Antioxidant content in guava (Psidium guajava) and araçá (Psidium spp.) germplasm from different Brazilian regions Luiz Claudio Corrêa1, Carlos Antonio F. Santos2, Fabio Vianello3 and Giuseppina Pace P. Lima1* 1Department of Chemistry and Biochemistry, I.B., Universidade Estadual Paulista (UNESP), CP 510, CEP 18618-000 Botucatu, Sao Paulo, Brazil, 2Laboratório de Genética Vegetal, Embrapa Semi-Árido, Petrolina, Pernambuco, Brazil and 3Department of Biological Chemistry, University of Padova, Padova, Italy Received 3 August 2010; Accepted 23 December 2010 – First published online 31 May 2011 Abstract Guava (Psidium guajava) and araçá (Psidium spp.) plants are important for the Brazilian economy, as their fruit is both accepted by the consumers, and makes a beneficial contribution to the human diet thanks to their content in vitamin C, carotenoids and phenolic compounds. Here, we report the content in the fruit of free ascorbic acid, lycopene, b-carotene, flavonoids and phenolic compounds, and the total antioxidant activity present in a collection of guava and araçá accessions curated at the Embrapa Semiarido germplasm bank. Guava fruits with a red-coloured pulp flesh contained a significant amount of carotenoids, especially lycopene, and a high concentration of phenolic compounds. These compounds were largely responsible for the antioxidant activity of the araçá accessions. Among the guava accessions, phenolic compounds were also responsible for the antioxidant activity. High levels of free ascorbic acid were present in most accessions. In both guava and araçá, there is substantial potential to develop cultivars with a good level of consumer acceptability. Keywords: antioxidants; germplasm bank; plant breeding; Psidium spp. Introduction Guava (Psidium guajava) and araçá plants belong to the Myrtaceae family, comprising about 130 genera and 3000 species of trees and bushes, distributed mainly in the tropical and subtropical regions (Watson and Dallwits, 2008). The guava plant, native to the northern part of South America, is widely distributed in the tropical areas of America (Risterucci et al., 2005), and it is gaining visibility in the agro-food business due to the attractive characteristics of the fruit, such as flavour, appearance and health properties of nutrients and functional elements. It can be consumed fresh or processed forms, which include candies, jellies, compotes and juices. Araçá is a wild plant occurring throughout Brazil, and its fruits are particularly rich in minerals and functional elements such as vitamins and phenolic compounds (Caldeira et al., 2004; Wille et al., 2004). As its fruit is well accepted by consumers, it has been proposed as an alternative for commercial planting in specific areas (Franzon, 2009). The search for plants, which produce edible fruit containing substantial concentrations of functional com- pounds, has become one of the major priorities of crop breeding programmes (Carvalho et al., 2006). The aim is to obtain cultivars of native or even newly domesti- cated plants, adapted to fit the requirements of com- merce. Active Germplasm Banks (AGBs) are a potent tool for this purpose, particularly as they serve as a source of novel crop plants (Pereira, 1995). Functional* Corresponding author. E-mail: gpplima@ibb.unesp.br q NIAB 2011 ISSN 1479-2621 Plant Genetic Resources: Characterization and Utilization (2011) 9(3); 384–391 doi:10.1017/S1479262111000025 compounds, being considered in breeding programmes aimed at improving human diets are antioxidants such as vitamin C, carotenoids and phenolics (Chorilli et al., 2007). All of these are known to be active as neutralizers of free radicals, and are beneficial to human health (Indap et al., 2006). Vitamin C, for instance, helps to prevent DNA damage caused by free radicals, and reduces their harmful effects on plasma lipoproteins (Lehr et al., 1995). Carotenoids, which are responsible for the yellow/orange pigmentation in the plant (Mattiuz and Durigan, 2001), are also considered to be excellent antioxidants; in particular, guava fruit contains lycopene, a carotenoid able to prevent prostate cancer and athero- sclerosis (Rao and Agarwal, 2000). Phenolic compounds combine the trapping of free radicals with being able to chelate heavy metals (Shahidi et al., 1992). A common class of plant phenolics is represented by flavonoids, which are active as anti-microbial, anti-mutagenesis and anti-carcinogenesis agents (Martinez-Flores et al., 