Abstract

Vinegars are aqueous products of fermentation that are composed of acetic acid, water and other trace chemical components. Previous studies have shown that they have several beneficial effects for humans, such as anti-diabetic, anti-bacteria, antioxidant, anti-tumor or the enhancement of immune function. Nypa fruticans palm vinegar (NPV) is 1 of the vinegars that is usually used as a food ingredient. However, there are limited studies that have provided results to support its proposed immunomodulatory properties. This study investigated the immunomodulatory effects of NPV. Locally produced NPV from 3 different planting areas (fresh, brackish and saline water) of the Nakhon Si Thammarat province in Thailand were administered to rats, and the enhancement of the in vitro phagocytic activity was assessed. The results showed that NPV potently enhanced antibody production and the phagocytic activity. Moreover, NPV-treated rats showed a reduction of edema in type 4 hypersensitivity reactions. The results indicated that NPV had immunomodulatory effects, and therefore, NPV could be considered a functional food.