Assessment of the Antioxidant Potential of Anthocyanin-Rich Extract of Eggplant (Solanum melongena L.) and Evaluation of its Antimicrobial Activity


  • Sameerah A. Zearah Department of Chemistry, College of Science, Basra University



Antifungal, Antibacterial, Antioxidant, Anthocyanin, Solanum melongena L., Eggplant


Eggplant peels (Solanum melongena L.), particularly the purple variety, contain high levels of anthocyanins, a type of flavonoid with promising medicinal properties. This study aims to investigate the antioxidant and antimicrobial potentials of anthocyanin-rich extract of eggplant peels. The anthocyanin-rich extract was obtained by maceration under acidic conditions. Preliminary qualitative phytochemical screening of the extract was done following standard procedures. The antimicrobial activity of the extract was evaluated against two bacterial (Escherichia coli and Staphylococcus aureus) and two fungal (Aspergillus niger and Candida
albicans) strains using the agar well diffusion method. The antioxidant activity of the extract was assessed by the β-carotene bleaching assay. Preliminary phytochemical analysis confirmed the presence of anthocyanin, a type of flavonoid, in the purple-coloured peel extract. The extract demonstrated antibacterial activity against gram-negative (Escherichia coli) and gram-positive
(Staphylococcus aureus) bacterial strains. The inhibition zone diameters were 22 mm and 18 mm at 100 mg/mL and 10 mg/mL, respectively against both bacterial strains. The minimum inhibitory concentration (MIC) was 0.1 mg/mL for Staphylococcus aureus and 0.01 mg/mL for Escherichia coli. The extract demonstrated a concentration-dependent antifungal activity against Aspergillus
niger and Candida albicans with MIC of 0.1 mg/mL for both fungal strains. The extract showed potent antioxidant activity with percentage activity as high as 74.26%. The anthocyanin content in the extract contributes significantly to its antioxidant activity. These observations therefore suggest the potential for use of eggplant extract as natural antimicrobial and antioxidant agents


Alappat B and Alappat J. Anthocyanin pigments: Beyond aesthetics. Molecules. 2020; 25(23):5500.

Vidana Gamage GC, Lim YY, Choo WS. Sources and relative stabilities of acylated and nonacylated anthocyanins in beverage systems. J Food Sci Technol. 2022; 59(3):831-845.

Mattioli R, Francioso A, Mosca L, Silva P. Anthocyanins: A comprehensive review of their chemical properties and health effects on cardiovascular and neurodegenerative diseases. Molecules. 2020; 25(17):3809.

Bub A, Watzl B, Heeb D, Rechkemmer G, Briviba K. Malvidin-3-glucoside bioavailability in humans after ingestion of red wine, dealcoholized red wine and red grape juice. Eur J Nutr. 2001; 40:113-120.

Dhiman S, Kumar V, Mehta CM, Gat Y, Kaur S. Bioactive compounds, health benefits and utilisation of Morus spp.– a comprehensive review. J Horticult Sci Biotechnol. 2020; 95(1):8-18.

He K, Li X, Chen X, et al. Evaluation of antidiabetic potential of selected traditional Chinese medicines in STZ-induced diabetic mice. J Ethnopharmacol. 2011; 137(3):1135- 1142.

Algarra M, Fernandes A, Mateus N, de Freitas V, da Silva JCGE, Casado J. Anthocyanin profile and antioxidant capacity of black carrots (Daucus carota L. ssp. sativus var. atrorubens Alef.) from Cuevas Bajas, Spain. J Food Compos Anal. 2014; 33(1):71-76.

Wang H, Cao G, Prior RL. Oxygen radical absorbing capacity of anthocyanins. J Agric Food Chem. 1997; 45(2):304-309.

Stintzing FC, Stintzing AS, Carle R, Frei B, Wrolstad RE. Color and antioxidant properties of cyanidin-based anthocyanin pigments. J Agric Food Chem. 2002; 50(21):6172-6181.

Terahara N, Callebaut A, Ohba R, Nagata T, OhnishiKameyama M, Suzuki M. Acylated anthocyanidin 3- sophoroside-5-glucosides from Ajuga reptans flowers and the corresponding cell cultures. Phytochem. 2001; 58(3):493-500.

Tamura H and Yamagami A. Antioxidative activity of monoacylated anthocyanins isolated from Muscat Bailey A grape. J Agric Food Chem. 1994; 42(8):1612-1615.

Kazmi S, Habib M, Bashir K, Jan S, Kumar S, Jan K. Natural Anthocyanins from Subtropical Fruits for Cardiac Disease Prevention. Anthocyanins Subtrop Fruits Chem Prop Process Heal Benefits. 2023; 11.

Ju Z and Howard LR. Subcritical water and sulfured water extraction of anthocyanins and other phenolics from dried red grape skin. J Food Sci. 2005; 70(4):S270-S276.

Anbuselvi S, Kumar SS, MA N, Esther R. Extraction of Nasunin from Different Colored Egg Plant Peels and its Phytochemical Screening by GC-MS. Res J Pharm Technol. 2019; 12(6):2881-2884.

Waterman PG. Phytochemical Dictionary. A Handbook of Bioactive Compounds from Plants: Edited by JB Harborne and H. Baxter, Taylor & Francis, London, 1993; 791 p.

