A Critical Appraisal of the Most Recent Investigations on Ora-Pro-Nobis (Pereskia sp.): Economical, Botanical, Phytochemical, Nutritional, and Ethnopharmacological Aspects

Abstract

Pereskia aculeata Miller and Pereskia grandfolia Haw, known as 'ora-pro-nobis', are unconventional vegetables belonging to the Cactaceae family, native to the Americas and common in the northeast and southeast regions of Brazil. This review attempts to present a balanced account of both the methods used for obtaining extracts from the diverse parts of the plants and the results that were obtained in terms of their applicability to foods and other products with biological activities. Attention will also be devoted to the properties of their bioactives and their applications to real food products. Methods for obtaining extracts from the diverse parts of the plants will be analyzed, as well as the chemical nature of the bioactives that were hitherto identified. Next, the applicability of ora-pro-nobis in either its integral form or in the form of extracts or other products (mucilages) to the production of food and dietary supplements will be analyzed. The species have been extensively investigated during the last few decades. But, the determination of chemical structures is frequently incomplete and there is a need for new studies on texture determination and color evaluation. Further studies exploring the fruit and flowers of P. aculeata are also required.

Keywords: bioactive properties; essential oils; extract; extraction methods; foods; mucilage; polyphenols; polysaccharide; protein; terpenoids.

Figure 1

Number of published papers found under the keywords “Pereskia AND aculeata” or “Pereskia AND grandifolia” by year since 1950 (Scopus).

Figure 2

Pereskia aculeata Miller (A); flower and leaves; (B) fruit (C); Pereskia grandifolia Haw (D); flower and leaves (E); fruit (F).

Figure 3

Some structural features described for the polysaccharide found in the mucilage of Pereskia aculeata leaves [93,94]. Ara = arabinose; Gal = galactose; GalU = galactouronic acid; Rha = rhamnose; the subscripts p and f denote the pyranosyl and furanosyl forms, respectively.

Figure 4

Representative structures of polyphenolic compounds found in ora-pro-nobis in addition to the phenylethylamine alkaloid hordenine.

Figure 5

Structural features of caffeoyl hexaric acid and coumaroyl hexaric acid reported to occur in a hydroalcoholic extract from P. aculeata, highlighting the uncertainty about the hydroxyls of hexaric acid involved in the formation of the ester linkage [73].

Figure 6

Structures of the most abundant molecular components of the essential oil fraction of the aerial parts of P. aculeata [9].