scholarly journals STRUCTURAL AND CHEMICAL CHARACTERISTIC OF PECTIN FROM PICEA ABIES GREENERY

2020 ◽  
pp. 59-71
Author(s):  
Evgeniy Gennad'yevich Shakhmatov ◽  
Elena Nikolayevna Makarova

The present work aimed to determine structural features of polysaccharides derived from the P. abies foliage by extraction with a (NH4)2C2O4 solution. The isolated polysaccharide was studied in detail by the methods of ion exchange chromatography, partial acidic hydrolys and NMR spectroscopy. It was shown that this polysaccharide contained polymers of various structures. The major constituents of PAO were low-methoxyl and low-acetylated 1,4-a-D-galacturonan and by minor parts of partly 2-O- and/or 3-O- acetylated rhamnogalacturonan-I (RG-I). The side carbohydrate chains of the branched region of RG-I were represented predominantly by highly branched 1,5-a-L-arabinan and minor portions of 1,4-β-D-galactan. In addition to the dominant pectins, polysaccharide PAO contained binding glycans of the glucomannans class, which indicated a close interaction of these polysaccharides in the cell walls. Thus, the structural features of pectin woody P. abies, extracted with a solution of (NH4)2C2O4, were first determined. It can be concluded that P. abies woody greens, a large tonnage waste from the wood processing industry, can be considered as a potential source of pectin substances. The results of studying the structure of components of woody green P. abies can be the basis for the development and improvement of new technologies for the integrated use of this raw material.

1990 ◽  
Vol 269 (2) ◽  
pp. 393-402 ◽  
Author(s):  
P Ryden ◽  
R R Selvendran

1. Polymers were solubilized from the cell walls of parenchyma from mature runner-bean pods with minimum degradation by successive extractions with cyclohexane-trans-1,2-diamine-NNN′N′-tetra-acetate (CDTA), Na2CO3 and KOH to leave the alpha-cellulose residue, which contained cross-linked pectic polysaccharides and Hyp-rich glycoproteins. These were solubilized with chlorite/acetic acid and cellulase. The polymers were fractionated by anion-exchange chromatography, and fractions were subjected to methylation analysis. 2. The pectic polysaccharides differed in their ease of extraction, and a small proportion were highly cross-linked. The bulk of the pectic polysaccharides solubilized by CDTA and Na2CO3 were less branched than those solubilized by KOH. There was good evidence that most of the pectic polysaccharides were not degraded during extraction. 3. The protein-containing fractions included Hyp-rich and Hyp-poor glycoproteins associated with easily extractable pectic polysaccharides, Hyp-rich glycoproteins solubilized with 4M-KOH+borate, the bulk of which were not associated with pectic polysaccharides, and highly cross-linked Hyp-rich glycoproteins. 4. Isodityrosine was not detected, suggesting that it does not have a (major) cross-linking role in these walls. Instead, it is suggested that phenolics, presumably linked to C-5 of 3,5-linked Araf residues of Hyp-rich glycoproteins, serve to cross-link some of the polymers. 5. There were two main types of xyloglucan, with different degrees of branching. The bulk of the less branched xyloglucans were solubilized by more-concentrated alkali. The anomeric configurations of the sugars in one of the highly branched xyloglucans were determined by 13C-n.m.r. spectroscopy. 6. The structural features of the cell-wall polymers and complexes are discussed in relation to the structure of the cell walls of parenchyma tissues.


2013 ◽  
Vol 75 (6) ◽  
pp. 1018-1027 ◽  
Author(s):  
Kieran J.D. Lee ◽  
Valérie Cornuault ◽  
Iain W. Manfield ◽  
Marie-Christine Ralet ◽  
J. Paul Knox

2005 ◽  
Vol 130 (6) ◽  
pp. 936-942 ◽  
Author(s):  
Robert P. Sabba ◽  
Edward C. Lulai

