86 research outputs found
Relation Structure molĂ©culaire - Odeur Utilisation des RĂ©seaux de Neurones pour lâestimation de lâOdeur Balsamique
Les molĂ©cules odorantes (parfums ou flaveurs) sont utilisĂ©es dans une grande variĂ©tĂ© de produits de consommation, pour inciter les consommateurs Ă associer les impressions favorables Ă un produit donnĂ©. La Relation Structure molĂ©culaire-Odeur (SOR) est cruciale pour la synthĂšse de ces molĂ©cules mais est trĂšs difficile Ă Ă©tablir due Ă la subjectivitĂ© de lâodeur. Ce travail prĂ©sente une approche de prĂ©diction de l'odeur des molĂ©cules basĂ©e sur les descripteurs molĂ©culaires. Les techniques dâanalyse en composantes principales (PCA) et de dâanalyse de colinĂ©aritĂ© permettent dâidentifier les descripteurs les plus pertinents. un rĂ©seau de neurones supervisĂ©5 Ă deux couches (cachĂ©e et sortie) est employĂ© pour corrĂ©ler la structure molĂ©culaire Ă lâodeur. La base de donnĂ©es dĂ©crite prĂ©cĂ©demment est utilisĂ©e pour lâapprentissage. Un ensemble de paramĂštres est modifiĂ© jusquâĂ la satisfaction de la meilleure rĂ©gression.
Les rĂ©sultats obtenus sont encouragent, ainsi les descripteurs molĂ©culaires convenables corrĂšlent efficacement l'odeur des molĂ©cules. Câest la premiĂšre Ă©tape dâun modĂšle gĂ©nĂ©rique en dĂ©veloppement pour corrĂ©ler l'odeur avec les structures molĂ©culaire
Computer Aided Aroma Design. II. Quantitative structure-odour relationship
Computer Aided Aroma Design (CAAD) is likely to become a hot issue as the REACH EC document targets many aroma compounds to require substitution. The two crucial steps in CAMD are the generation of candidate molecules and the estimation of properties, which can be difficult when complex molecular structures like odours are sought and their odour quality are definitely subjective or their odour intensity are partly subjective as stated in Rossitierâs review (1996). The CAAD methodology and a novel molecular framework were presented in part I. Part II focuses on a classification methodology to characterize the odour quality of molecules based on Structure â Odour Relation (SOR). Using 2D and 3D molecular descriptors, Linear Discriminant Analysis (LDA) and Artificial Neural Network are compared in favour of LDA. The classification into balsamic / non balsamic quality was satisfactorily solved. The classification among five sub notes of the balsamic quality was less successful, partly due to the selection of the Aldrichâs Catalog as the reference classification. For the second case, it is shown that the sweet sub note considered in Aldrichâs Catalog is not a relevant sub note, confirming the alternative and popular classification of Jaubert et al., (1995), the field of odours
Comprehensive evaluation of antioxidant and antimicrobial properties of different mushroom species
Antioxidant properties of mushroom extracts sequentially isolated by cyclohexane, dichloromethane, methanol, and water from Phaeolus schweinitzii, Inonotus hispidus, Tricholoma columbetta, Tricholoma caligatum, Xerocomus chrysenteron, Hydnellum ferrugineum, Agaricus bisporus and Pleurotus ostreatus were evaluated by DPPH, ABTS+ scavenging capacity, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and FolinâCiocalteu total phenolic content (TPC) methods. The integrated values (âantioxidant scoresâ) for evaluating antioxidant potential of extracts and dry mushroom substances are proposed. Antimicrobial activity was screened against Gram-positive (Bacillus cereus), Gram-negative (Pseudomonas aeruginosa) bacteria and fungi (Candida albicans) by agar diffusion method. The highest antioxidant capacity values (in ÎŒM TE/g extract dw) were found for methanol fractions of P. schweinitzii (9.62 ± 0.03 in DPPH; 109 ± 3 in FRAP; 164 ± 1 in ABTS+; 340 ± 3 in ORAC assays) and I. hispidus (9.5 ± 0.04 in DPPH; 54.27 ± 0.46 in ABTS+; 88.31 ± 1.96 in FRAP; 290 ± 1 in ORAC assays). Extracts of other species possessed considerably lower antioxidant activities. The extracts of I. hispidus were more effective against tested microbial species than other mushrooms. In conclusion, our results show that some wild mushrooms might be promising dietary sources of natural antioxidants and antimicrobial agents
Oil and fatty acid accumulation during coriander (Coriandrum sativum L.) fruit ripening under organic cultivation
To evaluate the accumulation of oil and fatty acids in coriander during fruit ripening, a field experiment was conducted under organic cultivation conditions in Auch (near Toulouse, southwestern France) during the 2009 cropping season. The percentage and composition of the fatty acids of coriander were determined by gas chromatography. Our results showed that rapid oil accumulation started in early stages (two days after flowering, DAF). Twelve fatty acids were identified. Saturated and polyunsaturated acids were the dominant fatty acids at earlier stages (2â12 DAF), but decreased after this date. After this stage, petroselinic acid increased to its highest amount at 18 DAF. In contrast, palmitic acid followed the opposite trend. Saturated and polyunsaturated fatty acids decreased markedly and monounsaturated fatty acids increased during fruit maturation. It appears that the fruit of coriander may be harvested before full maturity
Innovative low-density blocks from amaranth pith for the thermal insulation of buildings
Amaranth is an annual herb native to temperate and tropical regions. Cultivated by Native Americans for the nutritional properties of its seeds, the latter are very digestible and also an interesting source of starch and proteins. For the future, amaranth appears as a promising raw material for the biorefinery of whole plants, all parts of the plant being potentially usable for different food and non-food applications.
