Peach Palm (Bactris gasipaes Kunth.): Ancestral Tropical Staple with Future Potential

A pre-Columbian staple, Bactris gasipaes Kunth. is a palm tree domesticated around 4000 years ago, so appreciated that a Spanish chronicler wrote in 1545, “only their wives and children were held in higher regard” by the Mesoamerican natives. The peach palm is an integral part of the foodways and gastronomy of Ecuador, Colombia, Bolivia, Peru, Brazil, and other tropical American countries; meanwhile, it is almost unknown in the rest of the world, except for hearts of palm. Although abundant, the species faces anthropogenic threats. The purpose of this study is to describe and summarize the physicochemical, nutritional, and bioactive characteristics of the peach palm and its two main alimentary products: hearts of palm and fruits, highlighting the functional and antioxidant potential of the latter, showing both ancestral and modern uses. There is active research on peach palm products and coproducts that aim for better, more sustainable uses of its traditional and recently found properties. The review and presentation of studies on this strategically relevant species can motivate the protection of endangered populations and stimulate new lines of research to advance development in the food, pharmaceutical, and cosmetic industries, with fair trade, sustainable development goals, and adaptation to climate change in mind.


Introduction
The Amazon is a multicultural and multiethnic space where natural resources have been used ancestrally to provide housing, medicine, and food to its inhabitants [1]. Some of these are fruits that are currently considered promising for their sensory, nutritional, and ethnomedicinal characteristics [2][3][4]. Among these important species, palms are an important family. Palm trees are considered to be more useful to mankind than any other family, inspiring the tree of life motif [5]. An important palm in the Amazon and tropical America is Bactris gasipaes Kunth., in the Areacaceae family, the most important pre-Columbian American palm [6], a polyvalent pre-Columbian staple. This species, among many others, is expected to undergo changes in the land area suitable for cultivation due to climate change, with loss of current cultivation areas and the emergence of new ones [7]. This would not be the first climate event in Amazonia [8], and B. gasipaes overcame earlier events.
There is abundant research published on B. gasipaes, including excellent review articles [9,10]. We found the need for an integrated, updated view that presents the current knowledge of the food and phytochemical study of the species. Most research on the species centers on its biology and agriculture.  [19]. Shaded areas, main complexes: red: Occidental; green: Maracaibo; brown: Upper Amazonia; yellow: Eastern Amazonia. Source: [20].

Morphological Description
The species is characterized by being cespitose, i.e., several trunks (one to fifteen) with heights from six to twenty meters stemming from the point of origin, smooth in appearance, with evident internodes, surrounded by a ring of black thorns ( Figure 2A) [16,20]. The leaves, located at the top of the trunk, are arched and long (up to 100 cm), their sheath covered with small white or dark brown spines; inflorescences appear in intrafoliar clusters and are monoecious: female and male flowers emerge from the same stem; with some structures, such as the peduncle, covered with spines. The species can produce up to ten inflorescences per year [17,21].
Inside the trunk, the heart of palm can be found, a vegetable considered a delicacy: cylindrical and sweet-tasting, it consists of the apical meristem, divided into basal, central and apical with marked differences in texture due to the arrangement of the structural fibers; its harvest results in the death of some species [22,23], but not in Bactris spp., and other cespitose palms. This is why it has become a more sustainable prime source for hearts of palm, together with Euterpe oleracea (Açai).
The fruits are spherical or ovoid in shape, and come in a variety of sizes; the largest are up to10 cm long and up to 6 cm in diameter, they are clustered, green when unripe, and from yellow to orange when ripe [5,24]. The inside of the pulp is floury or oily depending on the variety, and in the center, there is a seed that resembles a very oily small coconut ( Figure 2B). According to the weight of the fruit, B. gasipaes is categorized as microcarpa (<20 g), mesocarpa (>21 g, <70 g) and macrocarpa (>70 g) ( Figure 2C), and also as orange, yellow, and lately, white varieties [25,26]. The fruit presents low polyphenol oxidase activity, which makes it suitable for minimally processed products [18]. and from yellow to orange when ripe [5,24]. The inside of the pulp is floury or oily de-pending on the variety, and in the center, there is a seed that resembles a very oily small coconut ( Figure 2B). According to the weight of the fruit, B. gasipaes is categorized as 4acrocarpa (<20 g), mesocarpa (>21 g, <70 g) and macrocarpa (>70 g) ( Figure 2C), and also as orange, yellow, and lately, white varieties [25,26]. The fruit presents low polyphenol oxidase activity, which makes it suitable for minimally processed products [18]. The similarity with other species suggests the species was domesticated in areas of the Amazon through hybridization [5,27,28]. Its food use is mainly for its oil content, plus the harvesting process has ethnic, cultural, and traditional value [5,15,28,29]; in addition, it is attractive as a promising industrial resource for new products derived from the same species (chonta, palm heart, wood) [30,31].

