Green valorization approach of Citrus limetta peels by ultrasound-assisted enzymatic extraction for recovery of dietary fibers: Optimization, physicochemical, structural, functional, and thermal properties
Valorization of citrus by-products for the extraction of dietary fibers can help neutralize increasing environmental issues and expedite their value-addition and sustainable applications, thereby promoting circular economy approach. In the present study, dietary fibers were recovered from Citrus limetta peels using green ultrasound-assisted enzymatic extraction (UAEE) technique and response surface methodology (RSM) was utilized to optimize the extraction process. The experimental yield value (insoluble dietary fiber = 55.97% and soluble dietary fiber = 11.83%) was close to the predicted yield value (insoluble dietary fiber = 55.89 ± 0.46% and soluble dietary fiber = 12.04 ± 0.21%) under the optimal conditions of 21.5 min sonication time, 30 v/w solid–liquid ratio, temperature 41 °C, and 31% amplitude, thus confirming the validity of the model. In addition, various proximate, functional, thermal, structural, and antioxidant properties of fibers recovered using both techniques were investigated and compared. Higher TPC, DPPH scavenging activity, water/oil holding, cation exchange, and swelling capacities of UAEE extracted fibers as compared to ALE fibers. Moreover, thermal, XRD, and SEM analysis showed that dietary fiber extracted using UAEE exhibited higher thermal stability and crystalline nature as well as showed loose, porous, and wrinkled surface than ALE-extracted fibers, respectively. In addition, difference in peak positions and intensities for characteristic bands of all fiber samples were observed. Therefore, these results suggested that UAEE can be used as a promising green extraction technique for the recovery of dietary fibers from C. limetta peels.
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Authors and Affiliations
- Department of Biotechnology, Anand School of Engineering and Technology, Sharda University, Agra, 282007, India Divyani Panwar
- Food Biotechnology Research Laboratory, Department of Food Engineering and Technology, Sant Longowal Institute of Engineering and Technology, Longowal, 148106, Punjab, India Parmjit S. Panesar
- Department of Chemistry, Sant Longowal Institute of Engineering and Technology, Longowal, 148106, Punjab, India Harish K. Chopra
- Divyani Panwar
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Divyani Panwar: conceptualization, investigation, formal analysis, data curation, writing—original draft preparation, writing—reviewing and editing.
Parmjit S. Panesar: conceptualization, resources, supervision, funding acquisition, writing—reviewing and editing.
Harish K. Chopra: resources and supervision.
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Highlights
• Dietary fiber was extracted from Citrus limetta peels using alkaline and ultrasound-assisted extraction techniques.
• Ultrasound-assisted enzymatic extraction method was optimized using Box-Behnken design.
• Extraction techniques affect proximate, technological, structural, and functional properties of fiber.
• Dietary fiber extracted using green technique exhibited superior thermal properties.
• Citrus peel dietary fiber could be utilized for the development of value-added functional products.
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Panwar, D., Panesar, P.S. & Chopra, H.K. Green valorization approach of Citrus limetta peels by ultrasound-assisted enzymatic extraction for recovery of dietary fibers: Optimization, physicochemical, structural, functional, and thermal properties. Biomass Conv. Bioref. (2024). https://doi.org/10.1007/s13399-024-05963-x
- Received : 09 May 2024
- Revised : 11 July 2024
- Accepted : 16 July 2024
- Published : 05 August 2024
- DOI : https://doi.org/10.1007/s13399-024-05963-x
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Keywords
- Citrus peel
- Dietary fiber
- Ultrasound-assisted enzymatic extraction
- Box-Behnken design
- Alkaline extraction
- Characterization