Keywords

1 Taxonomic Characteristics

Caryocar (souari trees) is a genus of flowering plants, in the family Caryocaraceae described formerly as a genus by Linnaeus, in 1771. Besides C. coriaceum, there are other species of the genus Caryocar in Brazil: C. brasiliense, C. villosum, C. cuneatum and C. glabrum. (Lorenzi and Matos 2008).

Trees of the genus Caryocar yield a strong timber. Some of the species have edible fruits, called souari-nuts or sawarri-nuts.

Caryocar coriaceum Wittm., is an endemic species to Brazil, with cultural, alimentary and ethnopharmacological values (term used here to describe medical practices). It is used in traditional medicine systems (see Elisabetzky 2003).

In 2006, Caryocar coriaceum was included in the IUCN Red List of Threatened species.

2 Major Chemical Constituents and Bioactive Compounds

Pequi content of the pulp is rich in nutritional compounds, such as fatty acids, carbohydrates, proteins, carotenoids, vitamin E, and retinol. The fruit pulp also has high levels of pectin and tannins, and polyunsaturated oils. In the fixed oil of C. coriaceum, were identified saturated and unsaturated fatty acids, with the major component fatty unsaturated oleic acid. Featuring even in the composition fatty polyunsaturated linoleic acid (Figueiredo 2012).

Regarding the nutritional value for the species C. coriaceum Wittm., the study of Oliveira et al. (2010) showed a protein content of 2.09% and 23.19% of lipids. Pequi’s pulp is also rich in vitamin A and minerals, especially P, Ca, Cu and Fe (Araújo 1995).

Edible portions of fruit oil are: the pulp and the almond, for its characteristic taste and smell, as well as being a source of lipids and antioxidant vitamins (A and E), they are well used as food in regional food, replacing other sources of fat, such as grease or bacon. Phytochemical analysis of the essential oil obtained from almonds was composed almost exclusively of ethyl hexanoate (Lorenzi and Matos 2008).

Due to the affordable price, pequi is a valuable food source for the low-income population in the region (Figueiredo et al. 1989; Braga 1960; Silva and Medeiros Filho 2006).

Although the fruit is rich in nutrients and has a variety of uses, especially the species C. coriaceum, pequi has received inadequate attention in national and international research. There are only a few studies in the special literature that would involve biometry and the chemical and nutritional characterization of fruits of this species (Oliveira et al. 2010; Silva and Medeiros Filho 2006; Oliveira 2009).

As highlighted by Figueiredo (2012), little has been done to preserve the existing germplasm of this species and study its possible domestication with the aim of sustainable utilization.

Pequi has many uses, such as being used to produce oil with high versatility in regional food for sauces and dressings preparation, in cosmetic industry for producing soaps and creams, as well as being used for fuel production and lubricants (Oliveira et al. 2008; Pianovski et al. 2008).

3 Morphological Description

C. coriaceum, popularly known by pequizeiro, pequi, piqui and pequá, is a leafy and branchy tree with trunk coated with dark, thick and furrowed skin and opposite leaves, ternate, oval leaflets, glabrous (hairless), green-glistening, rich in tannin, providing dye substance; more or less leathery. The flowers are large, yellow with red stamens, gathered in terminal bunches (Braga 1960; Figueiredo 2012).

“Pequizeiro” tree reaches an average of 6–8 m high, and its inflorescences produce a varied number of large (5.0–7.5 cm in diameter) and colored from green to white and twilight anthesis flowers (hermaphrodite and actinomorphic) (Araújo 1995).

Studies of C. brasiliense and C. villosum, indicate that the species of this genus are heavily cross-pollinated, and small nectar bats (socicina geoffroyi and Anoura Glossophaga) are the main pollinators, and the Protandry and herkogamy (spatial separation of anthers and stigmas) work as key mechanisms against autogamous. However, despite the steep allogamy, self-pollination can occur in a small proportion (Gribel and Hay 1993; Martins and Gribel 2007).

The flowering usually occurs between August and November, depending on the region, and the fruit ripening takes from 3 to 4 months after the pollination, with low fruit set rate. However, according to Araújo (1995), one Pequi plant can produce 500–2000 fruits/harvest.

Pequi’s fruit is a drupe type with depression-globular shape, leathery and fleshy epicarp, and bright green/slightly yellowish color when ripe, with burry endocarp. Its dimensions range from 4 to 7 cm high and 6–8 cm in diameter, with average mass reaching approximately 120 g, but with variation from 100 to 220 g (Araújo 1995, Lorenzi and Matos 2008).

The pulp is oleaginous, mealy and pasty, varying in color from cream-yellow to intense-yellow and sometimes orange. Generally, the fruit contains only one seed developed (putamen or pyrene), but sometimes it can contain up to three or four seeds (Araújo 1995; Silva and Medeiros Filho 2006; Oliveira 2009).

