A novel strategy with in vivo characterization, extraction, isolation and activity evaluation for discovery of absorbed anti-inflammatory oligosaccharides from Zhu-Ling decoction.

Zhu-Ling decoction (ZLD), a classical traditional Chinese medicine (TCM) formula, is used for the treatment of chronic kidney diseases. However, the structure and activity of absorbed oligosaccharides (OSs) in ZLD are not clear. In this study, a novel strategy with in vivo characterization, extraction, isolation, activity evaluation was established and applied to identify absorbed anti-inflammatory OSs in ZLD. The results revealed that 30 OSs (22 reducing and 8 non-reducing OSs) and 11 OSs (7 reducing and 4 non-reducing OS) were characterized from ZLD in vitro and in vivo by using UPLC/Q-TOF-MS with PMP derivatization, respectively. Among them, a series of -1 â†’ 3-ß-D-Glcp-OSs were isolated and identified by HPLC-HILIC-UVD-ELSD, SPHPLC-HILIC-RID, monosaccharide composition, MS and 1D/2D-NMR spectroscopy, including laminaritriose, laminaritetraose, laminaripentaose, laminarihexaose, laminariheptaose, laminarioctaose and laminarinonaose. Moreover, the 4 non-reducing absorbed OSs were identified by comparison with reference standards, including sucrose, trehalose, raffinose and stachyose. Among them, laminaritriose, laminaritetraose and laminaripentaose significantly inhibited TNF-α and IL-6 levels in LPS-induced HK-2 cell and exerted significant anti-inflammatory effects via the NF-κB and Akt/mTOR signaling pathways. Together, our work provides a novel strategy for discovery of absorbed anti-inflammatory OSs and broadens new horizons for the discovery of in vivo pharmacodynamic substances in TCM formulas.

Purification and Structural Analyses of Sulfated Polysaccharides from Low-Value Sea Cucumber Stichopus naso and Anticoagulant Activities of Its Oligosaccharides.

Three polysaccharides (SnNG, SnFS and SnFG) were purified from the body wall of Stichopus naso. The physicochemical properties, including monosaccharide composition, molecular weight, sulfate content, and optical rotation, were analyzed, confirming that SnFS and SnFG are sulfated polysaccharides commonly found in sea cucumbers. The highly regular structure {3)-L-Fuc2S-(α1,}n of SnFS was determined via a detailed NMR analysis of its oxidative degradation product. By employing ß-elimination depolymerization of SnFG, tri-, penta-, octa-, hendeca-, tetradeca-, and heptadeca-saccharides were obtained from the low-molecular-weight product. Their well-defined structures confirmed that SnFG possessed the backbone of {D-GalNAc4S6S-ß(1,4)-D-GlcA}, and each GlcA residue was branched with Fuc2S4S. SnFS and SnFG are both structurally the simplest version of natural fucan sulfate and fucosylated glycosaminoglycan, facilitating the application of low-value sea cucumbers S. naso. Bioactivity assays showed that SnFG and its derived oligosaccharides exhibited potent anticoagulation and intrinsic factor Xase (iXase) inhibition. Moreover, a comparative analysis with the series of oligosaccharides solely branched with Fuc3S4S showed that in oligosaccharides with lower degrees of polymerization, such as octasaccharides, Fuc2S4S led to a greater increase in APTT prolongation and iXase inhibition. As the degree of polymerization increases, the influence from the sulfation pattern diminishes, until it is overshadowed by the effects of molecular weight.

Isolation and characterization of feruloylated oligosaccharides from Phyllostachys acuta and in vitro antioxidant activity.

