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Identification of Callose Synthases in Stinging Nettle and Analysis Of
International Journal of Molecular Sciences Communication Identification of Callose Synthases in Stinging Nettle and Analysis of Their Expression in Different Tissues Gea Guerriero 1,* , Emilie Piasecki 1, Roberto Berni 2 , Xuan Xu 1, Sylvain Legay 1 and Jean-Francois Hausman 1 1 Environmental Research and Innovation (ERIN) Department, Luxembourg Institute of Science and Technology, 5, rue Bommel, Z.A.E. Robert Steichen, L-4940 Hautcharage, Luxembourg; [email protected] (E.P.); [email protected] (X.X.); [email protected] (S.L.); [email protected] (J.-F.H.) 2 Department of Life Sciences, University of Siena, via P.A. Mattioli 4, I-53100 Siena, Italy; [email protected] * Correspondence: [email protected]; Tel.: +352-275-888-5096; Fax: +352-275-8885 Received: 14 May 2020; Accepted: 27 May 2020; Published: 28 May 2020 Abstract: Callose is an important biopolymer of β-1,3-linked glucose units involved in different phases of plant development, reproduction and response to external stimuli. It is synthesized by glycosyltransferases (GTs) known as callose synthases (CalS) belonging to family 48 in the Carbohydrate-Active enZymes (CAZymes) database. These GTs are anchored to the plasma membrane via transmembrane domains. Several genes encoding CalS have been characterized in higher plants with 12 reported in the model organism Arabidopsis thaliana. Recently, the de novo transcriptome of a fibre-producing clone of stinging nettle (Urtica dioica L.) was published and here it is mined for CalS genes with the aim of identifying members differentially expressed in the core and cortical tissues of the stem. -
A Comparative Study of the Effect of Field Retting Time on the Properties
fibers Article A Comparative Study of the Effect of Field Retting Time on the Properties of Hemp Fibres Harvested at Different Growth Stages Brahim Mazian 1,2,*, Anne Bergeret 1,*, Jean-Charles Benezet 1 and Luc Malhautier 2 1 Centre des Matériaux des Mines d’Alès, IMT Mines Alès, Université de Montpellier, 6 avenue de Clavières, 30319 Alès Cedex, France; [email protected] 2 Laboratoire du Génie de l’Environnement Industriel, IMT Mines Alès, Université de Montpellier, 6 avenue de Clavières, 30319 Alès Cedex, France; [email protected] * Corresponding: [email protected] (B.M.); [email protected] (A.B.) Received: 25 October 2019; Accepted: 5 December 2019; Published: 7 December 2019 Abstract: In this study, the comparison of field retting of hemp fibres harvested at different growth stages (beginning and end of flowering, seed maturity) was studied. Regardless of the harvest period, identical evolution of the fibres’ properties was observed during retting. The main difference is the kinetics of this transformation, which depend on weather conditions and the initial state of the fibres after harvesting. Retting leads to a change in colour of the stems and fibres, an increase of the cellulose fraction and a gradual improvement of the fibres’ thermal stability, in relation with a decrease in the non-cellulosic materials. This process induces fibre bundle separation into elementary fibres. A long period (5 weeks) is required for getting the highest mechanical properties of fibres harvested at the beginning and the end of flowering. However, the retting of fibres harvested at seed maturity has to be performed in a short period (1 week) in order to avoid over-retting treatment. -
Chapter 5: the Shoot System I: the Stem
Chapter 5 The Shoot System I: The Stem THE FUNCTIONS AND ORGANIZATION OF THE SHOOT SYSTEM PRIMARY GROWTH AND STEM ANATOMY Primary Tissues of Dicot Stems Develop from the Primary Meristems The Distribution of the Primary Vascular Bundles Depends on the Position of Leaves Primary Growth Differs in Monocot and Dicot Stems SECONDARY GROWTH AND THE ANATOMY OF WOOD Secondary Xylem and Phloem Develop from Vascular Cambium Wood Is Composed of Secondary Xylem Gymnosperm Wood Differs from Angiosperm Wood Bark Is Composed of Secondary Phloem and Periderm Buds Are Compressed Branches Waiting to Elongate Some Monocot Stems Have Secondary Growth STEM MODIFICATIONS FOR SPECIAL FUNCTIONS THE ECONOMIC VALUE OF WOODY STEMS SUMMARY ECONOMIC BOTANY: How Do You Make A Barrel? 