Tackling the cell wall of the grape berry

Abstract: The cell wall (CW) is the dynamic border of plant cells. In grape berries, the CW decisively accounts for the difference between the pulp and skin cells, with direct consequences on the grape characteristics, wine quality and wine-making methods. The softening of mature berries results from the depolymerisation and solubilisation of CW polymers. Modifications of grape pulp and skin CW provide the flexibility for cell expansion during fruit growth and to modulate the final texture. Wine making and berry processing methods are directly related with the absence, in white wines, or the presence, in red wines, of skin CW in the fermenting must. Anthocyanin extraction depends directly on skin yielding of the pigment upon CW degradation. During fruit growth and ripening, the cooperative action between different enzyme families is capital in CW metabolism. The sequencing and public availability of the Vitis genome allowed us to focus on individual pathways, to profile the expression pattern of isoforms associated with each tissue, developmental phase or stress response, anticipating the effects on berry (and wine) production and quality. Retrieving the sequences of genomic coding regions and the predicted enzymes that act on the Vitis, CW allows us for the first time to tackle the grape berry Cell Wallom

Structure and function of the seed coat of Theobroma cacao L. and its possible impact on flavour precursor development during fermentation

Seed coats are known to regulate the transfer of substances between the embryo and both the mother plant and the environment. The permeability of the seed coat of the fermenting seeds of Theobroma cacao may significantly affect its final flavour quality. Many studies suggest that the flavour quality is genetically determined and uniform within one clone. This implies that the flavour quality can only be inherited exclusively from the mother plant. Consequently, factors affecting flavour quality should be located in the maternal tissues surrounding the seed. As only the fruit pulp and the seed coat are exclusively maternal in origin, whereas the embryo and the endosperm are the progeny of both parents, the flavour quality may be associated with transport characteristics of the seed coat. In this context the influence of the seed coat on the transport of acetic acid, the main product of fermentation is of high relevance.We investigated the transport characteristics of the seed coat of T. cacao with modern light- and fluoroscence microscopic methods. Tracers were used in order to evaluate the potential impact of structures such as barriers and entry sites for the transport of water and solutes. Our morphological, histochemical and microspectrophotometrical data and the interpretation of the tracer distributions demonstrate that certain structures of the seed coat strongly influence the course of transport processes in the mature seed coat of T. cacao. These include the inner contact zone of fruit pulp and seed coat, hilum, sclereid layer, hypostase, micropyle and endosperm cuticle. Under natural conditions these structures may prevent desiccation and loss of nutrients of the recalcitrant seed. During fermentation the mentioned structures appear to affect the influx of acetic acid, in analogy to water and solutes. Insufficient or excessive acidification impedes sufficient formation of flavour precursors resulting in a flat or acid taste. Asynchronous and uneven infiltration of acetic acid into the cotyledon cells will lead to inconsistent and suboptimal flavour quality. In conclusion we suggest that flavour quality of the fermented seeds is predominantly due to transport kinetics of water and solutes during the fermentation process rather than a reflection of genetically coded differences in storage proteins

Effect of irrigation on berry and skin cell wall composition in the grape varieties Touriga Nacional and Trincadeira

Mestrado Vinifera EuroMaster - Instituto Superior de AgronomiaThe main objective of this study was to determine how water availability effected the composition of both the grape berry and the skin cell wall of two Portuguese grape varieties, Touriga Nacional and Trincadeira. Different vines situated in the Centro Experimental de Pegões, 70 Km East from Lisbon, Portugal, were subjected to Nonirrigated (NI, no water applied) and Fully-irrigated (FI, 100% of evapotranspiration rate) treatments throughout the growing season for each variety. Berries were harvested and sampled on 20th September 2010 from the four plots and the yield and quality parameters were tested. Differences between the treatments were noted with grapes from irrigated plants showing significantly higher berry weight, and volume. Whereas the non-irrigated berries showed higher levels of anthocyanin content, colour intensity, total phenolics and total acidity, than the fully irrigated. There were also differences noted between varieties in several parameters, mainly with Touriga Nacional showing a higher content in the phenolic compound

Non-extractable Procyanidins and Lignin are Important Factors in the Bile Acid Binding and Radical Scavenging Properties of Cell Wall Material in some Fruits