2002). The presence of antioxidants in guava has been pre- viously documented (Yan et al., 2006; Mendonça et al., 2007; Patthamakanokporn et al., 2008). A common theme in this research has been the quantification of free ascorbic acid (AA), phenolic compounds, caroten- oids and global antioxidant activity. The aim of the pre- sent study was to determine the content, in guava and araçá accessions curated by the Embrapa Semiárido AGB, of free AA, lycopene, b-carotene, total phenolics and total flavonoids, and to quantify their global antioxi- dant activity. This AGB is responsible for the collection and curation of plant species in the Amazonas (Amazonas and Rondônia), Caatinga (Bahia, Pernambuco, Piauı́ and Sergipe) and Maranhão provinces. Our goal is to support the breeding programme of Psidium spp., focusing on cultivars producing fruits with a high content of functional compounds. Materials and methods Samples acquisition Fruits were collected at physiological maturity from 60 guava and from 10 araçá accessions from the Psidium AGB (Table 1) installed in the Bebedouro experimental station of Embrapa Semiárido (98 90 latitude South and 408 290 longitude West, altitude 365.5 m) (Amorim Neto, 1989). For each accession, fruits from six plants were used, which were divided into three lots of two plants, account- ing for three repetitions. The material was processed, sieved to separate the seeds, frozen in liquid nitrogen and stored in a freezer (2808C) for the analyses, except for free AA determination, which was carried out immediately (Table 1). Free AA was determined according to Carvalho et al. (1990). The method is based on the reduction of the 2.6-dichlorophenol-indophenol (DCIP) by AA. The extraction was accomplished on about 500 mg of the processed material with 50 ml 0.5% oxalic acid. The extract was titrated with 0.02% DCIP, previously standar- dized with a solution of 50 mg/l AA, prepared in 0.5% oxalic acid. Results were expressed in mg of AA/100 g fresh weight (F.W). Lycopene and b-carotene concentrations were deter- mined according to the method used by Nagata and Yamashita (1992). Extractions were carried out on the processed material (0.5–2.0 g) with 20 ml hexane– acetone mixture (6:4). After agitation in ice for 15 min with a Turrax homogenizer (Germany) at 12,500 rpm, plant material was centrifuged at 6500 rpm for 10 min at 48C. The volume was adjusted to 20 ml with the extrac- tion mixture, and the final sample was read by a spectro- photometer at 453, 505, 645 and 663 nm, against a control constituted of the extraction mixture. The following equations were used for calculation: b-Carotene ðmg=100mlÞ ¼ 0:216£A663 2 1:22£A645 2 0:304£A505 þ 0:452£A453: Lycopene ðmg=100mlÞ ¼20:0458£A663 þ 0:204£A645 þ 0:372£A505 2 0:0806£A453: The results were expressed as mg/100 g F.W. Total phenolics were extracted according to the method proposed by Alothman et al. (2009), with minor modifications. Processed material (500 mg) was extracted with 90% ethanol (3 ml), followed by an extrac- tion with 50% acetone (3 ml). The extracted solutions were agitated, in an ice bath, for 30 min in the dark. After the first centrifugation at 6500 rpm for 15 min at 48C, the supernatant was removed and pooled. The pro- cess was repeated twice, and the volume was adjusted to 10 ml. Total phenolics were determined according to the method proposed by Singleton and Rossi (1965), using the Folin–Ciocalteu reagent. A calibration curve was built using gallic acid (GA) as standard. Spectrophoto- metric readings were carried out at 700 nm, and results were expressed as mg GA/g F.W. Total flavonoids were determined according to the method described by Lombard et al. (2002), with minor modifications. Processed material (500 mg) was extracted three times with a solution (2 ml) containing 95% ethanol and 10% acetic acid (85:15). After agitation for 20 min, samples were centrifuged at 6500 rpm for 15 min. Antioxidant content in guava and araçá 385 The supernatants were collected, and the final volume was adjusted to 10 ml with the same solution. Total flavonoids were determined on plant extract (500ml), followed by the addition of 5% AlCl3 (500ml) and extract- ing solution (2 ml). After a 30 min rest, sample absor- bance was determined by spectrophotometry at 425 nm. A calibration curve was built with rutin, and the results are expressed as mg of rutin/100 g F.W. Antioxidant activity was determined according to the method proposed by Mensor et