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[Objective] This study aimed to improve the processing characteristics of collagen. [Methods] Using pig skin collagen and enzymatic hydrolysis pig skin collagen (H-PC) as a control, the antioxidant, emulsification, and other functional properties of the complex after enzymatic hydrolysis and glycosylation (HG-PC) were analyzed. The structure of HG-PC was studied by UV-VIS spectrum, fluorescence spectrum, and Fourier infrared spectrum. [Results] The results showed that compared with PC and H-PC, the DPPH free radical scavenging rate, water retention, emulsification, emulsification stability, foaming stability, and foaming stability of HG-PC were significantly increased (P＜0.05). While the oil retention, surface hydrophobicity, and turbidity of HG-PC were significantly decreased (P＜0.05). The UV absorption intensity of HG-PC was increased, and the fluorescence intensity was decreased, the protein secondary structure of which was destroyed. [Conclusion] The synergistic modification of enzymatic hydrolysis and glycosylation can significantly change the properties of PC, and the synergistic modification effect is better than single modification.

In order to explore the effects of spray freeze drying (SFD) on the structure and functional properties of ovalbumin (OVA) and ovomucin (OVM), the spray drying (SD) and vacuum freeze drying (FD)were used as the control. The structure was analyzed by low field nuclear magnetic resonance, Fourier transform infrared spectroscopy, fluorescence spectroscopy, differential scanning calorimetry and scanning electron microscope. The results show that the free water of spray freeze-dried samples is decreased, and the binding water increases and water retention increases. SFD interacting proteins α-helix and β-folding structure is large and the degree of protein aggregation is small. The fluorescence peak intensity at wavelength 340 nm is SFD>FD>SD. The denaturation temperature of SFD interacting proteins is 51.37 °C, which is lower than that of SD, and close to FD protein. SFD interacting proteins have a spherical structure and internal space is network structure. The emulsifying property, solubility, foaming ability and foam stability of the SFD interacting proteins are close to those of FD Protein, and are significantly better than those of spray dried samples (P<0.05). The apparent viscosity of the SD protein is larger than that of the SFD protein. The storage modulus is higher than the loss modulus. SFD is suitable for processing because of the high cost of FD. [ABSTRACT FROM AUTHOR]

Objective: To analyze the differences and similarities of pre-treatment and post-treatment lung microbiome of acute respiratory distress syndrome (ARDS) and find out the change rules of the lung microbiome in the progression of ARDS according to different prognosis., Methods: A retrospective study was conducted. Patients with ARDS caused by severe pneumonia admitted to intensive care unit (ICU) of Jiangmen Central Hospital from February 2019 to January 2020 were enrolled as the study subjects. The patients were divided into pre-treatment (ARDS-preT) group (24 cases), post-treatment survival (ARDS-poT-Survival) group (17 cases), and post-treatment death (ARDS-poT-Dead) group (7 cases). ICU patients with mild pulmonary infection and non-ARDS admitted to ICU during the same period were enrolled as control group (25 cases). The similarities and differences of lung microbiome in four groups were analyzed and compared, and the possible pathogenic bacteria (potential risk factors for death) and probiotics (potential survival and protective factors) related to death caused by ARDS were screened., Results: In terms of pathogenic microorganisms, the positive rates of Escherichia coli and Candida albicans in the ARDS-poT-Dead group were significantly higher than those in the ARDS-poT-Survival group [57.1% (4/7) vs. 5.9% (1/17) and 57.1% (4/7) vs. 0% (0/7), both P < 0.05]. In the screening of background bacteria, the decrease of bacteria in the ARDS-preT group compared with the ARDS-poT-Survival group, the ARDS-poT-Dead group compared with the ARDS-poT-Survival group, the ARDS-poT-Dead group compared with the control group, the reduced bacteria might be pulmonary probiotics (potential protective factor for ARDS). The screening result was Hydrobacter [ARDS-preT group vs. ARDS-poT-Survival group: 62.5% (15/24) vs. 94.1% (16/17); ARDS-poT-Dead group vs. ARDS-poT-Survival group: 14.3% (1/7) vs. 94.1% (16/17); ARDS-poT-Dead vs. control: 14.3% (1/7) vs. 96.0% (24/25), all P < 0.05]. In the screening of background bacteria, the increase of bacteria in the ARDS-poT-Dead group compared with the ARDS-preT group, the ARDS-poT-Dead group compared with the ARDS-poT-Survival group, the ARDS-poT-Dead group compared with the control group, and the increased bacteria might be potential pulmonary pathogen (potential risk factor for death of ARDS), which belonged to Enterobacteria: Edwardsiella, Enterobacteriaceae, Escherichia, Klebsiella, Kluyvera, Lelliottia, Pantoea, Raoultella., Conclusions: The results revealed the increase of Escherichia coli or Candida albicans in pulmonary pathogenic microorganisms, or the increase of Enterobacteria in background bacteria may be the risk factors for the death of ARDS. Additionally, background bacteria Hydrobacter probably is a protective factor for the survival of ARDS. Whether it can be used as a novel treatment for ARDS is worth further investigation.