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Structure of xyloglucan; principal component of the hemicelluloses. The heptamer block is shown (glucan 4 -xylose 3 ). In blue backbone β -D-glucans; in red α -D-xylose; in black α -D-galactose and in
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RG-II has several kinds of substituents including 11 to 12 different glycosyl residues, some of them rare sugars in nature, like 2- O-methyl xylose, 2- O-methyl fucose, aceric acid, 2-keto-3-deoxy-D-lyxo heptulosaric acid (Dha) and 2-keto-3-deoxy-D-manno octulosonic acid (Kdo) [ 27- 30]. About 28-36 individual sugars, interconnected by more than 20...
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... are branched with α-D-xylose linked to C-6 of the backbone. The most frequently xyloglucan structure in dicotyledonous flowering plants is the repeating heptamer integrated by four glucans residues with α-D-xylose substituents in three constitutive glucans of the backbone, followed by a single unsubstituted glucan residue (Figure 1). The presence of this repeating heptamer block is an indicator of the presence of XyG polysaccharides in dicots species [8]. ...
Citations
... In the case of pectins, CHARMM-GUI software (version 3.8) [58,59] was used to generate pectin chains (HG and RG1) with a backbone length of 80 saccharides, as described in [60]. For HG, the backbone was modified by 32 methyl esterifications at the C-6 carboxyl position (low-methyl esterified HGs) and by 32 O-acetylations at the O-2 or O-3 position [60,61].In this study, an RG1 model similar to the one presented in Figure 3.19 of [62] was used. Its backbone had 24 branches, namely eight arabinofuranoses, eight galactoses, and eight mixes of these two. ...
The goal of the research is to describe the aggregation process inside the mucilage produced by plant seeds using molecular dynamics (MD) combined with time series algorithmic analysis based on the recurrence plots. The studied biological molecules model is seed mucilage composed of three main polysaccharides, i.e. pectins, hemicellulose, and cellulose. The modeling of biological molecules is based on the assumption that a classical–quantum passage underlies the aggregation process in the mucilage, resulting from non-covalent interactions, as they affect the macroscopic properties of the system. The applied recurrence plot approach is an important tool for time series analysis and data mining dedicated to analyzing time series data originating from complex, chaotic systems. In the current research, we demonstrated that advanced algorithmic analysis of seed mucilage data can reveal some features of the dynamics of the system, namely temperature-dependent regions with different dynamics of increments of a number of hydrogen bonds and regions of stable oscillation of increments of a number of hydrophobic–polar interactions. Henceforth, we pave the path for automatic data-mining methods for the analysis of biological molecules with the intermediate step of the application of recurrence plot analysis, as the generalization of recurrence plot applications to other (biological molecules) datasets is straightforward.
... Functioning as natural decomposers, Trichoderma spp. accelerate the breakdown of organic materials, particularly hemicellulose and cellulose present in plant cell walls (Ochoa-Villarreal et al., 2012). Through enzymatic actions, Trichoderma virens effectively degrades these substances, releasing nutrients and energy that not only support its own growth but also foster the flourishing of other microorganisms in the soil. ...
... RG-I is a complex side chain composed of alternating galacturonic acid and rhamnose residues that is connected to the HG backbone [77]. The length of the RG-I backbone can range between 20 and 300 repeating units. ...
... RG-II is the most complex and structurally unique component of pectin. It consists of a branched backbone of alternating galacturonic acid and rhamnose residues, with various side chains containing arabinan, apiose, and xylose residues [67,74,77]. RG-II has great crosslinking capabilities [79], which help to generate robust and stable pectin hydrogels. ...
Pectin hydrogels have garnered significant attention in the food industry due to their remarkable versatility and promising properties. As a naturally occurring polysaccharide, pectin forms three-dimensional (3D) hydrophilic polymer networks, endowing these hydrogels with softness, flexibility, and biocompatibility. Their exceptional attributes surpass those of other biopolymer gels, exhibiting rapid gelation, higher melting points, and efficient carrier capabilities for flavoring and fat barriers. This review provides an overview of the current state of pectin gelling mechanisms and the classification of hydrogels, as well as their crosslinking types, as investigated through diverse research endeavors worldwide. The preparation of pectin hydrogels is categorized into specific gel types, including hydrogels, cryogels, aerogels, xerogels, and oleogels. Each preparation process is thoroughly discussed, shedding light on how it impacts the properties of pectin gels. Furthermore, the review delves into the various crosslinking methods used to form hydrogels, with a focus on physical, chemical, and interpenetrating polymer network (IPN) approaches. Understanding these crosslinking mechanisms is crucial to harnessing the full potential of pectin hydrogels for food-related applications. The review aims to provide valuable insights into the diverse applications of pectin hydrogels in the food industry, motivating further exploration to cater to consumer demands and advance food technology. By exploiting the unique properties of pectin hydrogels, food formulations can be enhanced with encapsulated bioactive substances, improved stability, and controlled release. Additionally, the exploration of different crosslinking methods expands the horizons of potential applications.
