DOCSLIB.ORG

Biopolymer Films and Potential Applications to Meat and Poultry Products

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Biopolymer Films and Potential Applications to Meat and Poultry Products Biopolymer Films and Potential Applications to Meat and Poultry Products Paul Dawson, James Acton, & Amod Ogale Clemson University Potential Advantages • Reduced dependence on petroleum sources • Use of U.S. agricultural raw materials • As a food contact layer to carry adjuncts • Biodegradability •Cost?? Definition of Biopolymer Packaging • Packaging produced from renewable, biological material Biopolymers for Packaging from biomass Polysaccharides Proteins Cellulose Casein Starch Whey Gums Gluten Chitosan/Chitin Soy Egg/meat synthesized Polylactate (PLA) Other polyesters microbial Polyhydroxy-alcanoates (PHA) – butyrate (PHB) Ref: Vibeke K Haugaard and Grete Bertelsen, Centre for Advanced Food Studies (LMC) The Royal Veterinary and Agricultural University, Copenhagen, Denmark Biopolymer films-commercial materials Material Supplier Trade name PLA Cargill Dow NatureWorks PLA Hycail Mitsui LACEA Starch Novamont Mater Bi Biotec Bioplast Earth Shell Earth Shell PHB Biomer Biomer Ref: Vibeke K Haugaard and Grete Bertelsen, Centre for Advanced Food Studies (LMC) The Royal Veterinary and Agricultural University, Copenhagen, Denmark Biodegradation •Microbial – Aerobic! compost or sludge – Anaerobic! methane + hydrogen • Animal feed • Chemical Optimal Packaging Requirements Product Shelf Barrier Needs life O2 CO2 H2O light MAP raw 1-2 " " " meat wk Raw meat 1-2 " wk Cooked 1-4 " " " meat wk Cured Meat 1-6 " " " " mo Biopolymer films-meat research • 1949 – Pearce & Lavers – carrageenan • 1952 – Klose et al – gelatin • 1963 – Allen et al – alginates • 1967 – Bauer et al – cellulose • 1971 – Mullen – wheat gluten • 1972 – Turbak – corn zein • 1972 – Turbak – soy protein • 1972 – Baker at al – albumen/soy/wheat protein • 1980’s and 1990’s – numerous (mostly cast films) Biopolymer films- applications • Moisture/oxygen barrier • Physical protection • Oil barrier • Breading adhesion • Texture modifier • Antimicrobial/Antioxidant carrier Coating vs. Film • Coating applied as a fluid • Coating adheres to the food surface • Coating is often consumed with the food Meat coating applications • Coatings reduce moisture loss in raw and cooked meat • Antioxidants added to coatings to preserve cooked meat flavor • Coatings used to reduce moisture loss/oxidation in frozen meat and fish Nisin-coated cellulosic films applied to frankfurters Research by Dr. Kay Cooksey, Clemson University Control 156 IU/mL 10,000 IU/mL 10 8 6 4 2 log CFU / Package / CFU log 0 0 102030405060 Day Biopolymer films- flexible films • Crosslinking required to form flexible film • Proteins and carbohydrates have the ability to crosslink and form a film matrix • Two principal methods of forming – Casting – Thermal compression • Extrusion methods Crosslinking Agents • Formaldeyde • Glutaraldehyde • Cysteine • Transglutaminase • UV radiation • Glyoxal Batch Processing - Compression BEFORE AFTER Biopolymer films- flexible films CAST COMPRESSED zein soy press laminated Continuous Processing Physical properties of films Film type Thickness Tensile Strength Elongation (mil) (MPa) (%) Heat-press soy protein 11.8 5.0 123 Cast wheat gluten 3.98 2.6 276 Cast whey protein/glycerol 4.33 13.9 31 Cast soy protein/glycerol NA 37 4.0 Cast corn zein 3.5 0.4 <1.9 cellophane 14.17 114 20 High density PE 0.98 17.3-34.6 300 Low density PE 0.98 8.6-17.3 500 0.75%chitosan/LDPE 4.48 9.2 60 CAST CORN ZEIN FILM 10 9 8 CONTROL 7 LAURIC ACID 6 5 NISIN 4 3 2 NISIN + LAURIC 1 ListeriaListeria monocytogenes monocytogenes (CFU/ml) (CFU/ml) 0 0 2 4 8 12 24 48 Time of Culture Exposure to Film (Hours) THERMALLY COMPACTED SOY PROTEIN FILM 10 9 CONTROL 8 NISIN 7 6 5 4 LAURIC ACID 3 2 NISIN + LAURIC 1 ListeriaListeria