**1. Introduction**

Bitter melon (*Momordica charantia* L.) commonly called bitter melon, is also known as bitter gourd, bitter apple, bitter squash, balsam-pear, belongs to Cucurbitaceae family. It is a plant found in tropical and subtropical regions of Asia and Africa, where it is valued for its various health benefits. This traditional tropical plant has been claimed to have therapeutic effects for ages for its pharmacological activities, and nutritional properties due to its content of bioactive compounds.

#### **Figure 1.**

Momordica charantia: *A popular health-promoting vegetable with multifunctionality [1].*

The presence of many bioactive compounds, some of which possess potent biological actions, this plant is used in folk medicine all over the world for the treatment of different pathologies. It has been used in a wide range of medical applications, such as diabetes, cancer, hypertension, obesity, bacterial and viral infections, and even AIDS (**Figure 1**) [1, 2]. It is also used for pain relief, against chronic fever, in cases of jaundice and illnesses of the liver or the digestive system [2]. In Turkish traditional medicine the oil obtained from the ripe fruits of bitter melon, macerated in olive oil warmed by the sun, was combined with honey, and used for the prevention and healing of gastric ulcers [3]. In African folk medicine it is mainly used for worm infections, inflammation, fever, syphilis, rheumatism, and skin diseases [4].

*Momordica charantia* L. is a widely cultivated medicinal plant around the world. All parts of *M. charantia* possess important medicinal properties, including antiinflammatory, antidiabetic, anticancer, hypotensive, anti-obesity, antimicrobial, antihyperlipidemic, antioxidant, immuno-modulatory, anthelmintic, neuro-protective, as well as hepato-protective properties both in vitro and in vivo (**Figure 1**).

## **2. Nutritional value and chemical composition of** *Momordica charantia*

Bitter melon (*Momordica charantia*) is an unique bitter tasting herbaceous medicinal plant, cultivated in tropical and subtropical regions of many countries; which is one of the nature's most valueable gifts although it is one of the discarded vegetables by people, just because of its bitter taste. All parts of the plant, including the fruit, taste very bitter, mainly because of the presence of three pentacyclic triterpenes, momordicinin, momordicin and momordicilin. It contains lipids, fiber, protein, carbohydrates, calcium, sodium, potassium, iron, manganese, copper, phosphorus and vitamins. It also contains phytochemicals, vitamins, antioxidants, and bioactive chemicals. It is a plant high in health-beneficial compounds such as antioxidants, flavonoids, phytosterols, and saponins. Since antiquity, it is used in different countries as a folk medicine traditionally. It possess rich nutritive values among cucurbits and being a good source of medicinal products, it contains carbohydrates, proteins, fibers, vitamins (C, A, E, B1, B2, B3, and B9 as folate), and minerals (potassium, calcium, zinc, magnesium, phosphorous and iron) [5, 6]. Fruits are reported to contain vitamin C, A and P, thiamine,

*Bitter Melon: A Multifunctional Medicinal Plant with Powerful Bioactive Compounds DOI: http://dx.doi.org/10.5772/intechopen.98812*

riboflavin, niacin, and minerals with 93.2% of water content, while protein and lipids account for 18.02 and 0.76% of its dried weight, respectively [7, 8]. Its seeds also represent a good source of lipids, polyunsaturated fatty acids and conjugated linolenic acid [9].

Bitter melon has been associated with anti-cancer, anti-microbial, antiinflammatory and anti-diabetic properties. The medicinal values of the bitter gourd fruit are linked to its high content of phenolics, which act as antioxidants. Phenolic compounds containing phenolic acids, coumarins, lignins, tannins, lignanes and flavonoids are among the secondary metabolites that are abundant in the plant. *M. charantia* is also a good source of phenolic compounds, which can protect from oxidative damage by acting directly on reactive oxygen species and to activate endogenous defense systems [10]. The biological activity of *M. charantia* depends on its major phytochemical constituents, containing phenylpropanoids, and other bioactive compounds, such as polyphenols, phenolic acids, flavonoids, essential oils, fatty acids, amino acids, lectins, sterols and saponins, tocopherols, monoterpenes, sesquiterpenes, [11, 12], including cucurbitane-type triterpenoids, cucurbitane-type triterpene glycosides, and some proteins present in fruits, seeds, roots, leaves and vines [13]. The most prevalent chemical constituents are cucurbitane-type triterpenoids, the bitterness of *M. charantia* is the consequence of cucurbitane-type triterpenoids: cucurbitacins, momordicines I and II and triterpene glycosides: momordicosides, exhibiting a broad range of biological activities, mainly anti-inflammatory and anti-diabetic [14]. Different major constituents found in different varieties and different parts of the plants are summarized below (**Table 1**) [14, 15].

*M. charantia* is one such sample that holds rich phytochemicals and is an effective agent in dietary regimens to prevent against different maladies. Brief about the *M. charantia*, it is used as a vegetable in many countries but since time immemorial, it is also used for administration of numerous ailments comprising wide range of pharmacological activities for instance, antioxidant, anti-inflammatory,


#### **Table 1.**

*Major bioactive components of bitter melon and their related functions [15].*

antimicrobial, antidiabetic, antiobesity, antiulcer, anticancer, hypotensive, and blood cholesterol lowering effects that are demonstrated in **Figure 1** and **Table 1**. The following is an overview of its common pharmacological activities.
