European consumers have a growing interest in new fruits and flavours, which has promoted the production and commercialization of exotic fruits such as goldenberry (Physalis peruviana L., Fam. Solanaceae). Colombia and South Africa are currently the main producers of this fruit, but it can be cultivated in almost all the highlands of the tropics and in several parts of the subtropics given its ability to adapt to a wide range of agroecological conditions [1]. The consumers demand for this small orange berry has also been driven by its nutritional value and health-promoting effects [2]. Although there are different studies about this fruit, the available information is still scarce. Furthermore, the fruit quality attributes can vary depending on the agricultural practices and edaphoclimatic conditions of the growing sites. Therefore, this study was carried out to evaluate the nutritional composition and the in vitro antioxidant and antimicrobial activity of goldenberry cultivated in the Northeast region of Portugal. Goldenberry samples were lyophilized and analysed for their proximate composition (moisture, protein, fat, ash, dietary fibre, and carbohydrates) following official methods of food analysis [3]. The profiles in sugars, organic acids, fatty acids, and tocopherols were characterized by standardized chromatographic methods [3]. The powdered goldenberry sample was also prepared in a hydroethanolic extract used for the evaluation of antioxidant activity (by oxidative haemolysis and lipid peroxidation inhibition assays) and antimicrobial effects against foodborne bacteria and fungi (by serial microdilution methods) [3]. The nutritional analysis revealed high levels of proteins and carbohydrates (manly fructose and glucose) and a lipid fraction consisting mainly of polyunsaturated fatty acids. Citric and ascorbic acids were detected in high amounts, as well as the four tocopherol isoforms. The hydroethanolic berry extract showed capacity for inhibiting haemolytic oxidation and lipid peroxidation, antibacterial effects against Staphylococcus aureus and Bacillus cereus, and antifungal activity against Aspergillus and Penicillium strains. Overall, this work highlighted the nutritional value of goldenberry, which has been pointed out as a functional fruit with a growing expression in the Portuguese market.
Keywords: nutritional value, functional food, sugars/acids, tocopherols, antioxidant, antimicrobial activity.
Acknowledgements:
The authors are grateful to Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); to FCT for the J. Pinela (CEECIND/01011/2018) and L. Barros contracts through the individual and institutional scientific employment program-contract, respectively, and for the M. Añibarro-Ortega studentship (2020.06297.BD); to MICINN for supporting the Ramón y Cajal grant of M.A. Prieto; to FEDER-Interreg España-Portugal programme for financial support through project TRANSCoLAB 0612_TRANS_CO_LAB_2_P; and to the Serbian Ministry of Education, Science and Technological Development for financial support [Contract No. 451-03-9/2021-14/200007].
To the University of Vigo for the mobility aid of the university research staff.
References
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- Ramadan, M. ., Food Res. Int., 44 (2011) 1830–1836.
- Añibarro-Ortega, M.., Pinela, J., Barros, L., et al., Antioxidants, 8 (2019) 444.