monocytogenes monocytogenes (CFU/ml)(CFU/ml) 0 0 2 4 8 12 24 48 Time of Exposure to Film (Hours) Protein Films Comparison of nisin diffusivity 3.0E-10 2.5E-10 a 2.3E-10 a /s) 2 2.1E-10 a 2.0E-10 1.8E-10 1.5E-10 1.0E-10 b Nisin Diffusivity (cm 5.5E-11 5.0E-11 0.0E+00 C-CZ C-WG HP-CZ HP-WG Film Type Application on bologna L. monocytogenes-inoculated turkey bologna exposed to biocide-impregnated soy films control nisin lauric acid N + L 7 control 6 lauric lauric + nisin cfu/ml 5 nisin 4 0171421 Days Turkey bologna inoculated with L. monocytogenes and packaged with nisin in wheat gluten film Non-nisin Nisin 4 a 3.5 a a,b a 3 a,b,c a,b,c a,b,c a,b,c a,b 2.5 a,b,c a,b,c a,b,c a,b,c 2 b,c 1.5 c,d Log Cfu/g 1 d 0.5 d d 0 0246810 -0.5 Time (weeks) CIE a-value Results for Steaks Allowed to Bloom Prior to Packaging with Antioxidant Films Film Control BHA BHT Rosemary Extract d-tocopherol 18 16 14 12 10 a-value 8 6 4 012345678910 Days Color Differences - Antioxidant Discs within Packaged Steaks BHT Control - no disk BHA Chitosan tested as a coating and film CH OH 2 CH2OH O O O OH OH R Cellulose: R= OH R Chitin : R=NHCOCH3 Chitosan : R=NH2 Chitosan coated onto drumsticks 12 11 a a,b a,b 10 b b 9 weight loss(%) 8 control 91% DE 91% DE + 93% DE 93%DE + P < 0.05 nisin nisin SEM = 0.7 n = 6 Chitosan coated onto drumsticks 4 a 3 b b c c 2 Log CFU/ml 1 control 91% DE 91% DE + 93% DE 93%DE + P < 0.05 nisin nisin SEM = 0.4 n = 6 8% chitosan within LDPE films - steak surface 10 9 8 7 6 0% chitosan 5 4% chitosan 4 8% chitosan delta a* value delta 3 2 1 0 0 1 2 3 4 5 6 7 8 days 8% chitosan within LDPE films - steak surface 7 6 5 4 0% chitosan 3 4% chitosan 2 total plate count plate total 8% chitosan 1 0 0246810 days Future • Coatings will still be developed for specific applications • Biopolymer films will eventually enter the market as cost and functionality get near that of synthetic polymers • Requirements for meat packaging make this one of the most difficult areas for biopolymers to meet.
Load more

Recommended publications
  • A Review on Revolutionary Natural Biopolymer-Based Aerogels for Antibacterial Delivery
    antibiotics Review A Review on Revolutionary Natural Biopolymer-Based Aerogels for Antibacterial Delivery Esam Bashir Yahya 1 , Fauziah Jummaat 2,*, A. A. Amirul 3,* , A. S. Adnan 2, N. G. Olaiya 1 , C. K. Abdullah 1 , Samsul Rizal 4, M. K. Mohamad Haafiz 1 and H. P. S. Abdul Khalil 1,* 1 School of Industrial Technology, Universiti Sains Malaysia, Penang 11800, Malaysia; [email protected] (E.B.Y.); [email protected] (N.G.O.); [email protected] (C.K.A.); mhaafi[email protected] (M.K.M.H.) 2 Management Science University Medical Centre, University Drive, Off Persiaran Olahraga, Section 13, Shah Alam, Selangor 40100, Malaysia; [email protected] 3 School of Biological Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia 4 Department of Mechanical Engineering, Universitas Syiah Kuala, Banda Aceh 23111, Indonesia; [email protected] * Correspondence: [email protected] (F.J.); [email protected] (A.A.A.); [email protected] (H.P.S.A.K.) Received: 10 September 2020; Accepted: 27 September 2020; Published: 28 September 2020 Abstract: A biopolymer-based aerogel has been developed to become one of the most potentially utilized materials in different biomedical applications. The biopolymer-based aerogel has unique physical, chemical, and mechanical properties and these properties are used in tissue engineering, biosensing, diagnostic, medical implant and drug delivery applications. Biocompatible and non-toxic biopolymers such as chitosan, cellulose and alginates have been used to deliver antibiotics, plants extract, essential oils and metallic nanoparticles. Antibacterial aerogels have been used in superficial and chronic wound healing as dressing sheets. This review critically analyses the utilization of biopolymer-based aerogels in antibacterial delivery.
