150 research outputs found

    Natural quinone dyes : a review on structure, extraction techniques, analysis and application potential

    Get PDF
    Synthetic dyes are by far the most widely applied colourants in industry. However, environmental and sustainability considerations have led to an increasing efforts to substitute them with safer and more sustainable equivalents. One promising class of alternatives is the natural quinones; these are class of cyclic organic compounds characterized by a saturated (C6) ring that contains two oxygen atoms that are bonded to carbonyls and have sufficient conjugation to show color. Therefore, this study looks at the potential of isolating and applying quinone dye molecules from a sustainable source as a possible replacement for synthetic dyes. It presents an in-depth description of the three main classes of quinoid compounds in terms of their structure, occurrence biogenesis and toxicology. Extraction and purification strategies, as well as analytical methods, are then discussed. Finally, current dyeing applications are summarised. The literature review shows that natural quinone dye compounds are ubiquitous, albeit in moderate quantities, but all have a possibility of enhanced production. They also display better dyeability, stability, brightness and fastness compared to other alternative natural dyes, such as anthocyanins and carotenoids. Furthermore, they are safer for the environment than are many synthetic counterparts. Their extraction, purification and analysis are simple and fast, making them potential substitutes for their synthetic equivalents

    Pomegranate (Punica granatum L.): A medicinal plant with myriad biological properties - A short review

    Get PDF
    The pomegranate, Punica granatum L., which can be found throughout the Mediterranean region, in Southeast Asia, California and Arizona in USA was in ancient times referred as possessing powers of fertility, abundance and good luck (fruit). The biological properties of extracts (antimicrobial, antioxidant, anticancer, anti-inflammatory, among other properties) obtained from several parts of pomegranate is reported in the present work. Due to such properties, the extracts have been used in therapeutics, such as in the prevention of infection, inflammation, cancer, among other applications. However, other aspects are also referred in the present work such as the good practices of culture and fruit preservation, search of new compounds, selection of cultivars through biotechnological techniques for obtaining juice or fruits ready to eat. Such compilation of information was based on the search in the ISI Web of Knowledge (Thomson Reuters) from 2009 up to the beginning of October 2010

    Production and application of textile materials

    Get PDF
    This specialized publication is dedicated to technical and technological solutions in textile production. Engineering solutions in the production of fibers and fabrics for both technical and domestic use are considered. Particular attention in the book is given to the study of textile products for biomedical applications. Modern medical fabrics and fibers are used as dressing and suture material and significantly accelerate the recovery processes after surgical operations and burn injuries. Fibers and fabrics are currently often used as a reinforcing element in the production of various composite materials, which are often used in mechanical engineering and in the construction sector. A separate chapter is devoted to textile reinforcing materials. Environmental problems in textile production are mainly related to the dyeing process and the chemical treatment of fabrics and fibers. Some aspects of textile dyeing and wastewater treatment processes are also discussed in this publication. The book will be useful to specialists involved in textile production and related industries

    Historic dye analysis: method development and new applications in cultural heritage

    Get PDF
    A review of the main natural dyes (particularly yellow flavonoids and red anthraquinones) and proteinaceous substrates used in Historical Tapestries and North American porcupine quill work was undertaken, and is summarised in Chapter 1. The analysis of natural dyes which have been used on museum artefacts other than textiles has received little systematic study, particularly those of non-European origin. In this research, the use of Ultra Performance Liquid Chromatography (UPLC) for study of natural dyes found on historical textiles and ethnographical objects decorated with porcupine quill work is explored; this required a transfer of existing analytical protocols and methodology. The advantages of using Ultra Performance Liquid Chromatography (UPLC) was evaluated through a method development based on the separation and quantification of ten flavonoid and anthraquinone dyes as described in Chapter 2. These methods were then applied to the characterisation of the dye sources found on a group of sixteenth century historical tapestries which form an important part of the Burrell Collection in Glasgow and are believed to have been manufactured in an English workshop (Chapter 3) and also to the analysis of some late nineteenth century North American porcupine quill work from a collection owned by National Museums Scotland (Chapter 5); allowing exciting conclusions to be drawn in each case about the range of dyestuffs used in their manufacture. The second aim of this research was the development of methodology for the non-invasive quantification of metal ion residues on porcupine quill substrates. This was achieved through a comparative study of reference porcupine quills prepared in-house with dyebaths containing a range of metal ion concentrations (copper and tin). The concentration of metal ions sorbed by the porcupine quills was then quantified with Inductively Coupled Plasma (ICP) coupled to Optical Emission Spectrometry (OES) and non-invasive Particle Induced X-Ray Emission analysis (PIXE) coupled with Rutherford Backscattering Spectrometry (RBS) as described in Chapter 4. The responses provided by the different methods were compared and they were then applied to the study of micro-samples collected from mid-nineteenth century Northern Athapaskan porcupine quill work. Unexpectedly, the use of UPLC analysis and RBS-PIXE analysis allowed the characterisation of traded European natural dyes used with metallic mordants (copper and tin) on these samples, highlighting how European contact impacted on traditional Athapaskan porcupine quill work in the late nineteenth century (Chapter 5)

