Abstract
Kurozu is a brewed rice vinegar prepared by a traditional method in Kagoshima prefecture, Japan, and is regarded as a healthful food. The effects of the non-volatile components obtained from Kurozu (the residue of Kurozu) on the primary monolayer culture of rat hepatocytes were examined. In serum-free L-15 medium supplemented with the residue of Kurozu, about 60% of the hepatocytes inoculated to a dish survived for 6 days of culture. In contrast, without the residue, the number of hepatocytes decreased to less than one-third of the inoculated cells during the culture. The amount of albumin secreted in the medium was monitored as an expression of liver-specific function. In the medium with the residue of Kurozu, the rat hepatocytes secreted a considerable amount of albumin in 4-day culture (2.5 μg/ml medium/24 h), and even at 6 days (1.3 μg/ml medium/24 h), while albumin secretion by the hepatocytes cultured without the residue decreased rapidly with time. These results suggest that some components in Kurozu residue are effective to maintain the primary culture of rat hepatocytes and thus for albumin production by the hepatocytes.