    [Show full text]
  • A Comparative Review of Natural and Synthetic Biopolymer Composite Scaffolds
    polymers Review A Comparative Review of Natural and Synthetic Biopolymer Composite Scaffolds M. Sai Bhargava Reddy 1 , Deepalekshmi Ponnamma 2 , Rajan Choudhary 3,4,5 and Kishor Kumar Sadasivuni 2,* 1 Center for Nanoscience and Technology, Institute of Science and Technology, Jawaharlal Nehru Technological University, Hyderabad 500085, India; [email protected] 2 Center for Advanced Materials, Qatar University, Doha P.O. Box 2713, Qatar; [email protected] 3 Rudolfs Cimdins Riga Biomaterials Innovations and Development Centre of RTU, Faculty of Materials Science and Applied Chemistry, Institute of General Chemical Engineering, Riga Technical University, Pulka St 3, LV-1007 Riga, Latvia; [email protected] 4 Baltic Biomaterials Centre of Excellence, Headquarters at Riga Technical University, LV-1007 Riga, Latvia 5 Center for Composite Materials, National University of Science and Technology “MISiS”, 119049 Moscow, Russia * Correspondence: [email protected] Abstract: Tissue engineering (TE) and regenerative medicine integrate information and technology from various fields to restore/replace tissues and damaged organs for medical treatments. To achieve this, scaffolds act as delivery vectors or as cellular systems for drugs and cells; thereby, cellular material is able to colonize host cells sufficiently to meet up the requirements of regeneration and repair. This process is multi-stage and requires the development of various components to create the desired neo-tissue or organ. In several current TE strategies, biomaterials are essential compo- nents. While several polymers are established for their use as biomaterials, careful consideration of the cellular environment and interactions needed is required in selecting a polymer for a given Citation: Reddy, M.S.B.; Ponnamma, application.
    [Show full text]
  • Biopolymer Films and Potential Applications to Meat and Poultry Products
    FRESH MEAT/PACKAGING II Biopolymer Films and Potential Applications to Meat and Poultry Products Paul L. Dawson, James C. Acton* and Amod A. Ogale Introduction developing bio-based packaging in Europe and some U.S. companies are utilizing modified starch materials. Commer- Large amounts of packaging waste are discarded into the cial raw materials include polylactate produced by Cargill U.S. municipal waste system each year. Over 23 million Dow (trade name NatureWorks PLA) and by Mitsui under tons of plastic packaging waste was generated in 1998 (EPA the trade name LACEA. Other starch-based raw packaging 1999). To reduce the amount of synthetic polymer waste, a materials include Novamont (Mater Bi), Biotec (Bioplast), considerable amount of research has been devoted to the and Earth (Earth Shell). These materials require chemical production of bio-based polymer films derived from natural modification of native starch materials and have been tested sources. The use of plant material to form films is an active as molded containers (Salvage, 2001). Much of the re- research topic (Jane et al., 1996). As new applications for search on biopolymer films has involved the production of such materials are still emerging, characterization of renew- films from the method of solvent casting. In contrast, ther- able biopolymers is very important if these materials are to mal processing methods such as compression molding and be used for packaging applications. extrusion have received limited attention. Jane and Wang A question concerning the use of biopolymers as packag- (1996) and Huang et al. (1995) reported on an extru- ing materials is why should these materials be used instead sion/molding technique, whereas Paetau et al.
