XYLAN

• CAS: 9014-63-5
• Catalog Number: ACM9014635-5
• Category: Main Products
• Molecular Weight: 150.12
• Molecular Formula: C5H10O5
• Description: Off-white, yellow or light-brown powder
• Synonyms: POLY[BETA-D-XYLOPYRANOSE(1->4)];XYLAN;XYLAN EX BEECHWOOD;XYLAN, OAT SPELTS;XYLAN OATS SPELT;(1,4-beta-D-Xylan)n;(1,4-beta-D-Xylan)n+1;1,4-beta-D-Xylan
• Melting Point: 198 °C
• Solubility: 1 M NaOH: may be turbid
• Appearance: Solid
• Application: Xylan is a major constituent of the secondary cell wall and plant cell-wall polysaccharides. Xylan is also used in the studies involving structural properties, foaming as a new means for food structuring in plants. Xylanases an enzymatic form of xylan is used in several biotechnological processes, primarily for biopulping and biobleaching in the paper industry and as accessory enzymes for bioethanol production.
• EC Number: 232-760-6
• MDL Number: MFCD00082148
• Stability: Stable. Incompatible with strong oxidizing agents.
• Storage Temperature: Room Temperature

Case Study

Preparation and Optimization of Properties of Polyvinyl Alcohol/Xylan Composite Films

Chen, Xiao-feng, et al. Journal of Nanomaterials 2015.1 (2015): 810464.

Biodegradable composite films were produced from poly(vinyl alcohol) (PVA) and xylan with glycerol and ammonium zirconium carbonate (AZC) mixed in. The study examined how AZC influenced PVA/xylan films' mechanical properties, water resistance profile, thermal stability level, solubility characteristics, and water vapor permeability.
Preparation Methodology
The films were prepared through a solution casting technique, maintaining a 3:1 weight ratio of PVA to xylan. Started by dissolving 1.5 grams of PVA into 90 mL ultrapure water maintained at 95°C for one hour while stirring to ensure a homogeneous solution. Subsequently, 0.5 g of xylan and 10% glycerol dissolved in 5 mL of ultrapure water were added at 80°C, with stirring for an additional hour. Varying amounts of AZC, ranging from 0% to 15%, were then dissolved in 5 mL of ultrapure water and integrated into the mixture. The final solution was held at 80°C for 5 hours, filtered, and the resulting filtrate was cast into a Teflon mold. Water was gradually evaporated in a ventilated oven at 40°C overnight.
Key Findings
The composite films demonstrated substantial improvements in water resistance and mechanical properties after AZC addition which was especially noticeable in their elongation at break (EAB) performance. As the AZC concentration increased from 0% to 15%, EAB surged from 18.5% to 218.0%, while solubility (S) decreased from 11.64% to 8.64%. Even with 15% AZC, the tensile strength remained commendable at 22.10 MPa. Notably, excellent compatibility among the film components was observed.

Xylan-Based Temperature/pH-Sensitive Hydrogels for Controlled Drug Release

Gao, Cundian, et al. Carbohydrate polymers 151 (2016): 189-197.

Researchers synthesized xylan-based temperature and pH-sensitive hydrogels through crosslinking copolymerization of xylan with N-isopropylacrylamide (NIPAm) and acrylic acid (AA). The crosslinker in the process was N,N'-methylenebisacrylamide (MBA) while 2,2-dimethoxy-2-phenylacetophenone served as the photoinitiator during ultraviolet irradiation. The newly formed hydrogels achieved 97.60% drug encapsulation efficiency while releasing 90.12% of acetylsalicylic acid in intestinal fluid and 26.35% in gastric fluid.
Preparation of Xylan-based P(NIPAm-co-AA) Hydrogels
The preparation of the xylan hydrogel started by dissolving 0.5 grams of xylan in distilled water with a weight percentage of 5% at 85°C for half an hour while stirring with a magnetic stirrer. The mixture dropped to 50°C before incorporating monomers NIPAm and AA along with crosslinker MBA. The mixture underwent a nitrogen purge for 15 minutes. Pre-dissolved DMPA at 2.5% w/w concentration in NMP was added next as the photoinitiator to reach 5% w/w of dried xylan.
A homogeneous solution underwent UV irradiation at 365 nm and 40 W for 6 hours inside a Teflon mould at room temperature and the sealed samples remained there for another 12 hours to finalize polymerization and crosslinking.
After removal from the mould, hydrogels underwent an extensive washing process for five days using deionized water where the bath was changed six times each day to remove impurities and leftover chemicals that did not react. The purified hydrogels were sectioned into sections measuring 8 mm by 8 mm by 2 mm and then subjected to drying through either vacuum oven, refrigerator freeze-drying and liquid nitrogen freeze-drying methods.