Feruloylated oligosaccharides (FOs) generated by decomposing plant hemicellulose, offer a wide range of potential applications in both the food and biomedical areas. As a graminaceous plant, bamboo is rich in hemicellulose. However, the structural composition and activity studies of FOs from it were rarely reported. In this study, FOs from Phyllostachys acuta (pFOs) obtained by enzymatic hydrolysis were isolated by AmberliteXAD-2 and C18 SPE columns. Then, pFOs were qualitatively and quantitatively analyzed by UPLC-ESI-MS/MS after labeled by 3-Amino-9-ethyl-carbazole (AEC), and the chemical antioxidant activity of pFOs and effects of pFOs on H2O2-induced oxidative damage were investigated. Finally, 14 of pFOs isomers were distinguished and identified, of which 10 did not contain hexoses and 4 did, and the three most abundant pFO structures were 12 (Iso 7, F1A1X2H2-AEC, 29.04 %), 11 (Iso 6, F1A1X1H2-AEC, 17.96 %), and 4 (Iso 3-1, F1A1X3-AEC, 15.57 %). The results of antioxidant studies showed that pFOs possessed certain reducing power, scavenging DPPH radicals, scavenging superoxide anion radicals, and scavenging hydroxyl radicals. Among them, the ability to clear DPPH radicals was particularly significant. pFOs significantly reduced the viability of RAW264.7 cells after H2O2 induction, whereas pFOs had a significant protective effect (p < 0.001). pFOs increased the viability of T-AOC and SOD enzymes in oxidatively damaged cells, as well as had a significant inhibition effect on ROS elevation (p < 0.001). This study lays the foundation for the structural analysis and antioxidant activity evaluation of bamboo-derived feruloyl oligosaccharides for their application in food and pharmaceutical fields.

Isolation of Human Milk Difucosyl Nona- and Decasaccharides by Ultrahigh-Temperature Preparative PGC-HPLC and Identification of Novel Difucosylated Heptaose and Octaose Backbones by Negative-Ion ESI-MSn.

Despite their many important physiological functions, past work on the diverse sequences of human milk oligosaccharides (HMOs) has been focused mainly on the highly abundant HMOs with a relatively low degree of polymerization (DP) due to the lack of efficient methods for separation/purification and high-sensitivity sequencing of large-sized HMOs with DP ≥ 10. Here we established an ultrahigh-temperature preparative HPLC based on a porous graphitized carbon column at up to 145 °C to overcome the anomeric α/ß splitting problem and developed further the negative-ion ESI-CID-MS/MS into multistage MSn using a combined product-ion scanning of singly charged molecular ion and doubly charged fragment ion of the branching Gal and adjacent GlcNAc residues. The separation and sequencing method allows efficient separation of a neutral fraction with DP ≥ 10 into 70 components, among which 17 isomeric difucosylated nona- and decasaccharides were further purified and sequenced. As a result, novel branched difucosyl heptaose and octaose backbones were unambiguously identified in addition to the conventional linear and branched octaose backbones. The novel structures of difucosylated DF-novo-heptaose, DF-novo-LNO I, and DF-novo-LNnO I were corroborated by NMR. The various fucose-containing Lewis epitopes identified on different backbones were confirmed by oligosaccharide microarray analysis.

Structural characterization and therapeutic effect of Alhagi honey oligosaccharide on liver fibrosis in mice.

Alhagi honey is derived from the secretory granules of Alhagi pseudoalhagi Desv., a leguminous plant commonly known as camelthorn. Modern medical research has demonstrated that the extract of Alhagi honey possesses regulatory properties for the gastrointestinal tract and immune system, as well as exerts anti-tumor, anti-oxidative, anti-inflammatory, anti-bacterial, and hepatoprotective effects. The aim of this study was to isolate and purify oligosaccharide monomers (referred to as Mel) from camelthorn and elucidate their structural characteristics. Subsequently, the impact of Mel on liver injury induced by carbon tetrachloride (CCl4) in mice was investigated. The analysis identified the isolated oligosaccharide monomer (α-D-Glcp-(1 â†’ 3)-ß-D-Fruf-(2 â†’ 1)-α-D-Glcp), with the molecular formula C18H32O16. In a mouse model of CCl4-induced liver fibrosis, Mel demonstrated significant therapeutic effects by attenuating the development of fibrosis. Moreover, it enhanced anti-oxidant enzyme activity (glutathione peroxidase and superoxide dismutase) in liver tissues, thereby reducing oxidative stress markers (malondialdehyde and reactive oxygen species). Mel also improved serum albumin levels, lowered liver enzyme activities (aspartate aminotransferase and alanine aminotransferase), and decreased inflammatory factors (tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-6). Immunohistochemistry, immunofluorescence, and western blotting analyses confirmed the ability of Mel to downregulate hepatic stellate cell-specific markers (collagen type I alpha 1 chain, alpha-smooth muscle actin, transforming growth factor-beta 1. Non-targeted metabolomics analysis revealed the influence of Mel on metabolic pathways related to glutathione, niacin, pyrimidine, butyric acid, and amino acids. In conclusion, the results of our study highlight the promising potential of Mel, derived from Alhagi honey, as a viable candidate drug for treating liver fibrosis. This discovery offers a potentially advantageous option for individuals seeking natural and effective means to promote liver health.