    [Show full text]
  • Sergio Rotstein (Pfizer)
    What About the Big Guys? The emerging HELM standard for macromolecular representation and the Pistoia Alliance Sergio H. Rotstein – Pfizer Incorporated [email protected] Introduction • Pfizer Goal: “Top-tier biotherapeutics company by 2015” –But informatics infrastructure was inadequate • Biomolecules Team Goal: Remediate infrastructure to enable biomolecule –Registration –Visualization –Analysis and design –Workflows • Many companies facing a similar challenge • Pistoia HELM Goal: Facilitate the public release of HELM, providing a standard for data exchange and reducing need for other companies to develop their own equivalent systems 2 What is a “Biomolecule”? For our purposes, anything that is not a small molecule is ASOs a biomolecule siRNAs Peptides Goal • Eliminate biomolecule Therapeutic Antibodies Proteins penalty • Make these entities first- class citizens of the Informatics tool portfolio ADCs Vaccines 3 So what’s the problem? G A Small Molecule Tools P Sequence-Based Tools HN O Small O N O Sequences Molecules Biomolecules 4 “Fit-for-Purpose” Structure Representation We need to enable the representation, manipulation and visualization of each molecule type in a way that is appropriate for its size and complexity 5 Fit for Purpose: “Monomer” Level • While you could draw out an oligonucleotide like this: • The representation is likely more intuitive / practical: 6 Fit for Purpose: Sequence Level • But even the monomer level representation would not scale well to proteins with hundreds of amino acids. Larger molecules require a more sequence-oriented representation: 7 Fit for Purpose: Component Level • For multi-component structures such as antibody drug conjugates, component level representations are required to enable each component to dealt with separately.
    [Show full text]
  • A Resonant Capacitive Test Structure for Biomolecule Sensing
    A RESONANT CAPACITIVE TEST STRUCTURE FOR BIOMOLECULE SENSING Thesis Submitted to The School of Engineering of the UNIVERSITY OF DAYTON In Partial Fulfillment of the Requirements for The Degree of Master of Science in Electrical Engineering By Danielle Nichole Bane UNIVERSITY OF DAYTON Dayton, Ohio August, 2015 A RESONANT CAPACITIVE TEST STRUCTURE FOR BIOMOLECULE SENSING Name: Bane, Danielle Nichole APPROVED BY: Guru Subramanyam, Ph.D. Karolyn M. Hansen, Ph.D. Advisor Committee Chairman Advisor Committee Member Professor and Chair, Department of Professor, Department of Biology Electrical and Computer Engineering Partha Banerjee, Ph.D Committee Member Professor, Department of Electrical and Computer Engineering John G. Weber, Ph.D. Eddy M. Rojas, Ph.D., M.A., P.E. Associate Dean Dean School of Engineering School of Engineering ii c Copyright by Danielle Nichole Bane All rights reserved 2015 ABSTRACT A RESONANT CAPACITIVE TEST STRUCTURE FOR BIOMOLECULE SENSING Name: Bane, Danielle Nichole University of Dayton Advisors: Dr. Guru Subramanyam and Dr. Karolyn M. Hansen Detection of biomolecules in aqueous or vapor phase is a valuable metric in the assessment of health and human performance. For this purpose, resonant capacitive sensors are designed and fab- ricated. The sensor platform used is a resonant test structure (RTS) with a molecular recognition element (MRE) functionalized guanine dielectric layer used as the sensing layer. The sensors are designed such that the selective binding of the biomarkers of interest with the MREs is expected to cause a shift in the test structure’s resonant frequency, amplitude, and phase thereby indicating the biomarker’s presence. This thesis covers several aspects of the design and development of these biosensors.
