Rapid Collection of Floral Fragrance Volatiles using a Headspace Volatile Collection Technique for GC-MS Thermal Desorption Sampling

Summary

Here, we present a protocol for collecting the floral fragrance volatiles from blooming flowers, using a non-destructive sampling procedure.

Abstract

Fragrances of many flower families have been sampled and the volatiles analyzed. Knowing the compounds that make up the fragrances can be an important step to conservation of flowers that are threatened or endangered. Because floral fragrance is critical for attracting pollinators, this method could be used to better understand or even enhance pollination. We present a protocol using a portable charcoal air filter and vacuum to collect floral fragrance volatiles, which are then analyzed by a GC-MS. By using this method, fragrance volatiles can be sampled using a non-destructive method with a machine that is easily transported. This methodology uses a rapid sampling procedure, cutting sampling time down from 2-3 hours to approximately 10 minutes. Using GC-MS, the fragrance compounds can be identified individually, based on authentic standards. The steps used for collecting fragrance and control data are presented, from material setup to collecting the data output.

Introduction

Flowers typically produce a fragrance used to attract pollinators. These fragrances are made up of many chemical compounds all acting together as a floral blend^1,2,3. Without these fragrances, flowers would be less likely to pass on their genetic information using pollinators. Floral fragrance has been documented in many flowering plant families, with Orchidaceae being one of the more common families studied⁴. To understand the role of floral fragrance in pollination, it is important to nondestructively collect and analyze the chemical compoun....

Protocol

NOTE: Perfumes or scented lotions and products must not be worn during any of these procedures.

1. Flower selection

NOTE: Flowers used can be either naturally growing in the environment or kept under artificial environmental conditions. Temperature, humidity, and light level during collection can vary based on the specific flower species used, and what type of data is being collected. For example, data has been collected during the day and at night for the same flower.......

Discussion

Though this technique is incredibly valuable for its sampling speed and portability, one limitation is using it for epiphytic species, or those growing on trees and not from the ground. In the original study¹⁰, one of the flowers sampled was epiphytic. Because the machine is too heavy to hang freely, a stable, elevated base must be made for sampling. Additionally, the machine can either be plugged in to an electrical outlet or battery powered, so if there is prolonged field sampling, there must be.......

Materials

Name	Company	Catalog Number	Comments
Bulkhead Union	Cole-Palmer	UX-06390-10
FEP tubing	Cole-Palmer	UX-06407-60
Gas Chromatography	Hewlett Packard	6890
Glass Wool, Silanized	Sigma-Aldrich	20411
Inlet liner	Agilent	5062-3587
Mass Spectrometer	Hewlett Packard	5973
Reynolds oven bag	Reynolds Consumer Products	Turkey size
Tenax Porous Polymer Adsorbent	Sigma-Aldrich	11982