Evaluation of antioxidant capacity, genotoxicity and polyphenol content of non conventional foods: Prosopis flour

Fruits such as Prosopis pod have been food sources (patay, arrope, chicha or aloja) of inhabitants of arid and semi-arid lands in South America. The aims of the present study were determine some nutritional and functional properties as well as genotoxicity of flour obtained from Prosopis ripe pods that were submitted to different processing. Sucrose constituted the main sugar for flours obtained from Prosopis alba and Prosopis nigra. Decoctions and macerations showed around 2.9% and 1.4% of soluble proteins, respectively. The highest free phenolics, flavonoids and condensed tannins contents were observed in aqueous extractions with heating. None of the samples presented phytic acid levels high enough to constitute a nutritional problem. Antioxidant activity (AA) was evaluated by DPPH, ABTS and β-carotene bleaching assays. Results showed that the antioxidant potential was significantly higher in flour obtained from P. nigra pods than in that from P. alba pods, and it was also higher in aqueous extracts than in alcoholic ones. Data obtained suggests that compounds responsible for AA are thermostable; therefore, Prosopis flour might be capable of retaining a significant amount of antioxidant capacity after heating. Prosopis extracts did not show any mutagenic effect with and without metabolic activation. Prosopis flour proved to be a non conventional, novel and rich source of antioxidant compounds that could help to prevent pathologies associated with oxidative stress.