Introduction: Currently, the anti-oxidation of active ingredients in mulberry leaves (MLs) and their forage utilization is receiving increasing attention. Here, we propose that MLs supplementation improves oxidative resistance and immunity.Methods: We conducted a trial including three groups of growing mutton sheep, each receiving fermented mulberry leaves (FMLs) feeding, dried mulberry leaves (DMLs) feeding or normal control feeding without MLs.Results: Transcriptomic and metabolomic analyses revealed that promoting anti-oxidation and enhancing disease resistance of MLs is attributed to improved tryptophan metabolic pathways and reduced peroxidation of polyunsaturated fatty acids (PUFAs). Furthermore, immunity was markedly increased after FMLs treatment by regulating glycolysis and mannose-6-phosphate pathways. Additionally, there was better average daily gain in the MLs treatment groups.Conclusion: These findings provide new insights for understanding the beneficial effects of MLs in animal husbandry and provide a theoretical support for extensive application of MLs in improving nutrition and health care values.

Mulberry, an important woody tree, has strong tolerance to environmental stresses, including salinity, drought, and heavy metal stress. However, the current research on mulberry resistance focuses mainly on the selection of resistant resources and the determination of physiological indicators. In order to clarify the molecular mechanism of salt tolerance in mulberry, the physiological changes and proteomic profiles were comprehensively analyzed in salt-tolerant (Jisang3) and salt-sensitive (Guisangyou12) mulberry varieties. After salt treatment, the malondialdehyde (MDA) content and proline content were significantly increased compared to control, and the MDA and proline content in G12 was significantly lower than in Jisang3 under salt stress. The calcium content was significantly reduced in the salt-sensitive mulberry varieties Guisangyou12 (G12), while sodium content was significantly increased in both mulberry varieties. Although the Jisang3 is salt-tolerant, salt stress caused more reductions of photosynthetic rate in Jisang3 than Guisangyou12. Using tandem mass tags (TMT)-based proteomics, the changes of mulberry proteome levels were analyzed in salt-tolerant and salt-sensitive mulberry varieties under salt stress. Combined with GO and KEGG databases, the differentially expressed proteins were significantly enriched in the GO terms of amino acid transport and metabolism and posttranslational modification, protein turnover up-classified in Guisangyou12 while down-classified in Jisang3. Through the comparison of proteomic level, we identified the phenylpropanoid biosynthesis may play an important role in salt tolerance of mulberry. We clarified the molecular mechanism of mulberry salt tolerance, which is of great significance for the selection of excellent candidate genes for saline-alkali soil management and mulberry stress resistance genetic engineering.

Mulberry leaves (ML) are a promising alternative fodder source due to their high protein content and the abundance of active components. A test of three inoculants in various combinations revealed that high-quality ML silage was produced at an inoculum ratio of 1:1:0 (50% Saccharomyces cerevisiae, 50% Lactobacillus plantarum, and 0% Bacillus subtilis). Using dry matter (DM) loss, pH, ammonia-N and amino acid contents, total antioxidant activity, and total flavonoids content to evaluate silage quality, this inoculant mixture was shown to produce high-quality silage within a range of inoculum size (5–15%), moisture contents (50–67%), ensiling temperatures (27–30°C), and ensiling duration (14–30 days). A third trial comparing silages produced after 30 days at 28°C and 50% moisture content revealed that silage E, prepared using an L. plantarum inoculant alone, displayed the lowest DM loss and pH, and low bacterial diversity, and it was dominated by Lactobacillus (88.6%), with low abundance of Enterobacter (6.17%). In contrast, silage B5, prepared with equal ratios of L. plantarum and S. cerevisiae, was dominated by Enterococcus (67.16%) and Lactobacillus (26.94%), with less marked yeast persistence, and reducing the DM content from 50 to 40% altered these relative abundances to 5.47 and 60.61, respectively. Control silages produced without an inoculant had the highest pH and ammonia-N content (indicative of poor quality), had the lowest antioxidant activity, had higher bacterial diversity, and were dominated by Carnobacterium (74.28%) and Enterococcus (17.3%). In summary, ensiling of ML conditions with proper inoculants yielded high-quality silage with a favorable microbial community composition.

