Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative

A number of tropical fruit peel has been known to possess high antioxidant activity,however, antioxidant data on the Malaysian tropical fruit peel is still lacking. In this study, red rambutan (Nephelium lappaceum) peel were reported to possess high antioxidant activities in comparison with peels ob...

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Main Author: Sia, Winne Chiaw Mei
Format: Thesis
Language:English
Published: 2015
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Online Access:http://psasir.upm.edu.my/id/eprint/64822/1/FPSK%28m%29%202015%2053IR.pdf
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spelling my-upm-ir.648222018-07-25T01:21:52Z Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative 2015-10 Sia, Winne Chiaw Mei A number of tropical fruit peel has been known to possess high antioxidant activity,however, antioxidant data on the Malaysian tropical fruit peel is still lacking. In this study, red rambutan (Nephelium lappaceum) peel were reported to possess high antioxidant activities in comparison with peels obtained from tropical fruits, namely mangosteen (Garcinia mangostana), “langsat” (Lansium domesticum), Sapodilla (Manilkara zapota), passion fruit (Passiflora edulis), soursop (Annona muricata), and mango (Mangifera indica). The extraction method of rambutan peel was determined by using single factor experiments. Results showed that rambutan peel had the lowest EC50 (9.30±0.35 mg/g) and the highest TPC (359.60±20.85 GAE mg/g). Thus, rambutan peel was selected for further investigation on different extraction time (1 to 5 hours) and extraction temperature (25-60ºC). The extraction conditions of the red rambutan were determined to be 80% ethanol for 2 hours at 50ºC. The crude extract of the rambutan’s peel showed EC50 of 6.39±0.32 mg/g (DPPH), 333.70±13.35 mg/g (ABTS), 676.96±12.93 trolox equivalents mg/g (FRAP), 269.70±15.90 GAE mg/g (TPC) and 88.67±0.14% antioxidant activity (as measured by BCB). The crude extract of rambutan peel was then fractionated into three sub-fractions by using silica-packed column chromatography. Results reported the presence of phenolic compounds such as geraniin,ellagic acid and gallic acid. In the last part of this study, the crude extracts and the subfraction (SF II) reported with the highest antioxidant activity were supplemented into sunflower oil to study their effects in delaying lipid oxidation under accelerated conditions. Rambutan extract is a potential source of antioxidant. The oxidative activities of the crude extracts and sub-fraction (SF II) at all concentrations were significantly (p <0.05) higher than the control. Results reported that with two years storage period at ambient temperature, the sub-fraction, (SF II) at 300ppm, was observed to work more effectively than the synthetic antioxidant, t-tocopherol. SF II possessed a protective effect comparable with Butylated Hydroxyanisole (BHA). Therefore, rambutan extract could be used as a potential alternative source of antioxidant in the oil industry or other fat-based products to delay lipid oxidation. Antioxidants Chemistry Techniques - Analytical - Fruit 2015-10 Thesis http://psasir.upm.edu.my/id/eprint/64822/ http://psasir.upm.edu.my/id/eprint/64822/1/FPSK%28m%29%202015%2053IR.pdf text en public masters Universiti Putra Malaysia Antioxidants Chemistry Techniques - Analytical - Fruit
institution Universiti Putra Malaysia
collection PSAS Institutional Repository
language English
topic Antioxidants
Chemistry
Techniques - Analytical - Fruit
spellingShingle Antioxidants
Chemistry
Techniques - Analytical - Fruit
Sia, Winne Chiaw Mei
Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative
description A number of tropical fruit peel has been known to possess high antioxidant activity,however, antioxidant data on the Malaysian tropical fruit peel is still lacking. In this study, red rambutan (Nephelium lappaceum) peel were reported to possess high antioxidant activities in comparison with peels obtained from tropical fruits, namely mangosteen (Garcinia mangostana), “langsat” (Lansium domesticum), Sapodilla (Manilkara zapota), passion fruit (Passiflora edulis), soursop (Annona muricata), and mango (Mangifera indica). The extraction method of rambutan peel was determined by using single factor experiments. Results showed that rambutan peel had the lowest EC50 (9.30±0.35 mg/g) and the highest TPC (359.60±20.85 GAE mg/g). Thus, rambutan peel was selected for further investigation on different extraction time (1 to 5 hours) and extraction temperature (25-60ºC). The extraction conditions of the red rambutan were determined to be 80% ethanol for 2 hours at 50ºC. The crude extract of the rambutan’s peel showed EC50 of 6.39±0.32 mg/g (DPPH), 333.70±13.35 mg/g (ABTS), 676.96±12.93 trolox equivalents mg/g (FRAP), 269.70±15.90 GAE mg/g (TPC) and 88.67±0.14% antioxidant activity (as measured by BCB). The crude extract of rambutan peel was then fractionated into three sub-fractions by using silica-packed column chromatography. Results reported the presence of phenolic compounds such as geraniin,ellagic acid and gallic acid. In the last part of this study, the crude extracts and the subfraction (SF II) reported with the highest antioxidant activity were supplemented into sunflower oil to study their effects in delaying lipid oxidation under accelerated conditions. Rambutan extract is a potential source of antioxidant. The oxidative activities of the crude extracts and sub-fraction (SF II) at all concentrations were significantly (p <0.05) higher than the control. Results reported that with two years storage period at ambient temperature, the sub-fraction, (SF II) at 300ppm, was observed to work more effectively than the synthetic antioxidant, t-tocopherol. SF II possessed a protective effect comparable with Butylated Hydroxyanisole (BHA). Therefore, rambutan extract could be used as a potential alternative source of antioxidant in the oil industry or other fat-based products to delay lipid oxidation.
format Thesis
qualification_level Master's degree
author Sia, Winne Chiaw Mei
author_facet Sia, Winne Chiaw Mei
author_sort Sia, Winne Chiaw Mei
title Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative
title_short Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative
title_full Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative
title_fullStr Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative
title_full_unstemmed Antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative
title_sort antioxidant properties of rambutan peel extract and sub-fractions and their potential as vegetable oil preservative
granting_institution Universiti Putra Malaysia
publishDate 2015
url http://psasir.upm.edu.my/id/eprint/64822/1/FPSK%28m%29%202015%2053IR.pdf
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