Wastewater treatment is a major environmental issue, requiring effective and sustainable solutions around the world. In this study, plantain peel is used as a natural coagulant-flocculant in the wastewater treatment process. To do this, decoctions of ripe and unripe banana peels were prepared. The main chemical constituents were then identified using characteristic reagents. The total oses, total phenolic compounds, and condensed tannins were measured using the phenol-sulfuric acid, Folin-Ciocalteu, and vanillin methods in an acidic medium, respectively. Finally, the flocculant-coagulant properties of the different aqueous extracts were evaluated using the Jar Test method. The yields of dry crude extracts were 17.91% and 25.4% for ripe and unripe banana peels, respectively. Qualitative tests revealed the presence of polysaccharides, alkaloids, tannins, and lignins in both extracts. The various assays performed showed that ripe banana peels contain significant levels of total oses, total phenolic compounds, and condensed tannins, with values of 621.297 µg EG/mg, 72.514 µg EAG/mg, and 17.315 μg EC/mg of dry extract, respectively. Fourier Transform Infrared (FTIR) analyses of the two plantain peel extracts qualitatively revealed the presence of certain functional groups characteristic of polysaccharides and phenolic compounds. The evaluation of flocculant-coagulant properties showed a better reduction in wastewater turbidity with a reduction rate of 96.93% and 88.81% at pH = 2 for concentrations of 40 µg/mL and 60 µg/mL of dry extracts from ripe and unripe banana peels, respectively. The same extracts have been shown to be effective in the reduction of organic load COD and BOD 5 and the removal of certain heavy metals such as Zn, Mn, and Hg.
Mutegoa, E. (2024) Efficient Techniques and Practices for Wastewater Treatment: An Update. Discover Water , 4, Article No. 69. https://doi.org/10.1007/s43832-024-00131-8
Qadir, M., Drechsel, P., Jiménez Cisneros, B., Kim, Y., Pramanik, A., Mehta, P., et al . (2020) Global and Regional Potential of Wastewater as a Water, Nutrient and Energy Source. Natural Resources Forum , 44, 40-51. https://doi.org/10.1111/1477-8947.12187
Jones, E.R., van Vliet, M.T.H., Qadir, M. and Bierkens, M.F.P. (2021) Country-Level and Gridded Estimates of Wastewater Production, Collection, Treatment and Reuse. Earth System Science Data , 13, 237-254. https://doi.org/10.5194/essd-13-237-2021
Marsault, F., Naylor, B. and Reigue, A. (2013) Wastewater Treatment and Recovery: The Example of the Rochefort Lagooning Plant. CERES-ERTI.
Boughou, N., Majdy, I., Cherkaoui, E., Mohamed, K. and Nounah, A. (2016) The Physico-Chemical Treatment by Coagulation-Flocculation Releases of Slaughterhouse Wastewater in the City of Rabat (Morocco). Der Pharma Chemica , 8, 93-99.
Seghairi, N., Mimeche, L., Bouzid, A. and Ayachi, Y. (2017) Traitement des eaux usées par coagulation-floculation en utilisant le sulfate d’aluminium comme coagulant. Journal of Water and Environmental Sciences , 1, 230-234.
Koul, B., Bhat, N., Abubakar, M., Mishra, M., Arukha, A.P. and Yadav, D. (2022) Application of Natural Coagulants in Water Treatment: A Sustainable Alternative to Chemicals. Water , 14, Article No. 3751. https://doi.org/10.3390/w14223751
Lemma, M., Kalsido, A.W. and Wamolo Wotee, M. (2024) Removal of River Water Turbidity and Total Dissolved Solids Using Natural Coagulants Derived from Banana Peel and Moringa stenopetala Seed. AQUA — Water Infrastructure , Ecosystems and Society , 73, 1467-1493. https://doi.org/10.2166/aqua.2024.130
Hikal, W.M., Said-Al Ahl, H.A.H., Bratovcic, A., Tkachenko, K.G., Sharifi-Rad, J., Kačániová, M., et al . (2022) Banana Peels: A Waste Treasure for Human Being. Evidence - Based Complementary and Alternative Medicine , 2022, Article ID: 7616452. https://doi.org/10.1155/2022/7616452
Thangam, R., Suresh, V. and Kannan, S. (2014) Optimized Extraction of Polysaccharides from Cymbopogon citratus and Its Biological Activities. International Journal of Biological Macromolecules , 65, 415-423. https://doi.org/10.1016/j.ijbiomac.2014.01.033
Bishnoi, S., Sharma, S. and Agrawal, H. (2023) Exploration of the Potential Application of Banana Peel for Its Effective Valorization: A Review. Indian Journal of Microbiology , 63, 398-409. https://doi.org/10.1007/s12088-023-01100-w
Sani, M.U. and Muhammad, A.K. (2021) Assessment of Phytochemical and Mineral Composition of Unripe and Ripe Plantain ( Musa paradisiaca ) Peels. African Journal of Food Science , 15, 107-112. https://doi.org/10.5897/ajfs2017.1680
Yao, A.K., Koffi, D.M., Irié, Z.B. and Niamke, S.L. (2014) Preservation of Green Plantains (Musa AAB) Using Polyethylene Films of Different Thicknesses. Journal of Animal and Plant Sciences , 23, 3677-3690.