The cell wall components and the food functions of alcohol-insoluble solids (AIS) of Chinese quince, quince, hawthorn, apple, pear and blueberry fruits were analyzed. Chinese quince contained characteristically high contents of cellulose, lignin, and non-extractable procyanidins (NEPCs). On the other hand, the quince AIS contained the highest proportion of NEPCs, the highest mean degree of polymerization (mDP), the strongest radical scavenging activity, and strong bile acid binding activity. In fruit AIS, the lignin and NEPC contents both showed positive correlations with the bile acid binding and radical scavenging activities. The value for mDP x NEPC content was a good index for the radical scavenging activity. The results suggest that highly polymerized NEPCs and lignin are important factors of cell wall components of fruits to having a high functionality, and Chinese quince and quince are interesting fruits from this view point.ArticlePLANT FOODS FOR HUMAN NUTRITION. 66(1):70-77 (2011)journal articl

Extractability of Low Molecular Mass Flavanols and Flavonols from Red Grape Skins. Relationship to Cell Wall Composition at Different Ripeness Stages

[EN] Flavonol and flavan-3-ol extractabilities from red grape skins were evaluated in Tempranillo grapes harvested at different ripeness stages and with different soluble solid contents within each stage. Flavan-3-ol extractability is related to ripeness stage and also to cell wall composition, mainly to arabinogalactans (AG), mannans, rhamnogalacturonans-I (RG-I), homogalacturonans (HG), xyloglucans (XG), and total polysaccharides content, which are negatively correlated to flavan-3-ol extractability, whereas soluble solid content did not exert any influence on their extraction. Moreover, procyanidin extraction is more strongly related to cell wall composition than prodelphinidin extraction. Flavonol extractability was not influenced by insoluble material contents; although some cell wall components presented a relationship with flavonol extractability, the presence of AG and mannans would decrease total flavonol extractability, whereas protein is positively related to total and major flavonol compounds (i.e., quercetin and myricetin derivatives). The different behaviors observed between those two groups of polyphenol compounds could be due to different tissue and cellular location

Production of mannooligosaccharides from pineapple pulp and pine sawdust using Aspergillus niger derived Man26A and determination of their prebiotic effect

