Uvaia (Eugenia pyriformis Cambess) is a fruit tree native to the Atlantic Forest and that features peculiar aroma and flavor. Although this fruit is highly popular locally, its commercial farming is virtually nonexistent. In addition, limited studies on this fruit have been conducted. Therefore, the present study aimed to investigate the physical, chemical, and functional characteristics of two uvaia fruit populations grown in Salesópolis, SP, Brazil, in order to determine their potential for being consumed both in natura and processed. Uvaia fruits were evaluated as for skin color, whole fruit weight, longitudinal and transversal diameters, seed percentage, pulp yield, pulp firmness, pH, total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA ratio, total soluble sugars, soluble and total pectins, total carotenoids, yellow flavonoids, total phenolic compounds, ascorbic acid, and in vitro antioxidant capacity (DPPH and ORAC assays). The total mineral content was also determined. Comparison among the two populations revealed that uvaia fruits showed significantly different firmness values, large fruits showing suitable characteristics for the fresh fruit market. However, small fruits were sweeter and richer in antioxidants, allowing the consumption of both natural and processed fruits. Thus, this native fruit denotes an important source of nutrients and bioactive compounds, especially iron.

The Atlantic Forest is recognized as a biome rich in biodiversity. Cambuci trees (Campomanesia phaea) produce fruits that may be consumed as both fresh and processed forms but are still underutilized. The aim of this study was to describe the physicochemical characteristics and bioactive compounds in cambuci fruits from Brazilian Atlantic Forest, located at Natividade da Serra-SP, Brazil. Cambuci fruits of the fifty-nine accessions were characterized according to fresh weight, pulp yield, peel percentage, longitudinal and transversal diameters (LD and TD, respectively), pH, soluble solids content (SSC), titratable acidity (TA), SSC/TA ratio, ascorbic acid, total phenolic compounds content, and antioxidant activity using the DPPH assay. The soluble solids contents varied from 5.10 °Brix to 11.00 °Brix. The titratable acidity varied from 1.29 to 2.90 g citric acid 100 g-1. Ascorbic acid content was of 31.12 to 139.38 mg 100 g-1. Total phenolic compounds varied from 330.5 mg GAE 100 g-1 to 3,526.04 mg GAE 100 g-1. The antioxidant activity was of 65.03 µmol Trolox g-1 fruit pulp (fresh weight) to 199.78 µmol Trolox g-1 fruit pulp (fresh weight), a factor of 6.7 difference between the extremes. These results showed cambuci fruits presented as rich source of ascorbic acid, total phenolic compounds, and with high antioxidant capacity.

Pereskia aculeata Miller is a native cactaceae found from the Northeast to the South of Brazil. This plant is recognized by the high nutritional value of their leaves, which are the most used in cooking and folk medicine. However, studies on the chemical characteristics and antioxidant capacity of the ora-pro-nobis fruits are scarce. Therefore, the aim of this study was to determine the best harvest point of the ora-pro-nobis fruits to optimize the content of bioactive compounds and their antioxidant capacity. The fruits were manually harvested, defined by their peel colors in three maturity stages: unripe (green), intermediate (yellowish green), and ripe (yellow) stages. The following attributes were evaluated: soluble solids (SS), titratable acidity (TA), SS/TA ratio, pH, and content of bioactive compounds, such as total chlorophylls, carotenoids, yellow flavonoids, total phenolic compounds, and antioxidant capacity. There was a decrease in the content of chlorophyll followed by an increase in the of total carotenoids and yellow flavonoids, due to the maturity stage. For the total phenolic compounds, it was not observed significant difference between the stages. The antioxidant capacity was quantified by the ORAC method in lyophilized pulp in the unripe (1.95 mmol 100 g-1 trolox) and ripe (3.85 mmol 100 g-1 trolox) stages. The lowest contents were observed in the intermediate (0.80 mmol 100 g-1 trolox in lyophilized pulp) stage. The maturity stage significantly influenced the bioactive compounds of ora-pro-nobis, which presented higher values of total carotenoids, yellow flavonoids, and antioxidant capacity in ripe fruits.

The intake of fruits and vegetables rich in nutrients with bioactive properties is associated with the prevention of a range of chronic diseases such as cardiovascular diseases, diabetes, and cancer that originate from physiological disorders, which can be promoted by the accumulation of free radicals in the body. Several chemical compounds with bioactive functions are found in fruits and vegetables. Among these, phenolic compounds stand out for having high antioxidant capacity. These compounds originate from the secondary metabolism of plants, being essential for their growth and reproduction. In addition, they can be more expressed by plants under stress conditions, such as infections by microorganisms, lesions, severe climate changes, nutritional deficiency, among others. The highest concentrations of these phenols are found in fruit and vegetable skins, due to their potential use in protecting against UV rays, pathogens and predators. The search for new sources of natural and/or synthesized antioxidants has been growing due to the wide biological activity observed for these compounds, such as the inhibition of lipid oxidation and its action against the inactivation of free radicals. These compounds can be synthesized via the shikimate/phenylpropanoid pathway. It is believed that after consumption they are partially degraded in the small intestine, about 5 to 10%, and the rest in the large intestine. Here we review how the plant synthesizes phenolic compounds and their health effects, demonstrating the significant dietary activity of these compounds in metabolic processes.