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The abstract is available here: https://uscholar.univie.ac.at/o:1639163

This work aimed to characterize compositional and bioactive features of Aloe vera leaf (fillet, mucilage, and rind) and flower. The edible fillet was analysed for its nutritional value, and all samples were studied for phenolic composition and antioxidant, anti-inflammatory, antimicrobial, tyrosinase inhibition, and cytotoxic activities. Dietary fibre (mainly mannan) and available carbohydrates (mainly free glucose and fructose) were abundant macronutrients in fillet, which also contained high amounts of malic acid (5.75 g/100 g dw) and &alpha, tocopherol (4.8 mg/100 g dw). The leaf samples presented similar phenolic profiles, with predominance of chromones and anthrones, and the highest contents were found in mucilage (131 mg/g) and rind (105 mg/g) extracts, which also revealed interesting antioxidant properties. On the other hand, the flower extract was rich in apigenin glycoside derivatives (4.48 mg/g), effective against Pseudomonas aeruginosa (MIC = 0.025 mg/mL and MBC = 0.05 mg/mL) and capable of inhibiting the tyrosinase activity (IC50 = 4.85 mg/mL). The fillet, rind, and flower extracts also showed a powerful antifungal activity against Aspergillus flavus, A. niger, Penicillium funiculosum, and Candida albicans, higher than that of ketoconazole. Thus, the studied Aloe vera samples displayed high potential to be exploited by the food or cosmetic industries, among others.

The aim of this study was to evaluate the composition of aqueous extracts of in vitro shoot cultures and wild plants of Pterospartum tridentatum in order to promote the use of this plant material as a possible source of bioactive compounds. The extraction yield from wild plants compared with in vitro shoot cultures was lower. The total phenolic contents of in vitro shoots were significantly lower compared with those of wild plants. The phenolic profiles of in vitro shoots were very similar to those of wild plants, regardless of the source. However, taxifolin-6-C-glucoside, as well as rutin and isoquercitrin, were not present in extracts of in vitro shoots. An interesting result was the higher molar percentages of rhamnose and uronic acids detected in in vitro shoots compared with the wild plants, which can make the in vitro plant material very useful for obtaining these compounds. The authors acknowledge the financial support from CERNAS (projects P-Est-OE/AGR/UI0681/2014 and PEst-OE/AGR/UI0245/2014). info:eu-repo/semantics/publishedVersion

La composición química, minerales, azúcares neutros, compuestos fenólicos y capacidad antioxidante fueron analizados en la cascarilla de garbanzo. La cascarilla de garbanzo presentó 72% de fibra dietaria, del cual el 24.4% fue celulosa. Los compuestos fenólicos y actividad antioxidante de la cascarilla de garbanzo fueron evidentes, predominando los taninos condensados totales con 13.28 mgEC/g, donde la fracción soluble fue mayor respecto a la fracción ligada. El contenido de proteína y grasa fue de 4.5 y 0.4%. En conclusión, la cascarilla de garbanzo tiene propiedades nutricionales y funcionales que pueden ser consideradas en el diseño de nuevos productos alimenticios para mejorar la salud de los consumidores. Nutritional composition, phenolic compounds and antioxidant capacity of chickpea (Cicer arietinum) husk. The chemical composition, minerals, neutral sugars, phenolic compounds and antioxidant capacity were analyzed in the chickpea husk. Chickpea husk presented 72% of dietary fiber of which 24.4% was cellulose. The content of phenolic compounds and antioxidant capacity of chickpea husk was evident, predominating condensed tannins with a total content of 13.28 mgECat/g, of which soluble fraction was the higher than bound fraction. The content of protein and fat was 4.5 and 0.4 %, respectively. In conclusion, chick pea husk has nutritional and functional properties that can be considered in the design of new food products to improve the health of consumers.

