentation conditions, in order to achieve good nutritional value and to set up the optimal conditions for biomass production scale-up
Mycoproteins of medicinal mushroom from submerged fermentation of agroindustrial byproducts
No full textThe global population is constantly growing and likely to exceed 10 billion by 2060[1], thus revising food production and its resources is necessary. Our planet is overexploited and 80% of Earth’s agricultural land is
used for livestock[2], for meat and meat derivates consumption, which have heavy environmental impact (high water consumption, production of greenhouse gases, use of territorial resources, deforestation and biodiversity loss). To overcome these problems without depriving human diet of proteins, several solutions have arisen over time, such as protein-rich plants, synthetic meat and insects.Mycoproteins can be a valid alternative. Fungi are highly prone to biotechnological applications, such as making plant matrices more digestible by degrading lignin for feed purpose, enriching plant wastes in fatty acids and proteins, including essential amino acids, and for using their biomasses as probiotics. Moreover, these processes are often coupled with production of
valuable metabolites such as vitamins and pigments[3]. Although retrieving proteins from fungi has already been achieved using solid state fermentation, it arouses technological and environmental concerns. Submerged fermentation is instead a more sustainable and controlled solution, avoiding seasonal process dependance.
Developing products based on this technology could be the foundation for a new ‘green’ food frontier. Five edible medicinal mushrooms (Ganoderma resinaceum, Pleurotus ostreatus, Cordyceps militaris, Pleurotus
eryngii and Lentinula edodes) preserved in the Mycotheca Universitatis Taurinensis (University of Torino) were selected. To develop economic and energetic sustainable process, growth media were based on
agroindustrial by-products (e.g. wheat vinasses, insects exuviae, tomato peels, etc.) coming from local companies, to identify the media yielding the more fungal biomass. Then, once selected the nine best performing media, the proximate compositions of the fungal biomasses were analyzed to identify the highest protein content biomass for future studies focused on fungal protein production. Among the experimental lines,
both the highest biomass production (24 g/L dw) and protein content (51% dw) were achieved in P. eryngii grown in Hermetia illucens exuviae-based media. To the authors’ knowledge, this is the first work exploiting
insect exuviae-based media to sustain fungal growth in SmF. At the same time, antioxidant activity of the extracts retrieved from these fungal biomasses was measured. Extracts were obtained via conventional 24-h
maceration or fast microwave (MW) treatment, using water or ethanol as solvents. Data indicated that MW method led to comparable antioxidant activity yields, opening new possibilities in future (poly)phenolic
extraction protocols with more feasible and sustainable techniques. Studies are ongoing using different fungi and by-products in respect of the circular Economy and sustainability principles. The present project leads to
a better understanding of sustainable fungal fermentation, sustainable downstream processes of valuable biomasses for their potential exploitation in food and feed sector
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