Xiufang Dong

Bio: Xiufang Dong is an academic researcher from Qingdao University of Science and Technology. The author has contributed to research in topics: Apostichopus japonicus & Protein oxidation. The author has an hindex of 1, co-authored 5 publications receiving 4 citations. Previous affiliations of Xiufang Dong include Dalian Polytechnic University.

Orally Administered DHA Enriched Phospholipids and DHA Enriched Triglyceride Relief Oxidative Stress, Improve Intestinal Barrier, Modulate Inflammatory Cytokine and Gut Microbiota, and Meliorate Inflammatory Responses in the Brain in DSS-Induced Colitis in Mice.

Abstract: Scope Studies based on DHA/EPA supplementation in animal models of inflammatory bowel disease (IBD) revealed controversial results. We speculated different forms of DHA may explain the controversial results. Therefore, we compared the effects of DHA enriched phospholipids (DHA-PL) and DHA enriched triglyceride (DHA-TG) on IBD. Method and results Male C57BL6/J mice were given DHA-PL and DHA-TG for 14 consecutive days, and received ad libitum a 3.0% dextran sodium sulfate solution on the 8th day to establish IBD model. The results showed that both DHA-PL and DHA-TG could reverse the colitis pathological process by decreasing the disease activity indexes (DAI), raising the colon length, suppressing the intestinal permeability, suppressing the oxidative stress, down-regulating pro-inflammatory factors, up-regulating anti-inflammatory factor in colon tissues. DHA-PL and DHA-TG also regulated the composition of gut microbiota via decreasing of the abundance Bacteroidetes and Firmicutes, and DHA-TG increased the abundance of Odoribacter. Importantly, DHA-PL and DHA-TG obviously attenuated the activation of microglia. Conclusions DHA-PL showed outstanding advantages in regulating oxidative stress, inflammatory responses and intestinal barrier permeability. The current research indicated that the existence of DHA affected the improvement, DHA in phospholipid form could be a more effective choice for nutritional intervention to prevent and treat colitis. This article is protected by copyright. All rights reserved.

Effects of oxidation on the structure of collagen fibers of sea cucumber (Apostichopus japonicus) body wall during thermal processing

Abstract: Thermal treatment during sea cucumber processing might affect the texture of the final product. In the present study, collagen fibers (CFs) extracted from the body wall of sea cucumber Apostichopus japonicus were used to investigate the effects of heating and oxidative conditions on CFs structure. Hydroxyl radicals (•OH) were generated in CFs treated at 37 °C and the intensity of the signal was comparable to samples under oxidative conditions at 4 °C. Release of protein and glycosaminoglycan was observed in CFs heat-treated at 37 °C or under oxidative conditions at 4 °C, leading to the conversion of α-helixes into β-sheets, red shift of amide band I, decrease in thermostability, and scattered arrangement of collagen fibrils. The degree of damage in CFs structure is different among groups. In particular, in thermally- and oxidative treated group, macromolecular fragments remarkably degraded over time, 10 kDa proteins were abundantly released, amide bands A and III showed redshift, and maximum denaturation temperature and decomposition temperature were the lowest compared to other groups. The findings discussed herein reveal the structural changes induced by thermal treatment in sea cucumber CFs and provide an explanation of the mechanism from the view of protein oxidation.

Protein oxidation results in textural changes in sea cucumber (Apostichopus japonicus) during tenderization

Abstract: Low-temperature tenderization is an important aspect in the processing of sea cucumber. Oxidative reactions induce protein aggregation or degradation during thermal treatment. However, whether protein oxidation occurs in sea cucumber during tenderization is unclear. Moreover, the effects of heat treatment on the protein structure in sea cucumber have not been well explored. In this study, Apostichopus japonicus body wall (AJBW) were tenderized at 37 °C and changes in the protein microstructure of AJBW and the relative indicators of oxidative reactions, including carbonyl, sulfhydryl, and amino constituents, were investigated. The findings indicated that the collagen fibers were depolymerized and the maximum denaturation temperature of collagen was significantly reduced after tenderization, suggesting that this process induced structural changes in collagen fibers. Furthermore, amino acid side-chain modifications and the formation of an unstable secondary and tertiary conformation indicated oxidation of the water-soluble proteins. The findings revealed that tenderization of AJBW caused the destruction of the collagen fiber structure and resulted in protein oxidation and degradation. Therefore, our study lays the foundation for subsequent research for determining the mechanism of tenderization.