... Homogalacturonans (HG), rhamnogalacturonans I (RGI), and rhamnogalacturonans II (RGII) are the main representatives of pectins. Homogalacturonan (HG), a linear homopolymer composed of D-galacturonic acid, can be methylated and/or acetylated (Costa and Plazanet 2016;Ochoa-Villarreal et al. 2012). Rhamnogalacturonan I (RGI) is a branched polymer of repeating sequences of disaccharides composed of α-1,4-galacturonic acid and α-1,2-rhamnose residues. ...
... Similar to xyloglucan, arabinoxylans with fewer sidechains have been found to interact with cellulose microfibrils (Heredia et al. 1995;Lampugnani et al. 2018;Ochoa-Villarreal et al. 2012). In contrast to xyloglucans, arabinoxylans may also contain glucosyluronic acid residues giving acidic properties, which in turn enable arabinoxylans to interact with other polysaccharides (Albersheim et al. 2010). ...
Recent studies on the plant cell wall assume that hemicellulosic polysaccharides interact closely with cellulose microfibrils through hydrophobic forces. In contrast, hydrogen bonds, which are still emphasized, play a significant role in stabilizing the conformation of the hemicellulose bound on the cellulose surface. However, there is still no consensus on the nature of the interactions between these polysaccharides and on potential interactions of pectins also with cellulose microfibrils. Since the natural plant cell wall is a very complex system, studies of model systems (in vitro) provide information about the interaction between plant polysaccharides. Adsorption studies, which describe the interactions between non-cellulosic polysaccharides and cellulose, are one of these methods. They help to determine the type of these interactions and characterize the adsorption process. This review aims to summarize the knowledge of the interactions between cellulose and representatives of hemicelluloses and pectins, which was mainly provided by adsorption studies.
Graphical abstract
... Hemicellulose is another major component of both stem and leaf cell walls, and consists mainly of a backbone of β-1,4 linked xylose residues (xylans), a diverse group of polysaccharides (McNeill et al. 1984). The xylan polymer backbone is bonded to the cellulose fibrils and this structure is complicated by side-chains of α-(1,2) linked glucuronic acid, 4-o-methyl glucuronic acid, acetic acid, and arabinose residue, known as arabinoxylans and glucuronoarabinoxylans (Ochoa-Villarreal et al. 2012). Xylan polymers can then be cross-linked to other hemicellulose backbones or lignin. ...
Supplementation of exogenous enzymes in ruminant diets is an alternative solution to increase dietary energy and fiber digestibility and thus decrease production costs. A systematic review was conducted, resulting from 21 studies with 76 experimental records, divided by animal species (dairy cows or dairy sheep). A descriptive statistical analysis of milk production and milk composition was carried out. It was found that xylanases or the combination of xylanases with cellulases produced more milk and improved the percentage of fat, lactose, protein, and total solids. Future studies should focus on the composition of the diet, the origin of the enzyme, and the amount and number of enzymes added.
... Pectin can be categorised into smooth or hairy regions based on the level of branching sidechains that are present. HG comprises chains of 1,4-linked α-D-galacturonic acid and as there are no branching chains extending from the HG backbone, it is classified as smooth [15]. RGI contains repeating units of L-rhamnose and D-galacturonic acid in its backbone. ...
Plant parasitic nematodes need to overcome the barrier presented by the plant cell wall in order to invade their host. A variety of plant cell wall degrading enzymes are present in endoparasitic nematodes including enzymes that degrade cellulose (beta 1,4 endoglucanases) and various pectin components. We describe the cloning and functional analysis of genes encoding GH53 arabinogalactan endo-1,4-beta-galactosidases from three related plant parasitic nematodes Globodera rostochiensis, Globodera pallida and Rotylenchulus reniformis. Phylogenetic and structural analyses strongly indicate that these genes have been acquired by horizontal gene transfer from bacteria. We show that the genes are expressed at invasive stages of the parasites in the secretory gland cells. We also demonstrate that the enzymes from these species are biochemically active, showing the expected hydrolytic enzymatic activity when galactan was used as a substrate. This work further demonstrates the importance of cell wall degradation to the success of the parasitic process and the extensive role that horizontal gene transfer has played in the evolution of plant parasitism by nematodes.
