Effect of the native polysaccharide of cashew-nut tree gum exudate on murine peritoneal macrophage modulatory activities

•Cashew nut tree gum exudate (CNTG) was identified as an acidic arabinogalactan.•CNTG-AGP fraction was previously identified as the arabinogalactan-protein component.•Both CNTG and CNTG-AGP increased the production of IL10.•Cells simultaneously stimulated by LPS and CNTG showed decreased in the levels of IFN-γ.•The in vitro screening anti-inflammatory tests of CNTG activity were promising. The native polysaccharide of cashew-nut tree gum exudate (CNTG) and its arabinogalactan-protein component (CNTG-AGP) were tested by using immuno-stimulant and anti-inflammatory in vitro assays of murine peritoneal macrophage activities. In the assay for immuno-stimulant activity (without previous treatment with lipopolysaccharide; LPS), CNTG increased the production of interleukin (IL)-10 and both CNTG and CNTG-AGP decreased the concentrations of IL6. When the macrophages were incubated in the presence of LPS and CNTG a decrease in the levels of nitric oxide (NO·) and IFN-γ was observed. The results could explain the popular use of CNTG as an anti-inflammatory. In addition, CNTG is the main component of the cashew-nut tree gum exudate, which has been considered a versatile polymer with potential pharmaceutical and food industry applications. These data may contribute to the study of the immunomodulation activity of plant polysaccharides, as well as encourage future experiments in the field of cashew-nut tree gum exudate applications.