Polysaccharide Arabinogalactan Research Articles

The Use of Polysaccharide Matrices as a Basis for the Formation of Tellurium Nanoparticles with Different Morphologies

The widening of possible areas of practical uses for zero-valent tellurium nanoparticles (Te0NPs) from biomedicine to optoelectronic and thermoelectric applications determines the actuality of the development of simple and affordable methods for their preparation. Among the existing variety of approaches to the synthesis of Te0NPs, special attention should be paid to chemical methods, and especially to “green” approaches, which are based on the use of precursors of tellurium in their powder bulk form and natural galactose-containing polysaccharides—arabinogalactan (Ar-Gal), galactomannan—(GM-dP) and κ-carrageenan (κ-CG) acting as ligands stabilizing the surface of the Te0NPs. The use of basic-reduction system “N2H4 H2O-NaOH” for preliminary activation of bulk-Te and Ar-Gal, GM-dP and κ-CG allowed us to obtain in aqueous medium a number of stable nanocomposites consisting of Te0NPs stabilized by the polysaccharides’ macromolecules. By varying the precursor ratio, different morphologies of nanoparticles were obtained, ranging from spheres at a polysaccharide/Te ratio of 100:1 to rice-like at a 10:1 ratio. The type (branched, combed, or linear sulfated) of polysaccharide and its molecular weight value determined the size of the nanoparticles. Thus, the galactose-containing polysaccharides that were selected for this study may be promising renewable materials for the production of water-soluble Te0NPs with different morphology on this basis.

Chemical structure elucidation and functional activities comparison of two polysaccharides purified from Citrus reticulata Blanco peels

BackgroundThe Citrus reticulata Blanco peels have been widely adopted as functional food or nutraceuticals for thousands of years. In our study, two polysaccharides from the C. reticulata Blanco peels were obtained and named as CRP-WA and CRP-02A, respectively. After characterization by monosaccharide composition, methylation and NMR, chemical structures of CRP-WA and CRP-02A were elucidated.ResultsAs a result, CRP-WA with Mw of 32.8 kDa was an arabinogalactan polysaccharide composed of (β1 → 3) (β1 → 3,6)-D-Galp, (β1 → 4)-D-Manp and (β1 → 4)-D-Glcp units in the backbone. The CRP-02A with Mw of 70.5 kDa was an arabinogalacturonan type pectin formed by (α1 → 4) (α1 → 3,4)-D-GalpA units in the backbone. Moreover, the surface morphologies and rheological properties of CRP-WA and CRP-02A were quite different from each other. Both of these two polysaccharides possessed good antioxidant activities and immunoregulatory effects on RAW 264.7 cells, in which CRP-02A behaved remarkable antioxidant feature, whereas CRP-WA showed relatively high immunoregulatory activity.ConclusionOur study will provide fundamental information for C. reticulata Blanco-based nutritional foods development.Graphical

Separating the contributions of the magnetic subsystems in antiferromagnetic ferrihydrite nanoparticles by analyzing the magnetization in fields of up to 250 kOe