Ameliorative Effect of Morinda Officinalis Oligosaccharides on LPS-Induced Acute Lung Injury.

Acute lung injury (ALI) is a disease characterized by extensive lung damage and rampant inflammation, with a high mortality rate and no effective treatments available. Morinda officinalis oligosaccharides (MOOs), derived from the root of the traditional Chinese medicinal herb Morinda officinalis, known for its immune-boosting properties, presents a novel therapeutic possibility. To date, the impact of MOOs on ALI has not been explored. Our study aimed to investigate the potential protective effects of MOOs against ALI and to uncover the underlying mechanisms through an integrated approach of network pharmacology, molecular docking, and experimental validation. We discovered that MOOs significantly mitigated the pathological damage and decreased the expression of pro-inflammatory cytokines in LPS-induced ALI in mice. Complementary in vitro studies further demonstrated that MOOs effectively attenuated the M1 polarization induced by LPS. Network pharmacology analysis identified HSP90AA1, HSP90AB1, and NF-κB as key overlapping targets within a protein-protein interaction (PPI) network. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses elucidated the biological processes and signaling pathways implicated in MOOs' therapeutic action on ALI. Subsequently, molecular docking affirmed the binding of MOOs to the active sites of these identified targets. Corroborating these findings, our in vivo and in vitro experiments consistently demonstrated that MOOs significantly inhibited the LPS-induced upregulation of HSP90 and NF-κB. Collectively, these findings suggest that MOOs confer protection against ALI through a multi-target, multi-pathway mechanism, offering a promising new therapeutic strategy to mitigate this severe pulmonary condition.

Sulphated Fucooligosaccharide from Sargassum Horneri: Structural Analysis and Anti-Alzheimer Activity.

In the present study, sulfated polysaccharides were obtained by digestion of Sargassum horneri and preparation with enzyme-assisted extraction using three food-grade enzymes, and their anti- Alzheimer's activities were investigated. The results demonstrated that the crude sulfated polysaccharides extracted using AMGSP, CSP and VSP dose-dependently (25-100 µg·mL- 1) raised the spontaneous alternating manner (%) in the Y maze experiment of mice and reduced the escape latency time in Morris maze test. AMGSP, CSP and VSP also exhibited good anti-AChE and moderate anti-BuChE activities. CSP displayed the best inhibitory efficacy against AChE. with IC50 values of 9.77 µM. And, CSP also exhibited good inhibitory selectivity of AChE over BuChE. Next, CSP of the best active crude extract was separated by the preparation type high performance liquid phase to obtain the sulphated fucooligosaccharide section: SFcup (→3-α-L-fucp(2-SO3-)-1→4-α-L-fucp(2,3-SO3-)-1→section), SFcup showed a best inhibitory efficacy against AChE with IC50 values of 4.03 µM. The kinetic research showed that SFcup inhibited AChE through dual binding sites. Moreover, the molecular docking of SFcup at the AChE active site was in accordance with the acquired pharmacological results.

Chemical Fingerprint Analysis and Quantitative Analysis of Saccharides in Morindae Officinalis Radix by HPLC-ELSD.

A method based on high performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD) was developed for the quantitative analysis of three active compounds and chemical fingerprint analyses of saccharides in Morindae officinalis radix. Ten batches of Morindae officinalis radix were collected from different plantations in the Guangdong region of China and used to establish the fingerprint. The samples were separated with a COSMOIL Sugar-D column (4.6 mm × 250 mm, 5 µm) by using gradient elution with water (A) and acetonitrile (B). In addition, Trapped-Ion-Mobility (tims) Time-Of-Flight (tims TOF) was used to identify saccharides of Morindae officinalis radix. Fingerprint chromatogram presented 26 common characteristic peaks in the roots of Morinda officinalis How, and the similarities were more than 0.926. In quantitative analysis, the three compounds showed good regression (r = 0.9995-0.9998) within the test ranges, and the recoveries of the method were in the range of 96.7-101.7%. The contents of sucrose, kestose and nystose in all samples were determined as 1.21-7.92%, 1.02-3.37%, and 2.38-6.55%, respectively. The developed HPLC fingerprint method is reliable and was validated for the quality control and identification of Morindae officinalis radix and can be successfully used to assess the quality of Morindae officinalis radix.

Pressurized Hot Water Extraction and Bio-Hydrogels Formulation with Aristotelia chilensis [Mol.] Stuntz Leaves.