4 Geographical Distribution

Therefore, C, coriaceum, specie found in the northern of Ceará, has an important socio-economic role in Chapada do Araripe, covering the States of Ceará, Pernambuco and Piauí. Can also be found in the states of Tocantins and Maranhão (Saraiva et al. 2011).

5 Collection Practice

Thus, C. coriaceum is explored in an extractive way, being seasonal, with flowering from September to November and the season between December and April, period of high rainfall in the region. Then in the off-season, there is the extraction of oil from the pulp and almond, which has greater commercial value (Costa et al. 2004; Lorenzi and Matos 2002).

In pequi’s harvest period, the communities near Chapada do Araripe perform extractive activities, collecting fruit for marketing. The fruit is not collected directly from the tree; it is collected after fruit falls to the ground because the taste of the fruit pulp collected from the “floor” is much better (Augusto and Goes 2007; Sousa Junior 2012).

6 Traditional Use (Part(s) Used) and Common Knowledge

However, pequi has a large emphasis in traditional medicine context, highlighted as a relevant ethnopharmacological resource. For example, pequi’s bark of the tree and skin of the fruits are used in antipyretic and diuretic infusions (Lorenzi and Matos 2008).

The fruit has anti-abortive and aphrodisiac properties and the leaves are used to treat colds, flu, edemas, menstrual changes and as an antifungal (Vieira and Martins 2000; Batista et al. 2010).

In this context, oil is used in the treatment of burns, colds, broncho-pulmonary infections, skin ulcers, inflammation of the skin and musculoskeletal pain (Saraiva 2009).

At the same time, reports show its use in ophthalmic disorders related to vitamin A deficiency, by its high content of carotenoids with provitamin A activity (Santos 2007; Oliveira et al. 2008).

Furthermore, pequi’s fruit is almost fully used, because the skin is consumed by bovine animals, the seed (with pulp) is used in the preparation of dishes – quite appreciated in regional food – and the pulp is still used for extraction and homemade or manufacture edible oil, jellies, jams, liqueurs and animal food (Lorenzi and Matos 2008; Oliveira 2009).

The almond, due to its high nutritional value, shape, size and visual appearance, is also used for fresh consumption in the oil extraction and soap manufacturing, and in cosmetics industry as creams and soaps, being potential as another option in the national market of almonds (Lorenzi and Matos 2008; Oliveira 2009).

Therefore, the therapeutic value of pequizeiro to popular medicine has been researched and some ethnopharmacological and ethnobotanical studies show its real effectiveness, emerging an important bioprospecting research (Batista et al. 2010; Lorenzi and Matos 2008).

7 Modern Medicine Based on Its Traditional Medicine Uses

In the essence of published studies about the medicinal uses of pequi, as well as several other species of traditional use, there is the technique of bioprospecting. Therefore, bioprospecting is basically the identification and evaluation of specific biological material extracted from nature, for its applicability and utility in generating new processes and products. Thus, resources found in nature are experienced, seeking to obtain new resources to be used in everyday life (Palma and Palma 2012).

In the contemporary view of bioprospecting, there are environmental and social aspects associated with new economic paradigms. That is, it is related to biotechnology, with the “biodiversity” and with the agents directly and indirectly involved with the completion of this activity, as entrepreneurs, local communities, indigenous groups, environmental groups, research institutions, international organizations, among others (Palma and Palma 2012).

Bioprospecting also allows the identification of priorities relating to lines of research or for the strengthening of old research. In this sense, some bio-prospective studies nationally and internationally published, corroborate the therapeutic uses of pequi in the Traditional Medicine context (Lorenzi and Matos 2008).

For example, as in some studies in general, there is Passos et al. (2002) research performed with the extract of pequi’s leaves, finding antifungal activity by inhibiting the growth of Cryptococcus neoformans, Paracoccidioides brasiliensis and Candida albicans.

In addition, molluscicidal action against Biomphalaria glabrata (schistosomiasis vector) was identified in Batista et al. (2010) research, leishmanicide effect by inhibiting the proliferation of the promastigote form of Leishmania amazonensis and antimicrobial activity by inhibiting the growth of enterobacteria, according to studies of Paula-Junior et al. (2006).

It is important to mention the research of Alves et al. (2000) showing actions against Bacillus cereus, Pseudomonas aeruginosa and Staphylococcus aureus.

Interference with T. cruzi parasitemia curve has been demonstrated in pequizeiro bark extract, thus reducing the number of parasites in the blood (Herzog-Soares et al. 2002).

In this sense, antioxidant and preventive activities for tumors were also observed (Paula-Junior et al. 2006; Khouri et al. 2007), effects against Sarcoma in animals by oleanolic acid content and protease and evidence of hemolytic activity of C. brasiliense lectin, as well as in vivo enterotoxic activity in mice (Perez 2004).

It is also noteworthy that pequi’s oil is a rich source of vitamin C, with phenolic compounds such as flavonoids, saponins and essential oils in the mesocarp (Miranda-Vilela et al. 2008).

