Integrated dual-pathway valorization of Feijoa sellowiana: Adsorption of safranin O and methylene blue and antioxidant capacity evaluation
Process Biochemistry, cilt.172, ss.1-20, 2027 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 172
- Basım Tarihi: 2027
- Doi Numarası: 10.1016/j.procbio.2026.10.012
- Dergi Adı: Process Biochemistry
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, Chemical Abstracts Core, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Sayfa Sayıları: ss.1-20
- Anahtar Kelimeler: Adsorption, Antioxidant capacity, Cationic dyes, Feijoa sellowiana
- Yıldız Teknik Üniversitesi Adresli: Evet
Özet
This study presents the first integrated dual-pathway valorization of Feijoa sellowiana leaf simultaneously as a biosorbent for cationic dye removal and a source of antioxidants. The leaf was characterized by FT-IR, SEM, and XRD and tested in batch adsorption experiments for Safranin O (SO) and Methylene Blue (MB). Optimal conditions were pH 8, dosage of 0.05 g/50 mL, and contact times of 30 min (SO) and 45 min (MB), yielding removal efficiencies of ~85% and ~89%, respectively. Langmuir equilibrium modeling gave maximum adsorption capacities of 320.7 ± 17.6 mg/g (SO) and 328.9 ± 18.1 mg/g (MB) at 318 K, surpassing many unmodified lignocellulosic biosorbents. Kinetics followed the pseudo-second-order model; thermodynamics confirmed spontaneous, endothermic adsorption in a predominantly non-covalent interaction regime, supported by low activation energies and D–R adsorption energies. In the sequential valorization strategy, ultrasound-assisted extraction first recovered crude extracts; the lignocellulosic residue was then dried and used as biosorbent, ensuring full feedstock utilization. The ethanol extract exhibited 276.67 μg pyrocatechol equivalent mg⁻¹ phenolics, 526.79 μg catechin equivalent mg⁻¹ flavonoids, 81.63% DPPH scavenging activity, and 501.14 μg ascorbic acid equivalent mg⁻¹ total antioxidant capacity. This dual-function, zero-waste approach distinguishes the present work from conventional single-function biosorbent research and aligns with circular economy principles.