... significantly increased the decomposition rate of empty fruit bunches from 4 to 6 months to 21-45 days. Ochoa-Villarreal et al. (2012) stated that the plant cell wall consists of cellulose and hemicellulose responsible for its rigidity. Both of these compounds can be broken down by Trichoderma due to their capability to produce cell wall-degrading enzymes. ...
... The plant cell wall consists of cellulose, and hemicellulose could be broken down by Trichoderma spp. due to its production of cell wall degrading enzymes (Amira et al., 2011;Ochoa-Villarreal et al., 2012). It resulted in the slow release of nutrients and higher sequestration for the higher period. ...
... Trash incorporation and inoculation of Trichoderma increased the population of bacteria in the soil. Increased bacterial population affected bio decomposition processes (Amira et al., 2011;Ochoa-Villarreal et al., 2012; Bond-Lamberty et al., 2016) and increased soil respiration. Soil microbial biomass carbon represents a fraction of organic carbon. ...
Soil organic carbon management is a key component for crop growth and provides sustainability in the cropping system. In subtropical India, soil organic carbon in agricultural soils continuously decreases, and most soils have very low organic carbon content. Trash management in the sugarcane ratoon crop improves soil quality parameters and supports crop growth favourably. Further inoculation of Trichoderma has also shown a synergistic response with trash application on nutrient availability in the ratoon crop. Improving soil quality also influences physiological activity, net photosynthesis, and crop yield. The present investigation aimed to determine the effect of trash management and Trichoderma application on changes in soil chemical and biological properties besides net photosynthetic rate, dry matter accumulation, and nutrient uptake by sugarcane ratoon crop to assess the sustainability of the system. Thus a field experiment was conducted with four treatments viz., (i) sugarcane trash mulching without Trichoderma harzianum, (ii) trash removal without Trichoderma, (iii) trash mulching + Trichoderma and (iv) trash incorporation + Trichoderma in a randomized block design (RBD) and five replications. Trash incorporation and inoculation of Trichoderma influenced net photosynthetic rate (NPR) positively. The lowest NPR (19.14 µmol/m²/s) was recorded under trash removal without Trichoderma. An increment of 16.15 % in total dry matter accumulation was recorded under trash incorporation + Trichoderma compared to trash removal without Trichoderma. Trash incorporation and Trichoderma accumulated the highest N in leaf, cane, and roots. Thus NPK uptake could be improved by the application of trash and Trichoderma application. The mean available K content in soil was significantly improved by 12.48 % compared to the initial level. An improvement of 33.6 kg K/ha was recorded after the harvest of the ratoon crop. The highest soil organic carbon (15.28 Mg/ha) was recorded with mulching of sugarcane trash under Trichoderma inoculation. The highest bacterial population was recorded under trash incorporation with Trichoderma. Soil microbial biomass carbon (SMBC) could be improved by 1.82 times under trash mulching + Trichoderma as compared to the initial status. Trash incorporation and Trichoderma application recorded the highest mean cane weight (1053 g) in ratoon crop. Trash incorporation+ Trichoderma registered an increase of 16.19 % increase in sugarcane yield as compared to trash removal without Trichoderma. However, sugar yield in a similar treatment was improved by 27.8 %. Thus trash application along with Trichoderma harzianum holds great promise in sustaining soil health and sugarcane and sugar yields in subtropical India.
... Among these hydrocolloids is pectin, a group of heteropolysaccharides usually present in plant cell walls, playing an important role in many biological functions. 1 This polysaccharide with a backbone of D-galacturonic acids (GalA) linked by α-1, 4 glycosidic bonds is mainly consisted of homogalacturonan (HG) and rhamnogalacturonan-I and a small content of rhamnogalacturonan-II (RG-II) and xylogalacturonan (XG). 2,3 Also, pectin is well known for its gelling, emulsifying, stabilizing, and thickening capabilities. ...