Resumo O presente trabalho avalia e compara a composição química do folhelho branco e tinto, proveniente de castas típicas da região do Dão. A análise química mostra que o folhelho é constituído essencialmente por celulose, hemiceluloses, proteínas e extratáveis em água. Os compostos solúveis em água são constituídos principalmente por açúcares monoméricos (glucose e frutose) e por uma mistura complexa de hemiceluloses. A celulose do folhelho branco e tinto foi avaliada por difração de raios-X (DRX) e verificou-se que se trata de celulose I com um grau de cristalinidade de 66,1 e 72,8%, no folhelho tinto e branco, respetivamente. O teor de celulose no folhelho branco (12,5%) é bastante inferior quando comparado com o do folhelho tinto (20,8%). Os métodos espectroscópicos, nomeadamente RMN CP/MAS de 13C, permitiram verificar a presença de material ceroso e cuticular em ambos os folhelhos. Os extratáveis em diclorometano dos folhelhos são constituídos maioritariamente por ácidos gordos e terpenos. Abstract The present study evaluates and compares the chemical composition of white and red grape skins, from grapes of the typical caste Dão region. Chemical analysis shows that grape skins are constituted essentially by cellulose, hemicelluloses, and water extractable proteins. Water-soluble compounds consist primarily of monomeric sugars (glucose and fructose) and of a complex mixture of hemicelluloses. The structure of cellulose from white and red grape skins was evaluated by X-ray diffraction (DRX) and found to be cellulose I polymorph with a crystallinity degree of 66.1 and 72.8% for red and white grape skin celluloses, respectively. The content of cellulose in white grape skins (12.5%) is significantly lower when compared to that in red grape skins (20.8%). Spectroscopic methods, as 13C CP/MAS NMR, allowed the detection of waxy material in both cuticular tissues of grape skins. Dichloromethane extracts of grape skins consist mostly of fatty and triterpenic acids.