1 KEY CONCEPTS 1. The shoot system is composed of the stem and its lateral appendages: leaves, buds, and flowers. Leaves are arranged in different patterns (phyllotaxis): alternate, opposite, whorled, and spiral. 2. Stems provide support to the leaves, buds, and flowers. They conduct water and nutrients and produce new cells in meristems (shoot apical meristem, primary and secondary meristems). 3. Dicot stems and monocot stems are usually different. Dicot stems tend to have vascular bundles distributed in a ring, whereas in monocot stems they tend to be scattered. 4. Stems are composed of the following: epidermis, cortex and pith, xylem and phloem, and periderm. 5. Secondary xylem is formed by the division of cells in the vascular cambium and is called wood. The bark is composed of all of the tissues outside the vascular cambium, including the periderm (formed from cork cambium) and the secondary phloem. -
Raffia Palm Fibre, Composite, Ortho Unsaturated Polyester, Alkali Treatment
American Journal of Polymer Science 2014, 4(4): 117-121 DOI: 10.5923/j.ajps.20140404.03 The Effect of Alkali Treatment on the Tensile Behaviour and Hardness of Raffia Palm Fibre Reinforced Composites D. C. Anike1,*, T. U. Onuegbu1, I. M. Ogbu2, I. O. Alaekwe1 1Department of Pure and Industrial Chemistry, Nnamdi Azikiwe University Awka, Anambra State, Nigeria 2Department of Chemistry Federal University Ndufu-Alike, Ikwo Ebonyi State, Nigeria Abstract The effects of alkali treatment and fibre loads on the properties of raffia palm fibre polyester composite were studied. Some clean raffia palm fibres were treated with 10% NaOH, and ground. The ground treated and untreated fibres were incorporated into the ortho unsaturated polyester resin. The treated and the untreated fibre composites samples were subjected to tensile tests according to ASTM D638 using instron model 3369. The microhardness test was done by forcing a diamond cone indenter into the surface of the hard specimen, to create an indentation. The significant findings of the results showed that alkali treatment improved the microhardness and extension at break at all fibre loads, better than the untreated fibre composites, with the highest values at 20% (14.40 and 3.47mm for microhardness and extension at break respectively). Tensile strength, tensile strain and modulus of elasticity also improved for alkali treated fibre composites, except in 5% and 20% for tensile strength, 15% for tensile strain, and 15% and 20% for modulus of elasticity, compared to the corresponding fibre loads of untreated fibre composites. Keywords Raffia palm fibre, Composite, Ortho unsaturated polyester, Alkali treatment The main drawbacks of such composites are their water 1. -
A Comprehensive Review on Bast Fibre Retting Process for Optimal Performance in Fibre-Reinforced Polymer Composites
Hindawi Advances in Materials Science and Engineering Volume 2020, Article ID 6074063, 27 pages https://doi.org/10.1155/2020/6074063 Review Article A Comprehensive Review on Bast Fibre Retting Process for Optimal Performance in Fibre-Reinforced Polymer Composites C. H. Lee ,1 A. Khalina ,1 S. H. Lee,1 and Ming Liu2 1Institute of Tropical Forestry and Forest Products, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia 2Material Research and Technology Department, Luxembourg Institute of Science and Technology, 5 Rue Bommel Z.A.E. Robert Steichen, L-4940 Hautcharage, Luxembourg Correspondence should be addressed to C. H. Lee; [email protected] and A. Khalina; [email protected] Received 10 December 2019; Accepted 9 May 2020; Published 13 July 2020 Academic Editor: Charles C. Sorrell Copyright © 2020 C. H. Lee et al. (is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Natural fibres are a gift from nature that we still underutilise. (ey can be classified into several groups, and bast natural fibre reinforcement in polymer composites has the most promising performance, among others. However, numerous factors have reported influences on mechanical properties of the fibre-reinforced composite, including natural fibre retting processes. In this review, bast fibre retting process and the effect of enzymatic retting on the fibre and fibre-reinforced polymer composites have been discussed and reviewed for the latest research studies. All retting methods except chemical and mechanical retting processes are involving secretion of enzymes by bacteria or fungi under controlled (enzymatic retting) or random conditions (water and dew retting). -