Xylan-Chitosan Composite Hydrogel for Bone Tissue Regeneration

Bush, Joshua R., et al. Polymers for Advanced Technologies 27.8 (2016): 1050-1055.

Xylan which possesses immunomodulatory properties has been merged with chitosan to develop a composite hydrogel designed to improve healing of bone fractures. The injectable hydrogel remains liquid at room temperature and turns into a gel when exposed to body temperature which enhances tissue reactions in animal tests compared to standard chitosan hydrogels. Research demonstrates that the xylan/chitosan composite hydrogel functions successfully as a bone graft alternative for repairing substantial bone injuries.
Hydrogel Preparation
First dissolve xylan into 5 ml of filtered, deionized water before adding acetic acid to create a 0.25% v/v solution for the xylan/chitosan composite hydrogel. The preparation process involved incorporating chitosan into the solution and letting it dissolve throughout the night. The ratio of chitosan to xylan was set at 3:1. The hydrogel mixture received an addition of 0.08 g total polymer mass to 5 ml of water. The stable hydrogel formation reaches its maximum potential with this proportion of xylan. The gelation process started when added 23 μl of 4.5 M ammonium hydrogen phosphate solution per milliliter of the liquid polymer mixture.
Performance
The composite hydrogel showed rapid integration with host tissue in subcutaneous implantation models during the first week compared to pure chitosan hydrogels. The composite produced significant bone remodeling at the fracture site within four weeks when tested with mice in a tibia fracture model. The composite hydrogel facilitated bone regeneration and healing of non-union fracture model in rat femurs which would otherwise remain unhealed after six weeks without treatment.

Citric Acid Modified Polyvinyl Alcohol/Xylan Composite Film for Biodegradable Packaging Materials

Wang, Shuaiyang, et al. Carbohydrate polymers 103 (2014): 94-99.

The research applied citric acid as a unique plasticizer and cross-linking agent to develop a composite film from xylan and polyvinyl alcohol (PVA) while examining how citric acid concentration and PVA/xylan mass ratio affected film characteristics.
Preparation of PVA/Xylan Composite Films
Films were prepared by solution casting. First, a measured weight of PVA was stirred in water for 30 min at room temperature, then dissolved completely in a 95°C oil bath for 1 h. Subsequently, xylan and CA were added to the hot PVA solution at 95°C and stirred for 30 min. The mixture was maintained at 75°C for 4 h, then poured into a Teflon mould. Water was evaporated overnight in a ventilated oven at 50°C. CA content (0-50% of total PVA/xylan solids) yielded non-crosslinked films. Crosslinked films were obtained by heating these non-crosslinked films at 110°C for 2.5 h.
Performance
The PVA/xylan composite films demonstrated good compatibility. The tensile strength of the composite films reduced from 35.1 MPa to 11.6 MPa as the citric acid content rose from 10% to 50%, during which elongation at break increased from 15.1% to 249.5%. Water vapor permeability values ranged from 2.35 to 2.95 × 10^-7 g/(mm² h). Stronger interactions between xylan and PVA in the presence of citric acid were observed, attributed to the formation of hydrogen and ester bonds during the film formation process.