Mythical Origins
There are several related origin myths for B. gasipaes in the traditions of Peruvian (Asháninka), Colombian (Yukuna Matapi), and Ecuadorian (Shuar Achuar) native peoples [32][33][34][35]. A common motif is that chonta and maize come from the otherworld, stolen The similarity with other species suggests the species was domesticated in areas of the Amazon through hybridization [5,27,28]. Its food use is mainly for its oil content, plus the harvesting process has ethnic, cultural, and traditional value [5,15,28,29]; in addition, it is attractive as a promising industrial resource for new products derived from the same species (chonta, palm heart, wood) [30,31].

Mythical Origins
There are several related origin myths for B. gasipaes in the traditions of Peruvian (Asháninka), Colombian (Yukuna Matapi), and Ecuadorian (Shuar Achuar) native peoples [32][33][34][35]. A common motif is that chonta and maize come from the otherworld, stolen by human or demigod visitors. In a Catío myth, the immortals of Armucurá, a planet below earth, feed on the vapors of B. gasipaes, but it is the human visitors that return with seeds for human cultivation and consumption [35]. In these stories, practical elements are transmitted: the quality of the wood for the making of proper weapons; the food value of the species; and the importance of not throwing the seeds away but saving them for cultivation. The interdependence of the cultivated palm and humans is shown in these stories, pointing to a domesticated species, no longer able to survive in the wild. Another example of how ingrained B. gasipaes is in the local cultures is the calendar use: "Pupunha summer" is part of the calendar of the indigenous peoples of the Tiquié river in Brazil [36], and the harvest season between December and March is an important event. Today, chonta festivities that reenact these myths survive and are becoming a community tourism product [37].

History
The origin of the species is unclear, but consensus points to the Bolivian amazon as a possible origin [5]. Three hypotheses coexist: a southwestern Amazon domestication, a northwestern South America domestication, and that of multiple origins. Two dispersals are supported by genetic diversity patterns: one along the Ucayali river, northwestern South America, and into Central America with a starchy, fermentable fruit used as a staple; another, along the Madeira river into central and eastern Amazonia in which the smaller, starchy, and oily fruit is used for snacking [15]. Similarity with other species suggests the species was domesticated in areas of the Amazon through hybridization, with highest genetical diversity in northern Peruvian and Ecuadorian Amazon. The domestication of the species is tentatively dated between 4000 and 3000 years BP, coincident with the establishment of sedentary communities in Amazonia [5,27,28]. The earliest archaeological remains of the species, presumably already cultivated, are dated 2300-1700 BC in Costa Rica [38].
The records about the species date back to the fifteenth century, and it is presumed that the beginning of its production under the Spanish was as timber, not as a food resource. During the Spanish conquest, native crops such as B. gasipaes lost importance, due to the massive native population loss [8] and the adoption of European productive systems. The European contact in the fifteenth-sixteenth centuries in Central America is marked by the awe of the Spaniards towards how appreciated the species was. Spanish chronicler Godínez Osorio wrote in 1575 that, "only their wives and children were held in higher regard" [39]. The timber of B. gasipaes was used in the early 1540s by the Spaniards to build fortifications because of its hardness and the fact that the trunk is naturally covered by thorns. It was also used as a weapon: more than 30,000 palms were cut down to submit the natives to hunger [40]. The same chronicle attests to the consumption of hearts of palm by a Chichimeca army under the orders of the Spaniards. Before the Spanish invasion, the fruit of B. gasipaes was a staple, and the harvest was one of the most important events of the year, with most births taking place nine months after it. Even today, 500 years later, the use of the species has not reached back to its pre-Hispanic level [15,17,41]. B. gasipaes fruit has been relegated pejoratively as a "fruit of the Indians", a forgotten, neglected fruit [39,42]; however, in times of scarcity it has been used to provide food security [43], and it still is today [9].