The Bark: = Periderm
The Bark: = Periderm The bark is everything outside the vascular cambium. As you can see, there is a lot going on in the bark. The Bark: periderm: phellogen (cork cambium): The phellogen is the region of cell division that forms the periderm tissues. Phellogen development influences bark appearance. The Bark: periderm: phellem (cork): Phellem replaces the epidermis as the tree increases in girth. Photosynthesis can take place in some trees both through the phellem and in fissures. The Bark: periderm: phelloderm: Phelloderm is active parenchyma tissue. Parenchyma cells can be used for storage, photosynthesis, defense, and even cell division! The Bark: phloem: Phloem tissue makes up the inner bark. However, it is vascular tissue formed from the vascular cambium. The Bark: phloem: sieve tube elements: Sieve tube elements actively transport photosynthates down the stem. Conifers have sieve cells instead. The cambium: The cambium is the primary meristem producing radial growth. It forms the phloem & xylem. The Xylem (wood): The xylem includes everything inside the vascular cambium. The Xylem: a growth increment (ring): The rings seen in many trees represent one growth increment. Growth rings provide the texture seen in wood. The Xylem: vessel elements: Hardwood species have vessel elements in addition to trachieds. Notice their location in the growth rings of this tree The Xylem: fibers: Fibers are cells with heavily lignified walls making them stiff. Many fibers in sapwood are alive at maturity and can be used for storage. The Xylem: axial parenchyma: Axial parenchyma is living tissue! Remember that parenchyma cells can be used for storage and cell division. -
Material Choices for Fibre in the Neolithic: an Approach Through the Measurement of Mechanical Properties
Harris, S. , Haigh, S., Handley, A. and Sampson, W. (2017) Material choices for fibre in the Neolithic: an approach through the measurement of mechanical properties. Archaeometry, 59(3), pp. 574-591. (doi:10.1111/arcm.12267) There may be differences between this version and the published version. You are advised to consult the publisher’s version if you wish to cite from it. This is the peer-reviewed version of the following article: Harris, S. , Haigh, S., Handley, A. and Sampson, W. (2017) Material choices for fibre in the Neolithic: an approach through the measurement of mechanical properties. Archaeometry, 59(3), pp. 574-591, which has been published in final form at 10.1111/arcm.12267. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. http://eprints.gla.ac.uk/119815/ Deposited on: 02 June 2016 Enlighten – Research publications by members of the University of Glasgow http://eprints.gla.ac.uk MATERIAL CHOICES FOR FIBRE IN THE NEOLITHIC: AN APPROACH THROUGH THE MEASUREMENT OF MECHANICAL PROPERTIES. Susanna Harris, Corresponding Author (1), Sarah Haigh (2), Adrian Handley (3), William Sampson (4). 1) Archaeology, School of Humanities, University of Glasgow, Lilybank Gardens, Glasgow, G12 8QQ, UK, [email protected] 2) School of Materials, Manchester University UK, [email protected] 3) School of Materials, Manchester University UK 4) School of Materials, Manchester University UK, [email protected] ABSTRACT Studies of the Mesolithic-Neolithic transition in Europe have focused on plants and animals exploited for food. However, the exploitation of plants for fibres underwent a significant change with the addition of domestic flax as a fibre crop. -
Bast Fibre Blends. from Field to Fabric. We're Creating a New Generation Of