Seymour, G.B. (1993) Banana. In: Seymour, G.B., et al ., Eds., Biochemistry of Fruit Ripening , Springer, 83-106. https://doi.org/10.1007/978-94-011-1584-1_3
Panigrahi, N., Thompson, A.J., Zubelzu, S. and Knox, J.W. (2021) Identifying Opportunities to Improve Management of Water Stress in Banana Production. Scientia Horticulturae , 276, Article ID: 109735. https://doi.org/10.1016/j.scienta.2020.109735
Diawara, M. (2022) Biological Properties of Guinean Bananas. Ph.D., Université de Montpellier.
del Mar Verde Méndez, C., Forster, M.P., Rodríguez-Delgado, M.Á., Rodríguez-Rodríguez, E.M. and Díaz Romero, C. (2003) Content of Free Phenolic Compounds in Bananas from Tenerife (Canary Islands) and Ecuador. European Food Research and Technology , 217, 287-290. https://doi.org/10.1007/s00217-003-0762-8
Zhang, J., Li, P., Yu, Y., Xu, Y., Jia, W. and Zhao, S. (2023) A Review of Natural Polysaccharides-Based Flocculants Derived from Waste: Application Efficiency, Function Mechanism, and Development Prospects. Industrial & Engineering Chemistry Research , 62, 15774-15789. https://doi.org/10.1021/acs.iecr.3c02563
Schmitt, J. and Flemming, H. (1998) Ftir-Spectroscopy in Microbial and Material Analysis. International Biodeterioration & Biodegradation , 41, 1-11. https://doi.org/10.1016/s0964-8305(98)80002-4
Zhbankov, R.G., Firsov, S.P., Buslov, D.K., Nikonenko, N.A., Marchewka, M.K. and Ratajczak, H. (2002) Structural Physico-Chemistry of Cellulose Macromolecules. Vibrational Spectra and Structure of Cellulose. Journal of Molecular Structure , 614, 117-125. https://doi.org/10.1016/s0022-2860(02)00252-1
Pattnaik, P. and Dangayach, G.S. (2019) Sustainability of Wastewater Management in Textile Sectors: A Conceptual Framework. Environmental Engineering and Management Journal , 18, 1947-1965. https://doi.org/10.30638/eemj.2019.186
Ho, K., Lau, S.Y., Ting, L.H., Zahir, A., Lam, M.K., Choy, S.Y., et al . (2025) Review of Starch-Based Coagulants for Water Treatment: Mechanisms, Extraction and Surface Modification. Next Sustainability , 5, Article ID: 100083. https://doi.org/10.1016/j.nxsust.2024.100083
Lwasa, A., Mdee, O.J., Ntalikwa, J.W. and Sadiki, N. (2024) Performance Analysis of Plant-Based Coagulants in Water Purification: A Review. Discover Water , 4, Article No. 108. https://doi.org/10.1007/s43832-024-00171-0
Prodanović, J.M., Nastić, N.M., Šćiban, M.B., Lukić, D.V., Vasić, V.M. and Blagojev, N.T. (2025) An Investigation into the Factors Influencing the Effectiveness of a Biodegradable Natural Coagulant Derived from Phaseolus Vulgaris Seeds and Coagulation Mechanism. Sustainability , 17, Article No. 1372. https://doi.org/10.3390/su17041372
Cortés-Ferré, H.E., Arredondo-Ochoa, T. and Gaytán-Martínez, M. (2025) Polysaccharides-Polyphenolic Interactions: Formation, Functionality and Applications. Trends in Food Science & Technology , 163, Article ID: 105117. https://doi.org/10.1016/j.tifs.2025.105117
Mishra, A., Yadav, A., Agarwal, M. and Rajani, S. (2004) Polyacrylonitrile-Grafted Plantago Psyllium Mucilage for the Removal of Suspended and Dissolved Solids from Tannery Effluent. Colloid & Polymer Science , 282, 300-303. https://doi.org/10.1007/s00396-003-0895-0
Badawi, A.K., Salama, R.S. and Mostafa, M.M.M. (2023) Natural-Based Coagulants/Flocculants as Sustainable Market-Valued Products for Industrial Wastewater Treatment: A Review of Recent Developments. RSC Advances , 13, 19335-19355. https://doi.org/10.1039/d3ra01999c
Oyeyinka, B.O. and Afolayan, A.J. (2019) Comparative Evaluation of the Nutritive, Mineral, and Antinutritive Composition of Musa sinensis L. (Banana) and Musa paradisiaca L. (Plantain) Fruit Compartments. Plants , 8, Article No. 598. https://doi.org/10.3390/plants8120598
Azamzam, A.A., Rafatullah, M., Yahya, E.B., Ahmad, M.I., Lalung, J., Alam, M., et al . (2022) Enhancing the Efficiency of Banana Peel Bio-Coagulant in Turbid and River Water Treatment Applications. Water , 14, Article No. 2473. https://doi.org/10.3390/w14162473
Dharsana, M. and Jose, J.P.A. (2023) Application of Nano-Banana Peel Bio-Coagulant for the Treatment of Turbid and River Water. Chemistry Africa , 7, 429-441. https://doi.org/10.1007/s42250-023-00732-1
Sri, D.P. and Asha, R.N.R. (2021) Evaluation of Wastewater Treatment Using Banana Fruit Peel Powder as Natural Coagulant. International Research Journal of Innovations in Engineering and Technology , 5, 58-65.