Approaches in biotechnological applications of natural polymers

Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento Cientfíico e Tecnológico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de Nvíel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)

Ontogeny of the mucilage ducts of Polygala angulata DC. (Polygalaceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)AGUIAR-DIAS, A. C. A. (Pos-Graduacao em Biologia Vegetal, Universidade Estadual de Campinas, Instituto de Biologia, 13083-970, Campinas, SP, Brazil), CARDOSO-GUSTAVSON, P. (Instituto de Botanica de Sao Paulo, 04301-902, SP, Brazil), Ontogeny of the mucilage ducts of Polygala angulata DC. (Polygalaceae). J. Torrey Bot. Soc. 138: 255-261. 2011.-The present study describes the occurrence of mucilage ducts within Polygalaceae. Polygala angulata DC. is a species from the Brazilian cerrado that possesses secretory ducts in the stem angles of primary growth. First, a schizogeneous process and later, a lytic process both take place in the course of secretory duct formation, characterizing the development of the glands as schizolysigenous. Histochemical tests confirm the mucilage nature of the exudate. The presumable functions of this gland are associated with xeromorphic adaptation of this species to the cerrado environment.1383255261Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Biota/FAPES [03/12595-7]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [04/09728-8]Biota/FAPES [03/12595-7

Stipular extranuptial nectaries new to Polygala: morphology and ontogeny

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Although taxonomic studies indicate that approximately one-third of the genera of Polygalaceae have nodal glands, few anatomical data are available on the structure and ontogeny of these secretory organs. We studied the as yet unknown origin, structure and function of such glands in Polygala laureola. During field observations, we detected glucose in the secretion using Glicofita Plus (R) and visitors were recorded. Vegetative shoot apices and nodal glands were examined using light microscopy and scanning electron microscopy. The presence of glucose in the secretion allowed us to identify these nodal glands as extranuptial nectaries. Secretory cells occupy a medullary position and are surrounded by phloem. Vascular bundles are concentric, and xylem is only observed at the basal region of the nectary. Nectar is released during the daytime through a pore at the top of the nectary. A stipular origin was confirmed by the fact that the procambial strand is connected to the leaf trace, opposite the leaf gap. The occurrence of stipular extranuptial nectaries in a nodal position is new to Polygala. (C) 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 166, 40-50.16614050Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [04/09728-8]FAPESP [03/12595-7