Exploring the potential of selective oxidation in bioconjugation of collagen with xyloglucan carboxylates.

Xyloglucan (XG), as a natural biopolymer, possesses a sound biocompatibility and an impressive biodegradability, which are usually featured with abundant hydroxyl groups available for the bioconjugation with a bioactive moiety, suggesting a promising or unique value possibly applied in the field of biomedicine. In this study, XG was extracted from Tamarind seeds and subjected to four regioselective oxidation methods to introduce carboxyl groups onto the XG molecules for a bioconjugation with collagen. Galactose oxidase and reducing end aldehyde group oxidation mainly resulted in a low carboxylate content at ∼0.34 mmol/g, whereas the primary and secondary hydroxyl group oxidations would lead to a high carboxyl content at ∼0.84 mmol/g. The number-average molar mass (Mn) and weight-average molar mass (Mw) of XG were 8.8 × 105 g/mol and 1.1 × 106 g/mol, respectively. The oxidized XGs were then subjected to a further biofunctionalization with the collagen through EDC/NHS coupling, which exhibited a degree of conjugation rate, ranged from 50 % to 72 %. The collagen-conjugated at the C6 position of XGs exhibited the highest cell viability recorded at 168 % in promoting cell growth and proliferation after 72 h of culture, surpassing that of pure collagen recorded at 138 %, which may indeed suggest a promising value in a biomedical application.

Effects of Heating Temperature on the Properties of Bio-Board Manufactured by Using Soybean Straw.

The objective of this paper is to effectively use soybean straw biomass resources and decrease the negative effects of using synthetic resin. Soybean straw was ground through a wet process then hot-pressed to make biodegradable fiberboard (bio-board) without any binder. The effect of heating temperature on mechanical properties and dimensional stability performance of produced bio-board was investigated. Bonding quality and chemical changes of the bio-board were also evaluated using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The moisture content decreased from 12.5% to 3.4% with the increase of heating temperature. Meanwhile, most mechanical properties of bio-board improved. However, an excessive heating temperature, especially at 230 °C, did not significantly promote the improvement of most mechanical properties. However, the dimensional stability performance of the bio-board was greatly improved from 140 °C to 230 °C. Overall, the results showed that bio-board could be made by using soybean straw without any synthetic resin. Heating temperature plays a significant role in affecting the properties of bio-board. The refined bio-board is expected to be used as a packaging material, heat insulation in architecture, and mulch film for agricultural purposes.