al. (2001), with minor modifications. Samples were treated with the same extraction solution used for total phenolic deter- mination, using ethanol and acetone. A standard solution containing 100mM diphenylpicryl-hydrazyl (DPPH) was prepared, with which two calibration curves were built as follows: (1) DPPH reference curve: different amounts of DPPH, in the range 10–300 nmol, coming from the standard DPPH solution, were prepared in six test tubes. Volumes were adjusted to 3 ml with 96% ethanol. After incubation for 40 min in the dark, the absor- bance was measured at 517 nm, against a control consisting of 96% ethanol. (2) AA reference curve: in five test tubes, AA was added in the concentration range 6.25–37.5mg/ml, from a 250mg/ml standard solution. Volumes were adjusted to 0.15 ml with 96% ethanol, and then the DPPH standard solution (2.85 ml) was added. After 40 min in the dark, readings were carried out at 517 nm, against a control constituted of 96% ethanol. Antioxidant activity was determined on plant extracts (0.15 ml), following the addition of the DPPH standard solution (2.85 ml). Results were expressed as mmol of reduced DPPH/g F.W. and AA equivalent (mg AAE/g F.W.). Table 1. Origin of guava (G) and araçá (A) accessions from the AGB of Embrapa Semiárido used for antioxi- dant activity determination Access Origin State G01MA Caxias MA G02MA Caxias MA G03MA Coelho Neto MA G05MA Buriti MA G07MA Mata Roma MA A08MA Mata Roma MA G10MA Presidente Vargas MA G11MA Presidente Vargas MA G12MA Cajari MA G13MA Viana MA G14MA Pindarı́ MA G15MA Bom Jardim MA G16MA Bom Jardim MA G17MA Santa Luzia MA G18MA Santa Luzia MA G19MA Graiaú MA G20MA Tuntum MA G21MA Tuntum MA G22MA Presidente Dutra MA G23MA Presidente Dutra MA G24MA Colinas MA G25MA Colinas MA G26MA Paraibano MA G28PI Colônia do Gurgueia PI A29PI Eliseu Martins PI G30PI Canto do Buriti PI G31PI Brejo do Piauı́ PI G32PE Ibimirim PE G33PE Ibimirim PE G34PE Ibimirim PE G35PE Ibimirim PE G38PE Pesqueira PE A42PE Escada PE A43PE Escada PE A44PE Escada PE A45PE Escada PE G46PE Escada PE G47PE Riacho das Almas PE G48SE Nossa Senhora da Glória SE G49SE Dores SE G50SE Capela SE G51SE Capela SE G52SE Capela SE G53SE Japoratuba SE G54SE Japoratuba SE G55SE Pirambu SE G58SE Santa Luzia SE G59SE Umbamba SE G60SE Umbamba SE G61SE Riachão dos Dantas SE G64BA Antonio Gonçalos BA G65RO Ji-paraná RO G66RO Ouro Preto do Oeste RO G67RO Jaru RO G68RO Buritis RO G69RO Buritis RO G70RO Buritis RO G73RO Ariquemes RO A78RO Candeias do Jamarı́ RO Table 1. Continued Access Origin State A79RO Porto Velho RO A80RO Porto Velho RO G81RO Porto Velho RO G83AM Itacoatiara AM G87AM Iranduba AM G92AM Manacapuru AM G94AM Autazes AM G95AM Autazes AM G96AM Autazes AM G98AM Autazes AM A100AM Careiro AM MA, Maranhão; PI, Piauı́; PE, Pernambuco; SE, Sergipe; BA, Bahia; RO, Rondônia; AM, Amazonas. L. C. Corrêa et al.386 Statistical analyses Results were subjected to analysis of variance, and averages were compared by the Scott–Knott test at 5% probability using the SAS package (SAS Institute Inc., 2002). Data were also analyzed by the linear Pearson correlation. Results Free AA concentration was determined in guava and araçá samples reported in Table 1. A variation from 44.66 to 409.77 mg/100 g was observed in guava accessions, and the highest con- centration was detected in G03MA, G47PE and G38PE (Supplementary Table S1, available online only at http://journals.cambridge.org). In araçá accessions, the variation was from 20.23 to 67.80 mg/100 g. In these fruits, the highest concentration was found in A100AM, A78RO and A42PE (Supplementary Table S1, available online only at http://journals.cambridge.org). Lycopene and b-carotene The highest lycopene concentration was found in guava (4.04 mg/100 g) in the accession G73RO, characterized by a dark pink-coloured pulp, followed by G20MA (pale pink) and G32PE (pale pink) accessions. On the other hand, the lowest value (0.04 mg/100 g) was observed in the white-coloured G96AM accession (Table 2 and Supplementary Table S1, available online only at http://journals.cambridge.org). In araçá acces- sions, in fruits whose pulp colour varied from cream to yellow (Table 2), the variation was from 0.03 to 0.45 mg/100 g in A78RO and A100AM accessions, respec- tively (Supplementary Table S1, available online only at http://journals.cambridge.org). The b-carotene concentration ranged from 0.13 to 2.54 mg/100 g in guava accessions, and fruits presenting Table 2. Pulp colour of