National audience

[ESP] El fruto del melón (Cucumis melo L.) es muy apreciado por los consumidores por su sabor dulce y aroma agradable y su cultivo es de gran importancia en España y en particular en la Región de Murcia. C. melo L. se caracteriza por su gran diversidad genética y de comportamiento fisiológico lo que lo convierte en un modelo ideal para el estudio del metabolismo y la maduración en frutos carnosos. El objetivo de esta tesis doctoral fue identificar los Quantitative Trait Loci (QTLs) asociados a parámetros de calidad del melón y caracterizar algunos de sus efectos, especialmente relacionados a la producción de compuestos volátiles aromáticos y textura del fruto del melón. También se estableció la relación entre el comportamiento fisiológico de los frutos y algunas de sus características. Se utilizaron líneas casi-isogénicas o NILs de melón con distinto comportamiento fisiológico y obtenidas del cruzamiento entres dos parentales no climatéricos, el cultivar español ‘Piel de Sapo’ (PS) tipo inodorus y la accesión exótica coreana tipo conomon PI 161375 ‘Shongwan Charmi’ (SC). Las NILs contenían una introgresión homocigótica casi única del parental SC en el fondo genético del parental PS. Los análisis realizados en los frutos de melón han permitido comparar las NILs con respecto del parental PS y así detectar diferencias mediante diversas técnicas estadísticas univariante y multivariantes con el fin de poder identificar QTLs de interés en el mapa genético del melón y localizar aromas discriminantes. El comportamiento climatérico de la NIL 6M1 y del cultivar ‘Védrantais’ (leve y moderado, respectivamente) estuvo asociado a una mayor producción de ésteres (acetato y no acetato) y compuestos derivados del azufre, mostrando una dependencia al menos parcial del etileno para su síntesis. Aldehídos, alcoholes y cetonas estuvieron asociados al comportamiento no climatérico del control PS, cultivar ‘Nicolás’ y de las NILs SC10- 2 y SC7-1, mostrado su carácter etileno-independiente. Se han identificado QTLs asociados a la firmeza de la pulpa y la producción aromas volátiles en NILs de melón con introgresiones en los grupos de ligamiento III/VI (comportamiento climatérico) o VII y X (comportamiento no climatérico). Un QTL (ff7.2) fue mapeado en el LG VII asociado a la mayor firmeza de la pulpa de la NIL SC7-1 y relacionada con el mayor contenido en componentes estructurales de la pared celular como galactosa y residuo de α-celulosa. Otro QTL relacionado a una mayor degradación de pectinas fue asociado a los QTLs del climaterio de la NIL SC3-5-1, mientras que otro QTL relacionado con la introgresión que produce el climaterio (localizada en el LG III) estuvo asociado a la producción de ésteres. Otros treinta y dos QTLs; doce identificados en el LG VII y veinte en el LG X fueron asociados a la producción de ciertos aromas volátiles sirviendo como potenciales biomarcadores de mayor firmeza de la pulpa (especialmente aldehídos producidos vía aminoacídica) y otras diferencias texturales (especialmente relacionadas con la síntesis compuestos derivados del azufre y compuestos derivados de la metionina) entre NILs de melón no climatéricas. Las NILs de melón con distinto comportamiento fisiológico han resultado de alto interés para dilucidar el carácter etileno-dependiente, etileno independiente o solo parcialmente etileno dependiente de aromas volátiles y textura, así como la interrelación entre dos de lo parámetros más importantes que definen la características de este fruto y por ende a ampliar el conocimiento acerca del etileno y sus efectos sobre la calidad global y parcial de la fruta en general y del melón en particular. [ENG] Melon fruit (Cucumis melo L.) is highly appreciated by consumers for its sweet taste and pleasant aroma, being a crop of great importance in Spain and particularly in the Region of Murcia C. melo L. is characterized by its great genetic diversity and physiological behavior which makes it a ideal model for the study of metabolism and ripening in fleshy fruits. The aim of this thesis was identify Quantitative Trait Loci (QTLs) associated with melon quality parameters and characterize some of its effects, especially associated with the production of aromatic volatile compounds and texture of melon fruit. The relationship between the physiological behavior of the fruit and some of its characteristics is also established. Near-isogenic lines or NILs of melon with different physiological behavior and obtained by crossing of two non-climacteric parents, the Spanish cultivar inodorus type ‘Piel de Sapo’ (PS) and the Korean exotic accession PI 161375 conomon type ‘Shongwan Charmi’ (SC) were used. The NILs contained a homozygous introgression almost unique of parental SC in the genetic background of parental PS. The analyses realized in melon fruits has allowed comparing the NILs with the parental PS and so detect differences by means of several univariate and multivariate statistical techniques in order to identify QTLs of interest in the melon genetic map and locate discriminant aromas. The climacteric behavior of NIL 6M1 and cultivar ‘Védrantais’ (slight and moderate, respectively) was associated with increased production of esters (acetate and no acetate) and sulfur-derived compounds, showing at least a partial ethylene dependence for their synthesis. Aldehydes, alcohols and ketones were associated with non-climacteric behavior of the control PS, cultivar ‘Nicolas’ and NILs SC10-2 and SC7-1, shown its ethylene-independent character. QTLs associated with flesh firmness and aroma volatile production in melon NILs with introgressions in the linkage groups III/VI (climacteric behavior) or VII and X (non-climacteric behavior) had been identified. A QTL (ff7.2) located in the LG VII associated with higher flesh firmness in NIL SC7-1 was mapped and related to the higher content of cell wall structural components, as galactose and α-cellulose residue. Another QTL associated with increased pectin degradation was associated to climacteric QTLs of the NIL SC3-5-1, whereas another QTL related to introgresión which produce climacteric (located in LG III) was associated to esters production. Other thirty-two QTLs, twelve identified in the LG VII and twenty in the LG X were associated to the production of certain volatile aromas serving as potential biomarkers of higher flesh firmness (especially aldehydes produced via aminoacid) and other textural differences (especially related to synthesis of sulfur-derived compounds and compounds obtained via methionine) between non climacteric melon NILs. Melon NILs with different physiological behavior have been results of great interest to elucidate the ethylenedependent, ethylene-independent or only partially ethylene-dependent character of aroma volatiles and texture, as well as the interrelation among two of the most important parameters that define the characteristics of this fruit, and therefore to increase the knowledge about the ethylene and its effects on global and partial fruit quality in general and melon in particular., Universidad Politécnica de Cartagena

