Yield and Composition of the Essential oil of Tetradenia riparia (Hochst) Codd (Lamiaceae) Cultivated Under Different Shading Levels

Abstract

Light has direct influence on growth and development by altering the morphophysiology of the plant and the content and composition of secondary metabolites. The present study aimed to evaluate the yield and composition of the essential oil of Tetradenia riparia cultivated under different shading levels. Plants were propagated by cuttings and cultivated either under full sunlight and in environment completely covered by black polyethylene sheeting to obtain shading levels of 30%, 50%, and 80%. Plants were grown under experimental conditions for 150 days. The essential oil was extracted from fresh leaves in triplicate for each treatment through steam distillation with a modified Clevenger apparatus. The components of the essential oil were identified using a gas chromatograph coupled with a mass spectrometer (GC/MS), and compared to retention indices and authentic mass. The largest yields of essential oil came from plants cultivated under 30% and 50% shading, followed by plants cultiveted under full sunlight and under 80% shading. The main component found was the sesquiterpene hydrocarbon 14-hydroxy-9-epi-(E)-caryophyllene. Some components, such as verbenone, were only found in the treatment under full sunlight, while numerous others were exclusive to the different shading treatments. The yield and chemical composition of the essential oil of T. riparia is influenced by the level of shading.

Effect of shading and nitrogen fertilization on nitrogen metabolism, essential oil content and antimicrobial activity of Achillea millefolium

“…The yields of essential oils from shaded leaves were higher than those yields of unshaded plants. Similar results were observed in Tetradenia riparia grown with 50% shading (Araujo, Melo, Paula, Alves, & Portes, 2018). Essential oil production is usually associated with higher irradiance levels, as demonstrated in studies with peppermint (Mentha piperita; Costa et al, 2014) and basil (Ocimum basilicum; Paulus, Valmorbida, Ferreira, Zorzzi, & Nava, 2016).…”

“…Essential oil production is usually associated with higher irradiance levels, as demonstrated in studies with peppermint (Mentha piperita; Costa et al, 2014) and basil (Ocimum basilicum; Paulus, Valmorbida, Ferreira, Zorzzi, & Nava, 2016). However, the excess in light can cause photoinhibition in some species of plants, and consequently, decrease essential oil yield (Araujo et al, 2018). This suggests that the effects of shading may be species-specific.…”

Bioassay-guided isolation of antibacterial compounds from the leaves of Tetradenia riparia with potential bactericidal effects on food-borne pathogens

“…the main components are: α-terpineol (22.6%), fenchone (13.6%), β-fenchyl alcohol (10.7%), βcaryophyllene (7.9%) and perillyl alcohol (6.0%) (Campbell et al, 1997); other researchers found that 14-hydroxy-9-epi-(E)-caryophyllene is the main component (16.48%) (Araújo et al, 2018).…”

“…However, the major constituents vary between publications, and depend on seasonal variability, geographic location (Gazim et al,, 2010;Melo et al,, 2015;Baldin et al,, 2018) and shading (Araújo et al, 2018). Although there are several reports on the antimicrobial activity of T. riparia, most deal with essential oils, while the leaves are most extensively used in traditional practice.…”

Ethnomedicinal, Phytochemical and Pharmacological Investigations of Tetradenia riparia (Hochst.) Codd (Lamiaceae)

“…However, the concentration of these terpenoids varies according to factors such as the location of the crop implantation, climate, altitude, soil, and collection time. Therefore, we reviewed the literature to compare the chemical composition of T. riparia essential oil from different locations: Africa (South Africa and Kenya) ( Campbell et al, 1997 ; Omolo et al, 2004 ), South America (Brazil) ( Godoy et al, 1999 ; Gazim et al, 2011 and, 2014 ; Araújo et al, 2018 ), and North America (Poplarville, MI, United States) ( Blythe et al, 2020 ); and the chemical identification of the essential oil is shown in Table 3 and Figure 5 .…”