Potato (Solanum tuberosum L.) periderm forms a barrier at the surface of the tuber that protects it from infection and dehydration. Immature periderm is susceptible to excoriation (skinning injury), which results in costly storage loses and market quality defects. The periderm consists of three different cell types: phellem (skin), phellogen (cork cambium), and phelloderm (parenchyma-like cells). The phellogen serves as a lateral meristem for the periderm and is characterized by thin radial walls that are labile to fracture while the periderm is immature and the phellogen is actively dividing, thus rendering the tuber susceptible to excoriation. As the periderm matures the phellogen becomes inactive, its cell walls thicken and become resistant to fracture, and thus the tuber becomes resistant to excoriation. Little is known about the changes in cell wall polymers that are associated with tuber periderm maturation and the concurrent development of resistance to excoriation. Various changes in pectins (galacturonans and rhamnogalacturonans) and extensin may be involved in this maturational process. The objectives of this research were to compare immunolabeling of homogalacturonan (HG) epitopes to labeling of rhamnogalacturonan I (RG-I) and extensin epitopes to better understand the depositional patterns of these polymers in periderm cell walls and their involvement in tuber periderm maturation. Immunolabeling with the monoclonal antibodies JIM5 and JIM7 (recognizing a broad range of esterified HG) confirmed that HG epitopes are lacking in phellogen walls of immature periderm, but increased greatly upon maturation of the periderm. Labeling of a (1,4)-β-galactan epitope found in RG-I and recognized by the monoclonal antibody LM5 was abundant in phelloderm cell walls, but sparse in most phellem cell walls. LM5 labeling was very sparse in the walls of meristematically active phellogen cells of immature periderm, but increased dramatically upon periderm maturation. Deposition of a (1,5)-α-l-arabinan epitope found in RG-I and recognized by LM6 was abundant in phelloderm and phellogen cell walls, but was sparse in phellem cell walls. LM6 labeling of phellogen walls did not change upon periderm maturation, indicating that different RG-1 epitopes are regulated independently during maturation of the periderm. Labeling with the monoclonal antibody LM1 for an extensin epitope implied that extensin is lacking in phellem cell walls, but is abundant in phelloderm cell walls. Phellogen cell walls did not label with LM1 in immature periderm, but were abundantly labeled with LM1 in mature periderm. These immunolabeling studies identify pectin and extensin depositions as likely biochemical processes involved in the thickening and related strengthening of phellogen walls upon inactivation of the phellogen layer as a lateral meristem and maturation of the periderm in potato tuber. These results provide unique and new insight into the identities of some of the biological processes that may be targeted in the development of new technologies to enhance resistance to tuber skinning injury for improved harvest, handling and storage properties.


1978 ◽  
Vol 175 (3) ◽  
pp. 1033-1042 ◽  
Author(s):  
I R Poxton ◽  
E Tarelli ◽  
J Baddiley

The well-known immologically active component of pneumococci, C-polysaccharide, is a teichoic acid that can be isolated from the cell walls and purified by Sephadex and ion-exchange chromatography. Further details of the structure of C-teichoic acid were established by chemical degradation, including hydrolysis in acid and alkali, treatment with HF, periodate oxidation and methylation. In addition, the use of 13C n.m.r. has confirmed some of these structural features and resulted in a proposal for the order of substituents, the location of positions of substitution and the configuration of anomeric centres in the repeating unit of the polymer.


Vsyo o myase ◽  
1918 ◽  
pp. 44-47
Author(s):  
V.V. Nasonova ◽  
◽  
A.A. Motovilina ◽  
E.K. Tunieva ◽  
T.G. Kuznetsova ◽  
...  

2019 ◽  
Vol 26 (35) ◽  
pp. 6399-6411 ◽  
Author(s):  
Cláudia Nunes ◽  
Manuel A. Coimbra

Marine environments have a high quantity and diversity of sulfated polysaccharides. In coastal regions brown algae are the most abundant biomass producers and their cell walls have fucosecontaining sulfated polysaccharides (FCSP), known as fucans and/or fucoidans. These sulfated compounds have been widely researched for their biomedical properties, namely the immunomodulatory, haemostasis, pathogen inhibition, anti-inflammatory capacity, and antitumoral. These activities are probably due to their ability to mimic the carbohydrate moieties of mammalian glycosaminoglycans. Therefore, the FCSP are interesting compounds for application in health-related subjects, mainly for developing scaffolds for delivery systems or tissue regeneration. FCSP showed potential for these applications also due to their ability to form stable 3D structures with other polymers able to entrap therapeutic agents or cell and growth factors, besides their biocompatibility and biodegradability. However, for the clinical use of these biopolymers well-defined reproducible molecules are required in order to accurately establish relationships between structural features and human health applications.


