Natural Products Chemistry

Biomedical and Pharmaceutical Phytochemistry

Tatiana G. Volova, Debarshi Kar Mahapatra, Sonia Khanna, A. K. Haghi, Tatiana G. Volova, Debarshi Kar Mahapatra, Sonia Khanna, A. K. Haghi

• Publisher: Apple Academic Press
• Year: 2020
• ISBN:
  9781000751550
• Edition: 1
• Topic: Sciences biologiques
• Subtopic: Science générale

Natural Products Chemistry: Biomedical and Pharmaceutical Phytochemistry focuses on the development of biochemical, biomedical and their applications. It highlights the importance of accomplishing an integration of engineering with biology and medicine to understand and manage the scientific, industrial, and clinical aspects. It also explains both the basic science and the applications of biotechnology-derived pharmaceuticals, with special emphasis on their clinical use.

The biological background provided enables readers to comprehend the major problems in biochemical engineering and formulate effective solutions. This title also expands upon current concepts with the latest research and applications, providing both the breadth and depth researchers need. The book also introduces the topic of natural products chemistry with an overview of key concepts.

This book is aimed at professionals from industry, academicians engaged in chemical science or natural product chemistry research, and graduate-level students.

CHAPTER 1
Bacterial Nanocellulose: Synthesis, Properties, Hybrids with Nano-Silver for Tissue Engineering

E. I. SHISHATSKAYA^1,2, S. V. PRUDNIKOVA¹, A. A. SHUMILIVA¹, and T. G. VOLOVA^1,2*

¹ Siberian Federal University, 79 Svobodnyi Av., Krasnoyarsk 660041, Russia

² Institute of Biophysics SB RAS, Federal Research Center “Krasnoyarsk Science Center SB RAS” 50/50 Akademgorodok, Krasnoyarsk 660036, Russia

^* Corresponding author. E-mail: [email protected]

ABSTRACT

A strain of acetic acid bacteria, Komagataeibacter xylinus B-12068, was studied as a source for bacterial cellulose (BC) production. The effects of cultivation conditions (carbon sources, temperature, and pH) on BC production and properties were studied in surface and submerged cultures. Glucose was found to be the best substrate for BC production among the sugars tested; ethanol concentration of 3% (w/v) enhanced the productivity of BC. The highest BC yield (up to 17.0–23.2 g/L) was obtained under surface static cultivation conditions, in the modified Hestrin–Schramm medium supplemented with ethanol, at pH 3.9, after seven days of cultivation in the thinnest layer of the medium. C/N elemental analysis, emission spectrometry, scanning electron microscopy (SEM), differential thermal analysis (DTA), and X-ray were used to investigate the structural, physical, and mechanical properties of the BC produced under different conditions. The MTT assay and SEM showed that the native cellulose membrane did not cause cytotoxicity upon direct contact with NIH 3T3 mouse fibroblast cells and was highly biocompatible.

BC composites synthesized in the culture of the strain of acetic acid bacterium K. xylinus with silver nanoparticles, BC/AgNPs, were produced hydrothermally, under different AgNO₃ concentrations (0.0001, 0.001, and 0.01 M) in the reaction medium. The presence of silver in the BC/AgNP composites was confirmed by the elemental analysis conducted using scanning electron microscopy with a system of X-ray spectral analysis: silver content in the composites increased from 0.044 to 0.37 mg/cm². The surface structure, properties, and physicochemical characteristics of composites were investigated. The disk-diffusion method and the shake-flask culture method used in this study showed that all experimental BC/AgNP composites had pronounced antibacterial activity against Escherichia coli, Pseudomonas eruginosa, Klebsiella pneumoniae, and Staphylococcus aureus. No potential cytotoxicity was detected in any of the BC/AgNP composites in the NIH 3T3 mouse fibroblast cell culture, in contrast to the BC/antibiotic composites. These results suggest that BC composites constructed in the present study hold promise as dressings for managing wounds, including contaminated ones.