Lignocellulosic biomass is the most abundant source of renewable biomass on earth. Lignocellulosic biomass consists of cellulose, hemicelluloses and lignin. These can be used as a source of renewable fuel as well as other value-added products . Mannans are part of the hemicellulose fraction of lignocellulosic biomass and are the major hemicellulosic polysaccharide fraction in softwoods, where they are found as galactoglucomannans and as glucomannans. Mannans are also found in hardwoods in the form of glucomannans. Mannans can be enzymatically hydrolysed using endo-mannanases to produce of short chain mannooligosaccharides (MOS). MOS have received significant attention for their prebiotic properties, as they promote the growth of probiotic bacteria, which have positively affects on gut health. This study focused on the production of prebiotic MOS from lignocellulosic biomass waste (LBW) and an evaluation of the prebiotic potential of the produced MOS. An Aspergillus niger derived endo-mannanase, Man26A, was fractionated and biochemically analysed. Purified Man26A had a fold purification of 1.25 and a yield of 41.1%. SDS-PAGE analysis of the enzyme revealed that it had a molecular weight of 46 kDa. The pH and temperature optima of Man26A were determined and the pH optimum was found to be pH 4.0 (but the enzyme displayed high activity over a broad acidic pH range, with up to 90% of the activity retained between pH 3.0 and 7.0). The temperature optimum was 50℃. The enzyme was shown to have the highest specific activity on locust bean gum (52.27 U/mg) and ivory nut mannan (57.25 U/mg), compared to guar gum (29.07 U/mg), which indicated that it was affected by the substitution pattern of the mannans. Man26A produced MOS of different diversity on model mannan substrates, where the MOS produced were mannobiose, mannotriose, and mannotetraose for ivory nut mannan, mannobiose, mannotriose, mannotetraose, and mannopentaose and MOS with a higher degree of polymerisation for locust bean gum, and mannobiose, mannotriose, mannotetraose, mannopentaose, and mannohexose and MOS with a higher degree of polymerisation for guar gum, as determined by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Pretreatment and characterisation of pineapple pulp (PP) and pine sawdust (PSD) was conducted, and the impact of the pretreatment procedures was analysed using Megazyme sugar kits, thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and microscopic analysis using scanning electron microscopy (SEM) and light microscopy. Compositional analysis of the carbohydrates present in both substrates revealed that they had a glucan content of 36.41 and 50.47% for untreated PP and PSD, respectively. Their respective mannan content was 6.74 and 11.59% and was deemed sufficient for the production of MOS via enzymatic hydrolysis. TGA analysis revealed that untreated and sodium chlorite-acetic acid delignified samples decomposed at approximately the same time, and had a negligible ash content at 600℃, while delignified plus phosphoric acid swollen substrates decomposed at a faster rate, but had a residual ash content at 600℃. FTIR analysis of the substrates revealed slight changes in the structures of untreated and pretreated samples. SEM analysis of PP and PSD showed a change in the morphology of the substrates with subsequent pretreatment steps. Histochemical analysis for lignin for PP and PSD showed successful delignification upon pretreatment. Untreated and sodium chlorite delignified PP and PSD released low amounts of reducing sugars compared to delignified + phosphoric acid swollen substrates. The delignified + phosphoric acid swollen substrates were used for further experiments. MOS produced from delignified and phosphoric acid swollen (Del + PAS) PP and PSD at 0.1 mg/ml enzyme loading and 80 mg/ml (8% (w/v)) substrate concentration, ran between mannose and mannobiose and between mannobiose and manotriose on TLC, with low concentrations of MOS running between mannotetraose and mannopentaose. HPLC analysis of the MOS revealed that Del + PAS PP produced mannose to mannohexose, while Del + PAS PSD produced mannose, mannobiose, and mannotetraose. The MOS were analysed using FTIR, to determine whether the MOS produced contained any acetyl groups, which were present for Del + PAS PSD at 1706 cm-1. The MOS were stable at different pHs, and at temperatures below 200℃. The MOS were also found to be stable in a simulated gastrointestinal environment, in the presence of bile salts and digestive enzymes. The prebiotic effect of the MOS derived from Del + PAS PP and PSD was evaluated. MOS had a proliferative effect on probiotic bacteria (Lactobacillus bulgaricus, Bacillus subtilis and Streptococcus thermophilus). The production of short chain fatty acids (SCFAs) was evaluated on TLC, where no SCFAs were observed on the plate. The effect of MOS on the adhesion ability of bacteria revealed that they do not positively influence the adhesion of probiotic bacteria. The antioxidant activities of 1 mg/ml MOS produced from both substrates were determined to be approximately 15% using the ABTS radical scavenging assay, compared to a radical scavenging activity of 45% for the 0.02 mg/ml gallic acid standard. This study demonstrated that biomass waste could be used to produce prebiotic MOS, which play a positive role in gut ecology and provide health benefits.Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 202

Ontogenia dos órgãos reprodutivos e da plântula de Syagrus inajai (Spruce) Becc. (Arecacae)

