Application of green technologies for the extraction of phytocompounds from C. pseudolimon residues; an approach for biological characterization

The citrus residue (peel and pomace), which is regarded as waste, is a promising source of bioactive compounds. Proper management through sustainable strategies is required to utilize citrus residue for value addition. In the present study, the efficiency of the shaking water bath extraction (SWE), microwave-assisted extraction (MAE), and ultrasonication-assisted (UAE) techniques on the extraction of phytocompounds from C. pseudolimon peel and pomace were evaluated. The ranking analysis was used to study the effect of the process parameters on the extraction of phyto-compounds in terms of total phenols, flavonoids, antioxidant activity, and antidiabetic activity. Compared to the different techniques MAE (500 W; time 120 s; solid-liquid ratio 1:15 and pH 5.5) exhibited the highest rate of extraction for citrus peel phytocompounds, whereas UAE (300 W; time 30 min; solid-liquid ratio 1:15 and pH 5.5) was found more effective for citrus pomace phytocompounds extraction. However, minimum extraction was observed in the SWE technique for both samples. FTIR analysis also confirmed the quantitative data. Structural morphol-ogy revealed the better structural opening in MAE for citrus peel and in UAE for citrus pomace. In a nutshell, this study will provide the basis for a waste-to-profit solution using green technolo-gies.