Study of Rosemary Peltate Glandular Trichomes Using Combined Morphological and Chemical Approach

Abstract

Rosemary (Rosmarinus officinalis L.) is a member of the Lamiaceae family that is commonly used in herbal teas. Plants from the Lamiaceae family have numerous peltate glandular trichomes (PGTs). These PGTs contain essential oils, which influence the perception of rosemary aroma. In the present study, we used gas chromatography-mass spectrometry (GC-MS) to evaluate the chemical quantities of 10 active odor compounds from rosemary, i.e., camphene, 1,8-cineole, camphor, linalool, borneol, verbenone, carvone, geraniol, bornyl acetate and alpha-pinene. In addition, we used X-ray computed tomography (X-ray CT) to examine the tissue structure of PGTs from the leaves and stems of rosemary plants. We confirmed that PGTs included 3 types of essential oil. Moreover, we clearly demonstrated that individual PGTs have different structures, filled with different types of essential oil. Our findings suggest that combined use of X-ray CT and GC-MS is an effective means of evaluating the qualities of rosemary PGTs and essential oil.

The Effect of Light on Plastid Differentiation, Chlorophyll Biosynthesis, and Essential Oil Composition in Rosemary (Rosmarinus officinalis) Leaves and Cotyledons

“…Further major components were 1.8-cineole, camphor and verbenone. Similar essential oil composition was reported earlier in rosemary leaves (Tucker and Maciarello, 1986;Boix et al, 2011;Affholder et al, 2013;Sagawa et al, 2013;Loussouarn et al, 2017), peltate glandular hairs (Sagawa et al, 2013) or even callus (Boix et al, 2013). However, essential oil composition strongly varies among cultivars (Tucker and Maciarello, 1986) and developmental stages or even during seasons (Lakusic and Slavkovska, 2013).…”

“…This outlines that in addition to their extremely small size, cotyledons are also not suitable sources for conventional therapeutic essential oils from rosemary as they have completely different essential oil composition. High bornyl acetate contents were observed in peltate glandular hairs of leaves and stipules of rosemary in a work in which hot water extraction and SPME-GC/MS was used for quantification (Sagawa et al, 2013). Bornyl acetate is a highly added value compound used as food additive, flavoring agent and also in the perfume and cosmetic industries due to its pine scent.…”

Volatile Organic Compounds of the Glandular Trichomes of Ocimum basilicum and Artifacts during the Distillation of the Leaves

“…Most of previous works concerned the morphology and structure of the glands and involved microscopical observations [15][16][17][18][19]. Only in a few cases the morphological study was accompanied and supported by chemical analyses of secreted oils: in Mentha piperita [20,21], Salvia officinalis [22][23][24], Thymus vulgaris [25], Rosmarinus officinalis [26,27], and Ocimum basilicum [28].…”