guava (G) and araçá (A) from the AGB of Embrapa Semiárido Access Pulp colour G01MA PO G02MA DO G03MA DO G05MA PO G07MA PO A08MA RD G10MA DP G11MA PP G12MA PP G13MA DO G14MA PO G15MA PO G16MA PO G17MA PP G18MA PO G19MA PO G20MA PP G21MA DO G22MA DO G23MA DP G24MA DP G25MA PP G26MA PP G28PI RD A29PI PO G30PI PP G31PI DO G32PE PP G33PE PP G34PE WH G35PE PP G38PE DP A42PE RD A43PE RD A44PE RD A45PE CR G46PE RD G47PE PO G48SE PO G49SE DO G50SE PO G51SE CR G52SE DO G53SE PO G54SE DO G55SE PO G58SE DP G59SE DP G60SE CR G61SE PP G64BA PP G65RO DP G66RO PP G67RO DP G68RO WH G69RO DP G70RO DP G73RO DP A78RO PO A79RO RD A80RO CR Table 2. Continued Access Pulp colour G81RO CR G83AM DP G87AM RD G92AM DP G94AM PO G95AM WH G96AM WH G98AM PP A100AM CR PO, pale orange; DO, dark orange; RD, red; PP, pale pink; DP, dark pink; WH, white; CR, cream. Antioxidant content in guava and araçá 387 a higher concentration had a pulp colour from orange to pink (Table 2 and Supplementary Table S1, available online only at http://journals.cambridge.org). It can be noticed that guava accessions characterized by white- or cream-coloured pulp presented a very low carotenoid concentration. In araçá accessions, the b-carotene con- centration varied from 0.18 to 0.73 mg/100 g in A45PE and A08MA accessions, respectively. Total phenolics The attention has been focused on another class of anti- oxidants, and phenolic compounds were considered. Total phenolics, expressed as equivalent of GA (GAE), varied from 158 to 447 mg GAE/100 g in guava tree accessions, and the concentration was highest in G03MA, G10MA and G01MA (Supplementary Table S1, available online only at http://journals.cambridge.org), characterized by a dark orange, dark pink and pale orange fruit colour, respectively (Table 2). In araçá accessions, phenolic compound concentration between 231 and 338 mg GAE/100 g was found. The highest concentrations were present in A100AM, A43PE and A80RO accessions. Total flavonoids We proceeded with the determination of the most common group of phenolic compounds, that are flavo- noids, according to the procedure described in the Method section. Total flavonoids, expressed as rutin concentration, varied from 10.67 to 46.82 mg/100 g and from 19.64 to 36.33 mg/100 g in guava and araçá accessions, respect- ively. The highest concentration was found in guava G21MA, which presented a dark orange-coloured pulp, in G24MA (dark pink) and in G55SE (pale orange) (Table 2). In araçá, the highest concentration was found in A43PE, A29PI and A08MA (Supplementary Table S1, available online only at http://journals.cambridge.org). Antioxidant activity Antioxidant activity of guava and araçá fruit extracts was determined as reported in Methods. A variation from 280 to 812 mg/100 g in antioxidant activity, expressed as AAE, among the guava accessions was determined, while in araçá accessions, the variation was from 398 to 575 mg AAE/100 g (Supplementary Table S1, available online only at http://journals. cambridge.org). If antioxidant activity is expressed as mmoles of reduced DPPH/g of sample, it was observed that the values were from 23.87 to 70.42mmoles/g in guava and from 33.21 to 47.38mmoles/g in araçá (Supplementary Table S1, available online only at http://journals.cambridge.org). The Pearson correlation study (Table 3) showed a high positive correlation between phenolic compound concentration and antioxidant activity and between b-carotene and flavonoid concentration. The correlation was moderate among other data, except for lycopene, which presented a non-significant correlation with anti- oxidant activity, phenolic compounds, free AA and flavonoids. The behaviour presented by b-carotene was similar to that shown by phenolic compounds (Table 3). Discussion It was suggested that the daily intake of vitamin C for an adult should be around 60 mg/day (Sauberlich, 1990). However, a revision reporting epidemic studies on antioxidant effects suggested that a daily dose of 150 mg vitamin C, preferably in association with other vitamins, may be related to a lower incidence of cardi- ovascular diseases and cancer (Diplock et al., 1998). Accessions studied could be a good source of vitamin C, and the ingestion of 40 g of fruits coming from, for instance, G03MA accession could supply the daily need for vitamin C. Luximon-Ramma et al. (2003) suggested a daily ingestion of about 100 g of white guava, since they found a vitamin C concentration of around 150 mg/100 g. In spite of the