Traditional Uses
The main use of this species is timber. It is suggested that domestication of the species was primarily because of its wood [32]. The species is also an important part of the Amazonian and Central American foodways and ethnopharmacology, and material and social uses are also listed [44]. The main morphological structure from an ethnopharmacological perspective is the root, used to reduce inflammation and infections, and both to promote female fertility and act as an aid during pregnancy [20].
From the alimentary perspective, the main products are hearts of palm and fruits. The palm heart, already documented in the sixteenth century, is today one of the most important non-timber products in South America [45], and probably the best-known part of B. gasipaes worldwide, used in the preparation of salads, pizza, and even ceviche [46]. B. gasipaes hearts of palm are replacing those of other species, often endangered by overharvesting, mainly Euterpe spp. Being a cespitose species, the plant is not killed by prudent harvesting and thus a more sustainable product can be obtained. Canned hearts of palm are currently exported by several American countries. Ecuador and Bolivia are the largest exporters [47].
The fruit, despite not being produced in the same proportion, is a popular traditional food that needs to be processed prior to consumption, due to its high oxalate and other antinutrient content [48]: cooked fruit, flour, fermented chicha, slowly fermented silage [38], and oil are among the traditional uses. The fruit and its processing byproducts have also been used as animal and fish feed [5,[49][50][51]. Larger fruit is less palatable than smaller fruit, due to a coarse, dry texture. To compensate, the fruit is frequently consumed with mayonnaise or sour cream.
An indirect alimentary use of the species is the use of the decomposing trunk after felling the palm to raise chontacuros, the larvae of Rhynchophorus palmarum L., a " . . . delicious, butter-tasting" delicacy [52] in the Ecuadorian and Peruvian Amazonia rich in protein, vitamin E, and minerals, also used against cough, asthma, and other respiratory affections [53][54][55].
Some Indigenous communities, such as the Colombian Uitoto, do not have access to table salt, so they make "bush salt," obtained from burning, dissolving, filtering, and drying plant material, including the barkless stem of B. gasipaes. This process yields a mixture of salts: chloride, sulfate, and carbonate are the main anions, and potassium is the main cation. These salts are not particularly good tasting because of the high carbonate and low sodium content: their taste was described by Spanish chronicler Juan de Castellanos in the sixteenth century as "almost having the taste of sardines and herrings." There is also a cosmic, alchemical, significance for communities, where extracting salt is considered to be the cleansing of the evil and disease and converting them into human food [56].
In other uses, the wood is used in the manufacture of flooring, marimbas, bows and arrows, spears, knives, and building material, the thorns are used as needles, the leaves for roofing, the fruit is used together with Clibadium surinamense L. leaves to make fish poison [53]. Table 2 summarizes traditional ethnomedical, alimentary, and other uses of B. gasipaes. The use of the wood is so present that the verb achuntar (to hit the mark) has entered the Spanish language from chunta, the quechua name for B. gasipaes, referring to the use of the wood to make arrows [57]. Table 2. Traditional uses of B. gasipaes ordered by plant organs.

Plant Organ
Applications Ref.

Modern Uses
Aside from the traditional uses, new applications are being found for B. gasipaes. Chonta pulp, in combination with other materials, is being implemented in the decontamination of water of minerals such as lead and cadmium [29,60]. Sensory evaluation and consumer acceptance analysis has been performed: oily fruit is more attractive and less averse than starchy fruit [61]. This may influence genetic development of the species and also guide the manufacture of food products from the fruit. Food products are being produced and marketed other than hearts of palm: jam, jelly, wine, flour and flour products (bread, pudding, pasta, etc.) [62,63].
There is a variety of alimentary and industrial applications and new uses for B. gasipaes, both as product and from the industry byproducts: functional food ingredients, brewing, dyes, and others. Some examples are listed in Table 3.

Nutritional Composition
The fruit of the peach palm, macrocarpa variety, is a starchy, ancestral staple, while meso and microcarpa varieties are used as snacks due to their smaller size, and to obtain oil. In order to consume the fruit, it is necessary to ferment or cook it for 1-3 h, usually in salt water, to remove the irritating oxalate crystals usually found in red drupes and reduce other antinutrients, such as phytates and tannins [20,71,72]. The nutritional composition of the fruit is summarized in Table 4 and that of the flour in Table 5.
The fruit of B. gasipaes is characterized by the amount of carbohydrates and fats contained that tend to increase when cooked. The oil obtained from the mesocarp is rich in unsaturated fatty acids, particularly oleic acid, while saturated fatty acids such as lauric acid are found in the seed [73,74]. The fruit is also high in dietary fiber, and although the protein content is low, all essential amino acids are present. Essential minerals are also present: K (12%), Se (9%), and Cr (9%) are the most abundant [5,24]. In addition, the bromatological characterization of the epicarp or peel shows: protein, 2.3%; ash, 2.3%; raw fiber, 8.2%; detergent acid fiber, 13.4%; and detergent neutral fiber, 63.6%. This composition supports the use as raw material for the production of flour [75,76].
The industrialization of products derived from this fruit has been increasing in recent years. The production of flour obtained from the mesocarp of the fruit, in combination with other flours such as wheat, corn, or quinoa and technological adjuvants, are acceptable by consumers and can be used in different matrices (sandwiches, cakes, pasta), the high carotenoid content makes the flour a potentially functional ingredient [66,77,78]. Nutritional composition of fruit from different origins is summarized in Table 4. There is variability in the nutritional values that can be explained by the different B. gasipaes varieties, size, and starch-oil composition of the fruit. The nutritional parameters of flours from different origins are shown in Table 5. Flour from macrocarpa and seedless varieties show higher carbohydrate content. Additionally, flour from seedless fruits has a higher protein content. The oil obtained from B. gasipaes is rich in mono and polyunsaturated fatty acids, particularly oleic, with the presence of ω-3 and ω-6 acids and bioactive lipids. It can be considered a heart-healthy oil [82,83].