This study especially aims to investigate the possible uses of pith from stems for material applications. For that, plants from the Amaranthus cruentus variety were cultivated in 2018 near Auch (Gers, France). Stems were manually harvested at plant maturity. Representing up to 90% w/w of the aerial part of amaranth plant, stems were then dried in a ventilated oven to facilitate their conservation. They are composed of a bark on their periphery and a pith fraction in their middle. The structure of stems was studied from ten samples, and the pith fraction was estimated manually to 27% w/w. Due to the difference in density between bark and pith fractions, a fractionation process associating grinding and blowing steps made possible the continuous separation between bark and pith.
As for sunflower and corn, amaranth pith particles have an alveolar (i.e. a microporous) structure similar to that of expanded polystyrene, and they reveal a very low bulk density (e.g. 48-52 kg/m3 for 4-16 mm particle size, and 58-61 kg/m3 for 1.25-2.50 mm particle size), making them a promising raw material for the thermal insulation of buildings. Cohesive and low-density insulation blocks were successfully obtained from amaranth pith, primarily mixed with a starch-based binder, through compression moulding at ambient temperature. Different operating conditions were tested, especially including (i) the size distribution of amaranth pith particles, (ii) the binder content, and (iii) the filling level of the mould. All produced samples were then characterized in terms of (i) density, (ii) bending and compression properties, and (iii) thermal insulation properties (measured through the hot wire method). All insulation blocks revealed low density, ranging from 90 to 140 kg/m3. Such innovative materials could be sustainable and viable options for the thermal insulation of buildings
Extraction of flavored coriander vegetable oil through extrusion technology
In an age where fossil resources are steadily depleting and environmental concerns have become an established subject of public and political discussions, the pursuit of sustainability is deeply entrenched in society. With regard to this and considering the consistently growing demand, the implementation of renewable resources in industrial processes could be a decisive solution. An interesting novel bioresource could be presented by Coriandrum sativum L., an annual herb from the family of Apiaceae and native to the eastern Mediterranean region. The coriander fruits are of particular interest, as they contain two distinct oil fractions. These comprise an essential oil with about 70% linalool and a vegetable oil, characterized by the presence of petroselinic acid, which constitutes over 70% of all fatty acids. Petroselinic acid, or cis-6-octadecenoic acid, presents a rare fatty acid common amongst the vegetable oils from Apiaceae crops. As a positional isomer of the more ubiquitous oleic acid, it may give rise to the synthesis of a series of novel, biobased compounds that could be of great interest to several industries. This renders the vegetable oil from coriander fruits particularly promising and as a consequence, the establishment of an efficient and economically favorable extraction process will constitute a major challenge for future research. Extrusion technology could present an attractive alternative to solvent extraction as it produces high quality vegetable oil that has not come into contact with any chemical substances. Further, the press cakes may find various profitable applications due to their essential oil content and antioxidant activity. Next to this, the extrusion cakes constitute natural biocomposites and could be transformed to value-added agromaterials through thermopressing. These biodegradable polymers could possibly replace less sustainable materials in automobile, building and furniture industries. The major disadvantage of mechanical pressing is considered its relatively low extraction yields and consequently a high residual oil content within the press cakes. A possible solution may lie within the application of seed pretreatments prior to the extrusion process. Therefore, the moisture content of coriander fruits was varied and the effect on the crushing behavior and extraction efficiency through single-screw, as well as twin-screw extrusion was assessed