Two experiments were conducted to investigate the degradation of cell-wall sugars from soya bean meal (in situ), and soya bean endosperm and hulls (in vitro). Soya bean meal, soya bean endosperm, and soya bean hulls were extracted with different chemicals to obtain the cell-wall fraction. Soya bean meal cell walls were incubated in the rumen of a fistulated cow. The individual cell-wall sugars were degraded at different rates: galactose (13.6% h−1), arabinose (7.8% h−1), uronic acids (5.1% h−1), xylose (3.5% h−1) and glucose (3.2% h−1). Microscopic evaluation of the cell walls and degraded material revealed the presence of two cell wall types, with distinctly different degradation characteristics: one originating from the hull (thick, slowly degraded) and one from the endosperm (thin, rapidly degraded). Furthermore, the cell-wall sugar composition of endosperm and hull cell walls was different, most markedly for galactose (281 vs. 12 g kg−1) and glucose (132 vs. 508 g kg−1). The degradation of endosperm and hull cell walls was measured in vitro by use of in vitro cumulative gas production. Degradation rates of the individual cell-wall sugars for hull cell walls were similar (ranging from 2.4% to 4.6% h−1). For endosperm cell walls, the degradation rates of the individual sugars were different but with the same ranking as in the in situ experiment (ranging from 20.9% to 7.0% h−1). It was concluded that for soya bean meal cell walls, the cell-wall sugar degradation pattern is influenced by the presence of two cell-wall types (hull and endosperm cell-wall), which differ in their rate of degradation and sugar composition. The difference in cell-wall sugar degradation pattern between hull and endosperm cell walls is likely to be caused by a combined effect of particle size and cell-wall thickness.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Along the chain of banana processing a large amount of waste with potential for exploitation is generated. This study aimed to study the potential use of flour banana peel (Musa AAA) type Cavendish in obtaining pectin and determine the phenolic composition majoritarian this flour. Bananas with "degree of skin color, 5 ", according to Von scale Loesecke were sanitized and manually peeled. The shells were bleached and then dried in a tray drier with forced air to constant weight and then ground to powder mill to obtain flour. Then, the following determinations were made: moisture; ether extract; crude protein soluble and insoluble fiber, ash; glicidic fraction; calorific value and water activity. To study the extraction, two extracting agents were evaluated (citric acid and oxalic acid - ammonium oxalate, AOOA), and using a central composite design (CCD) with three independent variables (temperature, time and pH or concentration, depending on the extractor), totaling eighteen experiments for each extracting agent. From the adjusted models were determined appropriate extraction conditions: citric acid (80 ° C, 0.7 %, 80 min) and AOOA (0.25% ammonium oxalate, 75 oC, pH 2.8, using oxalic acid, 50 min). Pectins were analyzed for their chemical, physical, and structural. For purposes of comparison sample was also analyzed commercial citrus pectin. With regard to the phenolic content of the flour, the extracts exhibited high phenolic content (about 29 mg g- as GAE), mainly flavonoids polymerized (approximately 3952 mg.kg- 1), flavonol glycosides, procyanidin dimers of type B and flavan -3- ols monomer (about 126 mg.kg- 1). The high phenolic content in the extracts is probably responsible for the high antioxidant activity evidenced by three different methods: FRAP, 14 μM.g- 1; ABTS , 242 μM.g- 1 and ORAC, 436 μM.g- (expressed in Trolox equivalent). The results indicate that the banana peel (Musa AAA) type Cavendish feasible for the process of obtaining the meal and, due to the high fiber content, can be a great alternative to the xvenrichment of food products with raw material cost. Although the results show the banana peel as a potential source of pectin, the pectin extracted in this study did not meet the requirements of FAO standard commercial pectins. However the results show the use of banana peel as a cost effective source of bioactive phenolic compounds. Ao longo da cadeia de processamento da banana uma grande quantidade de resíduos com potencial de aproveitamento é gerada. O presente trabalho teve como objetivo estudar o potencial de utilização da farinha de casca de banana (Musa AAA) tipo Cavendish na obtenção de pectina e determinar a composição fenólica majoritária nesta farinha. As bananas com grau de coloração da casca 5 , segundo escala de Von Loesecke, foram sanitizadas e descascadas manualmente. As cascas foram branqueadas e então secas em secador de bandejas com circulação forçada de ar até massa constante e, trituradas em moinho de facas, para a obtenção da farinha. Em seguida, foram feitas as seguintes determinações: umidade; extrato etéreo; proteína bruta; fibras solúveis e insolúveis; cinzas; fração glicídica; valor calórico e atividade de água. Os resultados indicam que a casca de banana (Musa AAA) tipo Cavendish é viável para o processo de obtenção da farinha e, devido ao alto teor de fibras, pode ser uma ótima alternativa para o enriquecimento de produtos alimentícios com uma matéria-prima de baixo custo. Para o estudo de extração, dois agentes extratores foram avaliados (ácido cítrico e ácido oxálico-oxalato de amônio - AOOA), sendo utilizado um Delineamento Composto Central (DCC) com três variáveis independentes (temperatura, tempo e pH ou concentração, dependendo do extrator). A partir dos modelos ajustados, foram determinadas condições adequadas de extração: ácido cítrico (80 oC, 0,7 %, 80 min) e AOOA (0,25 % de oxalato de amônio, 75 oC, pH 2,8, utilizando ácido oxálico, 50 min). As pectinas foram analisadas quanto às características químicas, físicas, e estruturais. Apesar de os resultados mostrarem a casca de banana como uma potencial fonte de pectina, as pectinas extraídas neste estudo não atendem às exigências da Food and Agriculture Organization of the United Nations (FAO) para pectinas de padrão comercial. Com relação à composição fenólica da farinha, os extratos exibiram elevado conteúdo fenólico (cerca de 29 mg.g -1, como equivalente de ácido gálico - GAE), principalmente flavonoides polimerizados xiii(cerca de 3952 mg.kg-1), flavonóis glicosídeos, dímeros de procianidina tipo B e flavan-3-óis monoméricos (em torno de 126 mg.kg-1). O elevado conteúdo de fenólicos nos extratos é, provavelmente, o responsável pela elevada atividade antioxidante evidenciada por três diferentes métodos: Reduçao de íons de ferro (FRAP),14 μM.g-1; Captura do radical livre ABTS, 242 μM.g-1 e Ensaio da capacidade de absorção do radical oxigênio (ORAC), 436 μM.g-1 (expressos em TROLOX equivalente). Logo os resultados sugerem o uso da casca de banana como fonte rentável de compostos fenólicos bioativos.

