Recent highlights in sustainable bio-based edible films and coatings for fruit and vegetable applications

The present review paper focuses on recent developments in edible films and coatings made of base compounds from biological sources, namely plants, animals, algae, and microorganisms. These sources include by-products, residues, and wastes from agro-food industries and sea products that contribute to sustainability concerns. Chitosan, derived from animal biological sources, such as crustacean exoskeletons, has been the most studied base compound over the past three years. Polysaccharides typically constitute no more than 3–5% of the film/coating base solution, with some exceptions, like Arabic gum. Proteins and lipids may be present in higher concentrations, such as zein and beeswax. This review also discusses the enrichment of these bio-based films and coatings with various functional and/or bioactive compounds to confer or enhance their functionalities, such as antimicrobial, antioxidant, and anti-enzymatic properties, as well as physical properties. Whenever possible, a comparative analysis among different formulations was performed. The results of the applications of these edible films and coatings to fruit and vegetable products are also described, including shelf life extension, inhibition of microbial growth, and prevention of oxidation. This review also explores novel types of packaging, such as active and intelligent packaging. The potential health benefits of edible films and coatings, as well as the biodegradability of films, are also discussed. Finally, this review addresses recent innovations in the edible films and coatings industry, including the use of nanotechnologies, aerogels, and probiotics, and provides future perspectives and the challenges that the sector is facing.info:eu-repo/semantics/publishedVersio

Antibacterial and antioxidant potential of aqueous extracts of bio-residues from agrocybe cylindracea and pleurotus ostreatus mycelium

The production of fresh mushrooms results in a large quantity of bio-residues, which may account for more than 20% of a crop volume and contributes to production costs and environmental impact, if not used. These products consist mainly of stalks, mushrooms of irregular dimensions and shape and basal material. Thus, the main objective of MicoBioExtract project is the valorisation of these bio-residues and the development of add-value by-products with bioactive compounds such as polysaccharides and phenolic compounds produced by mushrooms. In the present work, the aqueous extracts from Agrocybe cylindracea byproducts (ACB) and Pleurotus ostreatus mycelium (POM) were evaluated for potential antioxidant and antimicrobial activities. Water soluble substances were extracted from mushrooms according to two different methods. In method 1 it was performed a hot extraction (extract 1A; 90 °C; 1 h; 500 rpms). In method 2, the biomass was submitted to an extraction at room temperature (extract 2B) and the resulting residue was extracted with hot water (extract 2C; 90 °C; 1 h; 500 rpms). The aqueous extracts from POM were obtained only by method 1. Extracts were lyophilized and their bioactivity evaluated measuring the antioxidant (ABTS, DPPH and ORAC) and antimicrobial (determination of the minimum inhibitory concentration – MIC) activities. The mutagenicity was also tested (Ames assay with and without S9). Moreover, it was determined the total phenolics content of the extracts and α and β – glucans (Folin Ciocalteu and Beta-Glucan Assay methods, respectively). The results obtained from antioxidant methods showed that all extracts from both mushrooms are a potential source of natural antioxidant and phenolic compounds. According to ABTS, extract 2B from ACB showed the best value with 8.48±0.33 mg ascorbic acid equivalent (AAE)/g dry extract and 4.14±0.52 mg AAE/g dry extract for POM. Regarding the antimicrobial activity, MIC results showed that ACB and POM extracts inhibited the growth of Gram- (Salmonella enteritidis) and Gram+ (Bacillus cereus and Listeria monocytogenes). Concerning the mutagenicity, the results showed no toxic effect except for extract 1A from ACB. Regarding the β-glucan content, the extracts from ACB presented higher content of β-glucan than the C extracts from POM. Thus, aqueous extracts from mushroom bio-residues showed potential antioxidant and antimicrobial properties and to develop a circular bioeconomy approach.info:eu-repo/semantics/publishedVersio

Deuterated Ammonia in Galactic Protostellar Cores

We report on a survey of \nh2d towards protostellar cores in low-mass star formation and quiescent regions in the Galaxy. Twenty-three out of thirty-two observed sources have significant (\gsim 5\sigma) \nh2d emission. Ion-molecule chemistry, which preferentially enhances deuterium in molecules above its cosmological value of \scnot{1.6}{-5} sufficiently explains these abundances. NH2D/NH3 ratios towards Class 0 sources yields information about the ``fossil remnants'' from the era prior to the onset of core collapse and star formation. We compare our observations with predictions of gas-phase chemical networks.Comment: 16 Pages, 7 Figures, Accepted to Ap.J., to appear in the June 20, 2001 editio

