Thermal drying is a common process used in the food industry for the modification of agricultural products. However, while various studies have investigated the alteration in physiochemical properties and chemical composition after drying, research focusing on the relationship between different dehydration conditions and bioactivity is scarce. In the current study, we prepared dried ginger under nine different conditions by varying the processing time and temperature and compared their immunomodulatory effects. Interestingly, depending on the drying condition, there were significant differences in the immune-stimulating activity of the dried ginger samples. Gingers processed at 50oC 1h displayed the strongest activation of macrophages measured by TNF-α and IL-6 levels, whereas, freeze-dried or 70oC- and 90oC-dried ginger showed little effect. Similar results were recapitulated in primary bone marrow-derived macrophages, further confirming that different dehydration conditions can cause significant differences in the immune-stimulating activity of ginger. Induction of ERK, p38, and JNK signaling was found to be the major underlying molecular mechanism responsible for the immunomodulatory effect of ginger. These results highlight the potential to improve the bioactivity of functional foods by selectively controlling processing conditions.
Bibliographical noteFunding Information:
This work was funded by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (NRF-2017R1C1B1006072) to Sanguine Byun and was supported by the High Value-added Food Technology Development Program (118059-02), funded by iPET (Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries) to Seokwon Lim.
All Science Journal Classification (ASJC) codes
- Applied Microbiology and Biotechnology