Hybrid wound dressings have been constructed using two biomaterials: BC and copolymer of 3-hydroxybutyric and 4-hydroxybutyric acids (P(3HB-co-4HB))—a biodegradable polymer. Some of the experimental membranes were loaded with drugs promoting wound healing and epidermal cells differentiated from multipotent adipose-derived mesenchymal stem cells. A study has been carried out to investigate the structural, physical and mechanical properties of the membranes. The in vitro study showed that the most effective scaffolds for growing fibroblasts were composite BC/P(3HB-co-4HB) films loaded with actovegin. Two types of experimental biotechnological wound dressings—BC/P(3HB/4HB)/actovegin and BC/P(3HB-co-4HB)/fibroblasts—were tested in vivo, on laboratory animals with model third-degree skin burns. Wound planimetry; histological examination; and biochemical and molecular methods of detecting factors of angiogenesis, inflammation, type-I collagen, keratin 10, and keratin 14 were used to monitor wound healing. Experimental wound dressings promoted healing more effectively than VoskoPran—a commercial wound dressing.

1.1 INTRODUCTION

Cellulose is extracellular polysaccharide synthesized by higher plants, lower phototrophs, and prokaryotes belonging to various taxa (Ullah et al., 2016). Although bacterial cellulose (BC) is produced in laboratories on a small scale for research, there are some commercial outlets for BC. In addition, traditional nata de coco (Iguchi et al., 2000), Fzmb GmbH, a German company, is considered one of the largest producers of BC for cosmetics and biomedical applications (Keshk et al., 2014a). In addition, Xylos Co., USA, is a producer of Prima CelTM, a type of BC used for wound dressing. Other brands of BC include Gengiplex^® and Biofill^® (Keshk et al., 2014a), which are used as a physical barrier for tissue regeneration. BC is also produced and used by many food industries in Asian countries (Budhiono et al., 1999; Ng and Shyu, 2004). Sony Corporation, Japan, in association with Ajinomoto, Japan, and other firms fabricated the first BC-based diaphragm for an audio speaker. Ajinomoto, Japan, also sells wet BC (Chawla et al., 2009; Czaja et al., 2006).

A promising material for biomedical application is BC—a biopolymer synthesized by microorganisms. The chemical structure of BC is similar to that of plant-derived cellulose, but it has unique physical, mechanical, and chemical properties, such as high strength, elasticity, gas permeability, good water-holding capacity, porosity, etc. This material shows high biocompatibility, without being cytotoxic or causing any allergic reactions. Studies on BC suggest that this natural polymer can be useful for cellular and tissue engineering as a material for constructing scaffolds and for reconstructive surgery as a material for skin defect reconstruction and as a matrix for drug delivery (Ma et al., 2010; Saska et al., 2011). Cellulose is used in a variety of applications in food and paper industries, medicine, and pharmaceutics. Gel pellicles of BC have an ordered structure: they are three-dimensional (3D) networks consisting of ribbon-like randomly oriented cellulose microfibrils. This structural arrangement of BC and its high compatibility with biological tissues make it an attractive material for reconstructive surgery; skin tissue repair; target tissue regeneration in dentistry, general surgery, and maxillofacial surgery; and cell and tissue engineering—as a carrier for drugs.

