Biochemical Transformation, Functional Properties, and Digestibility of Alligator Weed Fermented with Rhizopus Oligosporus for Nile Tilapia
Received: 26 December 2025 | Revised: 25 January 2026, 31 January 2026, and 3 February 2026 | Accepted: 4 February 2026 | Online: 4 April 2026
Corresponding author: Veryl Hasan
Abstract
This study examines the impact of solid-state fermentation of alligator weed using Rhizopus oligosporus on the chemical composition, antioxidant activity, antibacterial properties, and apparent digestibility in Nile Tilapia. Fermentation was conducted for 3 and 5 days, with unfermented material used as a control specimen. Fermentation significantly increased crude protein content and reduced crude fiber and antinutritional factors, including phytate, tannin, and oxalate. The fermented samples exhibited enhanced antioxidant capacity, as evidenced by increased phenolic content and radical-scavenging activity. Antibacterial activity against major fish pathogenic bacteria was also improved following fermentation. Digestibility trials showed significantly higher Apparent Digestibility Coefficients (ADCs) of dry matter, protein, and energy in diets containing fermented alligator weed, with the highest values observed after 5 days of fermentation. These results demonstrate that Rhizopus oligosporus fermentation effectively improves the nutritional quality, functional properties, and digestibility of alligator weed, indicating its potential application as a sustainable functional feed ingredient for Nile Tilapia aquaculture.
Keywords:
alligator weed, antioxidant activity, digestibility, fermentation, life below water, Nile TilapiaDownloads
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Copyright (c) 2026 R. Adharyan Islamy, Diana Aisyah, Ayu Winna Ramadhani, Hadiana Hadiana, Andi Masriah, Norshida Ismail, Ahmad Syazni Kamarudin, Veryl Hasan
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