Influence of post-harvest treatments and solvent extraction on antioxidants potential, enzymes inhibitions activities and phytochemical content of Pouteria campechiana (Kunth) Baehni nuts (underutilized crops)

Abstract The nuts of Pouteria campechiana (Kunth) Baehni belong to the unconventional sources of nutrients of plant origin and are therefore considered as waste. Its use as a substitute in various formulations would require prior treatments that would affect its various biological properties. Therefore, the present study revealed the in vitro antioxidant and anti-diabetic potential and the secondary metabolite content of Pouteria campechiana nuts subjected to different cooking treatments. After harvesting, the nuts were divided into four different batches: the first was used as a control, the second was roasted, the third was boiled and the last was boiled and then roasted. Ethanolic and hydroethanolic extracts were made of these different samples and the content of secondary metabolites, antioxidant and anti-diabetic potential were determined. These analyses showed that the phenolic content was significantly ( p < 0.05 ) lower when the extraction was carried out with ethanol, whereas the opposite was observed with hydroethanolic extraction. The flavonoid content ranged from 9.89 (untreated) to 17.58 (boiled) mg CE/g extract and from 8.51 (roasted) to 16.20 (boiled) mg CE/g extract for ethanolic and hydroethanolic extracts, respectively. The type of solvent had a significant effect ( p < 0.05 ) on the flavonoid content of the roasted sample. The reducing capacity of the Fe 3+ ion was better with the hydroethanolic extracts, especially with the control sample. The hydroethanolic extract of the boiled-roasted sample was better at reducing the DPPH radical. In vitro anti-diabetic tests showed that 60–70% of the alpha-amylase activity was inhibited by the ethanolic extract of the boiled-roasted sample. Amyloglucosidase activity was further reduced by the hydroethanolic extract of the untreated sample at a concentration of 100 µg/mL. These results confirm the value of this under-utilized nut and provide the pharmaceutical industry with information on the nature of the compounds present according to the different treatments. Graphical Abstract