Lycium barbarum, a homology of medicine and food, contains many active ingredients including polysaccharides, polyphenol, betaine, and carotenoids, which has health benefits and economic value. The bioactive components in Lycium barbarum exhibit the effects of antioxidation, immune regulation, hypoglycemic effects, and vision improvement. Recently, the development of nutrition and health products of Lycium barbarum has been paid more and more attention with the increase in health awareness. A variety of nutrients and bioactive components in wolfberry can be retained or increased using modern fermentation technology. Through fermentation, the products have better flavor and health function, which better meet the needs of market diversification. The main products related to wolfberry fermentation include wolfberry fruit wine, wolfberry fruit vinegar, and lactic acid fermented beverage. In this review, the mainly bioactive components of Lycium barbarum and its deep-processing products of fermentation were summarized and compared. It will provide reference for the research and development of fermented and healthy products of Lycium barbarum.

Wolfberry (Lycium barbarum L.), as a kind of functional fruit, has various nutritional and bioactive components, which exhibit healthy benefits. However, wolfberry is not easy to preserve, and the intensive processing of wolfberry needs to be developed. In the present study, the changes in the phytochemical and bioactive compounds, as well as the antioxidant properties of wolfberry, were evaluated in the brewed processes. We found that the sugar contents were significantly decreased, and the total acids values were significantly increased during the fermentation processes. The sugar and fat contents were low in the wolfberry fruit vinegar after fermentation, which is of benefit to human health. In addition, amino acids were examined during the fermentation processes, and histidine, proline, and alanine were found to be the main amino acids in vinegar. The total phenolics and flavonoids contents were significantly increased by 29.4% and 65.7% after fermentation. 4-Hydroxy benzoic acid, 3-hydroxy cinnamic acid, and chlorogenic acid were the primary polyphenols in the wolfberry fruit vinegar. Moreover, the antioxidant activity of wolfberry fruit vinegar was significantly increased compared with that of wolfberry fruit after the fermentation processes. Polysaccharides and polyphenolics were strongly correlated with the antioxidant activity during the fermentation processes. The findings suggest that wolfberry fruit vinegar has a high antioxidant capability, and could be a beneficial food in the human diet.

Wolfberry (Lycium barbarum L.) is a nutritious and medicinal fruit, and deeply processed products of wolfberry needs to be improved. In this study, nutrition, bioactive compounds, and hepaprotective activity were explored in wolfberry vinegar (WFV). The contents of nutrients including total sugar and protein in WFV samples were 2.46 and 0.27 g/100 mL, respectively. Total phenolic and flavonoid contents in WFV were 2.42 mg GAE/mL and 1.67 mg RE/mL, respectively. p-Hydroxybenzoic acid and m-hydroxycinnamic acid were the main polyphenols in WFV. The antioxidant activity of WFV were 20.176 mM Trolox/L (ABTS), 8.614 mM Trolox/L (FRAP), and 26.736 mM Trolox/L (DPPH), respectively. In addition, WFV treatment effectively alleviated liver injury by improving histopathological changes and reducing liver biochemical indexes in CCl4-treated mice. WFV alleviated oxidative damage by inhibiting oxidative levels and increasing antioxidant levels. These results suggest that WFV can be utilized as a functional food to prevent oxidative liver injury.

Wolfberry (Lycium barbarum L.) as a functional food is rich in nutrients and bioactive substances. However, the fresh wolfberry is difficult to preserve, and its deep-processing products are required to improve. In the present study, single-strain fermentation vinegar (SFV) and mixed-strain fermentation vinegar (MFV) were prepared, and the physicochemical, bioactive compounds, antioxidant capacities and volatile characteristics were examined to obtain an optimal method. The results showed that reducing sugar was sufficiently utilized during mixed-strain fermentation, and more acid substances were produced compared with single-strain fermentation. Meanwhile, total phenols content (2.64 ± 0.04 mg GAE/mL), total flavonoids content (1.81 ± 0.01 mg GAE/mL) and antioxidant activities in MFV were significantly increased compared with those in SFV. Rutin, p-hydroxycinnamic acid, and 4-hydroxybenzoic acid presented higher contents in MFV than those in SFV. The contents of total organic acids (88.13 ± 0.13 mg/mL) and total amino acids (6.50 ± 0.17 mg/mL) in MFV were significantly improved compared with those in SFV. Proline, alanine and serine were the top three amino acids in MFV. Moreover, acids, eaters, and alcohols were the pre-dominant volatile organic compounds in MFV, which were higher 9.49%, 55.27%, 18.72% in MFV than those in SFV, respectively. The results suggest that MFV efficiently enhances potential health benefits and flavor, which increases the economic value of wolfberry.

Wolfberry (Lycium barbarum L.), as a kind of combination of medicine and food, is rich in antioxidant components. However, the deep-processed products of wolfberry need to be developed to improve its added value. This study aimed to investigate the nutrients, active antioxidant ingredients, and liver-protective mechanism of mixed-culture fermented wolfberry vinegar (MFV). The results showed that MFV had significantly higher protein and significantly lower fat content than wolfberry juice before fermentation, indicating that MFV was a healthy product. The active ingredient content, which included total phenolics, total flavonoids, polysaccharides, betaine, and antioxidant activities, was significantly increased in MFV after mixed-culture fermentation. Moreover, MFV improved histopathological changes and reduced liver biochemical indicators in alcohol-treated mice, indicating the improvement of liver function. In addition, MFV effectively alleviated alcohol-induced liver injury by increasing the expression of alcohol metabolizing enzymes and inhibiting CYP2E1 activity. MFV regulated the equilibrium between pro-oxidant and antioxidant levels by downregulating pro-oxidant markers and upregulating antioxidant markers. Furthermore, MFV reduced the levels of inflammatory indexes by inhibiting the PI3K/Akt/NF-κB signaling pathway. These results suggest that MFV is a healthy food for liver protection, which provides a strategy for deep-processed products of wolfberry.