Contributions of different magnetic subsystems formed in the systems of synthetic ferrihydrite nanoparticles (characterized previously) with an average size of < d>≈2.7 nm coated with polysaccharide arabinogalactan in different degrees have been separated by measuring the dependences of their magnetization M on magnetic field H of up to 250kOe on vibrating sample and pulsed magnetometers. The use of a wide measuring magnetic field range has been dictated by the ambiguity in identifying a linear M(H) portion for such antiferromagnetic nanoparticle systems within the conventional field range of 60–90 kOe. The thorough analysis of the magnetization curves in the temperature range of 100–250 K has allowed the verification of the contributions of (i) uncompensated magnetic moments µun in the superparamagnetic subsystem, (ii) the subsystem of surface spins with the paramagnetic behavior, and (iii) the antiferromagnetic susceptibility of the antiferromagnetically ordered ferrihydrite particle core. As a result, a model of the magnetic state of ferrihydrite nanoparticles has been proposed and the numbers of spins corresponding to magnetic subsystems (i)–(iii) have been estimated. An average magnetic moment μunof ∼ 145μB (μB is the Bohr magneton) per particle corresponds approximately to 30 decompensated spins of iron atoms in a particle (about 3 % of all iron atoms), which, according to the Néel’s hypothesis μun∼<d>3/2, are localized both on the surface and in the bulk of an antiferromagnetically ordered particle. The fraction of free (paramagnetic) spins is minimal in the sample without arabinogalactan coating of the nanoparticle surface (7 %) and is attained 20 % of all iron atoms in the sample with the highest degree of spatial separation of particles. According to this estimation, paramagnetic spins are located mainly on the edges and protruding areas of particles. Most magnetic moments of iron atoms are ordered antiferromagnetically and the corresponding magnetic susceptibility of this subsystem behaves as in an antiferromagnet with the randomly distributed crystallographic axes, i.e., increases with temperature.

Yucca schidigera purpurea-sourced arabinogalactan polysaccharides augments antioxidant capacity facilitating intestinal antioxidant functions

This study isolated and purified a novel homogeneous arabinogalactan polysaccharide from Yucca schidigera extract (YSE), unveiled its unique structure and explored its antioxidant function. Firstly, the antioxidant potential of YSE was demonstrated in piglet trials. A homogeneous polysaccharide with a molecular weight of 24.2 kDa, designated as Yucca schidigera polysaccharide B (YPB), was isolated and purified from YSE. The monosaccharide composition of YPB was Rha, Araf, Galp, and Glcp, whose molar percentages were 2.8 %, 11.6 %, 45.5 %, and 40.0 %, respectively. Methylation analysis combined with 1D and 2D nuclear magnetic resonance showed that YPB was a complex polysaccharide with a main glycosidic linkage pattern of →2)-α-ʟ-Rha-(1 → 3)-β-ᴅ-Galp-(1→3)-β-ᴅ-Galp-(1 → 3)-β-ᴅ-Galp-(1 → 3)-β-ᴅ-Glcp-(1→, and branched Araf and Galp fragments were connected with the main chain through →3,6)-β-ᴅ-Galp-(1→, →3,4)-β-ᴅ-Glcp-(1→, and →2,4)-α-ʟ-Rha-(1→ linkages. Following the in vitro biochemical assays of bioactive components, YPB should be the contributor to the antioxidant activity in YSE. Based on the establishment of oxidative stress model, YPB exhibited strong antioxidant capacity and activated NRF2 pathway, and then provided protection against the damage induced oxidative stress in IPEC-J2 cells and rats. Further analysis with inhibitors found that this antioxidant effect was attributed to its interaction with epidermal growth factor receptor and mannose receptor, and stimulating PI3K/AKT pathway.

Innovative prospects for the creation of biologically active complexes based on a polysaccharide matrix

The possibility of combining complexly soluble arabinogalactan polysaccharides with chitosan polysaccharides to increase the absorption of biologically active substances and compounds characterized by low bioavailability is being considered. Included in the biologically active biopolymer matrix are chitosan succinate, succinic anhydrite, arabinogalactan and dihydroquercetin, respectively, in quantities, wt. %: 3–5.0; 2.0–4.0; 15.0–20.0 and 3.5 can serve as a targeted carrier for the delivery of diagnostic and therapeutic agents, including enzymes, nucleic acids, vitamins, hormones, etc. to certain cells, in particular, hepatocytes (liver parenchyma cells). The high membranotropic properties of arabinogalactan isolated from larch have been established, which allows its use to increase the absorption in the gastrointestinal tract of other functionally active ingredients with low bioavailability. The mechanism of this action is associated with the formation of a binding complex between arabinogalactan and the delivered agent, which has the ability to interact with the asialoglycoprotein cell receptor. Studies have been carried out on the possibility of combining arabinogalactan polysaccharides with chitosan polysaccharides to obtain a biopolymer matrix, which includes chitosan succinate, succinic anhydride and arabinogalactan containing dihydroquercetin not covalently bound to it. Along with the above properties, the effectiveness of using arabinogalactan is shown using the example of its use to improve the technological and functional characteristics of broiler chicken meat with PSE traits. The addition of arabinogalactan to the recipe composition of minced meat during the production of sausages, in an amount of 0.5% of the main raw material, increased the moisture-binding capacity by 5% while reducing losses during heat treatment by 6%. There was an improvement in peroxide and acid numbers during storage, which ensures inhibition of oxidative processes and prevents spoilage of finished products.