Bast Fibre Blends. From field to fabric. We’re creating a new generation of natural fibre textiles. Made from pure new wool blended with harvested nettles, hemp and flax. The natural choice Our vision is to be the natural choice for fabric solutions worldwide – quite literally. So we always look to nature to provide the best answers. Nature teaches us so much in terms of rapid renewability, biodegradability, perfect fit for purpose and, of course, beauty. Camira are pioneering designers and manufacturers of so-called bast fibre fabrics made from innovative blends of pure new wool combined with naturally occurring textile fibres derived from harvested nettles, hemp and flax. Bast fibres are found in the outer part of the stem of the plant, just inside the bark, making them strong, elastic and flexible, so ideal characteristics for spinning into yarn and weaving into fabric. 3 A sting in the tale It all started with Sting: an acronym for a four year project titled “Sustainable Technology in Nettle Growing” and the name of our award winning upholstery fabric. Back in 2005, we teamed up with academic partner De Montfort University in Leicester, UK, and led the way in developing an industry-first fabric made from wool and nettle fibre obtained from the common stinging nettle. The project encompassed research into nettle cultivation on UK farmland; harvesting methods and fibre extraction; blending, spinning, weaving and dyeing; technical performance evaluation and lifecycle assessment. Sting has now matured into the Nettle Collection, a family of three textile patterns, and the entire learning process informed the development of a totally new category of natural bast fibre fabrics. -
Tree Anatomy Stems and Branches
Tree Anatomy Series WSFNR14-13 Nov. 2014 COMPONENTSCOMPONENTS OFOF PERIDERMPERIDERM by Dr. Kim D. Coder, Professor of Tree Biology & Health Care Warnell School of Forestry & Natural Resources, University of Georgia Around tree roots, stems and branches is a complex tissue. This exterior tissue is the environmental face of a tree open to all sorts of site vulgarities. This most exterior of tissue provides trees with a measure of protection from a dry, oxidative, heat and cold extreme, sunlight drenched, injury ridden site. The exterior of a tree is both an ecological super highway and battle ground – comfort and terror. This exterior is unique in its attributes, development, and regeneration. Generically, this tissue surrounding a tree stem, branch and root is loosely called bark. The tissues of a tree, outside or more exterior to the xylem-containing core, are varied and complexly interwoven in a relatively small space. People tend to see and appreciate the volume and physical structure of tree wood and dismiss the remainder of stem, branch and root. In reality, tree life is focused within these more exterior thin tissue sets. Outside of the cambium are tissues which include transport cells, structural support cells, generation cells, and cells positioned to help, protect, and sustain other cells. All of this life is smeared over the circumference of a predominately dead physical structure. Outer Skin Periderm (jargon and antiquated term = bark) is the most external of tree tissues providing protection, water conservation, insulation, and environmental sensing. Periderm is a protective tissue generated over and beyond live conducting and non-conducting cells of the food transport system (phloem). -
Surface Modification of Bast-Based Natural Fibers Through Environment Friendly Methods Tayyaba Fatma
Chapter Surface Modification of Bast-Based Natural Fibers through Environment Friendly Methods Tayyaba Fatma Abstract Nowadays, natural products are extremely preferred among the people. These natural products are produced by environment friendly sources. In case of textiles, bast fibers play significant role in producing natural products that are extracted from the stem of various plant and environment friendly in nature. The bast fibers can also improve the livelihood of the poor farmers who are involved in the cultiva- tion of the plants and extraction and processing of the fibers. Therefore, surface modification of established natural fibers (such as hemp, flax, jute, kenaf, urena, nettle, and ramie) and explored natural fibers are momentous area for doing research. And, these modifications can be done through environment friendly methods such as plasma treatment, and utilization of enzymes, bacteria, and fungi. Keywords: natural fibers, surface modification, environment friendly methods, physical and mechanical properties of fibers 1. Introduction At global level, 58% of synthetic fibers is used in clothing in which 77% polyes- ter, 