Background: Rambutan is tropical fruit consumed either in fresh or processed fruit.The direct consumption or processing of rambutan fruit resulted in high amount of waste from peel and seed, therefore, it is necessary to take benefit from rambutan peel to be used as food supplement via antioxidant properties.Objective: This study is intended to evaluate the antiradical activities of methanolic extract and its fraction of rambutan peel from two cultivars (Aceh and Binjai) and to correlate the antiradical activities with phenolics and flavonoid contents.Methodology: The rambutan peel from two cultivar (Aceh and Binjai) is dried, macerated with methanol, evaporated and added with water.The methanolic extract is fractionated with petroleum ether, chloroform and ethyl acetate to get the corresponding fraction.Methanolic extract and its fraction are then subjected to antiradical activity measurement using synthetic DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical, phenolics determination and flavonoid determination.Results: The methanolic extract and its fraction,either cultivar Aceh or Binjai,revealed the high antiradical activities with similar.Ethyl acetate fraction exhibited the strongest antiradical activities among samples evaluated with IC 50 values of 2.66 µg mLG 1 (cultivar Aceh) and 2.62 µg mLG 1 (cultivar Binjai).Ethyl acetate fraction also exhibited the strongest phenolics and flavonoid contents accounting of 37.72±4.52g Gallic Acid Equivalent (GAE)/100 (Aceh) and 32.40±2.37g GAE/100 g (Binjai).The correlation between antiradical activities with phenolics and flavonoids contents showed with correlation, each with R 2 value of 0.0271 (phenolics) and 0.1122 (flavonoids).Conclusion: The methanolic extract and its fraction of rambutan peel cultivar Aceh and Binjai revealed strong DPPH antiradical activities therefore, rambutan peel can be exploited as natural antioxidant sources and is potential to be used as functional food.
Free radical is any molecular species that have unpaired free electrons in their outer orbital shell that make radicals highly reactive, resulting in pathogenesis conditions such as cellular injury, premature aging, cancer, hepatic disorders, neurodegenerative diseases, cardiovascular disease, and kidney disease. One source of natural antioxidant is jackfruit. The purpose of this research was to determine the phenolic and flavonoid contents in the extracts and fractions of jackfruit peel and their potential as antioxidants. Jackfruit peel powder was extracted from maceration. The total phenolic content was determined by the Folin-Ciocalteu method. Meanwhile, flavonoid content was determined using the aluminium chloride complex colorimetric method. Measurements of antioxidant activity were conducted using the 2,2-diphenyl-1-picrylhydrazyl (DPPH). The ethyl acetate fraction had high phenolic and flavonoid contents, which were 49.667±1.508 g GAE/100 g of sample and 70.199±0.374 g of quercertin equivalent/100 g. The ethyl acetate fraction had the strongest antioxidant activity with IC50 value of 4.539±0.201 µg/ mL and correlation value (R2 ) of 0.5881 for phenols and R2 of 0.7241 for flavonoids. Ethyl acetate fraction of jackfruit peel is very potential to be developed as a natural antioxidant and functional food.
Kulit rambutan (Nephelium lappaceum L.) karena konsumsi buah rambutan segar diperhitungkan sebagai limbah, oleh karena itu eksplorasi kulit rambutan sebagai antioksidan alami sangat dibutuhkan. Tujuan penelitian ini adalah untuk mengetahui aktivitas antioksidan kulit rambutan dari kultivar Aceh dengan menggunakan uji radikal DPPH, uji radikal ABTS, uji kemampuan reduksi besi (FRAP) dan uji chelating logam, untuk berkorelasi dengan jumlah fenolat dan flavonoid dan struktur penyuluhan.
