Recycling of Lycium barbarum by-products and bioactive substance application in silage - Insight into antioxidant activity and the regulation mechanism of anaerobic fermentation
Lycium barbarum, originating from East Asia, is a well-known traditional Chinese herbal medicine with significant medicinal and nutritional benefits. It has gained attention for its various bioactive compounds, such as Lycium barbarum polysaccharides (LBPs), flavonoids (FLA), betaine (BET), polyphenols, vitamins, and trace elements, which exhibit anti-tumor, anti-inflammatory, antioxidant, hypoglycemic, and hypolipidemic properties. The by-products of Lycium barbarum processing, known as Lycium barbarum by-products (LBB), including fruit residues and fruit stalks, are often discarded despite containing valuable nutrients and bioactive compounds. This wasteful practice not only leads to resource depletion and environmental pollution but also results in significant economic losses. Therefore, it is essential to enhance the efficiency of resource recycling and promote social sustainability by utilizing LBB effectively.LBB, LBP, FLA and BET improved fermentation quality by increasing the lactic acid (LA) content and reducing the pH values and ammonia nitrogen (NH3-N) content. They also enhanced nutrient quality by decreased the acid detergent fiber (ADF) content and increased the water-soluble carbohydrate (WSC) content. DM loss was significantly reduced in LBB-treated silages. The active components and LBB significantly affected the metabolite profiles of silage, with differential metabolites enriched in flavonoid biosynthesis, isoflavonoid biosynthesis, plant hormone signal transduction and flavone and flavonol biosynthesis. Integrated correlation analysis also provided a link between the high abundance microbiota and metabolites. Thus, these findings offer a new insight into utilizing LBB as an additive for improving silage quality of alfalfa.