**6. Health effects of some Surinamese Fabaceae and relationship with phenolic antioxidants**

#### **6.1** *Caesalpinia pulcherrima* **(L.) Sw**

The peacock flower or krerekrere *C. pulcherrima* (L.) Sw. (**Figure 2**) is an evergreen shrub that grows to 3 m tall and likely originates from Mexico and the Caribbean, but can now be encountered in all tropical and subtropical parts of the Americas. Its beautiful inflorescence in yellow, red, and orange has made it a generally valued ornamental plant and the national flower of the Caribbean island of Barbados. The mature seeds contain cyanide and are poisonous, but the immature seeds are edible after roasting [126]. As the taste seems reminiscent of that of peanuts, another Surinamese vernacular for *C. pulcherrima* is "jodenpinda," meaning "the peanut of the Jews," in reference to the colonial masters from Jewish ancestry on whose plantations the enslaved Africans had come to know the plant [127].

Preparations from various parts of *C. pulcherrima* are used as a mouthwash for teeth and gums; as an emmenagogue, to accelerate childbirth, and as a strong abortifacient; for treating colds and fevers; against gastrointestinal complaints such as diarrhea, constipation, and gall bladder problems; and to remedy urinary tract problems such as kidney stones [128, 129]. In Suriname, C. *pulcherrima* is used for the same purposes [118, 120, 125] but also for good fortune and to honor Mama Aisa, an important deity in Afro-Surinamese Winti religion [130].

Phytochemical investigations have revealed the presence of various bioactive constituents in *C. pulcherrima* including a variety of flavonoid compounds along with glycosides,

*Phenolic Compounds and Antioxidant Activities of Eight Species of Fabaceae… DOI: http://dx.doi.org/10.5772/intechopen.106076*

#### **Figure 2.**

*Flower of the peacock flower or krerekrere* Caesalpinia pulcherrima *(L.) Sw. (from: https://images.app.goo.gl/ bqSv1gehtAQT11uk8).*

alkaloids, terpenoids, and sterols [131–133]. Some of these compounds have been associated with pharmacological activities such as antimicrobial, analgesic, anti-inflammatory, and cytotoxic activities, supporting some of the traditional uses of the plant [132–134].

Preparations from several parts of *C. pulcherrima* also exhibited substantial antioxidant activity [134–136]. Studies with this plant and other species of *Caesalpinia* have suggested that this activity may be associated with, among others, anti-inflammatory activity [135, 136], the inhibition of prostaglandin biosynthesis [135], the inhibition of nitric oxide production [136, 137], and/or the stimulation of superoxide dismutase and catalase activity [137]. These activities might be attributed to the phenolic compounds in the plant [136, 138, 139], supporting a role of these substances and their antioxidant activities in its apparent health-promoting effects.

#### **6.2** *Cajanus cajan* **(L.) Millsp.**

The pigeon pea or loangopesi *C. cajan* (L.) Millsp. (**Figure 3**) is an erect, woody shrub that grows to a height of about 4 meters and that is native to the Old World [140]. It is not known in the wild but has been cultivated for centuries in tropical and subtropical regions of the world for its edible, protein-rich seeds, its medicinal properties, as well as its usefulness as fuel, a green manure, and for soil stabilization [140]. This plant is believed to have reached the New World including Suriname by means of the Trans-Atlantic slave trade at the end of the seventeenth century [141]. It grows relatively fast, is rather resilient, easily adapts to different soil and climatic conditions, and is drought-resistant [142], which makes it of utmost importance for food security in areas where rainfall is not reliable and droughts are likely to occur [143]. Not surprisingly, *C. cajan* has become part of the daily staple meals of millions of people throughout the world [140].

Humans have also used *C. cajan* since long medicinally, among others, for oral hygiene and treating oral complaints such as gingivitis and stomatitis, and ulcers and inflammations in the oral cavity, skin problems, as well as various chronic diseases such as diabetes mellitus [144–146]. In Suriname, the fresh leaf is squeezed into inflamed eyes [117] and incorporated into an infusion to facilitate childbirth [117] and to stop severe vomiting [118]. The potential therapeutic efficacy of these

#### **Figure 3.**

*Seedpods of the pigeon pea or loangopesi* Cajanus cajan *(L.) Millsp. (from: https://images.app.goo.gl/ k6pETr1KXfuioSte8).*

traditional remedies is partially supported by the results from pharmacological studies showing remarkable anti-inflammatory activity of preparations from several parts *C cajan* in both cell culture and animal models [147–150].

These observations have been attributed to the prevention of lipid peroxidation, the stimulation of endogenous antioxidant enzyme activities, and/or a decrease in the production of inflammatory cytokines [148–150]. The phytochemicals that have been held responsible for these activities were flavonoids [148–150], which was in accordance with the high phenolic content of *C. cajun* that included a diversity of flavonoids, tannins, coumarins, and stilbenes [147, 151]. Notably, flavonoid and phenolic contents of the plant samples correlated well with their individual antioxidant activity [149, 152]. Based on these data, *C. cajan* has been proposed as a candidate for skin care research and development [151].

#### **6.3** *Clitoria ternatea* **L.**

The butterfly pea *Clitoria ternatea* L. is a perennial herbaceous climber that is native to tropical equatorial Asia, but can now also be found in Africa, Australia, and the Americas including Suriname. The genus name "*Clitoria*" has been derived from the presumed resemblance of the strikingly blue flowers with light yellow markings to the shape of human female genitals (**Figure 4**). This is also captured in the Indonesian/Malay vernacular of the plant "kembang telang," "kembang" meaning "blossoming," "swollen," or "extended," and "telang" meaning "blue-colored flower." The blue color of the flower is caused by its high content of ternatins, polyacylated derivatives of the anthocyanin delphinidin 3,3′, 5′-triglucoside [153]. It is used in south-eastern Asia as a natural coloring for rice dishes, desserts, hot and cold beverages, and textiles for making clothing. The attractive flower also makes the plant a well-appreciated ornamental in many parts of the world. Other notable chemical components in *C. ternatea* are cyclotides, exceptionally stable macrocyclic peptides present in all tissues of this plant [154]. These compounds are the bioactive molecules in a commercial eco-friendly insecticide developed from this plant [155].

*Phenolic Compounds and Antioxidant Activities of Eight Species of Fabaceae… DOI: http://dx.doi.org/10.5772/intechopen.106076*

#### **Figure 4.**

*Flower of the butterfly pea or kembang telang* Clitoria ternatea *L. (from: https://images.app.goo.gl/ dtytS8JnGZBEzhPg9).*

In traditional Chinese medicine, *C. ternatea* is used to increase female libido [156]. And in Indian Ayurveda, preparations from the plant are believed to enhance memory, improve cognitive function, control or prevent seizures, relieve stress, prevent or treat anxiety and depression, and exert calming and sedative effects [157]. These effects might be associated with the modulation of serotonin and acetylcholine metabolism in the brain [158]. In Suriname, *C. ternatea* is mainly used by the Javanese, who pour the diluted sap from the macerated leaf into inflamed eyes [118].

A variety of preclinical studies have shown that extracts from *C. ternatea* display a wide range of pharmacological activities including antimicrobial, antipyretic, antiinflammatory, analgesic, diuretic, local anesthetic, antidiabetic, insecticidal, blood platelet aggregation-inhibiting, and vascular smooth muscle-relaxing properties [157, 159]. Many of these activities have been attributed to the presence of flavonols (in the form of flavonol glycosides) and anthocyanins in the plant [159]. These compounds could elicit some of the abovementioned pharmacological activities through their well-documented antioxidant effects [160, 161] or by contributing to the pharmacological activities of other bioactive compounds in the plant [159].

For instance, the anthocyanin delphinidin 3-sambubioside (from the dried calices of the roselle *Hibiscus sabdariffa* L.; Malvaceae) elicited anti-inflammatory activity in both cell and animal models [162], the synthetic cyclotide [T20K]kalata B1 delayed disease progression and diminished symptoms in a mouse model of multiple sclerosis [163], and the pentacyclic triterpenoid taraxerol isolated and purified from extracts of the transformed root somaclones of *C. ternatea* displayed encouraging anticancer properties [164]. Interestingly, the antioxidant properties of *C. ternatea* have commercially been utilized by including extracts from the flower in antiaging cosmetic products [165].

#### **6.4** *Copaifera guyanensis* **Desf.**

The copaiba or hoepelhoutboom *Copaifera guyanensis* Desf. is an evergreen tree with a thick trunk that grows to about 25 m tall and that is indigenous to the swamps and rainforests of northern South America including Suriname (**Figure 5**). *C. guyanensis* is much in demand for the oleoresin in the grayish-brown bark of the trunk.

#### **Figure 5.**

*Seedpods of the copaiba or hoepelhout* Copaifera guyanensis *Desf. (from: https://images.app.goo.gl/ G6iLQWMFEEfyPR8D8).*

The oleoresin is a transparent, yellow to light brown liquid consisting of a nonvolatile fraction and a volatile essential oil with a scent that has been described as woody, sweet, and balsamic [166, 167]. The oleoresin is harvested by drilling a hole in the trunk of the tree and collecting it with the help of a polyvinyl chloride pipe, after which the borehole is plugged in order for the tree to sufficiently recover to retap it a year later. The oleoresin is used in small amounts as a food additive and as a flavoring agent in foods and beverages and has officially been approved in the USA for these purposes (see, for instance, [168]). It is also an ingredient of perfumes, varnishes, and lacquers and used as a substitute for diesel oil [169–171]. Given the latter application, *C. guyanenesis* is also called "diesel tree." The flexible but tough heartwood has been used for preparing hoops to tightly press the staves of barrels against each other, achieving watertight containers to store sugar. Hence, the Surinamese vernacular "hoepelhout," literally meaning "wood for constructing hoops" [125].

*C. guyanansis* oleoresin (as well as that of other *Copaifera* species) has a very long history of medicinal use. In fact, the Amazonian Indigenous peoples have known the healing properties of the oleoresins for centuries from their observation that injured animals rubbed themselves on the tree's trunk to heal their wounds [169, 172]. This led to the use of the oleoresin against, among others, microbial infections and inflammations and as a disinfectant, styptic, and wound-healing stimulatory substance [166, 173]. Other indications of *C. guyanensis* oleoresin are a sore throat, tonsillitis, bronchitis, and tuberculosis; cystitis, kidney and bladder infections, vaginal discharge, and gonorrhea; stomach ulcers; as well as a variety of skin problems including insect bites, eczema, blisters, sores, and psoriasis [167, 169, 174]. *C. guyanansis* oleoresin has essentially the same traditional uses in Suriname, where, in addition, a tea from the bark is drunk against diabetes mellitus, hypertension, malaria, and jaundice [125].

The principle pharmacologically active ingredients in the volatile essential oil of *C. guyanensis* oleoresin are sesquiterpenes, most notably β-caryophyllene, while the nonvolatile fraction mainly consists of acid diterpenes such as copalic acid and kaurenoic acid [166, 173]. Particularly β-caryophyllene displayed substantial antiseptic, anti-inflammatory, and antimicrobial effects including activity against *Staphylococcus aureus* [166, 167, 175], a common cause of skin infections. For these

*Phenolic Compounds and Antioxidant Activities of Eight Species of Fabaceae… DOI: http://dx.doi.org/10.5772/intechopen.106076*

reasons, the cosmetic industry extensively uses *Copaifera* oleoresins in anti-acne creams, formulations for treating stretch marks and scars, as well as shampoos, capillary lotions, soaps, and bathing foams [176]. β-Caryophyllene also selectively binds to the cannabinoid receptor 2 [177], which makes it an interesting candidate to relieve pain and inflammation [176, 178]. The diterpenes from *Copaifera* oleoresins reportedly elicited *in vitro* antibacterial, anti-inflammatory, antileishmanial, antitrypanosomal, and wound-healing stimulatory activities [179]. These findings substantiate some of the traditional uses of *C. guyanenesis*, but so far there are no convincing data on the usefulness of *Copaifera* oleoresins in the clinic (see, for instance, reference [178]).

There are also reports on antioxidant activity of *Copaifera* species. For instance, the oleoresin from *C. langsdorffii* Desf. elicited notable antilipoperoxidation, antioxidant, and anti-inflammatory activity in an experimental model of random skin flaps on rat dorsums [180]. In addition, the essential oil from *C. officinalis* L. seed reduced lipid oxidation, showing promise as a natural antioxidant to increase the shelf life of meat products [168]. This effect has tentatively been attributed to the phenolic compounds identified in the essential oil [168]. Phenolic compounds—particularly flavonoids—have also been detected in the fruit and leaf of several *Copaifera* species [181, 182]. However, at this moment, there is no hard evidence to associate phenolic compounds and their potential antioxidant activities with the traditional uses and pharmacological activities of *Copaifera* species.

