Hepatoprotective effects of ethnic cabbage dishes: a comparison study on kimchi and pao cai

Abstract

Consuming ethnic vegetable dishes, that has been an integral part in the food culture of many countries, is suggested to bring health benefits to humans. Kimchi from Korea and pao cai from China are two distinct vegetable dishes made from Chinese cabbage (Brassica rapa) through different processes. While kimchi is a fermented food, pao cai is produced by pickling in brine or vinegar. The present study aimed to investigate and compare the hepatoprotective effects of kimchi and pao cai in vivo using animal model and in vitro using a cell line. Despite having similar nutritional profiles, kimchi and pao cai exhibited different chemical and microbiological properties. Compared to pao cai, the pH during fermentation of kimchi dropped more rapidly and the antioxidant activity of kimchi was also stronger. In addition, total microorganisms and lactic acid bacteria were consistently higher in kimchi than in pao cai. In vivo, the hepatoprotective properties of kimchi and pao cai were associated with the increase in expression and activity of major liver antioxidant enzymes, particularly glutathione reductase, glutathione peroxidase, glutathione S-transferase, catalase, and superoxide dismutase. In vitro, both kimchi and pao cai promoted the formation of glutathione. Upon exposure to chemically induced oxidative stress, kimchi protected liver cells by inhibiting glutathione depletion and limiting lipid peroxidation. In general, kimchi demonstrated stronger hepatoprotective properties compared to pao cai. Thus, the present study provides promising insights into the development of ethnic foods, particularly kimchi and pao cai, as functional foods beneficial for human health.