Kulit rambutan bubuk diekstraksi dengan teknik maserasi menggunakan metanol sebagai pelarut ekstraksi. Ekstrak metanol diperoleh dengan air hangat dan difraksinasi menggunakan petroleum eter, kloroform dan etil asetat untuk mendapatkan fraksi yang sesuai. Kultivar Rambutan Aceh mengungkapkan aktivitas antiradik ABTS yang lebih tinggi. Selanjutnya, di antara ekstrak metanol dan fraksinya, fraksi etil asetat menunjukkan aktivitas antiradik tertinggi dengan menggunakan nilai DPPH dengan nilai IC50 3,34 mikrogram per mililiter, radikal ABTS dengan nilai IC50 3,10 mikrogram per mililiter. Fraksi etil asetat juga menunjukkan nilai FRAP tertinggi 1424,89 plus minus 28,56 mikrogram per mililiter. Fraksi etil asetat juga mengungkapkan aktivitas pengkelatan logam tertinggi, terhitung 12,32 persen. Aktivitas ini berkorelasi dengan kandungan fenolat dan flavonoid. Kulit Rambutan menunjukkan aktivitas antioksidan yang kuat, mengandung sejumlah besar fenolat dan flavonoid dan berpotensi untuk dikembangkan sebagai makanan fungsional. Identifikasi senyawa aktif menggunakan spektroskopi (FTIR, LC-MS, GC-MS dan NMR) menghasilkan formula kimia dari kulit rambutan dari kultivar adalah C11H12O6 (2-hidroksi-3-oxobutan-2-yl 3.4-dihidroksibenzoat).
Rambutan (Nephelium lappaceum L.) peel due to consumption of fresh rambutan fruit is taken into account as waste, therefore the exploration of rambutan peel as natural antioxidant is highly needed. The aim of this study is to investigate the antioxidant activity of rambutan peel from cultivar Aceh using DPPH radical assay, ABTS radical assay, ferric reducing activity power (FRAP) and metal chelating assay, to correlate with total phenolics and flavonoids and elucidation structure. The powdered rambutan peel is extracted using maceration technique using methanol as extracting solvent. The methanolic extract is added with warm water and fractionated using petroleum ether, chloroform and ethyl acetate to get corresponding fractions. Rambutan cultivar Aceh revealed the higher ABTS antiradical activity. Furthermore, among methanolic extract and its fraction, ethyl acetate fraction exhibited the highest antiradical activity using DPPH with IC50 values of 3.34 mikrogram per mililiter, ABTS radical with IC50 values of 3.10 mikrogram per mililiter. The ethyl acetate fraction also revealed the highest FRAP values of 1424.89 plus minus 28.56 mikrogram per mililiter. The ethyl acetate fraction also revealed the highest metal chelating activities, accounting of 12.32 percent. These activities are correlated with phenolics and flavonoid contents. Rambutan peel exhibited strong antioxidant activities, contained high amounts of phenolics and flavonoid and is potential to be developed as functional food. Identification of active compound using spectroscopic (FTIR, LC-MS, GC-MS and NMR) resulted the chemical formula from rambutan peel from cultivar is C11H12O6 (2-hydroxy-3-oxobutan-2-yl 3.4-dihydroxybenzoate).
Moringa oleifera is a plant that is empirically widely used as a medicine to treat hyperglycemia, anti-inflammatory, antidiabetic, antimicrobial, anticancer, antioxidant, gastric ulcer, skin disease, fever, fatigue, hysteria, thrush, bladder, and bronchitis. Moringa oleifera contains secondary metabolites such as flavonoids, tannins, terpenoids, alkaloids, and phenolics. This study aimed to investigate the antioxidant activity and levels of phenolic and flavonoids in the extracts and fractions of moringa pulp and seeds. The pulp and seeds of Moringa were extracted using the maceration method and fractionated using the liquid-liquid extraction method. Antioxidant activity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Phenolic content was measured using the Folin-Ciocalteau method. Meanwhile, the flavonoid content was determined using the AlCl3 colorimetric method with UV-Vis spectrophotometry. The ethyl acetate fraction of moringa pulp and seeds had the strongest antioxidant activity with IC50 values of 5.97 µg/mL and 5.08 µg/mL, respectively. Ethyl acetate fraction also has high phenolic and flavonoid content in the pulp and seeds of moringa with a phenolic content of 43.956 mg GAE/g sample for pulp and 9.429 mg GAE/g sample for moringa seeds. The flavonoid content of 94.257 mg QE/g sample for pulp and 93.719 mg QE/g sample, with the highest correlation between phenolic compounds and flavonoids on antioxidant activity, was obtained in moringa pulp with the highest correlation (R2 = 0.6514) for phenolic and R 2 = 0.7531) for flavonoids. In conclusion, the ethyl acetate fraction of moringa pulp and seeds can be further developed as an antioxidant and functional food.
