Chemometric approaches for the optimization of headspace-solid phase microextraction to analyze volatile compounds in coriander (Coriandrum sativum L.)

Headspace-solid phase microextraction (HS-SPME) conditions for the gas chromatography-mass spectrometry (GC-MS) analysis of volatiles in coriander aerial part were systematically optimized for the first time using chemometric approaches. Single factor test preliminarily determined the superior level of each parameter. Plackett-Burman factorial design further identified the three most significant variables (heating temperature > extraction time > CaCl2 amount). Then, Box-Behnken design of response surface methodology (RSM) was applied to obtain the optimal extraction conditions and corresponding model equation (R-2 = 0.9793-0.9809). Verification results with less than 5% of relative standard deviations (RSDs) indicated that this extraction procedure had good repeatability and intermediate precision. A total of 67 volatiles were identified from coriander, mainly including aldehydes, alcohols, hydrocarbons and esters. Among them, the proportion of aldehydes was highest approximately 83.76%, and (E)-2-tetradecenal was the most abundant analyte, followed by (Z)-9-hexadecenal, 2-dodecenal and (E)-2-tridecenal. There were 21 characteristic volatiles with the odor activity values (OAVs) greater than 1, which contributed greatly to coriander flavor. Moreover, citrus aroma was the strongest scent, afterwards were fatty and unpleasant soapy odors. This research provided an advanced technical support for the extraction and analysis of coriander volatiles.

Automated summary

This study systematically optimized the HS-SPME conditions for the analysis of volatiles in coriander aerial part using chemometric approaches. A total of 67 volatiles were identified, with 21 characteristic volatiles contributing significantly to coriander flavor. The research provided advanced technical support for the extraction and analysis of coriander volatiles.