Khandelwal K. Practical Pharmacognosy. Pragati Books Pvt. Ltd.; 2008.

Abdel-Rahman LH, Abu-Dief AM, Hassan Abdel-Mawgoud AA. Development, structural investigation, DNA binding, antimicrobial screening and anticancer activities of two novel quari-dentate VO(II) and Mn (II) mononuclear complexes. J King Saud Univ Sci. 2019; 31(1):52-60.

Al-Salami BK, Hameed AJ, Al-Rubaie AZ. Synthesis, antimicrobial, antioxidant and structural studies of some new sulfa drug containing an azo-azomethine group. Egypt J Chem. 2021; 64(2):751-759.

Al-Atbi HS, Jaraf HA, Sabti AB. Synthesis, Antibacterial, and Antioxidant Activities of Some Schiff Bases. Trop J Nat Prod Res. 2022; 6(12):1925-1929.

Margaret OI, Angela EO, Olayemi AO, Emmanuel OA, Folashade OJ. Antifungal activity of telfaira occidentalis extracts on some phytopathogenic fungi isolated from Carica papaya. Published online 2020.

Ahmeda A, Hossain MA, Zhari I. Antioxidant properties of the isolated flavonoids from the medicinal plant Phyllanthus niruri. Asian J Food Agro-Indust. 2009; 2(3):373-381.

Khoo HE, Azlan A, Tang ST, Lim SM. Anthocyanidins and anthocyanins: Colored pigments as food, pharmaceutical ingredients, and the potential health benefits. Food Nutr Res. 2017; 61(1):1361779.

Condurache Lazăr NN, Croitoru C, Enachi E, Bahrim GE, Stănciuc N, Râpeanu G. Eggplant Peels as a Valuable Source of Anthocyanins: Extraction, Thermal Stability and Biological Activities. Plants (Basel). 2021; 10(3):577.

Al-Abdulla BY and Oleiwi SD. Estimation of some phytochemicals in extract of eggplant peels and cabbage leaves and using of pigment of them in drinks industry. Mesopotamia J Agric. 2019; 47(2):128-138.

Salamatullah AM, Alkaltham MS, Hayat K, et al. Bioactive and antimicrobial properties of eggplant (Solanum melongena L.) under microwave cooking. Sustainab. 2021; 13(3):1519.

Bokhari FM. Antifungal activity of some medicinal plants used in Jeddah, Saudi Arabia. Mycopathol. 2009; 7(1):51-57.

Feng L juan, Zhe WAN, Wang X hong, Li R yu, Wei LIU. Relationship between antifungal resistance of fluconazole resistant Candida albicans and mutations in ERG11 gene. Chin Med J (Engl). 2010; 123(5):544-548.

Das J, Lahan JP, Srivastava RB. Solanum melongena: A potential source of antifungal agent. Indian J Microbiol. 2010; 50:62-69.

Niño-Medina G, Urías-Orona V, Muy-Rangel MD, Heredia JB. Structure and content of phenolics in eggplant (Solanum melongena)-a review. South Afr J Bot. 2017; 111:161-169.

Islam MT. Phytochemical information and pharmacological activities of Okra (Abelmoschus esculentus): A literature‐ based review. Phyther Res. 2019; 33(1):72-80.

Horincar G, Enachi E, Bolea C, Râpeanu G, Aprodu I. Valueadded lager beer enriched with eggplant (Solanum melongena L.) peel extract. Molecules. 2020; 25(3):731.

Chepkirui C, Matasyoh JC, Wagara IN, Nakavuma J. Antifungal activity of flavonoids isolated from Monanthotaxis littoralis against mycotoxigenic fungi from maize. Published online 2014.

Chua EG, Parolia A, Ahlawat P, Pau A, Amalraj FD. Antifungal effectiveness of various intracanal medicaments

against Candida albicans: an ex-vivo study. BMC Oral Health. 2014; 14(1):1-8.

Lin HC, Tsai SH, Chen CS, Chang YC, Lee CM, Lai ZY, Lin CM. Structure-activity relationship of counarin derivatives on xanthine oxidase-inhibiting and free radical-scavenging activities. Biochem Pharmacol. 2008; 75:1416–1425.

Gođevac D, Tešević V, Veličković M, Vujisić L, Vajs V, Milosavljević S. Polyphenolic compounds in seeds from some grape cultivars grown in Serbia. J Serbian Chem Soc. 2010; 75(12):1641-1652.

Giusti MM and Wrolstad RE. Acylated anthocyanins from edible sources and their applications in food systems. Biochem Eng J. 2003; 14(3):217-225.

Nayanathara AR, Mathews A, Aalolam KP, Reshma JK. Evaluation of total phenol, flavonoid and anthocyanin content in different varieties of eggplant. Emergent Life Sci Res. 2016; 2:63-65.

Singh AP, Wang Y, Olson RM, et al. LC-MS-MS analysis and the antioxidant activity of flavonoids from eggplant skins grown in organic and conventional environments. Food Nutr Sci. 2017;8(09):873.




How to Cite

Zearah, S. A. (2024). Assessment of the Antioxidant Potential of Anthocyanin-Rich Extract of Eggplant (Solanum melongena L.) and Evaluation of its Antimicrobial Activity. Tropical Journal of Natural Product Research (TJNPR), 8(3), 6558–6562.