Rapid methods for extracting and quantifying phenolic compounds in citrus rinds.

Area of Science:

• Agricultural and Food Chemistry
• Analytical Chemistry

Background:

• Conventional methods for extracting and quantifying phenolic compounds in citrus rinds are often time-consuming.
• Phenolic compounds in citrus rinds possess significant health benefits and industrial applications.

Purpose of the Study:

• To develop rapid and efficient methods for extracting and quantifying phenolic compounds from citrus rinds.
• To compare the effectiveness of different solvent combinations and extraction times.

Main Methods:

• Extraction of freeze-dried citrus rind powder using three solvent combinations: ethanol:H2O, methanol:H2O:HCl, and DMSO:methanol.
• Ultrasonic water bath extraction at 35°C for 10, 20, and 30 minutes.
• Quantification of phenolic compounds using High-Performance Liquid Chromatography (HPLC) with a diode array detector.

Main Results:

• Extraction with methanol:H2O:HCl for 30 minutes provided the optimal yield of targeted phenolic acids.
• The dominant phenolic compound identified was hesperidin, with concentrations ranging from 7500 to 32,000 μg/g DW.
• The highest yield of flavanone glycosides (FGs) was achieved using DMSO:methanol for 10 minutes.

Conclusions:

• The developed extraction and quantification methods are significantly faster and more efficient than conventional techniques.
• The methanol:H2O:HCl method is recommended for optimal extraction of phenolic acids, while DMSO:methanol is effective for flavanone glycosides.
• The high sensitivity of the HPLC method, indicated by low limits of detection and quantification, ensures reliable results.