Does the commercialization of sport has a decisive influence on the success of social sporting projects? : shown at the Dortmund fan project
Die Kommerzialisierung des Sports hĂ€ngt stark von dem Einfluss der Medien, der Politik und vom gesellschaftlichen Interesse ab. Erkannt wurde die Werbewirksamkeit des FuĂballsports in den 80er Jahren. Deutlich zeichnet sich eine dynamische Entwicklung in der Vermarktung des Sports ab. Zeitsynchron ergab sich durch die Tendenz zur erhöhten Gewaltbereitschaft in den FuĂballstadien die Notwendigkeit von sozialsportiven Projekten. VerbĂ€nde und Organisationen erkannten in der Entwicklung des Zuschauerverhaltens zunehmend die Gefahr fĂŒr das positive Image des FuĂballs. Dieser Problematik wurde durch die Schaffung von Fanprojekten entgegen gewirkt. Nur durch eine nachhaltige Ausrichtung und einer kontinuierlichen Weiterentwicklung können diese dauerhaft bestehen. Analysiert wird am Beispiel des Dortmunder Fan-Projekts, wie die Kommerzialisierung des FuĂballsports dazu beitrĂ€gt, sozialsportive Projekte erfolgreich umzusetzen. Durch Literaturanalyse und ein Experteninterview wird die These der Arbeit unterstĂŒtzt, dass die Kommerzialisierung des Sports direkten Einfluss auf sozialsportive Projekte hat
Potential interest of Tussilago farfara (L.) whole plant of Lithuanian and French origin for essential oil extraction
Tussilago farfara (L.), an Asteraceae of interest for traditional medicine, is known as a source of valuable essential oil (EO). The chemical composition of hydrodistilled EO of T. farfara flowers and stems was determined by GC and GC/MS techniques. Comparatively, quantitative and qualitative differences were observed in EO composition from both selected origins. The EO yields were 0.07 ± 0.01% and 0.09 ± 0.00% from Lithuanian and French origin. In total, 37 components were identified in Lithuanian and French oils. The major constituent in Lithuanian oil was n-tricosane (21.7 ± 0.1%) while in French oil it was 1-nonene (34.1 ± 0.00%
Bioactive Compounds and Antioxidant Properties of Myrrhis odorata Deodorized Residue Leaves Extracts from Lithuania and France Origins
Agricultural and industrial residues obtainedafter isolating essential oil very often constitute more than 99% of the raw material and represent a potential natural source for antioxidants and other valuable substances; however, nowadays they are poorly exploited. For the first time, this study investigated antioxidant properties and bioactive compounds in the deodorized residue extracts of Myrrhis odorataleaves collected in Lithuania and South of France in order to evaluate the potential of by-products obtained after essential oil isolation as a source for antioxidants. The extracts isolated with polar solvents were strong antioxidants, mainly due to the presence of kaempferol-7-o-glucoside and cynarin, which were reported in Myrrhis odoratafor the first time. Deodorized residues of mature leaves of Myrrhis odoratawere valued as an antioxidants bioresource for the first time
Extraction of Coriander Oil Using TwinâScrew Extrusion: Feasibility Study and Potential Press Cake Applications
This study presents an assessment of the vegetable oil extraction from coriander fruits through mechanical pressing, more specifically twin-screw extrusion. This comprises an evaluation of the oil recovery obtained and its respective quality, as well as the specific mechanical energy, representing an economical point of view. With regard to the extrusion optimization, the screw configuration, the deviceâs filling coefficient and the pressing temperature were varied. The screw configuration was shown to exhibit a key influence on the extraction efficiency and oil recoveries of at least 40 % were reached when the pressing zone was positioned immediately after the filter and consisted of 50 mm long, reverse screws with a -33 mm pitch. Furthermore, with a deviceâs filling coefficient of 39.4 g/h rpm and a pressing temperature of 120 °C, an oil recovery of 47 %, the highest of this study, was reached with concurrent low energy consumption. Next to this, operating parameters of 47.1 g/h rpm and 80 °C resulted in the production of a press cake with the lowest residual oil content (15 %) in this study, although this also involved a significant increase in the filtrateâs foot content. All the produced oils were of acceptable quality (<1.5 % acidity), showed high petroselinic acid content (73 %), and were pleasantly scented
- âŠ