Extraction, purification and characterization of an arabinogalactan from frost (riverbank) grape (Vitis riparia Michx.) stems

This study investigated the extraction and properties of an arabinogalactan polysaccharide from frost grape (FGP) as a potential alternative to gum arabic (GA). Collection date, solvent:feed ratio (S:F), chip size, C-18 filtration, ultrafiltration, freeze drying versus spray drying, methanol pre-extraction, and water absorption were examined. Sugar composition, elemental analysis, dietary fiber content, emulsification activity index (EAI), emulsification stability index (ESI), and viscosity were used to evaluate the extracts. Exudates collected in March from live stems were viscous with high percentage solids and FGP, while May collections were watery with low percentage solids and FGP. Frost grape stems were collected, chipped, and classified by size. The extraction system utilized pressure or vacuum to increase contact between the chips and extraction water. A S:F ratio of ca. 24% gave an excellent yield of FGP. Chips between 1.8 and 3.8 mm gave the highest mass yields. Pre-extracting the chips with methanol and C-18 filtration of the water extract both yielded a lighter product. The EAI for the FGP was higher than that for GA; however, its ESI was lower. Ultrafiltration of the crude extract separated glucose, fructose, and sucrose from the FGP. FGP with glucose, fructose, and sucrose adsorbed water and became darker.

ДИЗАЙН НАНОЧАСТИЦ ОКСИДОВ ПЕРЕХОДНЫХ МЕТАЛЛОВ С КОНТРОЛИРУЕМОЙ РАЗМЕРНОСТЬЮ

The paper presents generalized experimental data on the influence of synthesis conditions on the structural features of MeO transition metal oxide nanoparticles in a polymer matrix synthesized by chemical condensation. The synthesis process includes the interaction of aqueous solutions of metal salts of varying concentrations with alkalis in the presence of an aqueous solution of the natural polysaccharide arabinogalactan. Controlled growth of oxide nanoparticles was achieved by encapsulation of emerging NPs in a polysaccharide matrix. The structural properties of the obtained samples were analyzed using X-ray diffraction, IR and UV spectroscopy, and TEM and SEM electron microscopy.