1983 ◽  
Vol 34 (3) ◽  
pp. 241 ◽  
Author(s):  
CW Ford

Stem cell walls of pangola grass (Digitaria decumbens) were ground to two particle sizes (c. 1 and 0.1 mm diameter), and incubated with cellulase (ex. Trichoderma viride) for varying times before and after delignification. Total cell walls finely ground (0.1 mm) with a Spex Shatterbox mill were initially degraded more rapidly (to 24 h) than delignified 1 mm particles. Thereafter the delignified material was solubilized to a greater extent. Subsequent specific determinations of cell wall polysaccharides indicated that delignification increased the rate of hemicellulose degradation to a greater extent than did particle size reduction, whereas the opposite was found for cellulose. The difference between delignified and Spex-ground residues, in terms of the amount of polysaccharide digested, was much greater for cellulose than hemicellulose. It is concluded that structural features play a more important role in limiting cellulase degradation of cellulose than does association with lignin, the reverse being so for hemicellulose.


Author(s):  
Krzysztof Nadolny ◽  
Wojciech Kapłonek ◽  
Marzena Sutowska ◽  
Paweł Sutowski ◽  
Piotr Myśliński ◽  
...  

AbstractRaw pine wood processing and especially its mechanical processing constitute a significant share among technological operations leading to obtaining a finished product. Stable implementation of machining operations, ensuring long-term repeatable processing results depends on many factors, such as quality and invariability of raw material, technical condition of technological equipment, adopted parameters of work, qualifications and experience of operators, as well as preparation and properties of the machining tools used. It seems that the greatest potential in the search for opportunities to increase the efficiency of machining operations has the modification of machining tools used in it. This paper presents the results of research work aimed at determining how the life of cutting tools used in planing operations of wet pine wood is affected by the application of chromium aluminum nitride (AlCrN) coating to planar industrial planing knives in the process of physical vapour deposition. For this purpose operational tests were carried out under production conditions in a medium-sized wood processing company. The study compares the effective working time, rounding radius, the profile along the knife (size of worn edge displacement, wear area of the cutting edge), selected texture parameters of the planar industrial planing knife rake face and visual analyses of cutting edge condition of AlCrN-coated planar knives and unmodified ones. The obtained experimental results showed the possibility of increasing the life of AlCrN-coated knives up to 154% compared to the results obtained with uncoated ones. The proposed modification of the operational features of the knives does not involve any changes in the technological process of planing, does not require any interference with the machining station nor its parameters, therefore enabling rapid and easy implementation into industrial practice.


2021 ◽  
pp. 87-90
Author(s):  
М.Ж. Кизатова ◽  
Д.А. Абдуллаева

Статья посвящена важности пектиновых веществ, а также расширению сферы использования лекарственного растительного сырья. В качестве лекарственного растительного сырья представлены технологии получения пектинового экстракта из плодов шиповника, которые встречаются на территории Казахстана 25 видов. Применение пектина в медицине. The article is devoted to the importance of pectin substances, as well as to the expansion of the use of medicinal plant raw materials. As a medicinal plant raw material, technologies for obtaining pectin extract from rosehip fruits, which are found in 25 species on the territory of Kazakhstan, are presented. The use of pectin in medicine


Nafta-Gaz ◽  
2021 ◽  
Vol 77 (3) ◽  
pp. 208-214
Author(s):  
Michał Pajda ◽  
◽  
Wojciech Mazela ◽  

The aim of the work was to present the issue of eco-efficiency, based on the PN-EN ISO 14045:2012 standard in relation to the production of fatty acid methyl esters (FAME). The ecoefficiency analysis takes into account economic and environmental aspects in the improvement of products and processes / technologies. Eco-efficiency considers the product and technology throughout the life cycle, from the construction phase, through use to decommissioning. The impact on the natural environment is assessed on the basis of: consumption of energy, materials, dust and gas emissions, waste and sewage. Total costs include: production costs, raw material costs, costs during the use phase including maintenance, repair and operating costs, product disposal or recycling. The eco-efficiency analysis is helpful in making decisions regarding the selection of a new product or designing a new technology, and enables the selection of the variant that is the most economical and has the least possible impact on the natural environment. These issues are particularly important in the case of biofuels. The rapid growth of their production and the European Union’s policy, which aims to increase the share of energy from renewable sources, cause concerns of many experts regarding the threats related to the production of biofuels, both for the environment and food security. In particular, efforts are made to minimize the amount of waste and residues by implementing the idea of a circular economy. This approach promotes the development of new technologies that are more environmentally friendly. Due to the regulations set out in the RED and RED II Directives, there is a chance that the biofuels will have a less negative impact on the environment. This results from the obligation to certify compliance with the sustainability criteria, which is carried out by voluntary systems recognized by the European Commission, such as the KZR INiG System.


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