International audience; Soil microorganisms play a pivotal role in soil organic matter (SOM) turn-over and their diversity is discussed as a key to the function of soil ecosystems. However, the extent to which SOM dynamics may be linked to changes in soil microbial diversity remains largely unknown. We characterized SOM degradation along a microbial diversity gradient in a two month incubation experiment under controlled laboratory conditions. A microbial diversity gradient was created by diluting soil suspension of a silty grassland soil. Microcosms containing the same sterilized soil were re-inoculated with one of the created microbial diversities, and were amended with C-13 labeled wheat in order to assess whether SOM decomposition is linked to soil microbial diversity or not. Structural composition of wheat was assessed by solid-state C-13 nuclear magnetic resonance, sugar and lignin content was quantified and labeled wheat contribution was determined by C-13 compound specific analyses. Results showed decreased wheat O-alkyl-C with increasing microbial diversity. Total non-cellulosic sugar-C derived from wheat was not significantly influenced by microbial diversity. Carbon from wheat sugars (arabinose-C and xylose-C), however, was highest when microbial diversity was low, indicating reduced wheat sugar decomposition at low microbial diversity. Xylose-C was significantly correlated with the Shannon diversity index of the bacterial community. Soil lignin-C decreased irrespective of microbial diversity. At low microbial diversity the oxidation state of vanillyl-lignin units was significantly reduced. We conclude that microbial diversity alters bulk chemical structure, the decomposition of plant litter sugars and influences the microbial oxidation of total vanillyl-lignins, thus changing SOM composition.

In vivo pectin solubility was examined in ripening and chill-injured tomato fruit with down-regulated polygalacturonase (PG, EC 3.2.1.15) activity and untransformed wild-type fruit by analyzing a pressure-extracted fluid of apoplastic origin. Pectin concentration in the apoplastic fluid increased threefold during ripening and was not affected by endogenous PG. In contrast, PG strongly affected pectin concentration in a bulk pericarp fluid obtained after tissue disruption. There was a 14-fold increase in bulk pectin levels during ripening of PG-antisense fruit and a 36-fold increase in wild-type. Pectins soluble in the apoplastic fluid decreased slightly during storage of fruit at 5ºC for 14 days but increased considerably upon subsequent transfer to 15ºC. Concentration of monomeric galactose in the apoplastic fluid increased during ripening from 41 to 67 µg mL⁻¹. Galactose levels were threefold to fourfold higher in the bulk than in the apoplastic fluid. Low-temperature storage caused a 50% reduction in the galactose present in the bulk fluid and a 20% reduction in apoplastic concentration of galactose. These results indicate that pectin dissolution in ripening tomato fruit is PG-independent even though the enzyme is catalytically active in ripe fruit. Low-temperature storage reduces in vivo pectin solubility, an effect that is reversed upon transfer to higher temperature following cold storage