Применение арабиногалактана для минерализации древесины

Formulation and technological solutions aimed at improving the physico-chemical and physico-mechanical characteristics of pine wood construction materials by mineralization of the plant raw materials matrix due to its treatment with an aqueous organomineral suspension based on arabinogalactan and pre-mechanoactivated silica-containing sand have been developed and scientifically substantiated. The natural polysaccharide arabinogalactan isolated from larch wood can act as a stabilizer of aggregation and sedimentation stability of suspension particles for wood processing. Experimental data on the thermal effect calorimetric measurement of the enthalpy of complexation for a series of experimental samples with different contents of a silica-containing component are presented. The results confirming the high efficiency of arabinogalactan as a surfactant have been obtained. The fact of the formation of a chemical bond during the impregnation of wood samples with an organomineral suspension between organic macromolecules (cellulose, lignin, hemicellulose) of vegetable raw materials and silica of the mineral component was found, which contributes to the consolidation of the latter in the structure of the wood matrix. Mineralization of the wood surface with compositions containing arabinogalactan and silica nanoparticles gives an increase in density and hardness, as well as the acquisition of hydrophobic properties and resistance to oxidative degradation. This indicates the possibility of using this composition for petrifying wood. The kinetic description of the complexation process is given, the conditions of stable long-term existence of the complex in an aqueous medium are established. It is shown that the treatment of wood with suspension for 24 hours in a spontaneous mode with a rationally selected composition leads to an increase in the density of vegetable raw materials by 10 %, an increase in strength along the fibers by 80 %, Brinell hardness by 3,4 times. Impregnation of wood samples in autoclave mode with a similar suspension (under an excess pressure of 1,35…1,40 MPa) significantly intensifies the process of mineralization of plant raw materials. Thus, over a time period of 24 hours, the density of wood increases by 70 %, the increase in strength along the fibers was 91 %, Brinell hardness increases by 3,5 times, water absorption decreases by 21 %. It was found that the impregnation of wood with a suspension of the developed organomineral composition does not lead to a change in the geometric dimensions and texture of the samples.

Automated glycan assembly of highly branched heptadecasaccharide repeating unit of arabinogalactan polysaccharide HH1-1 from Carthamus tinctorius.

Polysaccharides that are part of the human diet of fruits and vegetables influence the immune system via multiple signaling pathways. Given the immense complexity and diversity of naturally occurring polysaccharides and the difficulties associated isolating pure samples, few structure-activity relationships have been established. Rapid access to well-defined polysaccharides of biological relevance by automated glycan assembly (AGA) is important to create chemical tools to determine the link between nutritional oligo- and polysaccharides and the immune response. Here, we describe AGA of a hyper branched heptadecasaccharide repeating unit of arabinogalactan polysaccharide HH1-1 from Carthamus tinctorius.

Anti-tuberculosis drug development via targeting the cell envelope of Mycobacterium tuberculosis.

Mycobacterium tuberculosis possesses a dynamic cell envelope, which consists of a peptidoglycan layer, a mycolic acid layer, and an arabinogalactan polysaccharide. This envelope possesses a highly complex and unique structure representing a barrier that protects and assists the growth of M. tuberculosis and allows its adaptation to the host. It regulates the immune response of the host cells, causing their damage. Therefore, the cell envelope of M. tuberculosis is an attractive target for vaccine and drug development. The emergence of multidrug-resistant as well as extensively drug resistant tuberculosis and co-infection with HIV prevented an effective control of this disease. Thus, the discovery and development of new drugs is a major keystone for TB treatment and control. This review mainly summarizes the development of drug enzymes involved in the biosynthesis of the cell wall in M. tuberculosis, and other potential drug targets in this pathway, to provide more effective strategies for the development of new drugs.

ФИЗИКО-МЕХАНИЧЕСКИЕ ХАРАКТЕРИСТИКИ МИНЕРАЛИЗОВАННОЙ ДРЕВЕСИНЫ

A comparative analysis of the mineralization of wood with a solution of an organic mineral complex in various modes is carried out: spontaneous (by immersion in a container with a solution) and forced (during autoclave treatment under excessive pressure using an inert gas) modes. This analysis will reveal the optimal parameters of wood mineralization, which, in turn, will help to solve the problem of increasing the durability and reliability of wood materials intended for use in extreme climatic conditions. The composition of the modifying solution is natural polysaccharide arabinogalactan and polymineral quartz-containing sand (10 % arabinogalactan and 10 % polymineral sand). It is found that during 24 hours of processing, the density of pine wood increases by 18 % (with spontaneous flow of the process, this parameter increases by only&#x0D; 10 %). An increase in the density of samples leads to an increase in their compressive strength by 80 % (during spontaneous processing) and by 91 % (during autoclaving). The Brinell hardness of the prototypes increases more than three times (regardless of the conditions of the process). A detailed description of the individual stages of the process of thermal decomposition of the wood of the prototypes is obtained. It is found that for modified samples (compared with control ones), the degree of thermal destruction is significantly reduced.