lower free AA concentration in comparison with guava, araçá fruits present a sufficient vitamin C content to supply, at least in good part, the human daily need. Free AA concentration found in some accessions was higher than that showed in similar studies. Yan et al. (2006) found about 144 mg/100 g in the ‘Kampuchea’ guava fruit cultivar, with peel, while Thaipong et al. (2006) reported a variation from 174 to 397 mg/100 g in four different guava genotypes. On the other hand, Table 3. Pearson correlation indexes of antioxidant activity (AOX), total phenols (PHEN), free AA (FAA), total flavonoids (FLV), lycopene (LYC) and b-carotene (BCT) AOX PHEN FAA FLV LYC PHEN 0.95** FAA 0.57* 0.52* FLV 0.53* 0.40* 0.36* LYC 20.02 20.09 0.29 0.27 BCT 0.32* 0.18 0.41* 0.81** 0.46* *,**Significant at 1 and 5% probability, respectively, according to t test. L. C. Corrêa et al.388 Wille et al. (2004) found about 61 mg/100 g in araça pear–guava (Psidium angulatum), native of Amazonas state, similar to the results showed in the present paper. Considering lycopene and b-carotene as a set, our results are close to those reported by Setiawan et al. (2001), who detected a total carotenoid concentration between 0.89 and 4.6 mg/100 g in guava fruits. On the other hand, higher concentrations were found by Mendonça et al. (2007), and lycopene and b-carotene were found to be the most widely distributed caro- tenoids in guava. Analyzing total carotenoids in the white pulp ‘Cordibel 4’ and in the red pulp ‘Cordibel 1’ cultivars, authors found a variation from 0.28 to 0.75 mg/100 g and from 1.34 to 8.74 mg/100 g, respect- ively. Thaipong et al. (2006) did not detect any caroten- oid content in a white pulp cultivar, while a variation from 0.78 to 2.93 mg/100 g was observed in three pink pulp guava cultivars. Padula and Rodriguez- Amaya (1986) studied IAC-4 guava, and observed that lycopene was the most abundant carotenoid as well as the most represented in accessions of guava fruits considered in the present study. Lycopene is reported to be found in tomatoes, water melon, pink guava, pink grapefruit and papaya, with tomatoes and tomato-based foods accounting for more than 85% of all the dietary sources of this carotenoid (Rao and Rao, 2007). According to these authors, a typical raw tomato fruit presents a lycopene concen- tration from 8.8 to 42.0mg/g F.W., while in a typical pink guava fruit, it can be found at 54.0mg/g. The value found in the present study for G73RO was 40.4mg/g F.W, while Chandrika et al. (2009) reported a value of 45.3 ^ 8.0mg/g F.W. in the ‘Horana red’ from Sri Lanka, which is very close to the value found in the G73RO accession of the present study. These results confirmed that guava fruits could be an additional excellent source of lycopene. It is also expected that red araçá cultivars, which are preferred by local consumers, should have higher lycopene concentration. Studies show that lycopene-supplemented diets may effectively counteract the risk of many chronic diseases, such as cancer and heart diseases (Giovannucci, 1999). Lycopene, as well as other carotenoids, can act as a free radical scavenger, and some accessions could be recommended as a source of this substance, which would be a proposal for future studies. As regards total phenolics, the values showed in the present paper are similar to those found by Thaipong et al. (2006), who described a variation from 170 to 340 mg/100 g on the same fruits. Patthamakanokporn et al. (2008) and Alothman et al. (2009) reported values from 148 to 185 mg/100 g GAE in studies carried out in Thailand and Malaysia, respectively. It was noticed that the highest values of antioxidant activity were found in fruits with a high phenolic compound concentration (Supplementary Table S1, available online only at http://journals.cambridge.org), confirming the results reported by Luximon-Ramma et al. (2003) that fruits characterized by a low phenolic compound concentration expressed a low antioxidant activity. These compounds certainly contribute to the increase of fruit antioxidant potential, bestowing to these substances the good free radical scavenger prop- erty, which has already been pointed out by Chen and Yen (2007), as the main responsible factor for the high antioxidant activity in guavas. Free radicals, or more precisely their excessive production, can promote many human disorders, such as cardiovascular diseases, diabetes and cancer, contributing to the increase of mortality risk