The mulberry fruit is prized for its superior nutrition value and abundant color due to its high flavone content. To enhance comprehension of flavone biogenesis induced by external hormones, we sprayed exogenous ethylene (ETH), indoleacetic acid (IAA) and spermine (SPM) on mulberry fruit (Hongguo 2) during its color-changed period. The levels of anthocyanin, titratable acid, soluble sugar and endogenous hormones were determined after hormone treatment, integrated transcriptome and metabolome analysis were performed for mechanism exploration. Our results indicated that exogenous ETH, SPM, and IAA play important roles in mulberry ripening, including acid reduction, sugar increase and flavonoid synthesis.

Mulberry leaves (MLs) are an unconventional feed with fiber and various active ingredients, and are acknowledged as likely to regulate lipid metabolism, while the molecular mechanism remains undefined. Therefore, our objective was to define the role of MLs on the overall lipid metabolism. We conducted a feeding experiment of three groups on growing mutton sheep fed with dried mulberry leaves (DMLs), with fermented mulberry leaves (FMLs), or without MLs (as control). Analyses of transcriptome and widely target lipids demonstrated the addition of MLs triggered big perturbations in genes and metabolites related to glycerolipid, phospholipid, ether lipid, and sphingolipid metabolism. Additionally, the variations of the above lipids in the treatment of MLs possibly facilitate immunity enhancement of growing mutton sheep via the activation of complement and coagulation cascades. Furthermore, treatments with MLs could expedite proceedings of lipid degradation and fatty acid β oxidation in mitochondria, thereby to achieve the effect of lipid reduction. Besides, added DMLs also fuel fatty acid β-oxidation in peroxisomes and own much stronger lipolysis than added FMLs, possibly attributed to high fiber content in DMLs. These findings establish the novel lipid-lowering role and immune protection of MLs, which lays the foundation for the medicinal application of MLs. Mulberry leaves (MLs) are rich in a wide variety of active ingredients and are also a kind of traditional Chinese medicine with the same origin as medicine and food. Previous studies have found that MLs may regulate lipid metabolism. But the exact mechanism remains unclear. Our study reveals that ML supplement not only alters lipid metabolism including glycerol phospholipid, ether lipid as well as sphingolipid metabolism, which may help to improve immunity but also promote fatty acid degradation as well as β oxidation to achieve the effect of fat reduction.

Mulberry leaves, a traditional Chinese medicine with the values of medicine and food, are rich in various active ingredients and nutrients. Gastrointestinal bacteria are recognized to play a crucial role in food digestion, nutrient metabolism and the host immune health. However, the modulations of mulberry leaves on microbiota and metabolites remain insufficiently understood. In this study, a feeding experiment was conducted involving three groups on growing mutton sheep: one fed with dried mulberry leaves, another with fermented mulberry leaves and one without mulberry leaves (as control), afterwards, 16s sequencing of ruminal and fecal microbiota was performed. The present study revealed that the addition of mulberry leaves significantly modifies rumen bacterial community and promote the production of volatile fatty acids, which in turn promotes rumen digestion and metabolism of growing mutton sheep to ensure the supply of nutrients and promote immune health. Furthermore, mulberry leaves supplementation helps regulate the fecal microbial community and reduce the emission of odorous gas (hydrogen sulfide and harmful Benzene, 1, 2, 3, 5-tetramethyl). Unexpectedly, feeding with fermented mulberry leaves could reduce the emission of fecal smelly or harmful volatile gas (ammonia nitrogen, 3-methyl indole, p-Cresol and DL-Lactamide, propyl ether) which is caused by the immediate supplementation with dried mulberry leaves. The present study revealed that added mulberry leaves could promote absorption of animal’s nutrients and immune health. Furthermore, the addition of mulberry leaves, especially fermented mulberry leaves, contributed to the optimization of the livestock environment and strengthen environmental protection. These findings provide valuable insights into the potential applications of mulberry leaves as forage in animal husbandry.