The antioxidant properties of the cherimoya (Annona cherimola) fruit Gaytri Gupta-Elera, Andrew R. Garrett, Andres Martinez, Richard A. Robison, Kim L. O'Neill ⁎ Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT, USA, 84602 abstract article info Article history: Received 15 September 2010 Accepted 21 October 2010 Keywords: Cherimoya Antioxidant Oxidative stress AAPH ORAC Reactive oxygen species Annona cherimola is an exotic fruit from the genus Annona, native to the Andean highlands in western South America. The cherimoya skin, flesh and juice were isolated and analyzed for antioxidant content using the oxygen radical absorbance capacity (ORAC) assay. The juice showed the highest antioxidant activity, while the flesh exhibited the lowest. The cherimoya skin, flesh and juice extracts were also incubated with Raji (Burkitt's Lymphoma) and HT-29 (colon cancer) cell lines, and the antioxidant uptake of cells was measured. Both cell lines, when subjected to cherimoya juice, showed the highest antioxidant uptake. The cells were then exposed to AAPH, a radical initiator, to simulate the conditions of cells under oxidative stress, and then subjected to cherimoya skin, flesh and juice extracts. Both cell lines absorbed more antioxidants after being pre-exposed to AAPH, indicating that cells under stress have the ability to import antioxidants. © 2010 Elsevier Ltd. All rights reserved. 1. Introduction Annona cherimola, commonly known as cherimoya, is a species of fruit found in different subtropical areas around the world, mainly in northern Peru and southern Ecuador. Cherimoya is known to have been cultivated during the times of the Incan Empire, dating back to 1200 BC. Anthropological evidence suggests that the cherimoya fruit was an active ingredient in the Incan diet (Bonavia, Ochoa, Tovar, & Palomino, 2004). The cherimoya fruit is known for its exceptional taste, its use in traditional medicine as an antimicrobial and insecticide, and as an effective treatment for digestive disorders such as stomachache and pancreatic ulcers (Amoo, Emenike, & Akpambang, 2008). Considerable evidence suggests that oxidative stress leads to the development of conditions such as cancer and heart disease the two leading causes of death in the United States (Tribble & Frank, 1994; Xu, Kochanek, Murphy, & Tejada-Vera, 2010). Oxidative stress occurs when the production of reactive oxygen species (ROS) exceeds antioxidant capacity, which leads to oxidative damage. Partially reduced forms of oxygen, such as superoxide and hydrogen peroxide, that are produced during aerobic metabolism have the potential of causing oxidative injury to macromolecules such as nucleic acids, proteins and lipids. Oxygen radicals are capable of initiating radical chain-reactions that propagate oxidative injury (O'Neill, Standage, Hughes, & Murray, 2001). DNA damage is an early event in carcinogenesis, and oxidation is known to induce 2′-4′-oxidative DNA damage which may lead to the formation of DNA–protein cross-links, alterations in the carbohydrate-phosphate backbone, or direct modification of purine and pyrimidine bases. Tumors may develop if alterations in DNA lead to the activation of oncogenes or the inactivation of tumor suppressor genes. Dietary antioxidants found in bioactive food components exert regulatory effects on cell proliferation and cytotoxicity. Antioxidants such as vitamin C, vitamin E, soy sterols, and polyphenols help protect the cell against oxidant-induced proliferation, lipid peroxidation, glutathione peroxidase activation (Garcia-Alonso, Ros, & Periago, 2006; Ou, Huang, Hampsch-Woodill, Flanagan, & Deemer, 2002), and also contribute to thyroid regulation and glucose homeostasis (Panda, Kar, & Patil, 2009). Evidence indicates that A. cherimola is rich in antioxidants such as vitamins A and C, making it a beneficial health supplement (Garcia, Zepeda-Vallejo, Gallegos, Gonzales, & Madrigal, 2008). Interest in this fruit has also risen due to its high concentration of acetogenins, which are polyketides that act as secondary metabolites in plants. Research has accredited beneficial effects to acetogenins, including the induction of cytotoxic, anti-inflammatory and anti- tumorous activities, particularly in mammary, pancreatic, prostatic, and colon cancer cells (Chen, Chang, Chiu, Wu, & Wu, 1999). Analysis of twelve acetogenins in Annona cornifolia, a fruit related to A. cherimola, revealed through DPPH radical-scavenging activity that acetogenins contain antioxidant capacity, comparable to that of ascorbic acid (Santos Lima, Pimenta, & Boaventura, 2010). Acetogenins are thought to exert their effects through the inhibition of the ubiquinone oxido-reductase complex in the mitochondrial electron transport chain and the inhibition of NADH oxidase in the plasma membrane. Acetogenins contained in the stems of A. cherimola (Chen et al., 1999) and the seeds of Annona reticulata (Chen, Chang, Chiu, Wu, & Wu, 1998) have been isolated and identified, however, antioxidant properties of these Food Research International 44 (2011) 2205–2209 Abbreviations: AAPH, 2,2′-azobis(2-aminidopropane) dihydrochloride; ORAC, oxygen radical absorbance capacity; PBS, phosphate buffered saline; ROS, reactive oxygen species; RPMI, Roswell Park Memorial Institute; TE, Trolox Equivalents; AUC, area under the curve. ⁎ Corresponding author. 855 WIDB, Brigham Young University, Provo, UT 84602, USA. Tel.: +1 801 422 2449; fax: +1 801 422 0519. E-mail address: kim_oneill@byu.edu (K.L. O'Neill). 0963-9969/$ – see front matter © 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.foodres.2010.10.038 Contents lists available at ScienceDirect Food Research International journal homepage: www.elsevier.com/locate/foodres