in human beings (Luximon-Ramma et al., 2003). The consumption of foods containing substances capable of removing these radicals (active oxygen species and active nitrogen species) can contribute to the improvement of human health. Although flavonoids show positive correlation with antioxidant activity, they do not collaborate significantly to the increase in fruit antioxidant activity, due to their low concentration in guava and araçá. Luximon-Ramma et al. (2003) reported similar results in some fruits, including white and red guava. Another factor to be considered is that the antioxidant capacity of flavo- noids can suffer from the influence of oxygen in the atmosphere, because their easy auto-oxidation, mostly catalyzed by transition metals, produces superoxide radical, which can reduce the total antioxidant capacity of flavonoids (Chen and Yen, 2007). Alothman et al. (2009) and El Sohafy et al. (2009) reported a flavonoid concentration of 24.05 and 39.5 mg/100 g in guava, expressed as quercetin, similar to values found in the present paper, however, expressed as rutin. Antioxidant activity of fruits considered in the present work, expressed as AA equivalent, was very high, when compared to that found by Yan et al. (2006), who reported 218 and 310 mg AAE/100 g in green and ripe guava fruits, respectively. When the antioxidant activity is expressed as trolox equivalent, a variation from 16 to 32mmoles/g was reported in four guava cultivars (Thaipong et al., 2006), while Luximon-Ramma et al. (2003) reported an antioxidant activity of 7 and 17mmoles/g, always as trolox equivalent, in pink and white pulp guava, respectively, and of 45mmoles/g in yellow pulp Psidium cattleianum. The results of Pearson correlation study (Table 3) differ from those reported by Thaipong et al. (2006), who mentioned a high negative correlation between b-carotene and phenolic compounds, but the Antioxidant content in guava and araçá 389 correlation was positive between free AA and phenolic compounds. The authors also reported a high positive correlation of antioxidant activity with phenolic com- pounds and free AA, similar to that reported in the present study. The correlation between free AA and antioxidant activity was moderate, due to the presence, in araçá and in some guavas, of a very low con- centration of free AA, when compared to those which presented the highest concentration. This confirmed the results by Luximon-Ramma et al. (2003), who reported a low correlation between these two data (0.07), relating the fact to the low concentration of free AA found in their study. On the other hand, the low correlation between antioxidant activity and caro- tenoids, b-carotene and lycopene content, reported in the present paper, was probably due to the analytical method used, since both solvents used for extraction and DPPH preferably react with hydrophobic com- pounds. The present paper is one of the widest studies involving antioxidant compounds in guava and araçá accessions carried out in Brazil. In addition to confirm the high concentration of antioxidants in guava, it has been revealed that araçá fruits represent an important source of these substances, especially phenolic com- pounds. This characteristic, along with their good consumer acceptance, should be taken into account in order to offer a wider visibility to this Brazilian native species. Regarding guava fruits, the high free AA content found in some accessions, well above that found in most of studies reported in literature, should be mentioned. Furthermore, some of these accessions presented a high phenolic compound concentration, in particular in acces- sions from Maranhão state, in which five accessions (G01MA, G02MA, G03MA, G10MA, G16MA, G17MA and G22MA) showed the highest concentration of both these two groups of antioxidants, increasing significantly the antioxidant activity of the fruits. A great variation was found within the analyzed para- meters, showing a great potential for breeding, for guava accessions as well as for cultivation options, given the easy adaptation of the genus, good consumer acceptance and market opportunities, which can be allied to the health properties of fruit functional compounds. A strong positive correlation was found between anti- oxidant activity and phenolic compounds, both in guava and in araçá, which classified them as important contributors to the antioxidant activity of these fruits. 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