Aristotelia chilensis is a plant rich in phenolics and other bioactive compounds. Their leaves are discarded as waste in the maqui berry industry. A new application of these wastes is intended by the recovery of bioactive compounds using pressurized hot water extraction with conventional or microwave heating. Both technologies have been selected for their green character regarding the type of solvent and the high efficiency in shorter operation times. Extractions were performed in the temperature range 140-200 °C with a solid/liquid ratio of 1:15 (w:w). The extracts' total phenolic content, antioxidant capacity, and saccharides content obtained with both heating methods were measured. Additionally, the thermo-rheological properties of the gelling matrix enriched with these extracts were analyzed. Optimum conditions for lyophilized extracts were found with conventional heating, at 140 °C and 20 min extraction; 250.0 mg GAE/g dry extract and 1321.5 mg Trolox/g dry extract. Close to optimum performance was achieved with microwave heating in a fraction of the time (5 min) at 160 °C (extraction), yielding extracts with 231.9 mg GAE/g dry extract of total phenolics and antiradical capacity equivalent to 1176.3 mg Trolox/g dry extract. Slightly higher antioxidant values were identified for spray-dried extracts (between 5% for phenolic content and 2.5% for antioxidant capacity). The extracts obtained with both heating methods at 200 °C contained more than 20% oligosaccharides, primarily glucose. All the formulated gelling matrices enriched with the obtained extracts displayed intermediate gel strength properties. The tested technologies efficiently recovered highly active antioxidant extracts, rich in polyphenolics, and valuable for formulating gelling matrices with potential applicability in foods and other products.

An improved method for galactosyl oligosaccharide characterization.

Due to beneficial effects of galactosyl oligosaccharides (GOS) on digestive and immune health, their characterization has become increasingly important. This is especially so as GOS are synthesized enzymatically and contain oligosaccharides of different sizes and linkages. High performance anion exchange chromatography with pulsed amperometric detection (HPAE-PAD) is widely used for GOS characterization. With its high resolving power, it can separate structural isomers. Here we present a significant improvement to currently used methods. Our approach combines high resolution HPAE separation on a CarboPac PA300 column with 4 µm particle size with PAD and Orbitrap mass spectrometry (MS) detections to provide in-depth information on GOS composition. Oligosaccharide resolution, especially in the disaccharide region, is significantly improved and can be routinely achieved. Improvement in technology to remove sodium before MS results in minimal peak dispersion, allowing GOS degrees of polymerization 2 to 6 to be identified based on mass spectra obtained from intact oligosaccharides and confirmed using fragmentation patterns observed in MS/MS data. Combining HPAE with MS led to identification of 28 oligosaccharides in a commercial GOS sample. We attempted to correlate oligosaccharide structure with observed elution behavior. To our knowledge this is first such attempt and can form a basis for a comprehensive structure vs HPAE elution behavior database.

Enzymatic extraction of pectic oligosaccharides from finger citron (Citrus medica L. var. sarcodactylis Swingle) pomace with antioxidant potential.

Finger citron pomace is a cheap and renewable by-product of the citrus processing industry, representing up to 60% of the fruit biomass. In this study, a pectinase-based and ultrasonic-assisted method was firstly used to extract pectic oligosaccharides (POS) from finger citron pomace. Using the orthogonal experiment design (OED), the maximum conversion rate of up to 64.5% from pomace to POS was obtained under the extraction conditions of 0.25 mg mL-1 pectinase and 50 mg mL-1 pectin at 45 °C and pH 4.5 for 2 h. The extracted POS was then fractionated and purified to homogeneous oligosaccharides (FCPOS-1) with a molecular weight of 2.15 kDa, and the analyses of monosaccharide composition, FTIR, NMR and ESI-MS indicated that FCPOS-1 consisted of GalA and a small amount of mannose, galactose and arabinose. Multiple antioxidant activity assays in vitro revealed that FCPOS-1 possessed remarkable antioxidant properties, especially scavenging activity against DPPH radicals up to 94.07%. FCPOS-1 has the potential to be an effective natural antioxidant for applications in the food and pharmaceutical industries.

High level expression of a xyloglucanase from Rhizomucor miehei in Pichia pastoris for production of xyloglucan oligosaccharides and its application in yoghurt.