Syagrus inajai is a palm that occurs in the Amazonian Biome, in different plant physiognomies, such lowland rain forest, slope and gallery forests, as well as in open areas such as clearings and roadsides. It produces large quantities of edible fruits. The purpose of this work is to carry out an ontogenic study of S. inajai from gynoecium to seedling, in terms of its its morphoanatomy. The observations and collection of botanical material were carried out in 2009 and 2010, in a green area of the Campus of the Universidade Federal do Amazonas - UFAM, Manaus, Amazonas, Brazil, which is situated in a region of baixio forest, at coordinates 3 0 05’ 45.84” S and 59 0 58’ 43.69 ”. Thirty individual specimens of S. inajai were collected for analysis. The aim of the first chapter is to characterize the morphoanatomy of the inflorescence of S. Inajai, enabling a better knowledge of the species studied and an understanding of the processes of formation of the fruit and seed. The inflorescences are branched to one order, pedunculate, and interfoliar, measuring 62-82 cm in length, with woody bracts with longitudinal grooves on the external surface, and flowers in triads. The number of flowers to each inflorescence varies from 5,904 to 17,316 for staminate flowers, and from 180 to 3,528 for pistillate flowers. Staminate flowers with six stamens and one vascular bundle each; three-lobed pistillodium, vascularized pistillodium. Its pistillate flowers have six staminodia joined to form a circle, syncarpic, tricarpellary, trilocular gynoecium, one ovule to each locule, synascidiate in the ovary, and plicated above. Tripartite stigma, apical and sessile, with epidermis composed of elongated papillary cells, pattern of epidermis that is maintained throughout the stylar canal. Bitegmented, anatrope, pachychalazal ovule. In the second chapter, the aim was to carry out a morphoanatomical study of the development, from gynoecium to the developed fruit, and to measure the approximate time to occurrence of the separate events in this process. From the seminal primordium, the ovules are anatropous. Hypostasis with cells containing phenolic content is prolonged during development, including the entire ovule, throughout the length of the pachychalazy. The ovary has two meristemic regions: a peripheral meristem region, adjacent to the outer epidermis, which gives origin to the fibrous mesocarp; and an internal meristemic region, which involves the internal seminal cavity and is responsible for the thickening of the endocarp, forming the endocarp sensu lato, of mixed origin. Sclerification of the endocarp initiates in the fruit at around 80 days, occurring centripetally. The endosperm is of the multicellular coenocytic type, with formation of the cell walls occurring centrifugally. The operculum is comprised of cells of the outer and inner integuments, and by sclerified cells of the obturator. The first cell division of xi the zygote occurs around 30 days after the start of development of the endosperm. The development time of the fruit is approximately 240 days. The third chapter gives a morphoanatomical characterization of the embryo of Syagrus inajai, in different phases of its development, seeking to contribute with information on the embryonic development of palms, and further our understanding of the germinative process of plants of the family Arecaceae.The development process of the embryo, until the moment of dispersion, takes approximately 220 days, and is divided into four stages: proembryo, globular embryo, lateral cordiform and torpedo. The embryo is small, linear, and derived from the terminal cell of the proembryo, arising from mitotic divisions in the apical cell. The embryonic axis is located in the proximal region, aligned parallel to the length of the embryo. The single cotyledon is formed by the ground meristem, procambium and protoderm. The procambium supplies the embryonic axis and the haustorium. The fourth chapter aims to describe the morphoanatomy of the germinative process of S. inajai and to determine its average duration, and also to identify the ergastric substances present in the embryo, haustorium and endosperm, and to perform centesimal analysis of the seed.The germination of S. inajai starts at around 101 days after seeding, with the formation of the germinative button. The morphological events that followed were: lengthening of the hyperphyll, intumescence of the cotyledonary sheath, emergence of the primary root and first cataphyll, emergence of the second cataphyll and eophyll. Lengthening of the embryo axis was observed after the emergence of the germinative button, during the process of lengthening of the hyperphyll. It was possible to see the primary root with the naked eye after the intumescence of the cotyledonary sheath, at which moment the two cataphylls and the eophyll were differentiated in the cotyledonary sheath. Starch was observed in the embryo before germination, but its quantity increased in the parenchyma cells after the formation of the germinative button. The seed presented 30% lipids in its concentration at the moment of dispersion. The time from opening of the peduncular bract to dispersion of the fruit is 240 days. The opening of the pistillate flower occurs 20 days after the opening of the peduncular bract; the fruit takes around 240 days to form, and the embryo 220 days.Syagrus inajai (Spruce) Becc. é uma palmeira que ocorre no Bioma Amazônico, em diferentes fisionomias vegetais, como: floresta de terra firme, vertente e baixio, além de áreas abertas, como beira de estradas. Produz grande quantidade de frutos, os quais, são comestíveis. O presente trabalho teve como objetivo realizar o estudo ontogênético dos órgãos reprodutivos e da plântula de S. inajai, através da morfoanatomia. As observações e coleta do material botânico foram realizados nos anos de 2009 e 2010 em área verde do Campus da Universidade Federal do Amazonas - UFAM, Manaus, Amazonas, Brasil, em área de baixio, ao redor das coordenadas 3 o 05 ’ 45,84 ” S e 59 o 58 ’ 43,69 ”, a partir, de 30 indivíduos de S. inajai. Observou-se que o número de flores por inflorescência varia entre 5.904 - 17.316 para flores estaminadas e 180 - 3.528 para as flores pistiladas. As flores estaminadas apresentam seis estames com um feixe vascular cada; pistilódio trifído e vascularizado. As flores pistiladas apresentam seis estaminódios unidos formando um círculo. O gineceu é sincárpico, tricarpelar, trilocular, um óvulo por lóculo, sin-ascidiado no ovário e plicado acima. A fusão incompleta dos flancos dos carpelos formam três cavidades septais, que vão da base do ovário a base do estígma. Estigma tripartido, apical e séssil, com epiderme composta por células papilosas alongadas, padrão de epiderme que se mantem por todo canal estilar. O ovário apresenta duas regiões meristemáticas, uma adjacente à epiderme externa e outra envolvendo a cavidade seminal. A região meristemática externa origina o mesocarpo fibroso. A região meristemática interna é responsável pelo espessamento do endocarpo, juntamente com as células provenientes de divisões periclinais da epiderme interna do ovário, formando o endocarpo lato sensu de origem mista. A esclerificação do endocarpo inicia-se no fruto com aproximadamente 80 dias, e ocorre centripetamente. O endosperma é do tipo coenocítico multicelular e a formação de parede das células ocorre centrifugamente. O óvulo é anátropo. A semente é paquicalazal e bitegumentada, estes restritos a região da micrópila. O opérculo é composto por células dos tegumentos externo e interno, e por células do obturador, esclerificadas. O zigoto tem sua primeira divisão celular cerca de 30 dias após o início do desenvolvimento do endosperma. O tempo de desenvolvimento do fruto é de aproximadamente 240 dias, quando se inicia a dispersão. O processo de desenvolvimento embrionário dura aproximadamente 220 dias, dividido em 4 estádios: proembrião, embrião globular, cordiforme lateral e torpedo. O embrião é pequeno, linear e derivado da célula terminal do proembrião, proveniente de divisões mitóticas na célula apical. O eixo embrionário está localizado na região proximal em ângulo reto ao maior comprimento do ix embrião. O cotilédone único é formado pelo meristema fundamental, procâmbio e protoderme. O procâmbio provê o eixo embrionário e a região haustorial. A germinação de S. inajai inicia-se em média 101 dias após a semeadura com a formação do botão germinativo. Os eventos morfoanatômicos que se seguiram foram: alongamento do hiperfilo, intumescimento da bainha cotiledonar, emissão da raiz primária e primeiro catafilo, emissão do segundo catafilo e eofilo. O alongamento do eixo embrionário foi observado após a emissão do botão germinativo, durante o processo de alongamento do hiperfilo. A observação da raiz primária em vista desarmada foi possível após o intumescimento da bainha cotiledonar, momento em que os dois catafilos e o eofilo encontravam-se diferenciados na bainha cotiledonar. Foi observado amido no embrião antes da germinação, porém a sua quantidade aumentou nas células parenquimáticas após a formação do botão germinativo. A semente apresentou 30% de lipídios em sua concentração. Transcorre-se 270 dias, da abertura da bráctea peduncular a dispersão do fruto. A abertura da flor pistilada ocorre 20 dias após a abertura da bráctea peduncular, o fruto leva cerca de 240 dias para se formar e o embrião 220 dias

