Jurnal Biodjati 4(2):194-203, November 2019 http://journal.uinsgd.ac.id/index.php/biodjati e-ISSN : 2541-4208 p-ISSN : 2548-1606 EFFECT OF PECTIN BIODEGRADATION WITH Aspergillus niger ON TOTAL FLAVONOID CONTENT OF Citrus limon L. Muhammad Yusuf Abduh* 1 , Wahyu Zuliansyah 2 , Lestari Aprina 3 , Natalie Arazella 4 INTRODUCTION Lemon (Citrus limon L.) is a hybrid between other Citrus species from the same genus such as C. aurantifolia, C. maxima, C. medica and C. aurantium. Lemon can grow in almost all parts of the world, both tropical, subtropical, and temperate regions. The popu- larity of lemon is relatively high and continue to grow in the community because lemon has been used in various applications such as food and beverages as well as cosmetics. According to Morey (2007), the consumption of Citrus fruits in Indonesia increased from 2.83 kg per capita in 1998 to 3.39 kg per capita in 2003. As a result, around 100.000 to 200.000 tons of Citation Abduh, M. Y., Zuliansyah, W., Aprina, L. & Arazella, N. (2019). Effect of Pectin Biodegradation with Aspergillus niger on Total Flavonoid Content of Citrus limon L.. Jurnal Biodjati, 4(2), 194- 203 Received : April 19, 2019 Accepted : September 17, 2019 Abstract. Lemon peel and leaf as well as lower grade of lemon con- tain a considerable amount of flavonoid which can be extracted to produce valuable products. The presence of pectin in lemon hinders the extraction of flavonoid compound. This research was conducted to examine the effect of pectin biodegradation of lemon leaf, peel, and lower grade fruit using solid-state fermentation towards the yield of pectin, crude flavonoid, and total flavonoid content. Fermentation was carried out with the help of Aspergillus niger at 30℃ for 3, 5, 7, and 9 days of cultivation time. Pectin was extracted from the fermen- tation broth using citric acid. Crude flavonoid was extracted using maceration and stirred about 500 rpm at 50℃ for 40 minutes. Total flavonoid content was analyzed using a spectrophotometer. The op- timum cultivation time of Aspergillus niger with leaf and peel was 9 days with a pectin yield from lemon leaf was 0.43% dry weight and the pectin yield from lemon peel was 0.04% dry weight. As for the lower grade fruit, a cultivation time for 7 days showed an optimal result with a pectin yield of 0.08% dry weight. The total flavonoid content in the leaf increased up to 94.3% (1.06 mg of the quercetin equiva- lents per g of substrate) whereas the total flavonoid content in the peel and lower grade fruit increased up to 42% (0.12 mg of the quercetin equivalents per g of substrate) and 48% (0.021 mg of the querce- tin equivalents per g of substrate), respectively. These results high- lighted the potential valorization of Citrus limon L. as an alternative source for producing flavonoid in food and pharmaceutical industry. Keywords: Aspergillus niger, flavonoid, lemon, pectin, solid-state fer- mentation DOI: 10.15575/biodjati.v4i2.4537 1,2,3,4 Department of Bioengineering, School of Life Sciences and Technolo- gy Institut Teknologi Bandung Jl. Ganesha No. 10, Bandung, West Java, Indonesia 40132 e-mail: * 1 yusuf@sith.itb.ac.id 2 wahyuzady@gmail.com 3 lestariaprina@gmail.com 4 nataliearazella@gmail.com *Corresponding author