Preparation of an LZ-OEO Compound Antibacterial Gel and the Effect of Microwave Treatment on Its Structure and Stability.

Composite gels prepared with ovalbumin (OVA) as basic materials have been gradually utilized in food and biological fields. However, the structure and function of gels made from natural materials are not perfect, especially the hardness, viscoelasticity and water-holding capacity of gels, which are easily affected by various factors (pH, NaCl, etc.). In order to improve the antibacterial effect and safety of gels, and on the basis of exploring the bacteriostatic formula of lysozyme-oregano essential oil (LZ-OEO), the influence of microwave treatment on the stability of the composite bacteriostatic material gel was emphatically investigated and discussed so as to develop a new bacteriostatic gel material. The results revealed that the LZ-OEO antibacterial gel prepared by adding 20% OEO, with a ratio of 3:2 between OVA and LZ, was more stable after microwave treatment, and the synergistic antibacterial effect was significantly improved. That is, the OVA and LZ-OEO composite gel processed using a 350 W microwave treatment for 1 min had the highest hardness, the water-holding capacity reached 78.05% and a dense and ordered network structure was formed. In addition, the compound gel displayed excellent antibacterial effects against Staphylococcus aureus and Escherichia coli. The experimental findings in this study effectively expands the application scope of lysozyme antibacterial materials and provides a more favorable technical foundation for future development and utilization.

Multi-Omics Analysis of the Effects of Egg Ovotransferrin on the Gut Environment in Mice: Mucosal Gene Expression, Microbiota Composition, and Intestinal Structural Homeostasis.

SCOPE: Egg ovotransferrin (OVT) is considered a functional food ingredient for its various bioactivities. The objective of this work is to explore the potential biological activity of OVT on the gut health. METHODS AND RESULTS: Both young (3 week old) and adult (8 week old) mouse models are utilized in this research. Each group receives a standard diet containing either OVT (experimental group) or distilled water (control group) for a 14 day period. Transcriptome and 16S rDNA sequencing analyses are applied to characterize the gene expression in colonic epithelial cells and gut microbiota composition. In the young groups, OVT suppresses the genes correlated with lipid metabolism and signal transduction. The regulated genes in the adult groups encompass various biological processes, including lipid metabolism, signal transduction, endocrine system, and others. OVT increases the proportion of some beneficial bacteria significantly, especially Akkermansia, and inhibits some harmful bacteria. Furthermore, OVT affects mucosal morphology positively via increasing the crypt depth. OVT also increases the expression of tight junction protein occludin by 3.0- and 5.2-folds in young and adult groups, respectively. CONCLUSION: OVT exhibits some beneficial effects on the gut environment. These positive findings provide new insight into the understanding of OVT as an excellent functional ingredient.

Application of high EPA-producing Mortierella alpina in laying hen feed for egg DHA accumulation.

Polyunsaturated fatty acids (PUFAs), especially eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6), are beneficial for human health. In this study, we selected a high EPA content (30% in total fatty acids) strain of Mortierella alpina CCFM 698 that overexpressed an ω-3 fatty acid desaturase from Phytophthora parasitica, and investigated the cell growth and lipid accumulation of this strain in a 65 L airlift fermenter with glucose batch feeding. The maximum cell dry weight was 28.7 g L-1 and the highest total fatty acid content was 33.0% (w/w) in cell dry weight. The highest EPA yield was 1.8 g L-1. Both low and high dose supplementation of this strain into the feed of laying hens increased DHA accumulation in the yolk. The highest DHA content of 7.61 mg g-1 yolk was achieved in Fengda-1 laying hens with 4% supplementation and the DHA production per egg was 118.46 mg. However, Hy-Line Brown laying hens displayed a higher DHA production per egg and the value was 131.50, 131.72, 131.95 mg with 1.5%, 2%, 4% supplementation, respectively. The lowest ratio of ω-6/ω-3 PUFAs (3.53) was obtained in Hy-Line Brown laying hens with 4% supplementation. These results suggest that M. alpina CCFM 698 can be used as an alternative source of ω-3 PUFAs in feed to produce nutritious eggs with high DHA content.