A detailed characterization of dissolved carbohydrates in the Siberian rivers and shelf areas, the Kara and Laptev Seas, the central Arctic Ocean, Fram Strait, and Greenland Sea is presented. Highest concentrations of total carbohydrates (25 mM C on average) were measured in the samples of the Russian rivers. A strong decrease of the concentrations occurred during the transition into the marine environment (5.3 mM C on average). In deep waters, the total carbohydrate concentrations were below 2 mM C. The main component of dissolved carbohydrates was glucose, which was well suited for the characterization of the diagenetic state of DOM. Terrigenous and diagenetic old marine DOM had very low glucose proportions between 20 and 28% of total carbohydrates. In contrast, freshly produced DOM was characterized by high glucose proportions of up to 86%. Indicators for diagenetic modifications were also fucose, rhamnose, and arabinose, whose proportions increased with increasing diagenetic degree to approx. 40%. The composition of refractory carbohydrates was determined by extraction of recalcitrant organic matter from the seawater using a combination of XAD-2 and -4 adsorption resins. With increasing age of DOM, the proportion of the humic substances of the total DOC and of the total carbohydrates increased from 45% in surface samples to 67% in the deep sea. Part of refractory carbohydrates may be composed of chemically modified carbohydrates, which are not accessible with the chromatographic method. More than the half of the XAD-extractable sugars of surface samples and more than 70% of deep sea samples were found in the unpolar fraction. It was concluded that the majority of refractory carbohydrates were bound or associated to unpolar compounds of small molecular size. Using the ratio of the sum of the molar proportions of the deoxysugars and the sum of arabinose and xylose, the extracted humic substances were characterized with respect to their diagenetic degree.

The objective of this work was to evaluate the efficiency of delinting time of cottonseeds through the electrical conductivity and the quantity of neutral sugars and uronic acids leaked from the seeds during imbibition in water, in function of the fractioning in water and the artificial ageing. The seeds were delinted with commercial sulphuric acid for 1.5 and 4.5 minutes, separeted according to the sedimentation fractions in water and submitted to artificial ageing for 0, 72 and 96 hours. Electrical conductivity, contents of neutral sugars and uronic acids were determinated from the exudate resulting from the seeds imbibition in relation different treatments. The results showed that the delinting time for 1.5 minutes provided higher values of electrical conductivity, higher contents of neutral sugars and lower contents of uronic acids in relation with delinted seeds.

Seasonal changes in composition and properties of a high dietary fibre product from grapefruit peel were studied. Total dietary fibre decreased in January as compared to September (586-686 g kg-1). Main constituents from soluble fibre were: uronic acids (172-233 g kg-1), arabinose (13-41 g kg-1), galactose (4-11 g kg-1), glucose (5-10 g kg-1) and xylose (2-3 g kg-1). Insoluble dietary fibre (385-392 g kg-1) did not significantly change during the season. Its main constituents were: Klason lignin (29-37 g kg-1), uronic acids (3370 g kg-1) and neutral sugars: glucose (149-196 g kg-1), mannose (4550 g kg-1), xylose (25-38 g kg-1), galactose (20-22 g kg-1) and arabinose (16-45 g kg-1). Total neutral sugars from dietary fibre decreased over the harvest period (315-383 g kg-1) and an inverse trend was observed in total free-sugars from samples (49-85 g kg-1). Both, water holding capacity (7.0-9.3 g water g-1 dry sample) and glucose retardation index (7.0-25.3%) decreased from early stages in fruit development until late in the harvest season. Seasonal changes in grapefruit peel should be taken into account, in order to standardise the quality of rich fibre products.