On the other hand, these components have antioxidant properties, mitigating the effects of mutagens and carcinogens agents. In addition, oxidative stress is one of the major risk factors for cardiovascular disease (Alonso 2000; Miranda-Vilela et al. 2008; Tseng et al. 2004).

Furthermore, preclinical studies of C. coriaceum fixed oil indicate the gastro-protective activity in rodents with a significant reduction of ulcers induced by ethanol and aspirin, besides to healing activity, topical anti-inflammatory effect in mice, and reduction of skin inflammation, with chronic treatment (Penha 2007; Quirino 2009; Saraiva 2009).

The main compound of fixed oil from the pulp of C. coriaceum (OFCC) is the unsaturated fatty oleic acid. The saturated fatty acids increase low-density lipoprotein (LDL) by inhibiting LDL receptor activity and increase the production of apolipoprotein (Aguilar et al. 2012).

In this way, the substitution of saturated fat by poly-unsaturated fat has reduced levels of total cholesterol (TC) and LDL cholesterol levels, decreasing LDL-cholesterol production rates and/or increasing LDL clearance rates (Aguilar et al. 2012).

On the other hand, there is a decreasing in high density lipoprotein (HDL), which together with the reduction in LDL-c, LDL/HDL ratio decreases. Monounsaturated fat also has the same effect on blood cholesterol but the magnitude of the reduction in HDL is lower when compared to poly-unsaturated fats (Aguilar et al. 2012).

In this context, it is important to detail these and some other published studies, such as Saraiva et al. (2011) research assessing the topical effect of C. coriaceum against different irritant agents in vivo, in order to verify its effect against dermatoses.

Therefore, Saraiva et al. (2011) research found that the species showed a similar profile of topical anti-inflammatory activity, indicating its potential use against inflammatory skin diseases.

In the study by Oliveira et al. (2010), it was sought to evaluate the effects of the C. coriaceum fixed oil (OFCC) on topical inflammation and cutaneous wound healing. In this way, the tests showed that the OFCC was able to reduce inflammation depending on the doses.

Fresh OFCC (100%) inhibited ear edema in 38.01% at the time of 15 min and in 39.20% in 1 h, after induction of the inflammation. Topical administration of OFCC ointment (12%) showed a significant reduction in the unhealed wound area, with the increase in the percentage of wound contraction (96.54%) compared to the other groups. Thus, the conclusion was that C. coriaceum inhibits topical inflammation and speeds up the repair of skin wounds.

In Oliveira’s research (2013) the antinociceptive activity and anti-inflammatory pequi oil in zymosan-induced arthritis in rats was investigated. The author states that besides the detected anti-inflammatory action, pequi’s oil can prevent the inflammatory mechanical hyperalgesia.

On the other hand, in the study of Lacerda Neto (2013), the objective was to verify the gastro-protective activity of a hydroethanolic extract of C. coriaceum leaves (EHFCC). Thus, EHFCC gastroprotective activity was evaluated by methods of gastric damage induced by ethanol and a reduction of the lesion area of 69.43% was observed.

Furthermore, quantification of mucus production showed that EHFCC positively influences it and the intestinal motility test reported a decrease in motility under EHFCC action, being as another contribution to its gastro-protective effect (Lacerda Neto 2013).

Thus, the author concludes by highlighting that the described results show the biological potential of EHFCC as a grant for the study of gastro-protection and especially in the formulation of new herbal medicines for the treatment of peptic ulcer (Lacerda Neto 2013).

In C. coriaceum influences for cardiovascular diseases, Figueiredo’s study (2012) evaluated the toxic effects of C. coriaceum fixed oil in biochemical and histopathological parameters of rodents. From the results, the author showed that sub-chronic toxicity was not revealed at high doses for the evaluated parameters.

Furthermore, it was demonstrated anti-inflammatory and antioxidant activity of C. coriaceum fixed oil. The importance of this study was also due to be the first study to report a possible lipid-lowering and hypo-triglyceride activity of coriaceum species, showing species with a pharmacological potential related to the management and treatment of cardiovascular diseases, world problems of epidemiological importance (Figueiredo 2012).

Thus, from this information, it can be said that the large and reputable popular use of pequi in Traditional Medicine is supported by the available scientific literature, although further studies to clarify other therapeutic actions of Pequi are necessary for ethnobotanical surveys.

8 Conclusions

The importance of C. coriaceum or pequi to traditional communities is not only in the economic context, but also in the context of practices related to Traditional Medicine.

During this chapter, the therapeutic use of pequi was highlighted as being widespread and accepted among the local population of Chapada do Araripe and surrounding regions. Therefore, it is used for a variety of pathologies, suggesting that this species is inserted in a complex set of culturally relevant plants.

However, it is observed that there are a few published studies concerning the applicability of this plant as a viable or complement alternative to conventional pharmacological treatment used for different diseases, ranging from skin diseases to cardiovascular diseases.

In fact, new bioprospective studies should be conducted, addressing chemical, pharmacological characteristics and clinical applicability of C. coriaceum species, in order to an efficient use of the properties provided by this plant.