Antioxidant Activity of Ethanolic Extract from Tandui Leaves (Mangifera rufocostata Kosterm.) by DPPH Radical Scavenging Method

Free radicals are atoms or molecules that have one or more unpaired electrons on their outer orbital, highly reactive. Increase the formation of free radicals (Phaniendra et al., 2015). Oxidative stress conditions would increase the formation of free radicals (Lobo et al., 2010). Highly reactive free radicals and oxygen species can initiate degenerative diseases such as cancer, diabetes, hypertension, atherosclerosis, and neurodegenerative disorders (Liguori et al., 2018). Antioxidants, molecules with a radical-scavenging capacity, are thought to exert a protective effect against free radical damage (Lee et al., 2017). In recent years, there has been an increasing interest in finding natural antioxidants, which can protect the human body from free radicals and retarded the progress of many chronic diseases (Yashin et al., 2017). Genus of Mangifera has been reported as an antioxidant activity with the DPPH scavenging method (Ramirez et al., 2014; Sultana et al., 2012). The members of the Mangifera genus are used as food or traditional herbal medicine. Several members of Mangifera plants also have been used as an antioxidant, both traditionally used in the community and separated by the fractionation method to obtain the fraction with the highest antioxidant activity (Lukmandaru et al., 2012; Sutomo et al., 2014). One of the medicinal plants from this genus was tandui (Mangifera rufocostata Kosterm.). This plant was grown in South Kalimantan, Indonesia. Preliminary studies show that leaves of tandui contain tannins, phenolics, flavonoids, and steroidal saponins. Flavonoid and phenolic compounds may be useful as antioxidants from natural sources (Tungmunnithum et al., 2018). However, the antioxidant activity of tandui has not yet been Antioxidant Activity of Ethanolic Extract from Tandui Leaves (Mangifera rufocostata Kosterm.) by DPPH Radical Scavenging Method


INTRODUCTION
Free radicals are atoms or molecules that have one or more unpaired electrons on their outer orbital, highly reactive. Increase the formation of free radicals (Phaniendra et al., 2015). Oxidative stress conditions would increase the formation of free radicals (Lobo et al., 2010). Highly reactive free radicals and oxygen species can initiate degenerative diseases such as cancer, diabetes, hypertension, atherosclerosis, and neurodegenerative disorders (Liguori et al., 2018).
Antioxidants, molecules with a radical-scavenging capacity, are thought to exert a protective effect against free radical damage (Lee et al., 2017). In recent years, there has been an increasing interest in finding natural antioxidants, which can protect the human body from free radicals and retarded the progress of many chronic diseases (Yashin et al., 2017).
Genus of Mangifera has been reported as an antioxidant activity with the DPPH scavenging method (Ramirez et al., 2014;Sultana et al., 2012). The members of the Mangifera genus are used as food or traditional herbal medicine. Several members of Mangifera plants also have been used as an antioxidant, both traditionally used in the community and separated by the fractionation method to obtain the fraction with the highest antioxidant activity (Lukmandaru et al., 2012;Sutomo et al., 2014).

Extraction
The leaves of tandui dried in room temperature and ground into powder. As much as 200 g of leaf powder was extracted with ethanol. The liquid extracts were filtered with filter paper. The filtrates were evaporated with a rotary evaporator to remove the solvent and get crude extracts as much as 35.14 g with a yield of 17.57%.

Phytochemical screening
A small portion of the dry extract was used for the phytochemical tests for compounds, which include tannins, flavonoids, and steroids following the methods (Tiwari et al., 2011;Nugrahani et al., 2016)

DPPH radical scavenging assay
The samples with different concentrations of plant extracts (10-50 μg/ml) were reacted with the stable DPPH radical in methanol solution. The reaction mixture consisted of adding 2 ml of sample and 2 ml of DPPH (0.4 mM) in methanol solution. The mixture was gently homogenized, and after 30 minutes incubation in dark condition at room temperature (Molyneux, 2004 (Bakti et al., 2017).

RESULTS AND DISCUSSION
The extracts of tandui leaves were further investigated to determine phytochemical compounds in the extract. The typical phytochemistry content from the ethanol extract of tandui, such as flavonoids, phenols, tannins, and saponins have been identified as presented in Table I.
Tannins and flavonoids is one of polyphenol that can donate hydrogen and act as an antioxidant. While saponins are a group of compounds commonly found in the genus Mangifera (Shah et al., 2010).  (Elkhamlichi et al., 2017). In the present study, the percentage of scavenging effect on the DPPH radical was concomitantly increased with the increase in the concentration of leave of ethanolic extracts for 10 to 50 µg/ml. The DPPH radical scavenging activity is given in Table II.
Quercetin, as a well known potent antioxidant, was used as a positive control for DPPH scavenging activity.
Leaves of tandui showed the highest ability in DPPH scavenging activity, which measured by the lowest IC50 These results indicate that the ethanol extract of tandui leaves has strong antioxidant activity (Mustarichie, 2017).