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Staphylococcus aureus biofilm is a common bio-contaminant source that leads to food cross-contamination and foodborne disease outbreaks. Hence, there is a need for searching novel antibiofilm agents with potential anti-virulence properties to control S. aureus contamination and infections in food systems. In this study, the antibiofilm effects of lactobionic acid (LBA) against S. aureus and its influence on virulence were explored. The minimum inhibition concentration of LBA on S. aureus was 8 mg/mL. Viable count and crystal violet assays revealed that LBA inhibited and inactivated S. aureus biofilms. Microscopic observations further confirmed the antibiofilm activity of LBA on S. aureus that disrupted the biofilm architecture and inactivated the viable cells in biofilms. Moreover, LBA decreased the release of extracellular DNA (eDNA) and extracellular polysaccharide (EPS) in S. aureus biofilms. LBA suppressed biofilm formation by intervening metabolic activity and reduced virulence secretion by repressing the hemolytic activity of S. aureus. Furthermore, LBA altered the expressions of biofilm- and virulence-related genes in S. aureus, further confirming that LBA suppressed biofilm formation and reduced the virulence secretion of S. aureus. The results suggest that LBA might be useful in preventing and controlling biofilm formation and the virulence of S. aureus to ensure food safety. [ABSTRACT FROM AUTHOR]

Food heating process causes increased protein glycation and the formation of advanced glycation endproducts (AGEs) which related with diabetes and ageing. Aloe vera ( A. vera) extract is a potent antioxidant with established effects attributed largely to a key ingredient anthraquinone. This study investigated the inhibitory ability of the three anthraquinones from A. vera on the formation of AGEs in a heated model system at 70°C. Anthraquinones, including aloe-emodin (AED), emodin (ED), and chrysophanol (CSN), were extracted from A. vera and analyzed by ultra-high performance liquid chromatography-tandem mass spectrometry. Under optimal extraction conditions, the extraction yield of the anthraquinones was 4.377 mg/g. Anthraquinones showed good inhibition toward the formation of glycation products; the inhibition rates of AED, ED, and CSN on crosslinked AGEs were 46.48%, 66.38%, and 57.32% at 10 μM concentrations. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis images also proved that the anthraquinones could significantly inhibit crosslinked AGE formation in a time-dependent manner. ED showed higher inhibitory ability than AED and CSN on the formation of Nɛ-(carboxymethyl)lysine and crosslinked AGEs. The results indicate that the antiglycation properties of these anthraquinones are likely related to the phenolic hydroxyl groups in their structures, but this ability is not related to their antioxidant activity, which probably depends on the whole structure of the quinone. Generally, the anthraquinones in A. vera, especially ED, can effectively inhibit AGE formation and reduce protein crosslinking during food processing, even at low concentration. Practical applications The inhibitory effects of three anthraquinones extracted from Aloe vera on the formation of AGEs were investigated in a heated model system. The results indicate Aloe can be used as an effective inhibitor of glycation products in food processing, moreover, this research can be useful for finding suitable nature inhibitors of AGEs for food processing. [ABSTRACT FROM AUTHOR]

Advanced glycation end products (AGEs) are common by-products of food preparation and are associated with an increased risk of diabetes and uremia. The objective of this investigation is to determine the level of crosslinked AGEs (AGE-fl) and Nε-(carboxymethyl)lysine (CML) in 24 kinds of foods consumed in China. AGE-fl and CML contents were compared, and the effects of culinary treatments and food composition on their abundance were investigated. The results showed that the composition of the foods strongly influences the CML and AGE concentrations ( P < 0.05), but no obvious correlation was found between the contents of AGE-fl and CML. Along with dehydration, compared with main reactions caused by heating, oxidation effectively contributes to CML production, and the correlation coefficient between the peroxide value (POV) and the CML content is 0.86. These data can be used for improving the culinary treatment methods of foods common in the Chinese cuisine. Practical Applications The amount of crosslinked AGEs in 24 kinds of Chinese foods and effects of culinary treatment methods and material composition were investigated. These data can be used for improving the culinary treatment methods of foods common in Chinese cuisine and other cuisines. [ABSTRACT FROM AUTHOR]