Brazilian Amazon Orchids—Part III: Volatile Constituents of Floral Scents from Five Gongora Species and Their Chemometric and Chemotaxonomic Analysis

Gongora is a neotropical epiphytic orchid found from Mexico to South America, with 11 species recorded in Brazil. Little is known about the aromas produced by the flowers of these orchid species. This study aimed to identify the volatile constituents of the flowers of Gongora histrionica (1), G. jauariensis (1), G. longiracemosa (2), G. minax (1), and G. pleiochroma (2), all of which are found in the Amazon. Gas chromatography-mass spectrometry (GC-MS) was used to analyze the volatile constituents of Gongora. Additionally, multivariate statistical analysis was employed to evaluate the variability of volatile constituents in their floral aromas. The principal constituents (>25%) of Gongora specimens were (Z)-α-bisabolene, terpinen-4-ol, cis-β-elemenone, (E,E)-geranyl linalool, β-bisabolene, (E,E)-α-farnesene, and 1,8-cineole. Based on the identified compounds, the multivariate statistical analysis revealed seven distinct groups for the Gongora volatile concentrates, indicating a significant variability between the studied species. These results contribute to a better understanding of the genus Gongora chemotaxonomy analysis.