Magnetic Composite Coatings FeC and NiC Synthesized With Arabinogalactan

In this work, we investigated the ferromagnetic resonance spectra of metal/carbon composite coatings. FeC and NiC coatings were synthesized by electroless deposition using polysaccharide arabinogalactan. An analysis of the angular dependences of the resonance field showed that the coatings consist of three magnetic phases separated by a nonmagnetic phase of carbon.

Pro-apoptotic, anti-metastatic, and anti-telomerase activity of Tinospora cordifolia and its active polysaccharide arabinogalactan during Benzo(a)pyrene-induced lung carcinogenesis.

BACKGROUND:The present study aims to unravel the pro-apoptotic, anti-metastatic, and anti-telomerase activity of aqueous extract of Tinospora cordifolia stem (Aq.Tc) and its active component arabinogalactan (AG) during Benzo(a)pyrene [B(a)P]-induced lung tumorigenesis in mice.MATERIALS AND METHODS:Lung tumors were induced in male BALB/c mice using B(a)P as a carcinogen. Animals were administered twice with 50 mg/kg b.wt (i.p.) dosage of B(a)P at the 2nd and 4th week of the study. Mice were orally treated with Aq.Tc and AG on alternate days at a dose of 200 mg/kg b.wt and 7.5 mg/kg b.wt, respectively, for continuous 22 weeks.RESULTS:Oral administration of animals with Aq.Tc and AG suppressed the development of lung carcinogenesis by modulating the mRNA and protein expressions of different apoptotic genes; bcl-2, bax, caspase 3, and caspase 9. The pro-apoptotic proficiency of Aq.Tc and AG was further confirmed by DNA agarose gel electrophoresis showing fragmentation in B(a)P + Aq.Tc group and smear formation in B(a)P + AG group. In contrast to the control group, an increase in tumor invasion factors such as matrix metalloproteinases-2 (MMP-2) and MMP-9 was also observed in B(a)P treated animals. Nevertheless, Aq.Tc and AG treatment effectively mitigated the B(a)P-induced upregulation of MMP-2 and MMP-9. The activity of the telomerase enzyme was also observed to be upregulated in B(a)P treated animals which consecutively found to get normalized with the parallel administration of Aq.Tc and AG.CONCLUSION:Aq.Tc and AG successfully mitigated the altered expression of apoptosis, metastasis, and telomerase activity-associated genes during pulmonary carcinogenesis.

Physical and chemical analysis in crude taro mucilage obtained by simple extraction technique

Crude taro mucilage (CM) is considered a product that contains the presence of starch, in addition to other carbohydrates. The use of this mucilage is interesting in the bakery industry, mainly as an emulsifier . The objective of this study was to understand the chemical and physical characteristics of CM to justify its emulsifying action and find other potential applications in the food industry. In the first stage of the work, the raw material (taro rhizome) used for the extraction of mucilage was chemically characterized (moisture, ether extract, crude protein, crude fiber, ashes and glicidic fraction). CM was extracted through a simple method and without the use of chemical reagents, using rhizome crushed, filtration on a polyester mesh and lyophilized. Proximate composition, starch, minerals, monosaccharides, amino acids, infrared spectrum, X-ray diffractometry and thermal property analyses were conducted in the mucilage. CM has thermal stability up to approximately 200 °C and has semi-crystalline structure. Mucilage studied contains arabinogalactan polysaccharide, which can be linked to the protein fraction, according to infrared analysis, forming the arabinogalactan-protein macromolecule, responsible for the emulsifying property. The starch found is considered the main responsible for its thickening action. Moreover, CM can be considered mineral-enriching flour in food products due to the increase of ashes by the mucilage extraction process and the high content of iron micromineral.