    [Show full text]
  • Biopolymer Production by Bacterial Species Using Glycerol, a Byproduct of Biodiesel
    International Journal of Scientific and Research Publications, Volume 3, Issue 8, August 2013 1 ISSN 2250-3153 Biopolymer production by Bacterial Species using Glycerol, a byproduct of biodiesel S.Sathianachiyar*, Aruna Devaraj** *Research Scholar, Natural Resource Management Centre, Periyakulam,Theni. Tamil Nadu **Director Natural Resource Management Centre, Periyakulam, Theni Tamil Nadu Abstract- Biopolymer producing bacterial species (Bacillus Azotobacter vinelandii, Bacillus subtilis, Haemophilus influenzae and Pseudomonas )were isolated from rhizosphere soil of and Escherichia coli and also in eukaryotic membranes like in Jatropha curcas by using standard morphological, cultural and mitochondria and microsomes as complexes of calcium ions biochemical characteristics.PHB production by bacterial sps (Ca2+) and polyphosphates in a ratio of 2 : 1 : 2 (Reusch,1992). were screened by Sudan black B staining method. The main aim of the present study to production of biopolymers using crude The production of biodiesel generates significant glycerol is a byproduct of biodiesel, act as a sole carbon source quantities of co-product stream rich in glycerol. New uses for for PHB producing microorganisms, under the limitation of glycerol have been the subject of much research to alleviate a nitrogen and phosphate . Ammonium molybdate and ammonium market glut of this commodity and to leverage the economics of sulphate were used in nitrogen deficient medium instead of biodiesel production. One potential use of glycerol is in industrial ammonium chloride. Maximum biopolymer production were fermentation where it can be employed as a substrate for noted in Bacillus spp13.3 gm/100ml.Pseudomonas spp yielded microbial growth and the biosynthesis of microbial products. The 11.2 gm/100 ml.
    [Show full text]
  • Biomolecular Materials. Report of the January 13-15, 2002 Workshop
    Cover Illustrations (from top): Molecular graphics representation looking into the channel of the a hemolysin pore. Song!et al., 1996 (Figure 24). Complexation of F-actin and cationic lipids leads to the hierarchical self-assembly of a network of tubules; shown here in cross-section. Wong 2000 (Figure 9). Depiction of an array of hybrid nanodevices powered by F1-ATPase. Soong et al., 2000 (Figure 1). Electronmicrograph, after fixation, of neuron from the A cluster of the pedal ganglia in L. stagnalis immobilized within a picket fence of polyimide after 3 days in culture on silicon chip. (Scale bar = 20!mm.). Zeck and Fromherz 2001 (Figure 16). Biomolecular Materials Report of the January 13-15, 2002 Workshop Supported by the Basic Energy Sciences Advisory Committee U.S. Department of Energy Co-Chairs: Mark D. Alper Materials Sciences Division Lawrence Berkeley National Laboratory and Department of Molecular and Cell Biology University of California at Berkeley Berkeley, CA 94720 Samuel I. Stupp Department of Materials Science and Engineering Department of Chemistry Feinberg School of Medicine Northwestern University Evanston, IL 60208 This work was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under contract DE-AC03-76SF00098 This report is dedicated to the memory of Iran L. Thomas, Deputy Director of the Department of Energy Office of Basic Energy Sciences and Director of the Division of Materials Sciences and Engineering until his death in February, 2003. Iran was among the first to recognize the potential impact of the biological sciences on the physical sciences, organizing workshops and initiating programs in that area as early as 1988.
    [Show full text]
  • Batch Cultivation Model for Biopolymer Production, Chem
    C. E. Torres-Cerna et al., Batch Cultivation Model for Biopolymer Production, Chem. Biochem. Eng. Q., 31 (1) 89–99 (2017) 89 Batch Cultivation Model for Biopolymer Production This work is licensed under a a,◊ a,◊,* b Creative Commons Attribution 4.0 C. E. Torres-Cerna, A. Y. Alanis, I. Poblete-Castro, International License and E. A. Hernandez-Vargasc,d,* aCUCEI, Universidad de Guadalajara, Blvd. Marcelino Garcia Barragan 1421, Col. Olimpica, Guadalajara, Jalisco, México, C. P. 44430 bUniversidad Andrés Bello, Faculty of Biological Sciences, Center for Bioinformatics and Integrative Biology, Biosystems Engineering Laboratory, 8340176 Santiago, Chile cSystems Medicine of Infectious Diseases, Helmholtz Centre doi: 10.15255/CABEQ.2016.952 for Infection Research, Inhoffenstr. 7, 38124 Braunschweig, Germany Original scientific paper dFrankfurt Institute for Advanced Studies (FIAS), Received: July 19, 2016 Ruth-Moufang-Str. 1, 60438 Frankfurt am Main, Germany Accepted: March 7, 2017 This paper presents a mathematical model to evaluate the kinetics of two different Pseudomonas putida strains, wild and mutant-type for the microbial production of poly- hydroxyalkanoates (PHAs). Model parameters were estimated to represent adequately experimental data from the batch reactor using the differential evolution algorithm. Based on the mathematical model with the best-fit parameter values, simulations suggested that the high production of PHA by the mutant strain can be attributed not only to the higher production of PHA but also to a reduction in the consumption rate of the substrates of approximately 66 %. Remarkably, the cell growth rate value is higher for the wild type than the mutant type, suggesting that the PHA increase is not only to an increase in the production rate but also to the metabolism of the cells.
