Finger citron is a medicinal and edible plant belonging to the Citrus genus in the Rutaceae family. It contains polysaccharides, essential oils, flavonoids, coumarins, dietary fiber and other bioactive components. The health benefits of finger citron mainly include antioxidant, anti-inflammatory, anti-tumor, anti-anxiety, anti-depression functions. This paper review recent findings of the bioactive components in finger citron and their health benefits and discusses the future prospects of microbial transformation, so as to offer guidance for the research, development and commercialization of functional foods based on finger citron.

Finger citron (Citrus medica ‘Fingered’) is a medicinal and edible plant belonging to the genus Citrus of the family Rutaceae. Finger citron grown in Guangdong is called Guang Foshou. The present study explored the in vitro hypoglycemic activity and mechanism of polysaccharides extracted from Guang Foshou by measuring enzyme activities as well as using cell model. The results showed that the half-maximal inhibitory concentrations (IC₅₀) of the polysaccharide fraction FCP-2-1 for α-glucosidase, α-amylase and angiotensin converting enzyme (ACE) were 2.74, 0.87 and 0.85 mg/mL, respectively. All the polysaccharides remarkably promoted glucose transport in 3T3-L1 adipocytes, improved lipid metabolism and reduced the secretion of tumor necrosis factor (TNF)-α. The mechanism might be that FCP-2-1 could promote the expression of phosphatidylinositol 3-kinase (PI3K), glucose transporter 4 (GLUT4), protein kinase B (PKB or AKT) and phosphorylated AKT (p-AKT) in the PI3K/AKT signaling pathway to alleviate insulin resistance and restore normal cellular metabolism.

This study aimed to compare the effects of optimal medium-high pressure coupled with heat treatment (OPH), optimal ultra-high pressure treatment (OP) and traditional two-stage heat treatment (H) on the quality characteristics of Nemipterus virgatus sausages during a refrigerated storage period of 60 days. During storage, changes in freshness indexes such as total bacterial count, total volatile basic nitrogen (TVB-N) content, thiobarbituric acid (TBA) value, pH and conductivity were determined as well as gel properties such as gel strength, water-holding capacity, whiteness and textural properties. The results showed that the total bacterial count, TVB-N content, TBA, conductivity and cooking loss of sausages increased gradually with storage time, while the sensory score, water-holding capacity, whiteness, gel strength, and textural properties progressively decreased. The pH increased first and then decreased. On the 60th day of refrigeration, TVB-N content was 14.04% and 27.12% lower and TBA value was 11.76% and 23.73% lower in the OPH treatment group than in the H and OP treatment groups, respectively. Additionally, the gel strengths of the H, OPH, and OP treatment groups were 2365.82, 3229.36 and 1905.53 g·cm, respectively, and their water-holding capacities were 71.25%, 74.03% and 68.86%, respectively. In summary, OPH treatment was able to better maintain the quality of fish sausages and slow down flavor changes during refrigerated storage.