BACKGROUND
With production of over 6 million tonnes a year of sesame, its capsules are considered to be an unutilized waste. In this study, extraction of pectin from this novel source was optimized using a green method, and the functional and physiochemical characteristics of the resultant pectin were compared to commercial pectin.
RESULTS
In this study, the sesame capsule pectin (SCP) extraction conditions were optimized to reach maximum yield, and the results showed that the maximum pectin extraction yield (138 g kg⁻¹) was obtained under optimal conditions (microwave power 700 W, irradiation time 5 min, pH 1.5, and liquid‐to‐solid ratio 41.8 (mL g⁻¹). The results showed that the pectin was low methoxyl type with a galacturonic acid content of 670 g kg⁻¹. The extracted pectin had a high molecular weight (341 kDa) and surface charge (34.09 ± 1.88 mV) and exhibited 66% DPPH radical scavenging. The obtained results from ¹H‐nuclear magnetic resonance and Fourier transform infrared spectra validated the presence of pectin structure in the extracted sample.
CONCLUSION
Sesame capsule pectin, when compared to commercial pectin, demonstrated better functional properties in terms of emulsifying properties, oil holding capacity, foaming capacity and antioxidant activity. SCP showed similar properties in comparison to its commercial counterpart, which suggests that it could well be considered as a new and suitable source for pectin extraction. © 2022 Society of Chemical Industry.
... Although there are many potential applications in bioprocessing, lignocellulose biomass is still largely untapped due to the stability of the cell wall, i.e., resistance to deconstruction, relative abundance and interaction between cell wall components [22]. Therefore, as demonstrated by Ochoa-Villarreal et al., in order to effectively use the cell wall as a renewable source of useful molecules, it is important to increase knowledge on how to assemble the wall in terms of composition and structure [23]. The cell walls of commelinoid monocots, including grasses, differ from other plant groups. ...
Miscanthus is a perennial wild plant that is vital for the production of paper and roofing, as well as horticulture and the development of new high-yielding crops in temperate climates. Chromosome-level assembly of the ancient tetraploid genome of miscanthus chromosomes is reported to provide resources that can link its chromosomes to related diploid sorghum and complex polyploid sugarcane. Analysis of Miscanthus sinensis and Miscanthus sacchariflorus showed intense mixing and interspecific hybridization and documented the origin of a high-yielding triploid bioenergetic plant, Miscanthus × giganteus. The Miscanthus genome expands comparative genomics functions to better understand the main abilities of Andropogoneae herbs. Miscanthus × giganteus is widely regarded as a promising lignocellulosic biomass crop due to its high-biomass yield, which does not emit toxic compounds into the environment, and ability to grow in depleted lands. The high production cost of lignocellulosic bioethanol limits its commercialization. The main components that inhibit the enzymatic reactions of fermentation and saccharification are lignin in the cell wall and its by-products released during the pre-treatment stage. One approach to overcoming this barrier could be to genetically modify the genes involved in lignin biosynthesis, manipulating the lignin content and composition of miscanthus.
... The role of cellulase was studied in textile industries, waste treatment, and fermentation of sugars and ethanol. Moreover, they are required in the textile industry, animal feed, food industry, detergents, chemicals, pulp, and paper [169]. ...
Marine microorganisms represent virtually unlimited sources of novel biological compounds, and can survive extreme conditions. Cellulases, a group of enzymes which are able to degrade cellulosic materials, are in high demand in various industrial and biotechnological applications, such as in the medical and pharmaceutical industry, food, fuel, agriculture and their applications in single cell protein and as probiotics in aquaculture. The cellulosic biopolymer is a renewable resource and is a linearly arranged polysaccharide of glucose, with repeating units of disaccharide, connected via β-1,4-glycosidic bonds, which are broken down by cellulase. A great deal of biodiversity resides in the ocean, and marine systems produce a wide range of distinct, new bioactive compounds which can remain available but dormant for many years. The marine environment is filled with biomass from known and unknown vertebrates and invertebrate microorganisms, with much potential for use in medicine and biotechnology. Hence, complex polysaccharides derived from marine sources are a rich resource of microorganisms equipped with enzymes for polysaccharides degradation. Marine cellulases extracts from the isolates were tested for their functional role in degrading seaweed and modifying wastes to low molecular fragments. They purify and renew their environments by eliminating possible feedstocks of pollution. The aim of this review is to survey the various types of marine cellulase producers, to assess the ability of these microorganisms for producing these enzymes, and their subsequent biotechnological applications.
