1.1 BACKGROUND OF RESEARCH
Piper L. genus plants from Piperaceae family are well studied and
economically important for human health. There are 1200 species of Piper
distributed in the pantropical and Neotropical region in the world with more
than 400 species have been recorded in Malaysia region alone (Rahman et al.,
2016). Piper sarmentosum and Piper nigrum are the plants which play
an important role as the medicinal plant in Malaysia.
P. sarmentosum is a wild growing plant in the tropical forests and mostly in Asia
region. The leaves are simple, alternate and heart-shaped. The young leaves
consist of waxy surface and light green in colour. On the other hand, P. nigrum is a woody perennial climbing vine
that grows in the tropical area which leaves and fruit producing fragrance and
essential oil. The plant leaves are simple, alternate, oval-shaped and leathery
in texture. The upper leaves surface is dark green and whitish-green on the
Both of the plant leaves
have medicinal values which are traditionally used to treat various diseases.
According to Rahman et al., (2016) and Nahak et al., (2011), these plants were
claimed to possess anti-inflammatory, antioxidant, antimicrobial and anticancer
properties. Besides that, these species are also sharing similar values such as
antioxidant properties that can reduce free radicals in human body.
Antioxidants or inhibitors of oxidation are the substances that are able
to reduce the free radicals chain reaction and oxidation process. Free radicals
or oxidants are the molecules which have high reactivity, short half-life and
damaging the macromolecule such as DNA, protein and lipids. The imbalance
amount of free radicals leads to various effect to human body such as cancer,
aging, rheumatoid arthritis and ischemia (Patel et al., 2013). Plants are the primary natural sources of
antioxidants which beneficial to human health. Therefore, this research will
focus on the identification of antioxidant level in leave samples of P. sarmentosum and P. nigrum extracts of different solvents.
1.2 RESEARCH OBJECTIVE
To extract Piper sarmentosum and Piper
nigrum by using ethanolic and aqueous extraction.
To analyze the antioxidant
properties of P. sarmentosum and P. nigrum by using DPPH assay.
1.3 RESEARCH HYPOTHESIS
There are different level of antioxidant content in Piper sarmentosum and Piper
nigrum by using different extraction solvents.