The xyloglucanase gene (RmXEG12A) from Rhizomucor miehei CAU432 was successfully expressed in Pichia pastoris. The highest xyloglucanase activity of 25,700 U mL-1 was secreted using high cell density fermentation. RmXEG12A was optimally active at pH 7.0 and 65 °C, respectively. The xyloglucanase exhibited the highest specific activity towards xyloglucan (7915.5 U mg-1). RmXEG12A was subjected to hydrolyze tamarind powder to produce xyloglucan oligosaccharides with the degree of polymerization (DP) 7-9. The hydrolysis ratio of xyloglucan in tamarind powder was 89.8%. Moreover, xyloglucan oligosaccharides (2.0%, w/w) improved the water holding capacity (WHC) of yoghurt by 1.1-fold and promoted the growth of Lactobacillus bulgaricus and Streptococcus thermophiles by 2.3 and 1.6-fold, respectively. Therefore, a suitable xyloglucanase for tamarind powder hydrolysis was expressed in P. pastoris at high level and xyloglucan oligosaccharides improved the quality of yoghurt.

A method for quantitative characterization of incomplete degradation products of polygalacturonic acid.

Biological activity of incomplete degradation products of polygalacturonic acid (IDPP) is closely related to its molecular weight and molecular weight distribution. Therefore, it is necessary to provide a reliable quantitative characterization method for evaluating these types of bioproducts. A novel method was established in this work for the quantitative characterization of IDPP based upon ethanol fractional precipitation. IDPP was fractionated into several fractions with high recovery (>95%), and the average molecular weights of each fraction was in descending order with the increase of ethanol concentration. Oligosaccharides (polymerization degree: 2-20) could be effectively harvested from the polygalacturonic acid enzymatic hydrolysate by ethanol precipitation. Moreover, the developed method had good repeatability and could also be applied to quantify enzymatic hydrolysis products of citrus-derived pectin polysaccharides. In conclusion, this paper provides a simple, accurate method for the quantitative characterization of IDPP and a strategy for the extraction of oligosaccharides.

Microbial Oligosaccharides with Biomedical Applications.

Microbial oligosaccharides have been regarded as one of the most appealing natural products attributable to their potent and selective bioactivities, such as antimicrobial activity, inhibition of α-glucosidases and lipase, interference of cellular recognition and signal transduction, and disruption of cell wall biosynthesis. Accordingly, a handful of bioactive oligosaccharides have been developed for the treatment of bacterial infections and type II diabetes mellitus. Given that naturally occurring oligosaccharides have increasingly gained recognition in recent years, a comprehensive review is needed. The current review highlights the chemical structures, biological activities and divergent biosynthetic origins of three subgroups of oligomers including the acarviosine-containing oligosaccharides, saccharomicins, and orthosomycins.

Alginate derived functional oligosaccharides: Recent developments, barriers, and future outlooks.

Alginate is a biopolymer used extensively in the food, pharmaceutical, and chemical industries. Alginate oligosaccharides (AOS) derived from alginate exhibit superior biological activities and therapeutic potential. Alginate lyases with characteristic substrate specificity can facilitate the production of a broad array of AOS with precise structure and functionality. By adopting innovative analytical tools in conjunction with focused clinical studies, the structure-bioactivity relationship of a number of AOS has been brought to light. This review covers fundamental aspects and recent developments in AOS research. Enzymatic and microbial processes involved in AOS production from brown algae and sequential steps involved in AOS structure elucidation are outlined. Biological mechanisms underlying the health benefits of AOS and their potential industrial and therapeutic applications are elaborated. Withal, various challenges in AOS research are traced out, and future directions, specifically on recombinant systems for AOS preparation, are delineated to further widen the horizon of these exceptional oligosaccharides.

Separation of labeled isomeric oligosaccharides by hydrophilic interaction liquid chromatography - the role of organic solvent in manipulating separation selectivity of the amide stationary phase.

The advantages of using mixtures of organic solvents for the separation of labeled oligosaccharides on the amide stationary phase under hydrophilic interaction liquid chromatography conditions are presented. The effect of the type of buffer as well as solvent or their mixtures on retention of uracil, saccharide labeling reagents (2-aminobenzoic acid, 2-aminobenzamide, ethyl 4-aminobenzoate, procainamide), and corresponding labeled saccharides were evaluated. The successful isocratic separation of labeled isomeric trisaccharides (maltotriose, panose, and isomaltotriose) was achieved in the mobile phase consisting of a 90% (v/v) mixture of organic solvents (methanol/acetonitrile 60:40) and 10% (v/v) 30 mM ammonium formate, pH 3.3. Changing the volume ratio between methanol/acetonitrile from 60:40 to 50:50 (v/v) allowed to obtain the separation of di-, tri-, and tetrasaccharides labeled by ethyl 4-aminobenzoate in less than 10.5 min.

