**3.1 Origin and distribution**

In the tropical and subtropical regions of the earth. *Eclipta alba* is usually found on poorly drained wet areas, on the dikes of rice paddies, along streams and ditches in marshes. It is most commonly found in elevated lands with 1200 mm of rainfall or more. It grows very well in salty and humid conditions but is mostly a plantation crop [15]. In few countries, it is found near sea level and is said to be a naturalized weed in waste places, open fields often near ditches and in cultivated areas [16]. In some parts of the world, it is a common plant of foreshores, streamsides, wet situations, weed of wet pasture and in roadside ditches. In is also found in low altitudes [17].


#### **3.2 Chemical constituents**

In the year 1991, a new aldehyde was isolated from this plant. The leaves of this plant contain a-terthienyl methanol, 2-formyl-terthienyl, stigmasterol, de-me-wedelolactone 7-O-glucosides and wedelolactone [18]. Aerial parts of the plant contain β-amyrin, wedelolactone, phytosterol A, luteolin-7-glucoside and its glucosides [19].

#### **3.3 Pharmacology**

In Ayurveda and in traditional Chinese herbal medicine, this species is widely used. It is used as liver tonic, rejuvenative and also widely used for better growth of hair [20]. The whole plant is used as ophthalmic, purgative, astringent, deobstruent, depurative, emetic, febrifuge, tonic and styptic. It is used internally for the treatment of anemia and diphtheria, dropsy and liver complaints [21], tinnitus, premature greying of the hair and tooth loss. It is also widely used for many external applications like oil for hair loss, dermatitis, wounds and even for athlete's foot [22]. For treating scorpion stings, its leaves are used. The plant juice is widely used for catarrhal problems and for those having increased production of bilirubin.

At the time of flowering, this plant is mostly harvested and is dried for further use. The roots are purgative and emetic. In cattle, it act as antiseptic to cure ulcers and wounds. In Ayurvedic medicine, the leaves of this plant are used a liver tonic. The dye produced from *E. alba* is most widely used for the purpose of tattooing [23].

To treat eczema and dermatitis, *E. alba* is widely used. In China and Brazil, it is also used as antivenom against snakebite. To reduce the inflammation of spleen and liver on few occasions, *E. alba* was used and found to be effective. Antiviral activity particularly in inhibiting Ranikhet disease virus, the alcoholic extract of the plant was proved to be very effective. To promote bile flow and protect the parenchyma, it is commonly used in viral hepatitis. This plant was widely used for antiaging too. In case of debility, the tonic obtained particularly from *Eclipta alba* is used. For minor cuts, burns and for inflammation, it is used externally. In children with upper respiratory, eye and ear infection, the leaf juice is mixed with honey. In the treatment of cirrhosis of the liver and infectious hepatitis, *E. alba* is used in the phytopharmaceutical formulations of medicines [24]. For rattlesnake bite, wedelolactone obtained from this plant is used. The shoot extract shows antimicrobial activity against Gram-positive bacteria *Staphylococcus aureus* and Gram-negative bacteria *Escherichia coli*.

#### **3.4 Antiviral activity of** *Eclipta alba*

Against many viruses, the extracts of *Eclipta alba* were proved to have strong antiviral activity [25]. Though the fresh juice of leaves is used for various benefits

**59**

*Antiviral Plant Extracts*

**4.** *Phyllanthus amarus*

**4.1 Origin and distribution**

India [22]. Taxonomy

Floral formula

**4.3 Pharmacology**

Br, Ebrl, p[5], A5 G[3]

**4.2 Chemical constituents**

*DOI: http://dx.doi.org/10.5772/intechopen.85126*

the flower are found under the leaf [27].

Kingdom - Plantae Division - Angiospermae Class - Dicotyledoneae Order - Tubiflorae Family - Euphorbiaceae Genus - *Phyllanthus* Species - *amarus*

Binomial name - *Phyllanthus amarus*

like increasing appetite, mild bowel regulator, it is mainly used in viruses causing blood borne hepatitis. It is also used to protect the parenchyma and to promote bile flow which is popularly used to enhance learning and memory. In most parts of the subcontinent, it is used for jaundice, as a deobstruent and cholagogue in hepatic injury and other ailments of liver. One of the most potent inhibitory activity against HIV-1 integrase [HIV-1 IN] was found in the water extract of *Eclipta prostrate* [26].

In Ayurveda, *Phyllanthus amarus* is an Indian herb that has been used in support liver. 'Phyllanthus' is also represented by the name "leaf and flower" as the fruit and

In all tropical regions of the planet, *P. amarus* is widely distributed. The exact geographic origin of this plant was not found by Paleobotanical studies [28, 29]. This plant may be indigenous to the tropical Americas and also to the Philippines or

Some of the secondary metabolites that are present in *P. amarus* include lignins alkaloids, hydrolysable tannins, flavanoids, and polyphenols. Such phytochemicals and their structure were usually determined by using IR, UV, NMR and mass spectroscopy [30]. Apart from that, preparative thin layer chromatography and column chromatography are also used by which few new alkaloids were isolated [31].

Parts of this plant *P. amarus*, mostly fresh and occasionally dry are sold and the decoctions are used widely for herbal baths. To treat bladder and kidney disorders, herbal decoction of this plant is used in traditional medicine [32]. This herb can also be used as tonic and can also be used as an appetizer. *P. amarus* plant extracts is also used as blood purifiers. It also helps to release phlegm for light malaria fevers and anemia [33]. In combination with many other herbs, this herb is used for curing flu, asthma and fever. The leaves are boiled and used to treat dysentery and even skin disorders [34]. For constipation also, studies have proved that extracts are very effective. Apart from that, extracts have even shown anti-

cancer properties. It also has beneficial effects on liver functions.

*Antiviral Plant Extracts DOI: http://dx.doi.org/10.5772/intechopen.85126*

like increasing appetite, mild bowel regulator, it is mainly used in viruses causing blood borne hepatitis. It is also used to protect the parenchyma and to promote bile flow which is popularly used to enhance learning and memory. In most parts of the subcontinent, it is used for jaundice, as a deobstruent and cholagogue in hepatic injury and other ailments of liver. One of the most potent inhibitory activity against HIV-1 integrase [HIV-1 IN] was found in the water extract of *Eclipta prostrate* [26].
