Optimization of the Preparation Process of Oyster Peptide by Enzymatic Hydrolysis and Its Effects on Testosterone Secretion and Oxidative Stress in Mouse Testicular Interstitial Cells

In order to explore the research and development of oyster in the field of medicine and food homology, response surface methodology was used to optimize the preparation process of oyster protease-depeptidase, and its effects on testosterone secretion and oxidative stress in mouse leydig cells were studied. Based on the investigation of hydrolysis degree as the evaluation index, a biomimetic enzymatic hydrolysis method was employed to optimize the preparation process of oyster protein enzymolysis peptides using response surface analysis, building upon the foundation of single-factor experiments. Simultaneously, a hydrogen peroxide (H2O2)-induced oxidative damage model was established using mouse testicular interstitial cells (TM3), and the effects of oyster protein enzymolysis peptides on testosterone (T) secretion and oxidative stress were investigated through assessments of cell viability, DAPI staining, testosterone secretion level, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) content in TM3 cells. The results showed that the optimal enzymatic hydrolysis conditions for oyster protein enzymolysis peptides were as follows: Substrate-to-solvent ratio of 1:10 g/mL, gastric protease concentration of 1.1%, hydrolysis time of 1.0 h, pancreatic protease concentration of 2.1%, and hydrolysis time of 3.1 h. Under these conditions, the degree of hydrolysis was determined to be 39.43%±0.42%. Oyster protein enzymolysis peptides exhibited varying degrees of proliferative activity on H2O2-induced TM3 cells, significantly (P<0.05) increasing testosterone secretion, SOD enzyme activity, and reducing MDA levels in TM3 cells. The most pronounced effects were observed at a concentration of 200 μg/mL of oyster protein enzymolysis peptides. In conclusion, the optimization of enzymatic hydrolysis process using response surface methodology proved to be effective and feasible. Oyster protein enzymolysis peptides was found to extremely significant promote TM3 cell proliferation, increase testosterone secretion, enhance SOD enzyme activity, and reduce MDA levels (P<0.01)

An empirical study on the response of university students to viewing autumn secondary forest phytocommunities landscape via virtual reality in Northeast China

Secondary forests play a critical role in the natural environment and have the potential to provide significant benefits for human physical and mental well-being. The secondary forests in the Sanhu National Nature Reserve, located in Northeast China, have extremely high ecological value. In this study, we selected seven types of secondary forest phytocommunities in this region, measured ecological indicators at various sites, and captured panoramic photos on-site. Virtual reality (VR) technology was used to present and record participants' electroencephalogram (EEG) data for studying neural activity. Statistical analyses were conducted using SPSS 26.0 to evaluate the data obtained from the study. The results showed that participants preferred landscapes predominantly consisting of mixed forests of Pinus koraiensis mixed broad-leaved forest (FP1.α and FP2.α: p = 0.001), featuring colorful and verdant scenery. Experiencing these seven types of secondary forest landscapes through virtual reality improved participants' mood and had a positive impact on them. Within a certain range (300–400 m, 0-30°), participants favored landscapes with higher elevations (FP1.β: p = 0.008, FP2.β: p = 0.001, F3.β: p = 0.006) and gentler slopes (F3.θ: p = 0.002, F4.θ: p = 0.031, F8.θ: p = 0.005). Additionally, participants showed a preference for secondary forest landscapes with a moderate canopy density ranging from 0.7 to 0.8 (FP1.θ: p = 0.015, FP2.θ: p = 0.014). The study also found that participants preferred landscapes with a greater abundance of trees and shrubs, as well as taller and narrower trees. Moreover, our study revealed that males favored autumn forest landscapes more than females, with graduate students showing a stronger preference compared to undergraduates. Urban residents also displayed a stronger preference for these landscapes over rural residents, and individuals from the Southern region expressed a higher inclination than their Northern counterparts (T3.δ: p = 0.002, p = 0.001 for others). These findings can provide reference for the design and plant arrangement of urban forest landscapes