Monoterpenes released from fruit, plant, and vegetable systems.

Mohammad Iqbal,Jeong Ahn,Ki-Hyun Kim

doi:10.3390/s141018286

Mohammad Iqbal, Jeong Ahn + Show 1 more

Open Access

https://doi.org/10.3390/s141018286

Copy DOI

Abstract

To quantify the emission rate of monoterpenes (MTs) from diverse natural sources, the sorbent tube (ST)-thermal desorption (TD) method was employed to conduct the collection and subsequent detection of MTs by gas chromatography. The calibration of MTs, when made by both mass spectrometric (MS) and flame ionization detector (FID), consistently exhibited high coefficient of determination values (R2 > 0.99). This approach was employed to measure their emission rate from different fruit/plant/vegetable (F/P/V) samples with the aid of an impinger-based dynamic headspace sampling system. The results obtained from 10 samples (consisting of carrot, pine needle (P. sylvestris), tangerine, tangerine peel, strawberry, sepals of strawberry, plum, apple, apple peel, and orange juice) marked α-pinene, β-pinene, myrcene, α-terpinene, R-limonene, γ-terpinene, and p-cymene as the most common MTs. R-limonene was the major species emitted from citrus fruits and beverages with its abundance exceeding 90%. In contrast, α-pinene was the most abundant MT (37%) for carrot, while it was myrcene (31%) for pine needle. The overall results for F/P/V samples confirmed α-pinene, β-pinene, myrcene, α-terpinene, and γ-terpinene as common MTs. Nonetheless, the types and magnitude of MTs released from fruits were distinguished from those of vegetables and plants.

Highlights

The environmental significance of biogenic volatile organic compounds (BVOCs) is well known for their potent role in the formation of the tropospheric ozone like their anthropogenic counterparts [1,2,3]
The system performance of both the gas chromatography (GC)/mass spectrometric (MS) and GC/flame ionization detector (FID) methods was examined in the analysis of MTs
In the analysis of headspace collected from pine needle, α-pinene, myrcene, and R-limonene were dominant, while almost all other target MTs were detected above DL

Summary

Introduction

The environmental significance of biogenic volatile organic compounds (BVOCs) is well known for their potent role in the formation of the tropospheric ozone like their anthropogenic counterparts [1,2,3]. As the major components of BVOC, monoterpenes (MTs: C10H16) are formed as the secondary metabolites of plants with two isoprene units (C5H8). They are the key components of the fragrant or essential oils obtained from vegetables (e.g., carrot), plant segments (e.g., pine needle), and fruits [4,5,6]. The flavor of highly complex beverages (e.g., wines and juices) is dominated by essential fragrance components like MTs [6,7,8]. In light of the potent role of MTs in atmospheric chemistry, researchers have had a great deal of interest in their quantification as tracers of organic aerosols [10]. In laboratory-based quantitation of MTs, gas chromatography (GC) equipped with mass spectrometric (MS) or flame ionization detector (FID)

Methods

Results

Conclusion