Virgibacillus sp. SK37 and Staphylococcus nepalensis JS11 as potential starters to improve taste of shrimp paste

Abstract: The objective of this study was to investigate the effects of halophilic bacteria, including Virgibacillus sp. ZV10-1, Virgibacillus sp. SK37, and Staphylococcus nepalensis JS11 as starters on physicochemical, sensory, and taste properties of rapidly-fermented shrimp paste. Halophilic bacteria reduced moisture and total volatile basic nitrogen content and increased the pH and amino acid nitrogen content of shrimp pastes. Higher levels of total organic acids (484.47 ± 10.40 mg/100 g) were detected in sample inoculated with S. nepalensis JS11. Assessment of sensory parameters indicated that the three-bacteria compound inoculation group improved taste of shrimp paste effectively and contained the highest level of free amino acids (8930.25 ± 3.51 mg/100 g) and equivalent umami concentration (EUC) (960.32 g MSG/100 g). Furthermore, partial least squares regression analysis demonstrated that rapidly-fermented shrimp pastes were associated with sweetness, umami, color, texture, and overall liking attributes, which were related to the presence of tartaric acid, malic acid, GMP, Glu, Asp, Arg and Thr. Thus, this study highlights the potential of Virgibacillus sp. SK37 and S. nepalensis JS11 for the production of rapidly-fermented shrimp paste with improved taste profiles.

Characterization of aroma profiles and aroma-active compounds in high-salt and low-salt shrimp paste by molecular sensory science

Abstract: Flavor characteristics of raw shrimp, high-salt and low-salt shrimp paste were evaluated and compared by sensory analysis, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). In addition, aroma profiles and aroma-active compounds in these three samples were analyzed by solvent-assisted flavor evaporation-gas chromatography-olfactometry-mass spectrometry (SAFE-GC-O-MS). Results of sensory evaluation revealed that these three samples showed significant differences in sensitivity to the W2W, W2S, W1S and W1W sensors of the electronic nose (p < 0.05), which represent organic sulfides, alkane aromatic compounds, short chain alkanes, and sulfides, respectively. Assessment of sensory parameters indicated tha high-salt shrimp paste had a strong roasted and meaty aroma, while low-salt shrimp paste showed an umami aroma more similar to raw shrimp. A total of 118 volatile compounds were identified using the three afore-mentioned gas chromatography methods. Among them, 37 aroma-active compounds were detected by GC-O. High-salt shrimp was shown to contain more acids, aldehydes and heterocyclic compounds, which resembled cheese, roasted and meaty aromas. In contrast, low-salt shrimp paste contained more esters, which was similar to the umami aroma profile of raw shrimp. Interestingly, pyrazines were only produced in fermented shrimp paste samples, suggesting that they were produced during the fermentation process and they may contribute unique roasted and meaty aromas, which were important for the overall aroma characteristics of shrimp paste.

Characterization of aroma profiles and aroma-active compounds in high-salt and low-salt shrimp paste by molecular sensory science

Abstract: Flavor characteristics of raw shrimp, high-salt and low-salt shrimp paste were evaluated and compared by sensory analysis, headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). In addition, aroma profiles and aroma-active compounds in these three samples were analyzed by solvent-assisted flavor evaporation-gas chromatography-olfactometry-mass spectrometry (SAFE-GC-O-MS). Results of sensory evaluation revealed that these three samples showed significant differences in sensitivity to the W2W, W2S, W1S and W1W sensors of the electronic nose (p