Rosemary Extracts Improved the Antioxidant Status of Low-Fat Yoghurt Sauces Enriched with Inulin

Rosemary leaf powder improves egg quality, antioxidant status, gut barrier function, and cecal microbiota and metabolites of late-phase laying hens

This study sought to determine the effects of rosemary leaf powder (RP) on laying performance, egg quality, serum indices, gut barrier function, and cecal microbiota and metabolites of late-phase laying hens. A total of 84 "Jing Tint 6" laying hens at 65-week old were randomly divided into 2 groups and fed either a basal diet (CON) or a basal diet supplemented with 0.3% RP. Our study revealed that RP improved the Haugh unit and decreased yolk n-6/n-3 polyunsaturated fatty acid (PUFA) ratio of laying hens, increased serum superoxide dismutase (SOD), jejunal activities of SOD and catalase (CAT), and jejunal zonula occludens-1 (ZO-1) expression, as well as decreased serum tumor necrosis factor-α (TNF-α) level and jejunal TNF-α mRNA expression. Rosemary leaf powder markedly enhanced (P < 0.05) cecal abundances of Rikenellaceae, Rikenellaceae_RC9_gut_group, and Turicibacter, tended to promote (P = 0.076) butyrate concentration, and reduced (P < 0.05) cecal abundances of Erysipelatoclostridiaceae, Sutterellaceae, Fusobacteriaceae, Campylobacteraceae, Sutterella, Campylobacter, and Fusobacterium, which were closely linked with Haugh unit, yolk n-6/n-3 PUFA ratio, serum SOD and TNF-α. In addition, RP altered the metabolic functions of cecal microbiota and enhanced the abundances of butyrate-synthesizing enzymes, including lysine 2,3-aminomutase, β-lysine 5,6-aminomutase, and 3-oxoacid CoA-transferase. Together, 0.3% RP has the potential to enhance egg quality by partially modulating serum antioxidant status, jejunal barrier function, and cecal microbiota structure and metabolites, indicating that RP could be considered a promising feed additive to promote the production performance of late-phase laying hens.

Rosemary extract improves egg quality by altering gut barrier function, intestinal microbiota and oviductal gene expressions in late-phase laying hens

BACKGROUND

Rosemary extract (RE) has been reported to exert antioxidant property. However, the application of RE in late-phase laying hens on egg quality, intestinal barrier and microbiota, and oviductal function has not been systematically studied. This study was investigated to detect the potential effects of RE on performance, egg quality, serum parameters, intestinal heath, cecal microbiota and metabolism, and oviductal gene expressions in late-phase laying hens. A total of 210 65-week-old "Jing Tint 6" laying hens were randomly allocated into five treatments with six replicates and seven birds per replicate and fed basal diet (CON) or basal diet supplemented with chlortetracycline at 50 mg/kg (CTC) or RE at 50 mg/kg (RE50), 100 mg/kg (RE100), and 200 mg/kg (RE200).

RESULTS

Our results showed that RE200 improved (P < 0.05) Haugh unit and n-6/n-3 of egg yolk, serum superoxide dismutase (SOD) compared with CON. No significant differences were observed for Haugh unit and n-6/n-3 of egg yolk among CTC, RE50, RE100 and RE200 groups. Compared with CTC and RE50 groups, RE200 increased serum SOD activity on d 28 and 56. Compared with CON, RE supplementation decreased (P < 0.05) total cholesterol (TC) level. CTC, RE100 and RE200 decreased (P < 0.05) serum interleukin-6 (IL-6) content compared with CON. CTC and RE200 increased jejunal mRNA expression of ZO-1 and Occludin compared with CON. The biomarkers of cecal microbiota and metabolite induced by RE 200, including Firmicutes, Eisenbergiella, Paraprevotella, Papillibacter, and butyrate, were closely associated with Haugh unit, n-6/n-3, SOD, IL-6, and TC. PICRUSt2 analysis indicated that RE altered carbohydrate and amino acid metabolism of cecal microbiota and increased butyrate synthesizing enzymes, including 3-oxoacid CoA-transferase and butyrate-acetoacetate CoA-transferase. Moreover, transcriptomic analysis revealed that RE200 improved gene expressions and functional pathways related to immunity and albumen formation in the oviductal magnum.

CONCLUSIONS

Dietary supplementation with 200 mg/kg RE could increase egg quality of late-phase laying hens via modulating intestinal barrier, cecal microbiota and metabolism, and oviductal function. Overall, RE could be used as a promising feed additive to improve egg quality of laying hens at late stage of production.

Polyphenol Extracts from Sage (Salvia lavandulifolia Vahl) By-Products as Natural Antioxidants for Pasteurised Chilled Yoghurt Sauce

Sage by-product extracts (SE) are a valuable source of phenolic acids and flavonoids for food applications. The objective was to test two SE as antioxidants in pasteurised chilled yoghurt sauces against oxidation. Two SE of different polyphenol total content and profile were selected: SE38 (37.6 mg/g) and SE70 (69.8 mg/g), with salvianic and rosmarinic acid as the main polyphenols, respectively. Four experimental low-fat yoghurt sauces were formulated: untreated; SE70/2 (0.16 g/kg); SE38 (0.3 g/kg); and SE70 (0.3 g/kg). The stability of phenolic acids, microbiological quality (mesophilic bacteria, moulds and yeasts, and L. monocytogenes), and oxidative stability (lipids, colour, and pH) were studied in the sauces after pasteurisation at 70 °C for 30 min (day 0) and stored by refrigeration (day 42). Pasteurisation and further chilling ensured the microbiological quality and inhibition of microbial growth could not be evidenced, although SE70 showed some antimicrobial potential. Both SE showed good properties as antioxidants for yoghurt sauces. This finding was based on two results: (i) their main polyphenols, salvianic and rosmarinic acids, resisted to mild pasteurisation and remained quite stable during shelf life; and (ii) SE improved radical scavenging capacity, delayed primary and secondary lipid oxidation, and increased colour stability, contributing to sauce stabilisation. SE38 had a better antioxidant profile than SE70; therefore, the selection criteria for SE should be based on both quantity and type of polyphenols. Due to their stability and antioxidant properties, sage polyphenols can be used as natural antioxidants for clean-label yoghurt sauces.

The promotion mechanism of prebiotics for probiotics: A review

Prebiotics and probiotics play a positive role in promoting human nutrition and health. Prebiotics are compounds that cannot be digested by the host, but can be used and fermented by probiotics, so as to promote the reproduction and metabolism of intestinal probiotics for the health of body. It has been confirmed that probiotics have clinical or health care functions in preventing or controlling intestinal, respiratory, and urogenital infections, allergic reaction, inflammatory bowel disease, irritable bowel syndrome and other aspects. However, there are few systematic summaries of these types, mechanisms of action and the promotion relationship between prebiotics and probiotic. Therefore, we summarized the various types of prebiotics and probiotics, their individual action mechanisms, and the mechanism of prebiotics promoting probiotics in the intestinal tract. It is hoped this review can provide new ideas for the application of prebiotics and probiotics in the future.