ABSTRACT
Jujube contains abundant cyclic adenosine monophosphate (cAMP). In contrast, the extraction technology of cAMP from jujube is still to be explored. In this study, the ultra-high pressure extraction (UHPE) conditions for obtaining the maximum cAMP yield from jujube were optimized. Orthogonal array design (OAD) was applied to evaluate the effects of three variables (pressure, pressure-holding time, and liquid-to-solid ratio) by UHPE on cAMP yield. The results showed that the optimal cAMP yield (1223.2 µg/g) was derived at 300 MPa, 20 min duration, and a liquid-to-solid ratio of 2.5 ml/g. In addition, as an important functional ingredient in jujube, cAMP has potential anti-allergic effect. To develop the functional characteristics of jujube, the effect of cAMP was characterized in vivo with the Balb/c mouse model of peanut allergy, which was established by subcutaneous injection of crude peanut protein extract (PN). The results showed that treatment with cAMP in PN-sensitized mice suppressed the lesions in jejunal tissues and allergic symptoms and restored spleen index. Meanwhile, cAMP treatment reduced serum levels of specific immunoglobulin E (IgE), histamine, as well as interleukin-4 (IL-4) and stimulated the secretion of tumor necrosis factor-α (TNF-α), whereas the serum levels of interleukin-10 (IL-10) were not affected. Our results suggested that cAMP has an anti-allergic effect in PN-sensitized mice.