    [Show full text]
  • Production of Biopolymer from Bacteria - a Review
    Environmental and Earth Sciences Research Journal Vol. 8, No. 2, June, 2021, pp. 91-96 Journal homepage: http://iieta.org/journals/eesrj Production of Biopolymer from Bacteria - A Review Ranganadha Reddy Aluru1*, Sravani Koyi1, Sanjana Nalluru1, Chandrasekhar Chanda2 1 Department of Biotechnology, VFSTR, Vadlamudi, Guntur 522213, Andhra Pradesh, India 2 Department of Biotechnology, Koneru Lakshmaiah Education Foundation, Guntur 522502, Andhra Pradesh, India Corresponding Author Email: [email protected] https://doi.org/10.18280/eesrj.080205 ABSTRACT Received: 10 March 2021 Polyhydroxyalkanoates (PHA) producers have been found in a variety of ecological Accepted: 29 May 2021 niche’s that are naturally or unintentionally exposed to high organic matter or growth limiting substances such as dairy wastes, hydrocarbon contaminated sites, pulp and paper Keywords: mill wastes, agricultural wastes, activated sludges of treatment plants, rhizosphere, and polyhydroxyalkanoates, bacteria, biopolymer, industrial effluents. Few of them also create extracellular byproducts such as bioplastic, polyhydroxubutyrate rhamnolipids, extracellular polymeric compounds, and biohydrogen gas. These microbes can use waste materials of various origin as substrates while producing valuable bioproducts such as PHB. As a result, these microbes are industrially important candidates for production; Implementation of an integrated system to separate their by- products (intracellular and extracellular) could be an economical method. In this study, we reviewed several microorganisms that live in diverse environmental situations and are stimulated to collect carbon as polyhydroxyalkanoates granules, as well as variables that influence their production and composition. Ultimately, the current cost of bioplastic manufacture from stored PHA granules can be decreased by investigating capabilities such as dual generation of microorganisms and utilization of wastes as renewable substrate under optimal growth conditions in either a batch or continuous process.
    [Show full text]
  • Biopolymer Networks and Cellular Mechanosensing
    University of Pennsylvania ScholarlyCommons Institute for Medicine and Engineering Papers Institute for Medicine and Engineering June 2004 Biopolymer Networks and Cellular Mechanosensing Penelope Georges University of Pennsylvania Oliver Wagner University of Pennsylvania Tony Yeung University of Pennsylvania Paul Janmey University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/ime_papers Georges, Penelope; Wagner, Oliver; Yeung, Tony; and Janmey, Paul, "Biopolymer Networks and Cellular Mechanosensing" (2004). Institute for Medicine and Engineering Papers. 20. https://repository.upenn.edu/ime_papers/20 Reprinted from Gravitational and Space Biology, Volume 17, Issue 2, June 2004, pages 45-50. Publisher URL: http://gravitationalandspacebiology.org/index.php/journal This paper is posted at ScholarlyCommons. https://repository.upenn.edu/ime_papers/20 For more information, please contact [email protected]. Biopolymer Networks and Cellular Mechanosensing Abstract Cells and tissues are mechanical as well as biochemical machines, and cellular response to mechanical cues can have as large an influence on structure and function as chemical signals. The mechanical properties of cells are largely determined by networks of semiflexible polymers forming the cytoskeleton, which has viscoelastic properties that differ in important ways from the viscoelasticity of common synthetic materials. Two such features are the high resistance to deformation achieved by a remarkably low volume fraction of protein, and the increase in stiffness that occurs when the cytoskeletal network is deformed. The actin filaments, microtubules and intermediate filaments that comprise the cytoskeleton of most cell types are linear polymers with some important similarities but also some fundamental differences. The stiffness of the individual polymer types is vastly different, with persistence lengths ranging from 1 mm for the 24 nm diameter microtubules to a few 100 nm for the 10-14 nm diameter intermediate filaments.
