Effects of Fermentation Time and Extraction Solvent on Antioxidant Activity and Total Phenolic and Flavonoid Content of Phenolic Extract from Orange (Citrus reticulata) Peel

Khalilan Lambangsari; Agnesia Gita Regita; Laely Munawaroh; Elen Etha Yulinar Simanjuntak; Nadia Delfi Zafira; Muhammad Yusuf Abduh

doi:10.31436/iiumej.v26i1.3173

Authors

Khalilan Lambangsari Bandung Institute of Technology https://orcid.org/0000-0002-3377-0592
Agnesia Gita Regita Bandung Institute of Technology
Laely Munawaroh Bandung Institute of Technology
Elen Etha Yulinar Simanjuntak Bandung Institute of Technology
Nadia Delfi Zafira Bandung Institute of Technology
Muhammad Yusuf Abduh Bandung Institute of Technology https://orcid.org/0000-0002-9619-6014

DOI:

https://doi.org/10.31436/iiumej.v26i1.3173

Keywords:

Antioxidant activity, Aspergillus niger, Solid state fermentation, Hesperidin, Orange Peel

Abstract

The rise in consumption of oranges worldwide causes an increase in orange peel, which accounts for 30 – 35% of the orange’s weight. Phenolic compounds found in orange peel are conjugated with the cell wall components. The utilization of solid-state fermentation by Aspergillus niger can release bound phenolic compounds from the cell wall, thereby hence increases phenolic compounds extraction. This study aims to determine the effects of the fermentation time of orange peel using A. niger and extraction solvents (methanol, ethanol, acetone) on the yield of orange peel extract, total phenolic content, total flavonoid content, antioxidant activity, and hesperidin content of orange peel extract. The results showed that all the parameters performed best after 3 days of fermentation. The extract yield, total phenolic content, and total flavonoid content were 34.1% (dry weight), 51.01 mg GAE/g extract, and 14.75 mg QE/g extract, respectively. Moreover, the highest antioxidant activity (IC₅₀ value) and hesperidin content found in orange peel were 184.32 ppm and 27.47 mg/g (dry weight) using 80% ethanol. Furthermore, the utilization of deep eutectic solvent as a biodegradable and environmentally benign substitute for organic solvents was investigated, proving that the alternative mixture of choline chloride and ethylene glycol is competitive.

ABSTRAK: Peningkatan penggunaan oren di seluruh dunia menyebabkan peningkatan sisa dalam bentuk kulit oren, iaitu 30 – 35% daripada beratnya. Sebatian fenolik yang terdapat dalam kulit oren berkonjugasi dengan komponen dinding sel. Penggunaan penapaian keadaan pepejal oleh Aspergillus niger boleh membebaskan sebatian fenolik terikat dari dinding sel dan seterusnya meningkatkan hasil pengekstrakan sebatian fenolik. Kajian ini bertujuan untuk mengetahui pengaruh variasi dalam masa penapaian dan pemilihan pelarut terhadap hasil ekstrak kulit oren, jumlah kandungan fenolik, jumlah kandungan flavonoid, aktiviti antioksidan, dan kandungan hesperidin ekstrak kulit oren. Hasil menunjukkan bahawa selepas 3 hari penapaian semua parameter menunjukkan prestasi terbaik. Hasil ekstrak, jumlah kandungan fenolik dan jumlah kandungan flavonoid masing-masing adalah 34.1% (berat kering), 51.01 mg ekstrak GAE/g dan 14.75 mg ekstrak QE/g. Selain itu, aktiviti antioksidan tertinggi (nilai IC₅₀) dan kandungan hesperidin yang terdapat dalam kulit oren ialah 184.32 ppm dan 27.47 mg/g menggunakan 80% etanol. Tambahan pula, penggunaan deep eutectic solvent sebagai plearut yang mesra alam dan dapat terdegradasi telah dikenalpasti dan terbukti bahawa campuran alternatif kolin klorida dan etilena glikol adalah kompetitif.

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