9% nylon, 6% acrylic, and 7% cellulosic fibers take place. Hence, the utilization of synthetic fibers is higher as compared to natural fibers. The synthetic fibers are generally made from polymers that have been synthetically produced from chemi- cal compounds, which create lot of air, land, and water pollutions. These synthetic fibers are more harmful for health of the human being as well as environment because these cannot easily degrade after its use. To overcome health-related problems and also for environmental safety, people are gradually attracted toward more and more use of natural products in both devel- oped and developing countries. -
Composites from Bast Fibres Page 1 of 22
Composites from bast fibres Page 1 of 22 COMPOSITES FROM BAST FIBRES - PROSPECTS AND POTENTIAL IN THE CHANGING MARKET ENVIRONMENT Rajesh D. Anandjiwala1 and Sunshine Blouw2 ABSTRACT Composite materials reinforced with natural fibres, such as flax, hemp, kenaf and jute, are gaining increasing importance in automotive, aerospace, packaging and other industrial applications due to their lighter weight, competitive specific strength and stiffness, improved energy recovery, carbon dioxide sequestration, ease and flexibility of manufacturing and environmental friendliness besides the benefit of the renewable resources of bast fibres. The market scenario for composite applications is changing due to the introduction of newer bio- degradable polymers, such as PLA synthesized from corn, development of composite making techniques and new stringent environmental laws requiring improved recyclability or biodegradability for industrial applications where stress bearing capacities and micro- mechanical failures dictate serviceability. Bast fibre reinforced composites, made from bio- degradable polymers, will have to compete with conventional composites in terms of their mechanical behaviour. Bio-composites, in which natural fibres such as kenaf, jute, flax, hemp, sisal, corn stalk, bagasse or even grass are embedded in a biodegradable matrix, made as bioplastics from soybean, corn and sugar, have opened-up new possibilities for applications in automotive and building products. Obviously, new approaches to research and development will be required to assess their mechanical properties and also their commercial 1 Ph.D., C.Text. FTI, Business Area Manager – Dry Processing, Centre for Fibre, Textile & Clothing, Manufacturing & Materials Division, CSIR, P.O. Box 1124, Port Elizabeth 6000, South Africa, E-mail: [email protected] and Senior Lecturer, Department of Textile Science, Faculty of Science, University of Port Elizabeth, P.O. -
Retting Process of Some Bast Plant Fibres and Its Effect on Fibre Quality: a Review
PEER-REVIEWED ARTICLE bioresources.com RETTING PROCESS OF SOME BAST PLANT FIBRES AND ITS EFFECT ON FIBRE QUALITY: A REVIEW Paridah Md. Tahir,a Amel B. Ahmed,a Syeed O. A. SaifulAzry,a and Zakiah Ahmed b Retting is the main challenge faced during the processing of bast plants for the production of long fibre. The traditional methods for separating the long bast fibres are by dew and water retting. Both methods require 14 to 28 days to degrade the pectic materials, hemicellulose, and lignin. Even though the fibres produced from water retting can be of high quality, the long duration and polluted water have made this method less attractive. A number of other alternative methods such as mechanical decortication, chemical, heat, and enzymatic treatments have been reported for this purpose with mixed findings. This paper reviews different types of retting processes used for bast plants such as hemp, jute, flax, and kenaf, with an emphasis on kenaf. Amongst the bast fibre crops, kenaf apparently has some advantages such as lower cost of production, higher fibre yields, and greater flexibility as an agricultural resource, over the other bast fibres. The fibres produced from kenaf using chemical retting processes are much cleaner but low in tensile strength. Enzymatic retting has apparent advantages over other retting processes by having significantly shorter retting time and acceptable quality fibres, but it is quite expensive. Keywords: Kenaf; Bast long fibres; Retting; Fibre characteristics; Pectic materials; Enzyme Contact information: a: