**3.4. Apiaceae –** *Apium graveolens* **L.**

**Figure 3.** Annonaceae – *Annona muricata* L. (from: https://goo.gl/images/K9WNHr).

rats [67].

164 Herbal Medicine

**3.3. Annonaceae –** *Annona muricata* **L.**

*cata* extracts against cultured cancer cells [68].

Preparations from flowers, unripe fruits, stone, leaves, stembark, and roots of *M. indica* also have many traditional medicinal uses, among others, to treat certain parasitic infections, uterus disorders, gastrointestinal problems, and syphilis; strengthen the blood vessels; cure varicose veins; and lower an elevated blood pressure [46, 62–64]. Several of these properties have been attributed to a number of bioactive substances in leaves and stem bark of the plant including the polyphenolic compound mangiferin [65]. This compound also displayed notable blood pressure-lowering effects in *in vitro* models and laboratory animals [66].

The apparent antihypertensive effect of *M. indica* preparations and constituents may be attributed to at least two mechanisms, namely the induction of vasodilation and the stimulation of diuresis. Indications for the former possibility are provided by the inhibition of noradrenalineinduced contractions of mesenteric arteries isolated from spontaneously hypertensive rats by a *M. indica* stem bark extract (called 'Vimang' from 'vida del mango' meaning 'life of the mango') [62]. Support for the second possibility comes from the diuretic effect of 'Vimang' in laboratory

The exact origin of the soursop or graviola *A. muricata* (**Figure 3**) is unknown, but it is believed to be native to the Caribbean and the tropical regions of the Americas. It is now widely cultivated for its fruit, the pulp of which contains substantial amounts of vitamin C, vitamin B1, and vitamin B2 and is used to make fruit juice drinks, smoothies, as well as candies, sorbets, and ice cream flavorings. Relatively recently, *A. muricata* fruit and graviola capsules have been promoted as an alternative treatment for cancer. However, there is no medical evidence for such an activity, even though preclinical studies have shown cytotoxic effects of *A. muri-*

Importantly, *Annona* species including *A. muricata* are a rich source of annonaceous acetogenins such as annonacin and annonamine, potent neurotoxins that inhibit mitochondrial

> The celery *A. graveolens* (**Figure 4**) originates from the Mediterranean region, but many cultivars are now grown throughout the world. This plant has been cultivated since ancient times, initially only for its medicinal qualities, but later also as a vegetable to counter the salt-sickness of winter diets based on salted meats without green vegetables. Today, *A. graveolens* stalks, leaves, and hypocotyl are eaten raw or as an ingredient in salads, cooked as a vegetable, or as a flavoring – either fresh or dried – in soups, stews, and pot roasts.

> *A. graveolens* seeds – which are in fact very small fruits – yield a valuable volatile oil that is used in perfumes and, when ground and mixed with salt, to produce celery salt for enhancing the flavor of, for instance, Bloody Mary cocktails [77]. However, celery seeds contain relatively high levels of the phenylpropene apiole that can cause abortion – sometimes with fatal consequences [78] – as well as liver and kidney damage [79] and severe allergic reactions including potentially fatal anaphylactic shock [80].

Almost all parts of *C. nucifera* have long been used in traditional medicine for treating many disease conditions, among others, diarrhea, fever and malaria, renal diseases, asthma, diabetes mellitus, hair loss, menstrual disorders, venereal diseases, as an oral contraceptive, and against hypertension [45, 94]. Pharmacological studies with extracts, fractions, and isolated compounds from parts of *C. nucifera* indeed showed a variety of activities ranging from antimicrobial and antiparasitic activities to vasodilatory and antihypertensive effects [95]. Some of these observations may be related to the presence in the plant of polyphenols, tannins,

Plant-Based Ethnopharmacological Remedies for Hypertension in Suriname

http://dx.doi.org/10.5772/intechopen.72106

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Evidence for an antihypertensive activity from *C. nucifera* came from the relaxation of isolated rat aortic rings by an ethanolic extract of *C. nucifera* endocarp and the reduced blood pressure in salt-induced hypertensive rats treated with this preparation [96]; the decreased blood pressure in a rat model of insulin resistance and acquired systolic hypertension following administration of tender coconut water [97]; and the decrease in heart rate of hypertensive Wistar rats which were given coconut water [98]. Notably, in a small clinical study, coconut water given for 2 weeks reportedly lowered the blood pressure in 71% of hypertensive individuals [99], while the fresh vascular sap from the immature, unopened inflorescence given once per day for 5 consecutive weeks led to a decrease in blood pressure as well as a reduction in total

The antihypertensive effects have been attributed to vasodilation following the direct activation of the nitric oxide/guanylate cyclase pathway as well as stimulation of muscarinic receptors and/or the cyclooxygenase pathway which would be caused by phenolic compounds and flavonoids [96]; inhibition of lipid peroxidation, upregulation of antioxidant status, and improved insulin sensitivity [97]; a decreased cardiac beating frequency [98]; and/or a (potas-

The papaya plant *C. papaya* probably has its origin in Mexico and the northern parts of South America and has subsequently become naturalized throughout other tropical and subtropical regions. Various cultivars are grown for their edible ripe fruits which are usually consumed raw. The juice from ripe papayas is a popular low-calorie beverage and is also added as a flavoring in candies, jellies, and ice cream; the unripe fruit is incorporated in various dishes; the young leaves and flower buds may be consumed as vegetables; and the ground black seeds

The relatively high amount of the protease papain in unripe fruits has been taken advantage of for centuries by the indigenous peoples of the Americans and Caribbean to tenderize meat [101]. Based on this practice, papain is now included as a component in some powdered meat tenderizers [102]. A few other important contemporary uses of papain are its medical use against dyspepsia and other digestive disorders and disturbances of the gastrointestinal tract

Preparations from papaya leaves are traditionally used for treating a wide variety of diseases ranging from dengue fever and malaria to diabetes mellitus, hypercholesterolemia, and

flavonoids, triterpenes, saponins, steroids, alkaloids, and/or fatty acids [94].

serum cholesterol in women with stage one hypertension [100].

sium-sparing) diuretic activity [99].

**3.6. Caricaceae –** *Carica papaya* **L.**

are sometimes used as a substitute for black pepper.

[103], and its addition to beer as a clarifying agent [104].

**Figure 4.** Apiaceae – *Apium graveolens* L. (from: https://goo.gl/images/7RWqQ4).

Nevertheless, *A. graveolens* is extensively used in traditional medicinal systems – including those in Suriname-against numerous diseases ranging from respiratory ailments and liver diseases to menstrual problems and hypertension [45, 81, 82].

Support for an antihypertensive effect of preparations from *A. graveolens* came from the decreased blood pressure and heart rate in salt-induced hypertensive rats, normotensive rats, and normotensive rabbits following intraperitoneal administration of extracts from seeds, stalks, or roots of the plant [83–86]. The results from studies with isolated rat aortic rings suggested that these effects occurred through vasodilation [83] or the stimulation of muscarinic receptors [84]. However, extracts from celery leaves, stalks, and roots have also been reported to stimulate diuresis in several experimental models [87, 88], providing an alternative explanation for their blood pressure-lowering effects.

The antihypertensive effects of *A. graveolens* have been attributed to the presence in the plant of the benzofuran 3-n-butylphthalide [86, 89] that, along with sedanolide, is also primarily responsible for the aroma and taste of celery. Clinical studies indeed showed a reduction in blood pressure of patients who had been given celery juice [90, 91]. These and other clinical data first led to the approval in China of 3-n-butylphthalide for the treatment of cerebral ischemia, and the preparation of clinical studies to assess n-butylphthalide formulated as softgel capsules for its safety in patients with mild to moderate acute ischemic stroke [92].

#### **3.5. Arecaceae –** *Cocos nucifera* **L.**

The coconut tree *C. nucifera* is believed to originate from the South East Asian peninsular region. It has probably spread to many other parts of the world by sea-faring traders and through marine currents, and is now cultivated in many subtropical and tropical countries. Refrigerated coconut water or coconut juice is a much appreciated refreshing drink all over the world; the fleshy coconut 'meat' is used fresh or dried in confections and desserts; coconut milk is frequently added to curries and other spicy dishes; and coconut oil is used for frying and preparing margarine and in various cosmetics [93].

Almost all parts of *C. nucifera* have long been used in traditional medicine for treating many disease conditions, among others, diarrhea, fever and malaria, renal diseases, asthma, diabetes mellitus, hair loss, menstrual disorders, venereal diseases, as an oral contraceptive, and against hypertension [45, 94]. Pharmacological studies with extracts, fractions, and isolated compounds from parts of *C. nucifera* indeed showed a variety of activities ranging from antimicrobial and antiparasitic activities to vasodilatory and antihypertensive effects [95]. Some of these observations may be related to the presence in the plant of polyphenols, tannins, flavonoids, triterpenes, saponins, steroids, alkaloids, and/or fatty acids [94].

Evidence for an antihypertensive activity from *C. nucifera* came from the relaxation of isolated rat aortic rings by an ethanolic extract of *C. nucifera* endocarp and the reduced blood pressure in salt-induced hypertensive rats treated with this preparation [96]; the decreased blood pressure in a rat model of insulin resistance and acquired systolic hypertension following administration of tender coconut water [97]; and the decrease in heart rate of hypertensive Wistar rats which were given coconut water [98]. Notably, in a small clinical study, coconut water given for 2 weeks reportedly lowered the blood pressure in 71% of hypertensive individuals [99], while the fresh vascular sap from the immature, unopened inflorescence given once per day for 5 consecutive weeks led to a decrease in blood pressure as well as a reduction in total serum cholesterol in women with stage one hypertension [100].

The antihypertensive effects have been attributed to vasodilation following the direct activation of the nitric oxide/guanylate cyclase pathway as well as stimulation of muscarinic receptors and/or the cyclooxygenase pathway which would be caused by phenolic compounds and flavonoids [96]; inhibition of lipid peroxidation, upregulation of antioxidant status, and improved insulin sensitivity [97]; a decreased cardiac beating frequency [98]; and/or a (potassium-sparing) diuretic activity [99].