    Directional water-transport fabrics achieved by wettablity gradient from superhydrophobicity to hydrophilicity

    Full text link
    In this study, we demonstrate that fabrics having a wettability gradient from superhydrophobic to hydrophilic through the thickness direction show a novel directional water transfer effect: water can transfer only from the superhydrophobic to the hydrophilic side, but not in the opposite direction unless an external force is applied. A sol-gel technology was used to prepare a superhydrophobic coating on fabrics, and the coated fabrics showed water contact-angle as high as 165°. When the coated fabric was subjected to a photochemistry treatment from one fabric side, the irradiated surface turned hydrophilic permanently, while the back side still maintained the superhydrophobicity. The treated fabric can transfer water droplet rapidly from hydrophobic to hydrophilic side, and the pressure allowing water breakthrough the fabric is different considerably between the two fabric sides. The directional water transfer effect is also affected by the wettability gradient. Such a directional water transfer coating may be useful to develop new functional fabrics for defence applications

    International Conference on Advances in Biosciences and Biotechnology – ICABB-2019

    Get PDF
    International Conference on Advances in Biosciences and Biotechnology – ICABB-201

    Proceedings of the 29th International Symposium on Analytical and Environmental Problems

    Get PDF

    Characterization of microporous silica-based membranes by calorimetric analysis

    Get PDF

    Biofunctionalization of natural fiber-reinforced biocomposites for biomedical applications

    Get PDF
    In the last ten years, environmental consciousness has increased worldwide, leading to the development of eco-friendly materials to replace synthetic ones. Natural fibers are extracted from renewable resources at low cost. Their combination with synthetic polymers as reinforcement materials has been an important step forward in that direction. The sustainability and excellent physical and biological (e.g., biocompatibility, antimicrobial activity) properties of these biocomposites have extended their application to the biomedical field. This paper offers a detailed overview of the extraction and separation processes applied to natural fibers and their posterior chemical and physical modifications for biocomposite fabrication. Because of the requirements for biomedical device production, specialized biomolecules are currently being incorporated onto these biocomposites. From antibiotics to peptides and plant extracts, to name a few, this review explores their impact on the final biocomposite product, in light of their individual or combined effect, and analyzes the most recurrent strategies for biomolecule immobilization.PTDC/CTM-TEX/28074/2017; Portuguese Foundation for Science and Technology (FCT), FEDER funds by means of Portugal 2020 Competitive Factors Operational Program (POCI) and the Portuguese Government(OE) by means of projects POCI-01-0145-FEDER-028074 and UID/CTM/00264/202

    Theme Issue Honoring Professor Robert Verpoorte's 75th Birthday: Past, Current and Future of Natural Products Research

    Get PDF
    This theme issue is to celebrate Professor Robert Verpoorte’s 75th birthday. Prof. Verpoorte has been working in Leiden University over 40 years. There is no need to dwell upon the contributions of Dr. Verpoorte to plant-derived natural products research during his whole life. Dr. Verpoorte was a highly productive scientist throughout his academic career, with over 800 scientific publications in the form of research papers, books, and book chapters. His research interests are very diverse, cover- ing numerous topics related to plant-based natural products such as plant cell biotech- nology, biosynthesis, metabolomics, genetic engineering, and green technology, as well as the isolation of new biologically active compounds. He has left indelible footprints in all these fields, and he is widely recognised as a pioneer in the work of the biosynthesis of indole alkaloids, NMR-based metabolomics, and green technology in natural products production. As close friends and colleagues who have been in nearly daily contact with him over the last 20 years viewing all of these remarkable scientific contributions, we felt compelled to recognize this by the publication of a Special Issue of this journal dedicated to him.Thus, this Special Issue has now finally been released with the help of many of his colleagues and former students as a token of our gratitude to his impressive work.The Special Issue covers five main natural products topics: (1) chemical profiling and metabolomics, (2) separation/isolation and identification of plant specialized metabolites, (3) pharmacognosy of natural products to identify bioactive molecules from natural prod- ucts, (4) novel formulation of natural products, and (5) overview of natural products as a source of bioactive molecules
    • …
    corecore