Synthesis of the sulfated arabinogalactan tetramethylammonium complex

Sulfated polysaccharides, due to the presence of anionic groups, are able to form complexes with positively charged molecules. This work presents the results of obtaining complexes of the sulfated polysaccharide arabinogalactan with tetramethylammonium bromide. The resulting complex was shown to be soluble in water and methylene chloride. The introduction of tetramethylammonium bromide into the molecule of sulfated arabinogalactan has been proven by elemental analysis and FTIR spectroscopy.

Effect of Arabinogalactan on Intestinal Alkaline Phosphatase, Bacterial Endotoxin and Serum Cytokines in Type 2 Diabetic Rats

In the experiment, a low-dose intraperitoneal injection of streptozotocin (30 mg/kg) was used to establish a diabetic rat model. After the modeling being successful, the mice were continuously administered arabinogalactan aqueous solution (100 mg/kg·d, 500 mg/kg·d), and the changes in rat body mass and blood sugar were determined. Also, the activity of intestinal alkaline phosphatase (IAP) in feces and the changes in bacterial endotoxin lipopolysaccharide (LPS) concentration, and the serum cytokine concentration changes by MSD multi-factor method were detected. The results showed that compared with the model group and the positive control group, the fasting blood glucose concentration of the arabinogalactan polysaccharide dose group was significantly reduced (P<0.05), and the IAP activity was significantly increased (P<0.05). Besides, the LPS concentration was significantly reduced (P<0.05), and the concentration of Interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1 (IL-1β) and growth-regulating oncogene α (KC/GRO) was significantly reduced in the intestine (P<0.05), while the concentration of the anti-inflammatory factors such as interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-10 (IL-10) and interleukin-13 (IL-13) increased significantly (P<0.05). Therefore, it can be proved that arabinogalactan can improve the activity of IAP, reduce the concentration of LPS, and regulate rat cytokines. Furthermore, arabinogalactan has a certain improvement effect on the immunity of type 2 diabetic rat model.

Formation and paramagnetic properties of manganese-containing bionanocomposites based on natural polysaccharide matrices

Synthesis, structural features, and paramagnetic properties of manganese-containing nanocomposites based on polysaccharides arabinogalactan, sulfated arabinogalactan, and κ-carrageenan have been studied. All compounds have been investigated by physical and chemical methods including electron paramagnetic resonance, transmission electron microscopy, infrared spectroscopy, and atomic absorption analysis. It is shown that manganese-containing nanoparticles of 3–6 nm in size were stabilized in the polysaccharide mass by coordination with Mn2+, and the resulting particles have a complex structural organization and are highly EPR active with a spin concentration of about 1020 spin/g. The obtained nanocomposites possess aggregative stability and conserve their properties for a long time.

Three β-Glucuronosyltransferase Genes Involved in Arabinogalactan Biosynthesis Function in Arabidopsis Growth and Development.

Arabinogalactan proteins (AGPs) contain arabinogalactan (AG) polysaccharides that are biologically relevant to plant growth processes. Here, the biochemical and physiological roles of three Golgi localized β-glucuronosyltransferase genes (GLCAT14A, GLCAT14B and GLCAT14C) in Arabidopsis thaliana, responsible for the addition of glucuronic acid to AG chains, were further investigated using single, double and triple glcat14 mutant plants. These proteins were localized to the Golgi apparatus when transiently expressed in Nicotiana benthamiana. Sugar analysis of AGP extracts from Arabidopsis stem, leaf and siliques showed a consistent reduction in glucuronic acid in glcat14 mutants relative to wild type, with concomitant effects resulting in tissue-specific alterations, especially in arabinose and galactose sugars. Although we observed defects in trichome branching in glca14a/b and glca14a/b/c mutants, scanning electron microscope analysis/energy dispersive microanalysis (SEM/EDX) showed no difference in the calcium content of trichomes in these mutants relative to wild type. Immunoblot analyses of the stem and leaf showed a reduction in AGPs as detected with the LM2 antibody in glcat14a/b and glcat14a/b/c mutants relative to wild type. The current work exemplifies the possibility of conducting structure-function assessment of cell wall biosynthetic genes to identify their physiological roles in plant growth and development.

