Guava pomace: a new source of anti-inflammatory and analgesic bioactives

Abstract

Background: Guava pomace is an example of the processing waste generated after the manufacturing process from the juice industry that could be a source of bioactives. Thus, the present investigation was carried out in order to evaluate the anti-inflammatory and antinociceptive potential and determinate the main phenolic compounds of a guava pomace extract (GPE).

Methods: The anti-inflammatory activity was evaluated by carrageenan, dextran, serotonin, histamine-induced paw edema and neutrophils migration in the peritoneal cavity models. Acetic acid-induced abdominal writhing and formalin test were performed to investigate the antinociceptive effects. In addition, the content of total phenolic and of individual phenolic compounds was determined by GC/MS.

Results: GPE showed anti-inflammatory activity by carrageenan, dextran, serotonin, histamine-induced paw edema and neutrophils migration in the peritoneal cavity models (p < 0.05). GPE also demonstrated antinociceptive activity by acetic acid-induced abdominal writhing and formalin test (p < 0.05). The total phenolic value was 3.40 ± 0.09 mg GAE/g and epicatechin, quercetin, myricetin, isovanilic and gallic acids were identified by GC/MS analysis.

Conclusions: The presence of bioactive phenolic compounds as well as important effects demonstrated in animal models suggest that guava pomace could be an interesting source of anti-inflammatory and analgesic substances.

Figure 1

Recruitment of neutrophils into the peritoneal cavity induced by carrageenan. Control (C) treated with vehicle, Indomethacin (Indo) and Guava Pomace Extract (GPE) were followed by carrageenan injection. Mean ± S.E.M., n = 5-6. The symbol (#) indicates statistical difference compared to the vehicle group. The symbol (*) indicates statistical difference compared to the carrageenan group (ANOVA followed by Tukey’s test, *p < 0.05 and **p < 0.01).

Figure 2

Effect of i.p. injection of guava pomace extract on abdominal constriction induced by acetic acid in mice. Control (C) treated with vehicle, Indomethacin (Indo) 10 mg/kg, Guava Pomace Extract (GPE). Mean ± S.E.M., n = 5-6. *p < 0.05 compared to the control group (ANOVA followed by Dunnett’s test).

Figure 3

Effect of i.p. injection of guava pomace extract on formalin-induced nociception in mice. Control (C), Indo (Indomethacin 10 mg/kg), Morph (Morphine 10 mg/kg), Guava Pomace Extract (GPE). Mean ± S.E.M., n = 5-6. *p < 0.05, **p < 0.01 and ***p < 0.001 compared to the control group (ANOVA followed by Dunnett’s test).