Biological Activity
The information derived from research on the biological activity of the fruit of B. gasipaes (pulp, seed, peel, or whole fruit) has been summarized in Table 6-antioxidant  activity, and Table 7-other biological activity. Most studies focus on antioxidant and protective activity, due to the presence of carotenoids. There are other studies on its biological activity that are not related to its traditional use. Within these activities we can mention the hypoglycemic capacity, modulation of lipid metabolism, cytotoxic activity, and its effect on sperm motility [84].
Today there is an interest in the food industry in replacing synthetic dyes such as tartrazine (yellow-orange color) as additives due to adverse reactions related to hypersensitization to salicylic acid, complications in respiratory diseases, and long-term genotoxic effects [93] of dyes such as β-carotenes, although they are not as stable in extreme conditions [94,95]. However, carotenes have an added value due to the great diversity of biological activities they present, mainly as antioxidants. From the raw and cooked pulp, α-carotene, E-γ-carotene, and E-lycopene have been identified using high-resolution liquid phase chromatography with a diode network detector and visible ultraviolet spectroscopy (HPLC-DAD-UV/Vis) [86], and HPLC with a photodiode-array detector (PDA) coupled to mass spectrometry with an ion trap analyzer (MS) and ultraviolet spectroscopy (UV/Vis). The concentration of these components varies according to the place of origin of the sample, where the ones originating in Bolivia are those that presented higher concentrations [96,97], while Santos [98] have reported the identification of lutein (11.9 mg/Kg) and cis lutein (2.22 mg/Kg) using HPLC-PDA-UV/Vis.
A comparison of carotenoid extraction from pulp, between supercritical fluids, traditional methods of methanolic extraction, and the Soxhlet extraction method using petroleum ether was performed [99]. The highest extract yield was that obtained by Soxhlet extraction, followed by methanolic extraction, and finally supercritical fluids with extraction conditions of 300 bar and −60 • C. The concentration of carotenoids (mg/g of extraction) differs from the yield, with the order of highest to lowest extraction: Soxhlet, supercritical fluids, and methanolic extraction. However, the antioxidant activity evaluated by spectroscopic techniques compared to caffeic acid and quercetin show that the best antioxidant activity is that of the extract using the Soxhlet extraction, then methanolic extraction, and finally supercritical fluids, most likely the type of carotenoids obtained differs with the type of extraction.
Another promising method is ultrasound-assisted extraction, in this case to obtain total carotenoids from the peel of the chonta fruit and optimize extraction conditions: ultrasonic intensity (1528 W/m 2 ), temperature (35 • C), and time (30 min), obtained 163.47 mg carotenoids per 100 g fruit [100], which is considered a significant amount of carotenoids.

Sustainable Development Goals (SDG)
B. gasipaes cultivation and uses are linked to several SDGs through food and nonfood initiatives. Examples include farming, products recovered from waste, and food safety are shown in Table 9. The main SDGs are Responsible Consumption and Production (nine publications), Life on Land (five), and Climate action (three).

Sustainable Development Goals (SDG)
B. gasipaes cultivation and uses are linked to several SDGs through food and non-food initiatives. Examples include farming, products recovered from waste, and food safety are shown in Table 9. The main SDGs are Responsible Consumption and Production (nine publications), Life on Land (five), and Climate action (three).

Major Concerns
Even though the species is widely spread, there is concern for the loss of populations due to soybean cultivation, forest clearance, and road building [109], as well as genetic erosion due to centuries of neglect [38]. Lately the forest fires due to anthropogenic action and climate change have risen as a concern. The modification of current cultivation areas, with an allover descent in surface due to the climate crisis [7] is also a major concern.

Conclusions
The peach palm is a very important species in tropical America, especially as a food source that not only provides food safety but also several opportunities for sustainable industrial production. The fruit is a rich source of bioactive compounds with significant antioxidant capacity, and nutritional, both macro and micronutrient, and functional properties.
Prudent cultivation and use of B. gasipaes in a way respectful of traditional methods, coupled with sustainable innovation has potential for advancing the SDGs.
Despite its widespread cultivation area, populations, and genetic diversity of the species, they are at risk due to deforestation, neglect, and the climate crisis.