#### **6.5** *Desmodium adscendens* **(Sw.) DC**

The glue sticks *D. adscendens* (Sw.) DC is a creeping or ascending herbaceous perennial herb or low shrub that can grow up to 1 meter in height. It probably originates from Africa, but is now widespread in tropical areas of Asia, South and Central America, and the Caribbean. The presence of many small hooked hairs on the seedpods (**Figure 6**) makes them cling to clothing, body parts, as well as the feathers and coats of pollinating animals, ensuring a wide dispersal of the plant. Hence, the vernacular "glue stick" in English and "konkruman" ("informer") in Suriname: the sticky pods attaching to

#### **Figure 6.**

*Seedpods of the glue sticks or konkruman* Desmodium adscendens *(Sw.) DC. (from: https://images.app.goo.gl/ CoBQwXQrRHUgXq4e9).*

clothing betray the unapproved presence of the bearer "in the field," that is, away from home [183]. The plant is also believed to attract and hold fortune and prosperity while at the same time capturing and removing bad luck and disease [125].

Leaf, stem, and root of *D. adscendens* (as well as parts of the closely related species *Desmodium barbatum* (L.) Benth. and *Desmodium incanum* (Sw.) DC) have probably been used for thousands of years by native peoples of the Americas for a variety of health issues, including asthma and allergies; muscle cramp and back pain, rheumatism; venereal diseases, vaginal infections, and ovarian inflammation; epilepsy; hypertension; and diabetes mellitus [184, 185]. In Suriname, preparations from *D. adscendens* leaf, stem, and root are taken to relieve abdominal pain, fever, and painful urination associated with venereal diseases and as a remedy against diabetes mellitus and hypertension [124].

*D. adscendens* is rich in phenolic compounds including flavonoids, anthocyanins, and tannins, as well as reducing sugars, alkaloids, (soya)saponins, triterpenes, and amines [185, 186]. The meaningful pharmacological activities displayed by some of these compounds—such as anti-asthmatic and anti-anaphylactic activity [187, 188] and antihypertensive activity [183]—may support some of the traditional uses of the plant.

There are also reports associating the appreciable content of phenolic compounds with its antioxidant activity and some of its pharmacological effects. For instance, astragalin, the 3-O-glucoside of the flavonoid kaempferol, displayed antioxidant, anti-inflammatory, and anti-atopic dermatitis activity and attenuated lipopolysaccharide-induced inflammatory responses by suppressing the NF-кB signaling pathway [189]. Astragalin also elicited antibacterial activity [190], which may explain the abovementioned traditional uses of the plant for treating infections, venereal diseases, and wounds [124, 184, 185]. Moreover, leaf and whole-plant extracts from *D. adscendens* displayed ROS scavenging activity and antioxidant properties *in vitro* [186]. These preparations also protected an LLC-PK1 pig kidney epithelial cell line from glucose-induced oxidative stress [191] and hepatocytes from carbon-tetrachloride-induced injury and hepatitis C virus infection [192]. These observations support the possibility that the antioxidant properties and the phenolic compounds of *D. adscendens* may be associated with its potential therapeutic value.

#### **6.6** *Dipteryx odorata* **(Aubl.) Willd**

The tonka bean or tonkaboon *D. odorata* (Aubl.) Willd. (**Figure 7**) is a large semideciduous tree with a small, rounded crown that generally grows up to 30 m tall and that is native to Central America and northern South America. The tree is sometimes cultivated but is mostly harvested from the wild for its seed that is rich in coumarin [193]. The tonka beans are black and wrinkled, and have a smooth, brown interior, and their high content of coumarin and several of its derivatives such as umbelliferone (7-hydroxycoumarin) give them a strong sweet and spicy fragrance that is reminiscent of vanilla and almond [193]. For this reason, coumarin is abundantly used in the perfume industry as a fragrance and in desserts and stews as a substitute for vanilla [194]. However, at large infused doses, coumarin may cause liver damage, hemorrhages, and paralysis of the heart [195]. It is therefore controlled as a food additive by many governments [194] and has even been banned in the USA [196]. Anticoagulant prescription drugs such as warfarin are based on 4-hydroxycoumarin that was initially isolated from *D. odorata* seed, but coumarin itself does not have anticoagulant properties [197]. Other non-medical applications of coumarins are their use as agrochemicals, *Phenolic Compounds and Antioxidant Activities of Eight Species of Fabaceae… DOI: http://dx.doi.org/10.5772/intechopen.106076*

#### **Figure 7.**

*Flowering tonka bean or tonkaboon* Dipteryx odorata *(Aubl.) Willd. (from: https://images.app.goo.gl/ Yy9nodcJhZr5mwvG9).*

materials for food processing, optical brighteners, and dispersed fluorescent and laser dyes (see, for instance, references [198, 199]).

Despite the safety concerns, the seed and various other parts of *D. odorata* are traditionally used, among others, to fortify the scalp and improve hair growth; as a remedy for colds, fever, coughing, asthma, and tuberculosis; for treating stomach pain and diarrhea; against dysentery and schistosomiasis; as an emmenagogue, and as an aphrodisiac [200, 201]. In Suriname, *D. odorata* seed is mainly used as an ingredient of products to treat hair loss, dandruff, and an itching scalp; against colds; and to command luck [125, 202].

Some of the traditional uses of *D. odorata* are supported by the results from studies with various coumarin analogues—from the seed as well as other parts of the plant showing a wide range of pharmacological activities such as antimicrobial, antituberculosis, antiviral, anticoagulant, anticancer, anti-inflammatory, and antioxidant activities [194, 203]. In addition to coumarin, *D. odorata* seed contains various other bioactive flavonoids, particularly isoflavones [204], particularly in the endocarp [205] as well as some of its other parts [206, 207]. These compounds are known to elicit potent antioxidant activity [208] and are, similarly to coumarins, phenylpropanoidderived natural products. However, so far, their presence in *D. odorata* has neither been associated with antioxidant activity nor with the traditional and pharmacological activities of preparations from the plant.

#### **6.7** *Lablab purpureus* **(L.) Sweet**

The hyacinth bean *L. purpureus* (L.) Sweet (**Figure 8**) is an annual or short-lived perennial vine of approximately 6 m high that is presumably native to Africa and has been introduced in south-eastern Asia where it has been cultivated as early as 2500 BC [209]. Since then, it has been carried to many tropical and subtropical parts of the world including Suriname, where it has been brought by Hindustani indentured laborers around the end of the nineteenth century [124]. Hence, its Surinamese vernacular "kulibontyi," literarily meaning "the bean of the coolies," the epithet used for Hindustanis in that period. *L. purpureus* is commercially cultivated as an edible

#### **Figure 8.**

*Seedpods of the hyacinth bean or kulibontji* Lablab purpureu*s (L.) sweet (from: https://images.app.goo.gl/ EpBr6jHWi2s63vEHA).*

plant, as forage for livestock, and as an ornamental. The seed is poisonous due to its high content of toxic cyanogenic glucosides and trypsine and must thoroughly be cooked to destroy the toxin before consumption [210].

Preparations from various parts of the plant are used for a wide range of medicinal applications, ranging from remedies for alcohol intoxication and insufficient libido to medications for hypertension, high cholesterol, and diabetes mellitus [211, 212]. In Suriname, this plant is mainly used by Hindustanis, who apply the macerated leaves as a poultice against the fungal skin infections pityriasis versicolor and ringworm [124]. Pharmacological studies have shown, among others, anti-inflammatory, analgesic, antidiabetic, antimicrobial, antihypertensive, and anticancer activities [213, 214]. These activities may be associated, at least in part, with the presence in the plant of a variety of pharmacologically active constituents including phenolic compounds such as the flavonoids isoflavone, kievitone, and genistein [212, 215, 216]. In studies with other plants, some of these compounds reportedly decreased the production and the release of arachidonic acid, the expression of cyclooxygenase-1, cyclooxygenase-2, and 15-lipooxygenase, as well as the production of downstream-situated inflammatory mediators such as nitric oxide and prostaglandin E2, eliciting anti-inflammatory activities [217–220]. Whether the phenolic compounds in *L. purpureus* also elicit these activities is not certain. But should that be the case, they can account for the traditional uses of the plant as well as the interest of the pharmaceutical industry to develop them to medicinal foods, nutraceuticals, and pharmaceuticals [211, 221].

