1.1 BACKGROUNG OF STUDY
This is a genus of the family Euphorbiaceae. It was first identified in Central and Southern India in 18th century. It is called carry me seed, stone-breaker, wind breaker, gulf leaf flower or gala of wind, (Bharatiya 1992).
There are over 300 genera with over 5,000 species in the Euphorbiaceae world wide. The Phyllantus is one of the genus that falls under this enormous family. Phyllantus has about 750-800 species, found in tropical and subtropical regions. Green medicine is safe and more dependable than the costly synthetic drugs, many of which have adverse side effects (Joseph and Raj, 2010). The use of medicinal plants by man for the treatment of diseases has been in practice for a very long time. Screening of compounds obtained from plants for their pharmacological activity has resulted in the isolation of innumerable therapeutic agents.
Over 50% of all modern chemical drugs are of natural plant product origin and is essential in drug development programs of the pharmaceutical industry (Burton et. al 1983).
1.1.2 Phyllantus amarus (P. amarus)
P. amarus is an erect annual herb of not more than one and half feet tall and has small leaves and yellow flowers. It is a broad medicinal plant that has received world-wide recognition (Srividiya and Perival, 1995).
In herbal medicine, P. amarus has reportedly been used to treat jaundice, diabetes, otitis, diarrhea, swelling, skin ulcer, gastrointestinal disturbances and blocks DNA polymerase in the case of hepatitis B virus during reproduction, (Oluwafemi, and Debiri, 2008).
In Nigeria, it is called “Oyomokeisoamankedem” in Efik, “Iyin Olobe” in Yoruba and “Ebebenizo” in Bini (Etta, 2008). In traditional medicine, it is used for its hepatoprotective, anti-diabetic, antihypertensive, analgesic, anti-inflammatory and anti- microbial properties (Adeneye et al; 2006). The plant is also used in the treatment of stomach disorders, skin diseases and cold (Kokwaro, 1976; Iwu, 1993). It has anti-diarrhoea effect (Odetola and Akojenu, 2000). Its anti-viral activity against hepatitis B virus has been established (Thyagarajan et al; 1988, Wang et al; 1995), anti- carcinogenic (Joy and Kuttan, 1998), anti mutagenic activities (Joy and Kuttan, 1998), antiplasmodial (Soh et al. 2009).
Plants contain numerous constituents, some tend to possess some level of toxicity. Cases of this toxicity in plants have been reported (Santox et al; 1995, Shaw et al; 1997, Kaplowitz, 1997). P. amarus has been classified among plants with a low potential for toxicity, with an LD50 averaging 2000mg/kg 1day (Krithika and Verma, 2009).