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BACKGROUND The application of Pickering emulsions stabilized by food‐derived particles is of great interest, studies have focused on development of natural functional emulsifiers from agricultural byproducts. Dietary fiber (DF) has been recognizing for its excellent physiological functions. Moreover, physicochemical properties of pomelo peel DF (PDF) make it a potential emulsifier. However, pristine PDF is not suitable as emulsifier due to its compact physical structure and high hydrophobicity, which seriously limits its utilization. The objective of the study was to investigate the effects of cellulase on physicochemical properties of PDF and to illustrate the feasibility of cellulase modified PDF (MPDF) as natural functional emulsifier. RESULTS: Cellulase modification significantly improved (P < 0.05) specific surface area, water‐holding capacity/oil‐holding capacity, viscoelasticity, hydrophobicity, and pore structure while decreased crystallinity index and particle size of PDF. Emulsion could remain stable over 30 days as MPDF concentrations up to 1 wt% and oil/water ratio 3:7. The appearance stability of emulsions was not influenced by temperature (4–60 °C), pH (3.0–12.0), and ion concentration (0–200 mmol L−1) which was similar to Pickering emulsions. The mechanism of MPDF as an emulsifier was mainly attributed to the combination of Pickering effect and the three‐dimensional network. In addition, MPDF showed higher antioxidant capacity in emulsions than other classical emulsifiers. CONCLUSION: The results illustrated that MPDF has a favorable feasibility for preparation of stable Pickering‐type emulsions, which will be a practical support for application of PDF as a natural functional emulsifier and will be helpful to realize the resource utilization of DF in pomelo industries. © 2022 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Tannase is an enzyme produced by microbial fermentation and is widely used in the food industry; however, the molecular mechanism of tannase production by Aspergillus has not yet been studied. This study was conducted to reveal the differences in Aspergillus carbonarius tannase enzymatic characterization, secondary structures and molecular mechanisms after treatment of the strain with atmospheric and room temperature plasma (ARTP). RESULTS: The results showed that the specific activity of tannase was improved by ARTP treatment, and it showed higher thermostability and tolerance to metal ions and additives. The enzymatic characterization and molecular docking results indicated that tannase had a higher affinity and catalytic rate with tannic acid as a substrate after ARTP treatment. In addition, the docking results indicated that Aspergillus tannases may catalyze tannic acid by forming two hydrogen‐bonding networks with neighboring residues. RNA‐seq analysis indicated that changes in steroid biosynthesis, glutathione metabolism, glycerolipid metabolism, oxidative phosphorylation pathway and mitogen‐activated protein kinase signaling pathways might be crucial reasons for the high production of tannase. CONCLUSION: ARTP enhanced the yield and properties of A. carbonarius tannase by changing the enzyme structure and cell metabolism. This study provides a theoretical basis for elucidating the molecular mechanism underlying high production of Aspergillus tannases. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]