Azo-Dyes-Grafted Oligosaccharides-From Synthesis to Applications.

Azobenzenes are photochromic molecules that possess a large range of applications. Their syntheses are usually simple and fast, and their purifications can be easy to perform. Oligosaccharide is also a wide family of biopolymer constituted of linear chain of saccharides. It can be extracted from biomass, as for cellulose, being the principal constituent of plant cell wall, or it can be enzymatically produced as for cyclodextrins, having properties not far from cellulose. Combining these two materials families can afford interesting applications such as controlled drug-release systems, photochromic liquid crystals, photoresponsive films or even fluorescent indicators. This review will compile the different syntheses of azo-dyes-grafted oligosaccharides, and will show their various applications.

Optimization and comparison of the production of galactooligosaccharides using free or immobilized Aspergillus oryzae ß-galactosidase, followed by purification using silica gel.

The aim of this study was to optimize and compare the production of galactooligosaccharides (GOSs) by free and cotton cloth-immobilized Aspergillus oryzae ß-galactosidase, and perform economical evaluation of production of GOSs (100%) between them. Using the response surface method, the optimal reaction time (3.9 h), initial lactose concentration (57.13%), and enzyme to lactose ratio (44.81 U/g) were obtained for the free enzyme, which provided a GOSs yield of 32.62%. For the immobilized enzyme, the optimal yield of GOSs (32.48%) was obtained under reaction time (3.09 h), initial lactose concentration (52.74%), and temperature (50.0 ℃). And it showed desirable reusability during five successive enzymatic reactions. The recovery rate of GOSs (100%) is 65% using silica gel filtration chromatography. The economical evaluation showed almost no difference in the manufacturing cost for the GOSs (100%) between these two systems, and that the recovery rate had a great impact on the cost.

Optimization of ß-1,4-Endoxylanase Production by an Aspergillus niger Strain Growing on Wheat Straw and Application in Xylooligosaccharides Production.

Plant biomass constitutes the main source of renewable carbon on the planet. Its valorization has traditionally been focused on the use of cellulose, although hemicellulose is the second most abundant group of polysaccharides on Earth. The main enzymes involved in plant biomass degradation are glycosyl hydrolases, and filamentous fungi are good producers of these enzymes. In this study, a new strain of Aspergillus niger was used for hemicellulase production under solid-state fermentation using wheat straw as single-carbon source. Physicochemical parameters for the production of an endoxylanase were optimized by using a One-Factor-at-a-Time (OFAT) approach and response surface methodology (RSM). Maximum xylanase yield after RSM optimization was increased 3-fold, and 1.41- fold purification was achieved after ultrafiltration and ion-exchange chromatography, with about 6.2% yield. The highest activity of the purified xylanase was observed at 50 °C and pH 6. The enzyme displayed high thermal and pH stability, with more than 90% residual activity between pH 3.0-9.0 and between 30-40 °C, after 24 h of incubation, with half-lives of 30 min at 50 and 60 °C. The enzyme was mostly active against wheat arabinoxylan, and its kinetic parameters were analyzed (Km = 26.06 mg·mL-1 and Vmax = 5.647 U·mg-1). Wheat straw xylan hydrolysis with the purified ß-1,4 endoxylanase showed that it was able to release xylooligosaccharides, making it suitable for different applications in food technology.

Valorisation of walnut shell and pea pod as novel sources for the production of xylooligosaccharides.

According to the high interest in agro-industrial waste reutilisation, underutilised lignocellulosic materials, such as walnut shell (WS) and pea pod (PP), come in focus. The aim of this paper was to evaluate WS and PP as sources for the production of xylooligosaccharides (XOS). Hemicelluloses from WS and PP were recovered by combining varying parameters of delignification and alkaline extraction. At optimal recovery conditions, the fractions were further hydrolysed to XOS using GH11 endo-xylanase, by varying time and enzyme concentration. Xylose was predominant in the monomeric composition of the obtained hemicelluloses, building low-branched (arabino)glucuronoxylan, in WS exclusively, while in PP some xyloglucan as well. Delignification was essential for high recovery of total xylose from the materials, up to at least 70 %. High xylan conversions were obtained for 24 h hydrolysis, resulting in xylobiose and xylotriose when using low enzyme concentration, while in xylose and xylobiose with high enzyme concentration.