Effects of Coated Capillary Column, Derivatization, and Temperature Programming on the Identification of Carica papaya Seed Extract Composition Using GC/MS Analysis

Abstract

Some of the common practices to assess the composition of plant extract, including Carica papaya seed extract (CPSE) are direct injection of the extract, compound separation using polyethylene glycol capillary column (DB-WAX), and non-linear-temperature programming (NLTP) of GC/MS analysis. This study specifically compared the coating of capillary column, sample derivatization, and temperature programming of GC/MS to determine the composition of CPSE. The retention indices (RI) of the detected compounds were determined and compared to the reference RI. In particular, 5% phenyl–95% methylpolysiloxane (HP-5MS)-, DB-WAX-, and biscyanopropyl polysiloxane (HP-88)-coated capillary columns were used to identify the composition of CPSE. For this study, HP-5MS column, which separated the highest number of compounds (26 compounds) from CPSE, was deemed as the most suitable column. The GC/MS analysis of derivatized CPSE identified 21 compound groups, where fatty acids and fatty acid methyl esters served as the major compounds (80.23%), followed by these compounds in decreasing order: amides > nitriles > sterols > fatty aldehydes > organic acids. A stronger correlation determination between the carbon number and alkane retention time of linear-temperature programming (LTP) (R2 = 0.9859) was found, as compared to its correlation determination with NLTP (R2 = 0.9175), which exhibited an almost equal RI of LTP to the reference RI. Conclusively, GC/MS analysis for the derivatized CPSE using HP-5MS column separation and LTP is highly recommended. • This study (1) analyzed the composition of Carica papaya seed extract (CPSE) by comparing sample derivatization, type of column, and temperature programming of the GC/MS and (2) developed retention indices (RI) of volatiles and TMS-formed compounds of CPSE using linear (LTP) and non-linear (NLTP) temperature programming. • HP-5MS column separated the highest number of compounds (26 compounds), followed by DB-WAX (13 compounds) and HP-88 (11 compounds) at 90% similarity match towards NIST 11 library. • Twenty-one groups of compounds were identified in derivatized and non-derivatized CPSE using GC/MS, where fatty acids and fatty acid methyl esters were the dominant compounds (80.23%). • The RI for LTP was almost equal to the reference RI as reported from previous literature, while RI for NLTP showed different values from the reference RI due to the stronger correlation determination between carbon number against retention time of alkane of LTP (R2 > 0.9859) as compared to NLTP (R2 > 0.9175). • This study recommended a GC/MS analysis of derivatized CPSE with HP-5MS column separation and LTP.