Angiotensin-converting enzyme inhibitory peptide IVGFPAYGH protects against liver injury in mice fed a high­sodium diet by inhibiting the RAS and remodeling gut microbial communities.

Consuming a high­sodium diet carries serious health risks and significantly influences the activation state of the renin-angiotensin system (RAS). This study evaluates the protective effect of angiotensin-converting enzyme (ACE) inhibitory peptide IVGFPAYGH on a high­sodium diet-induced liver injury. IVGFPAYGH supplementation increased the activities of liver antioxidase and decreased the levels of liver inflammatory factor in mice fed a high­sodium diet (8 % NaCl). IVGFPAYGH supplementation also reduced liver fatty acid synthesis and promoted fatty acid oxidation, increased the expression of low-density lipoprotein receptor, and improved liver dyslipidemia. Furthermore, IVGFPAYGH supplementation inhibited the activation of the liver RAS via inhibiting ACE activity and reducing angiotensin II levels in mice fed a high­sodium diet. Moreover, IVGFPAYGH supplementation could alter the gut microbiota composition toward a normal gut microbiota composition and increase the abundance of the Lactobacillus genus. IVGFPAYGH supplementation also increased the expression levels of small intestinal tight junction protein and cecum short-chain fatty acids. Thus, IVGFPAYGH supplementation may maintain intestinal homeostasis and improve high­sodium diet-induced liver injury by altering the gut microbiota composition and inhibiting the RAS. IVGFPAYGH is a promising functional ingredient for protecting liver damage caused by a high­sodium diet.

Significant inhibition of garlic essential oilon benzo[a]pyrene formation in charcoal-grilled pork sausagesrelates to sulfide compounds.

To addgarlic more conveniently, the substitute-garlic essential oil(GEO)is wildly applied in meat product for flavor improvement. However, the effects of GEOon chemical hazard formation, such as benzo[a]pyrene (BaP), in meat processing have not been studied. This study focused on the inhibitory effect of garlic (0.05-0.15%, w/w), GEO (0.002-0.006%, w/w) and the active sulfide compounds (0.006%, w/w) on the formation of BaP in charcoal-grilled pork sausages. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity of the garlic, GEO and sulfide compounds was also determined. The results showed that the garlic was efficient in the decrease of DPPH free radicals (14.91-23.39%) and BaP content (37.2-62.3%). GEO was also efficient in scavenging DPPH free radicals (14.17-26.20%) and reducing BaP formation (29.1-57.1%). Gas chromatography-mass spectrometer (GC-MS) analysis identified a total of 41 compounds, of which six major sulfide compounds (allyl methyl sulfide, diallyl sulfide, allyl methyl disulfide, diallyl disulfide, allyl methyl trisulfide and diallyl trisulfide) were screened to assess their inhibition of BaP generation. The BaP inhibition of these sulfide compounds were dependent on the number of sulfur (-S-) and thioallyl group (-S-CH2-CH═CH2); and allyl methyl trisulfide (AMTS) showed the highest BaP inhibition (63.3%). A significant correlation was found between their BaP inhibition and DPPH scavenging activity (Spearman correlation = 0.91, P < 0.001), which indicates that the mechanism of sulfides influencing BaP formation in grilling sausage is related to free radical reaction. Our research gives an insight into the theoretical basis about application of GEO to inhibit BaP during food processing and supports use of GEO as a natural additive in meat products.