In wound care management, the prevention of wound infection and the retention of an appropriate level of moisture are two major challenges. Therefore, designing an excellent antibacterial hydrogel with a suitable water-adsorbing capacity is very important to improve the development of wound dressings. In this paper, a novel silver nanoparticles/poly (gamma-glutamic acid) (γ-PGA) composite dressing was prepared for biomedical applications. The promoted wound-healing ability of the hydrogels were systematically evaluated with the aim of attaining a novel and effective wound dressing. A diffusion study showed that hydrogels can continuously release antibacterial factors (Ag). Hydrogels contain a high percentage of water, providing an ideal moist environment for tissue regeneration, while also preventing contraction of the wound. Moreover, an in vivo, wound-healing model evaluation of artificial wounds in mice indicated that silver/γ-PGA hydrogels could significantly promote wound healing. Histological examination revealed that hydrogels can successfully help to reconstruct intact epidermis and collagen deposition during 14 days of impaired wound healing. Overall, this research could shed new light on the design of antibacterial silver/γ-PGA hydrogels with potential applications in wound dressing.

In this paper, poly γ-glutamic acid/ε-polylysine (γ-PGA/ε-PL) hydrogels were successful prepared. The γ-PGA/ε-PL hydrogels could be used to remove Na⁺, Ca²⁺, and Cr³⁺ from aqueous solution and were characterized by scanning electron microscopy. The performance of hydrogels were estimated under different ionic concentration, temperature, and pH. The results showed that the ionic concentration and the pH significantly influenced the swelling capacity of γ-PGA/ε-PL hydrogels. The swelling capacities of γ-PGA/ε-PL hydrogels were decreased with the increase of the ionic concentration. However, the swelling capacity of the γ-PGA/ε-PL hydrogel was increased with the increase of the pH. The swelling kinetics indicated that γ-PGA/ε-PL hydrogels presented a more limited swelling degree in metal ion solutions with higher ionic valence numbers than in ion solutions with lower ionic valence numbers. However, the swelling kinetics of γ-PGA/ε-PL hydrogels showed that they proposed a satisfactory description in NaCl and CaCl₂ solutions. The adsorption process was fitted with a pseudo-second-order rate equation model. Moreover, the desorption kinetics of γ-PGA/ε-PL hydrogels showed that they could release most of the adsorption ions. Considering the biocompatibility, biodegradability, and ionic-sensitive properties, we propose that these γ-PGA/ε-PL hydrogels have high potential to be used in environmental protection, medical treatment, and other related fields.

Extracellular enzymes play an important role in the growth and development of edible fungi. Extracellular enzyme activities have also become an important object of measurement. In this study, Agaricus brunnescens Peck, Coprinus comatus, and Pleurotus ostreatus were compared in terms of their enzyme production in liquid-and solid-state fermentation. Differences in the ability of various types of edible fungi to utilize biomass raw materials were analyzed by monitoring the fiber degradation rate during crop straw degradation, and changes in their cellulolytic enzyme systems during growth and metabolism were discussed. This study provided insights into the changes in the lignocellulose degradation ability of edible fungi during their growth and facilitated the discovery of new approaches to accelerate their growth in culture.

To evaluate pharmacological activities of a novel fungus Hygrophoropsis sp., the influence of aeration rate on the production of mycelial biomass, exopolysaccharides (EPS), and intrapolysaccharides (IPS) in the fungus Hygrophoropsis sp. was investigated. And the water extracts of cultured Hygrophoropsis sp. mycelia and the fermentation broth were analyzed for their antioxidation activity by using four different assay methods such as hydroxyl radical scavenging, superoxide radical scavenging, hydrogen peroxide scavenging, and reducing power. The Hygrophoropsis sp. was cultivated under various aeration rates in a 7l bioreactor. The highest mycelial biomass (3.98mg/mL) and IPS production (19.63mg/g) were obtained at aeration rate 4.5 v.v.m. The results showed that Hygrophoropsis sp., in general, possesses a strong antioxidation activity in all assays tested. The deproteinized extracts had stronger antioxidation activity as compared to the un-deproteinized extracts by using superoxide radical scavenging, hydrogen peroxide scavenging, and reducing power. Besides, the un-deproteinized extracts had stronger antioxidation activity as compared to the deproteinized extracts by using hydroxyl radical scavenging. Thus, the polysaccharide extractions from the Hygrophoropsis sp. studied have antioxidant activities in vitro, which may be a good source of natural antioxidants or further investigation as potential natural antioxidants.