#### **6.8** *Tamarindus indica* **L.**

The tamarind or tamarinde *T. indica* is a long-living fruiting tree with a dense, spreading crown that can reach a height of 30 m. It is probably indigenous to tropical Africa where it grows in the wild. The tree has been cultivated for centuries in the tropics and subtropics as an ornamental plant, for its edible seedpods (**Figure 9**), and for its many medicinal uses. It has presumably been introduced in Suriname by enslaved Africans in the seventeenth century in order to fight diseases such as fever,

*Phenolic Compounds and Antioxidant Activities of Eight Species of Fabaceae… DOI: http://dx.doi.org/10.5772/intechopen.106076*

#### **Figure 9.**

*Seedpods of the tamarind or tamarinde* Tamarindus indica *L. (from: https://images.app.goo.gl/ FJZ5FyY8UrNma1QUA).*

diarrhea, and worm infections on the slave ships [141]. *T. indica* produces pods with a hard, brown shell that contain about 10 seeds surrounded by a sour pulp that is rich in tartaric acid, acetic acid, and citric acid and is used in cooking, to flavor foods, in refreshing drinks, and as a key ingredient of Worcestershire sauce.

Preparations from *T. indica* leaf, seed, fruit, stem bark, and root are extensively used in folk medicine, among others, for treating abdominal complaints, to stimulate wound healing, to treat microbial and parasitic infections, against various skin diseases, to fight various inflammatory ailments, and as a remedy for hypertension and diabetes mellitus [222, 223]. In Suriname, *T. indica* preparations are used for the same conditions but also against menstrual pain and excessive vaginal discharge [117, 121]. Some of the traditional uses are supported by the results from pharmacological studies showing anti-inflammatory, analgesic, antimicrobial, antiviral, antihypertensive, antidiabetic, and anticancer activities in several laboratory models (see, for instance, references [224–226]).

Some of these activities may be attributable to the presence in the plant of pharmacologically active ingredients with notable antioxidant properties such as phenolic compounds [224–227] including tannins [227, 228], as well as selenium [229], and ascorbic acid and ß-carotene [228]. The antioxidant activity of *T. indica* preparations has been associated with, among others, their antidiabetic, hypolipemic, and antihypertensive effects in laboratory animals [230–232]. Thus, several of the traditional uses and pharmacological activities of *T. indica* may be partially associated with the presence in the plant of phenolic compounds with antioxidant activity.

### **7. Concluding remarks**

Parts from species in the Fabacaeae plant family are among the most commonly used ingredients in Surinamese traditional medical practices and are employed for a wide diversity of medical indications. In this chapter, we have determined whether the abundant medicinal use of these plants may be associated with their phenolic

content and antioxidant activity. This was based on the association of the Fabaceae family with these properties [93–102], even though phenolic antioxidants have been found in a relative handful of the roughly 20,000 plant species in this family that have scientifically been evaluated [93–102]. The plants assessed in the current chapter were *C. pulcherrima*, *C. cajan*, *C. ternatea*, *C. guyanensis*, *D. adscendens*, *D. odorata*, *L. purpureus*, and *T. indica* (**Table 1**). For six of these plants—*C pulcherrima*, *C cajan*, *C. ternatea*, *D. adscendens*, *L. purpureus*, and *T. indica*—the traditional uses and pharmacological activities could be attributed, at least in part, to their phenolic compounds (more specifically, their flavonoids) and the notable antioxidant activities of these substances (**Table 1**). However, the traditional uses and pharmacological activities of *C. guyanensis* mainly seemed to be determined by terpenoids which did not elicit antioxidant activity (**Table 1**). And those of *D. odorata* mainly seemed to involve coumarins, which, although classified as phenolic compounds, did not seem to act *via* antioxidant activity (**Table 1**). This argues against the characterization of the Fabaceae as "a plant family of antioxidant phenolic compounds" [93–102] and underscores the necessity to further explore this group of plants for other classes of phytochemicals and other so far unknown but potentially useful pharmacological activities.