Mechanical Strategies to Increase Nutritional and Sensory Quality of Virgin Olive Oil by Modulating the Endogenous Enzyme Activities

This monograph is a critical review of the biological activities that occur during virgin olive oil (VOO) extraction process. Strategic choices of plant engineering systems and of processing technologies should be made to condition the enzymatic activities, in order to modulate the nutritional and the sensory quality of the product toward the consumer expectations. “Modulation” of the product quality properties has the main aim to predetermine the quantity and the quality of 2 classes of substances: polyphenols and volatile compounds responsible of VOO nutritional and sensory characteristics. In the 1st section, a systematic analysis of the literature has been carried out to investigate the main olive enzymatic activities involved in the complex biotransformation that occurs during the mechanical extraction process. In the 2nd section, a critical and interpretative discussion of the influence of each step of the extraction process on the polyphenols and the volatile compounds has been performed. The effect of the different mechanical devices that are part of the extraction process is analyzed and recommendations, strategies, and possible avenues for future researches are suggested. Practical Application In the field of virgin olive oil industry, time and energy should be spent on developing innovative processing plants and equipment able to better modulate the physical parameters that influence endogenous olive enzyme activities, such as temperature, time, amounts of processing water and oxygen. This review paper can be a useful resource to design and develop innovative equipment by offering an exhaustive analysis of mechanical effects of industrial devices and biological effects of endogenous enzymes on the sensory and nutritional properties of virgin olive oil