Two \u03b2-glucuronosyltransferases involved in the biosynthesis of type II arabinogalactans function in mucilage polysaccharide matrix organization in Arabidopsis thaliana

BackgroundArabinogalactan-proteins (AGPs) are heavily glycosylated with type II arabinogalactan (AG) polysaccharides attached to hydroxyproline residues in their protein backbone. Type II AGs are necessary for plant growth and critically important for the establishment of normal cellular functions. Despite the importance of type II AGs in plant development, our understanding of the underlying role of these glycans/sugar residues in mucilage formation and seed coat epidermal cell development is poorly understood and far from complete. One such sugar residue is the glucuronic acid residues of AGPs that are transferred onto AGP glycans by the action of β-glucuronosyltransferase genes/enzymes.ResultsHere, we have characterized two β-glucuronosyltransferase genes, GLCAT14A and GLCAT14C, that are involved in the transfer of β-glucuronic acid (GlcA) to type II AGs. Using a reverse genetics approach, we observed that glcat14a-1 mutants displayed subtle alterations in mucilage pectin homogalacturonan (HG) compared to wild type (WT), while glcat14a-1glcat14c-1 mutants displayed much more severe mucilage phenotypes, including loss of adherent mucilage and significant alterations in cellulose ray formation and seed coat morphology. Monosaccharide composition analysis showed significant alterations in the sugar amounts of glcat14a-1glcat14c-1 mutants relative to WT in the adherent and non-adherent seed mucilage. Also, a reduction in total mucilage content was observed in glcat14a-1glcat14c-1 mutants relative to WT. In addition, glcat14a-1glcat14c-1 mutants showed defects in pectin formation, calcium content and the degree of pectin methyl-esterification (DM) as well as reductions in crystalline cellulose content and seed size.ConclusionsThese results raise important questions regarding cell wall polymer interactions and organization during mucilage formation. We propose that the enzymatic activities of GLCAT14A and GLCAT14C play partially redundant roles and are required for the organization of the mucilage matrix and seed size in Arabidopsis thaliana. This work brings us a step closer towards identifying potential gene targets for engineering plant cell walls for industrial applications.

Structural Insight and in vitro Free Radical Scavenging Capacity of Arabinogalactan Polysaccharides from the Peels of Punica granatum

The juice extracted from Punica granatum L. fruit has been used for ages as an important functional food that can endow with healthcare benefits besides fundamental nutritional food that we intake. Although demonstration of antioxidant activity has been shown here, the target molecule responsible for this phenomenon remains unidentified. In this present work, we report a structural insight and antioxidant activity of its polysaccharide (PF-1), purified from water extract (WE) by precipitation with ethanol, ethanol soluble fraction (PF-2) and acetone extracted fraction (PF-3). The purified polysaccharide (PF-1) contains mainly arabinose, galactose together with lesser amount of rhamnose and glucose residues, and the molecular mass was determined 180 kDa. This fraction consists of T-(1,5)- and (1,3,5)-linked Araf; T-(1,6)- and (1,3,6)-linked Galp alongside (1,2,4)-linked Rhap residues. The glucan is found to be β-(1→3)-linked glucopyranosyl residues with a molecular mass of 9 kDa. The in vitro antioxidant activity of the active fractions was determined by using 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), hydroxyl radical scavenging and total antioxidant activity (TAA) assays. The arabinogalactan showed the highest potential among the polysaccharides. This work involves an economically viable simple extraction method and reports promising antioxidant capacity. The studies suggest that this polysaccharide from Punica granatum L. fruit could be a natural antioxidant.