Volatile compounds of five mangrove species and parts

Mangrove plants contain a variety of secondary metabolites, which are
important for their survival and adaptation to the coastal environment, as
well as for producing bioactive compounds. To reveal differences in
mangrove volatiles, a GC-MS method was built up and used to analyze and
identify five mangrove species' leaf, root, and stem. The relative
content and type of volatile compounds were counted and compared, and
their pathway enrichment analysis was performed. The results showed that
532 compounds were detected in the leaf, root, and stem parts of five
mangrove species, which were grouped into 18 classes including alcohols,
aldehydes, alkaloids, alkanes, etc. The number of compounds found was from
41 to 86 in each part of five mangrove species, A. corniculatum leaves and
A. marina roots contained a maximum of 86 compounds. 247 compounds were
found in A. corniculatum, 245 in K. candel, and 240 in A. marina. Roots,
stems, and leaves each had 399, 342, and 339 compounds. There were 40
unique compounds in A. corniculatum leaves, and 39 in A. corniculatum
stems. 71 common compounds occurring in more than two species or organ
parts were analyzed by PLS-DA model. Compared with the contents and
compositions of their compounds, A. ilicifolius and B. gymnorrhiza
differed significantly from the other species, while the leaves differed
significantly from the other parts. Unique compounds and common compounds
were found to have a significant difference in composition and
concentration between species and parts based on the results of one-way
analysis of variance, principal component analysis, and hierarchical
clustering analysis. VIP screening and pathway enrichment analysis were
performed on 17 common compounds closely related to mangrove tree species
or parts, and these compounds were involved in metabolic pathways of C10
isoprenoids, C15 isoprenoids, fatty alcohols, etc. These findings might
help in the development of genetic varieties and medicinal utilization of
mangrove plants.