Controllably Adjusting the Hydrophobicity of Collagen Fibers for Enhancing the Adsorption Rate, Retention Capacity, and Separation Performance of Flavonoid Aglycones

Collagen fibers (CFs) were previously used as packing materials for the separation of flavonoids based on hydrogen bond and hydrophobic interactions. However, as for flavonoid aglycones, CFs presented unsatisfactory adsorption capacity and separation efficiency due to the fact that they include limited hydroxyls and phenyls. In order to improve the adsorption capacity and separation efficiency, the hydrophobic modification strategy was employed in this research to enhance the hydrophobic interaction of CF with flavonoid aglycones by using silane coupling agents with different alkyl chains (isobutyl, octyl, and dodecyl). FT-IR analysis, DSC, TG, SEM, EDS mapping, water contact angle, and absorption time of solvent proved the successful grafting of alkyl chains on the CF without disturbing its special fiber structure, leading to the significantly enhanced hydrophobicity of the CF. The dynamic adsorption and elution behavior of kaempferol and quercetin (the typical flavonoid aglycones) on the hydrophobic CF showed that the adsorption rate and retention rate were largely increased in comparison with the CF without modification. Molecular dynamic simulations indicated that the CF grafted with isobutyls could interact with flavonoid aglycones through the highest synergetic effect of hydrophobic and hydrogen bond interactions, which exhibited the strongest retention to flavonoid aglycones. On further increasing the alkyl length (octyl and dodecyl), the hydrophobic interaction was further enhanced, but the hydrogen bonds were significantly weakened by steric hindrance, which showed that the retention to flavonoid aglycones was appropriately increased but without causing peak tailing. In the column separation of kaempferol and quercetin, the CF with hydrophobic modification presented a greater separation efficiency, with the purity of kaempferol increased from 71.99 to 86.57-97.50% and the purity of quercetin increased from 82.69 to 88.07-99.37%, which was much better than that of polyamide and close to that of sephadex LH 20. Therefore, the hydrophobicity of the CF could be controllably adjusted to enhance the adsorption rate and retention capacity, specifically improving the separation efficiency of flavonoid aglycones.

Recent advances in the construction of biocomposites based on fungal mycelia

In recent years, environmental problems have become increasingly serious, significantly effecting the ecosystem and human health. To deal with the problem of environmental pollution in an eco-conscious way, sustainable composite biomaterials are being produced. Mycelium-based composite biomaterials combine biological systems with substrates such as nanomaterials or agricultural and industrial wastes, which can complement each other's advantages or turn waste into a useful resource. Such materials can solve practical wastewater problems as well as replace plastic products, thus reducing plastic pollution and contributing to the green transition of the environment. In this review, we summarized the recent findings of studies on these materials, indicating future research directions.

[Preparation of a Nutritional Slow-release Packing Material with Function Microorganisms and Its Characteristics Evaluation]

A nutritional slow-release packing material with function microorganisms (SC) was prepared using emulsification and the cross-linked method. Its potential as packing material in biotrickling filters (BTF) for butyl acetate removal was evaluated. The physicochemical properties show that the packing has a porosity of 92.6%, bulk density of 40.75 kg·m^-3, surface area of 2.45 m²·g^-1, and real density of 551.52 kg·m^-3. The packing material contains hydrophilic groups (O-H, C O) on its surface and nutrient elements (N, P), which are distributed uniformly, with release rates of 22.35 and 8.36 mg·(L·d)^-1, respectively. The biomass concentration of the packing (protein/packing) is 14.61 mg·g^-1. After storage for 7 and 30 d, the microorganisms fixed on the packing material could still remove more than 96% of butyl acetate. The BTF using SC as packings reach stable performance within a short time (8 d) and the removal efficiency is maintained at 94% unless there nutrition is supplied or the pH is adjusted. The BTF with polyurethane as packing material need a longer time to start up and the removal efficiency decreases to 80% under the same operating conditions. High-throughput sequencing analysis shows that the fixed degrading stains are dominant during the whole operation and the microbial structure is more stable, which could sustain the stable removal of butyl acetate in BTF using SC.

[Effects of four different nasal packing materials after endoscopic sinus surgery]

Objective:To investigate effects of four different types of nasal packs after endoscopic sinus surgery. Method:Sixty patients with chronic rhinosinusitis who underwent endoscopic sinus surgery were evaluated preoperatively using visual analog symptom scale, Lund-Kennedy endoscopy scoring scale, and Lund Mackay CT scoring scale.All patients received nasal packing after operative, and divided into four groups based on the nasal packs used: nasopore group (16 cases), merocel group (16 cases), vaseline gauze group(16 cases) and merocel with vaseline gauze group(12 cases). All packs were removed 48 to 72 hour after the surgery. Clinical effects of four nasal packs were evaluated based on following indexes: pain after twelve hours of nasal packing, bleeding during nasal packing, pain and bleeding during packing removal, difficulty of packing removal. Result:The lowest degree of forementioned five different indexes was found in Nasopore group, and was significantly different with other three groups(P <0.05), merocel produced the highest bleeding during nasal packing,which had significant difference with other three groups(P <0.05), vaseline gauze produced the highest pain during nasal packing and packing removal, which had significant difference with other three groups(P <0.05), merocel combined vaseline gauze had no significant difference with merocel on the pain during nasal packing and packing removal(P >0.05), and it had no significant difference with vaseline gauze on bleeding during nasal packing, bleeding upon packing removal and degree of difficulty or ease upon packing removal(P >0.05).Conclusion:As a new type of high expansion absorbable nasal packing products applied after FESS, nasopore has the advantages of good hemostatic effect,higher nasal comfort level,least bleeding upon packing removal and so on. At the same time, the implementation of personalized mixed nasal packing of different materials could make up for the various defects when used alone,gained better clinical effect and worthy of clinical popularization and application.