The health-promoting potential of Salix spp. bark: from the phenolic composition to the in vitro bioactivity

info:eu-repo/semantics/publishedVersio

Anisotropic Radial Layout for Visualizing Centrality and Structure in Graphs

This paper presents a novel method for layout of undirected graphs, where nodes (vertices) are constrained to lie on a set of nested, simple, closed curves. Such a layout is useful to simultaneously display the structural centrality and vertex distance information for graphs in many domains, including social networks. Closed curves are a more general constraint than the previously proposed circles, and afford our method more flexibility to preserve vertex relationships compared to existing radial layout methods. The proposed approach modifies the multidimensional scaling (MDS) stress to include the estimation of a vertex depth or centrality field as well as a term that penalizes discord between structural centrality of vertices and their alignment with this carefully estimated field. We also propose a visualization strategy for the proposed layout and demonstrate its effectiveness using three social network datasets.Comment: Appears in the Proceedings of the 25th International Symposium on Graph Drawing and Network Visualization (GD 2017

Silicates in D-type symbiotic stars: an ISO overview

We investigate the IR spectral features of a sample of D-type symbiotic stars. Analyzing unexploited ISO-SWS data, deriving the basic observational parameters of dust bands and comparing them with respect to those observed in other astronomical sources, we try to highlight the effect of environment on grain chemistry and physic. We find strong amorphous silicate emission bands at 10 micron and 18 micron in a large fraction of the sample. The analysis of the 10 micron band, along with a direct comparison with several astronomical sources, reveals that silicate dust in symbiotic stars shows features between the characteristic circumstellar environments and the interstellar medium. This indicates an increasing reprocessing of grains in relation to specific symbiotic behavior of the objects. A correlation between the central wavelength of the 10 and 18 micron dust bands is found. By the modeling of IR spectral lines we investigate also dust grains conditions within the shocked nebulae. Both the unusual depletion values and the high sputtering efficiency might be explained by the formation of SiO moleculae, which are known to be a very reliable shock tracer. We conclude that the signature of dust chemical disturbance due to symbiotic activity should be looked for in the outer, circumbinary, expanding shells where the environmental conditions for grain processing might be achieved. Symbiotic stars are thus attractive targets for new mid-infrared and mm observations.Comment: 24 pages, 6 figures, 5 tables - to be published in A

Fashion, Cooperation, and Social Interactions

Fashion plays such a crucial rule in the evolution of culture and society that it is regarded as a second nature to the human being. Also, its impact on economy is quite nontrivial. On what is fashionable, interestingly, there are two viewpoints that are both extremely widespread but almost opposite: conformists think that what is popular is fashionable, while rebels believe that being different is the essence. Fashion color is fashionable in the first sense, and Lady Gaga in the second. We investigate a model where the population consists of the afore-mentioned two groups of people that are located on social networks (a spatial cellular automata network and small-world networks). This model captures two fundamental kinds of social interactions (coordination and anti-coordination) simultaneously, and also has its own interest to game theory: it is a hybrid model of pure competition and pure cooperation. This is true because when a conformist meets a rebel, they play the zero sum matching pennies game, which is pure competition. When two conformists (rebels) meet, they play the (anti-) coordination game, which is pure cooperation. Simulation shows that simple social interactions greatly promote cooperation: in most cases people can reach an extraordinarily high level of cooperation, through a selfish, myopic, naive, and local interacting dynamic (the best response dynamic). We find that degree of synchronization also plays a critical role, but mostly on the negative side. Four indices, namely cooperation degree, average satisfaction degree, equilibrium ratio and complete ratio, are defined and applied to measure people's cooperation levels from various angles. Phase transition, as well as emergence of many interesting geographic patterns in the cellular automata network, is also observed.Comment: 21 pages, 12 figure

HIFI observations of warm gas in DR21: Shock versus radiative heating

The molecular gas in the DR21 massive star formation region is known to be affected by the strong UV field from the central star cluster and by a fast outflow creating a bright shock. The relative contribution of both heating mechanisms is the matter of a long debate. By better sampling the excitation ladder of various tracers we provide a quantitative distinction between the different heating mechanisms. HIFI observations of mid-J transitions of CO and HCO+ isotopes allow us to bridge the gap in excitation energies between observations from the ground, characterizing the cooler gas, and existing ISO LWS spectra, constraining the properties of the hot gas. Comparing the detailed line profiles allows to identify the physical structure of the different components. In spite of the known shock-excitation of H2 and the clearly visible strong outflow, we find that the emission of all lines up to > 2 THz can be explained by purely radiative heating of the material. However, the new Herschel/HIFI observations reveal two types of excitation conditions. We find hot and dense clumps close to the central cluster, probably dynamically affected by the outflow, and a more widespread distribution of cooler, but nevertheless dense, molecular clumps.Comment: Accepted for publication by A&