    [Show full text]
  • Bioplastic and Biopolymer Production - Ian W
    BIOTECHNOLOGY - Vol. V - Bioplastic and Biopolymer Production - Ian W. Sutherland BIOPLASTIC AND BIOPOLYMER PRODUCTION Ian W. Sutherland, Institute of Cell and Molecular Biology, University of Edinburgh, Edinburgh, United Kingdom Keywords: ABC-transporters, Archae, Bacterial alginate, Bioplastics, Biopolymers, Biosynthesis, Carbon and energy reserves,Cellulose, Curdlan, Dextrans, Dextransucrase, β-D-Glucans, α-D-Glucans, Exopolysaccharides (EPS), Fructans, Gellan, Heparinm, Heteropolysaccharides , Hyaluronic Acid, Levan, levansucrase, Negative regulation, Polyhydroxyalkanoic acids (PHAs), β-hydroxybutyric acid (PHB), Polysaccharides, Positive regulation, Regulation of synthesis, Scleroglucan, lucan, Xanthan Contents 1. Bioplastics 1.1. Introduction 1.2. Occurrence & Composition 1.3. Biosynthesis 1.4. Products 1.5. Production and Recovery 2. Biopolymers (Polysaccharides) 2.1. Introduction 2.2. Occurrence and Composition 2.3. Polysaccharide biosynthesis 2.3.1. Biosynthetic mechanisms 2.3.2. Genetics and Regulation of Exopolysaccharides Synthesis 2.4. Commercial Products 2.4.1. β-D-Glucans 2.4.2. α-D-Glucans 2.4.3. Bacterial Alginates 2.4.4. Gellan and Related Polymers 2.4.5. Hyaluronic Acid and Heparin 2.4.6. Succinoglycan and Galactoglucans 2.4.7. XanthanUNESCO – EOLSS 2.5. Production of exopolysaccharides 3. Future Developments 3.1. Bioplastics SAMPLE CHAPTERS 3.2. Biopolymers Glossary Bibliography Biographical Sketch Summary Micro-organisms provide a source of bioplastics and biopolymers (polysaccharides) from renewable sources. Although currently considerably more expensive than plastic ©Encyclopedia of Life Support Systems (EOLSS) BIOTECHNOLOGY - Vol. V - Bioplastic and Biopolymer Production - Ian W. Sutherland derived from petrochemicals, bacteria have proved capable of yielding bioplastics with comparable properties. They have the additional advantage of being biodegradable. The processes, which have been developed for their production, have been optimised and a range of products obtained.
    [Show full text]
  • Amino Acids, Peptides, and Proteins. Monomer Unit: Α-Amino Acids H NH2 R = Sidechain R CO2H
    Chapter 27: Amino Acids, Peptides, and Proteins. monomer unit: α-amino acids H NH2 R = sidechain R CO2H !- Amino Acid Biopolymer: the monomeric amino acids are linked through an amide bond (the carboxylic acids of one AA with the α-amino group of a second) R R1 R 1 H + 2 - H2O N CO2 H3N CO2 H3N H3N CO2 C-terminus O R N-terminus 2 O R O R O R O H 2 H 4 H 6 H N N N N N N N N H H H H R1 O R3 O R5 O R7 Peptide or protein (polypeptide) peptide (< 50 amino acids) protein (> 50 amino acids) 307 27.1: Classification of Amino Acids. AA’s are classified according to the location of the amino group. H H H H H H H2N C CO2H H2N C C CO2H H2N C C C CO2H H H H H H H !-amino acid "-amino acid #-amino acid (2-amino carboxylic acid) (3-amino carboxylic acid) (4-amino carboxylic acid) There are 20 genetically encoded α-amino acids found in peptides and proteins 19 are primary amines, 1 (proline) is a secondary amine 19 are “chiral”, 1 (glycine) is achiral; the natural configuration of the α-carbon is L. CHO CHO CO2H CO2H H OH HO H H2N H H2N H CH OH CH OH 2 2 CH3 R D-glyceraldehyde L-glyceraldehyde L-alanine CHO CHO CO2H CO2H HO H H OH H2N H H2N H H OH HO H H OH H3C H CH2OH CH2OH CH3 CH2CH3 308 D-erythrose L-erythrose L-theronine L-isoleucine (2S,3R) (2S,3S) 157 α-Amino acids are classified by the properties of their sidechains.
    [Show full text]