The physical and mechanical properties of BC can be enhanced by preparing BC composites with various materials: chitosan (Lin et al., 2013), collagen (Culebras et al., 2015), sodium alginate, gelatin, and polyethylene glycol (Shah et al., 2013). BC is not inherently antibacterial, but BC composites with chitosan and alginate inhibit the growth of pathogenic microorganisms such as Escherichia coli, Candida albicans, and Staphylococcus aureus (Lin et al., 2013; Kwak et al., 2015; Chang et al., 2016). Therefore, BC composite films can be considered for treating infected skin wounds. Owing to its 3D and porous structure, BC can be hybridized with metallic silver particles to produce an antibacterial and wound-healing formulation. Metallic silver and compounds thereof have a strong bactericidal effect, inhibiting the growth of a wide range of pathogenic microorganisms. Silver ions react with cell membrane protein thiol groups, affecting bacterial respiration and transportation of substances through the cell membrane (Percival et al., 2005). Several authors have described different techniques for preparing BC composites with silver nanoparticles (BC/AgNPs) and demonstrated thir high antibacterial activities (Sureshkumar et al., 2010; Feng et al., 2014; Wen et al., 2015; Wu et al., 2014; Sadanand et al., 2017). Another approach to imparting antibacterial activity to BC against pathogenic microflora is to prepare BC composites with antibiotics. While this approach has been described in a few studies (Shao et al., 2016; Wijaya et al., 2017), it remains poorly developed.

The purpose of the present study is to investigate the strain Komagataeibacter xylinus B-12068 as a new producer of the influence of culture conditions on the structure and properties of BC; to prepare BC/AgNPs and to investigate their antibacterial activity; to construct and investigate composites based on BC and polyhydroxyalkanoate (PHA) as biotechno-logical wound dressings; to evaluate their efficacy in managing model skin burns in experiments with laboratory animals.

1.2 MATERIALS AND METHODS

1.2.1 CHARACTERIZATION OF THE BACTERIAL STRAIN

A new bacterial strain K. xylinus B-12068 was isolated from the fermented tea (kombucha) Medusomyces gisevii J. Lindauon Hestrin–Schramm (HS) medium (Hestrin and Schramm, 1954). The strain was identified based on its morphological, biochemical, genetic, and growth parameters. The strain K. xylinus was deposited in the Russian National Collection of Industrial Microorganisms (VKPM) with registration number VKPM B-12068. The morphology of bacterial cells was studied in Gram-stained preparations. The phenotypic properties were studied using conventional microbiological techniques. The morphology of vegetative cells; spore formation; motility; reaction to Gram staining; requirement of growth factors; the presence of nitrate reductase; catalase, oxidase, amylase, and proteinase activities; antibiotic sensitivity; and NaCl sensitivity were determined. Growth on carbon sources such as glucose, sucrose, maltose, galactose, and mannitol was tested in the basal HS medium supplemented with 2% (w/v) of each carbohydrate. The strain produced BC on the surface and in submerged cultures (Prudnikova et al., 2014).

1.2.2 CULTIVATION OF THE STRAIN AND PRODUCTION OF BACTERIAL CELLULOSE

The collection culture of K. xylinus B-12068 was maintained on...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• About the Editors
• Contents
• Contributors
• Abbreviations
• Preface
• 1. Bacterial Nanocellulose: Synthesis, Properties, Hybrids with Nano-Silver for Tissue Engineering
• 2. Applications of Nanotechnology in Diverse Fields of Supramolecules, Green Chemistry, and Biomedical Chemistry: A Very Comprehensive Review
• 3. Biosynthesis and Therapeutic Potential of Silver Nanoparticles
• 4. Pomegranate Bacterial Blight: Abutilon indicum, Prosopis juliflora, and Acacia arabica as Antibacterial Agents for Xanthomonas axonopodis pv. punicae
• 5. Biocontaminants in Occupational Perspectives: Basic Concepts and Methods
• 6. General and Chemical Perspectives and Studies on Tannins as Natural Phenolic Compounds for Some Ecoefficient Applications
• 7. Bryophytes: Natural Biomonitors
• 8. Applied Techniques for Extraction, Purification, and Characterization of Medicinal Plants Active Compounds
• 9. Panoramic View of Biological Barricades and Their Influence on Polysaccharide Nanoparticle Transport: An Updated Status in Cancer
• 10. Selective Targeting of Human Colon Cancer HCT116 Cells by Phytomediated Silver Nanoparticles
• 11. Promising Anticancer Potentials of Natural Chalcones as Inhibitors of Angiogenesis
• 12. Direct Electrochemical Oxidation of Blood
• Index