Chemical composition and seasonality variability of the Spiranthera odoratissima volatile oils leaves

Harvest time explains substantially more variance in yield, essential oil and quality performances of Salvia officinalis than irrigation and putrescine application

Elicitors, irrigation regimes and harvest times influence the content, yield and compound of the essential oil (EO) in Salvia officinalis (sage), through changes in biomass dynamics and biosynthetic pathways. A two-year field experiment was conducted to determine if foliar application of putrescine under optimum and deficit stress conditions would favorably affect EO yield, content and profile of sage harvested in spring and summer. The response of dry weight, EO yield and content, myrcene and borneol concentrations to irrigation regime and putrescine concentration can be expressed by a quadratic model. The maximum dry weight (182.63 g m-2) and EO yield (1.68 g m-2) were predicted under irrigation regimes of 9.06% and 27.75% available soil water depletion (ASWD), respectively. The highest EO content (1.05%) was predicted under 3.04 mM of putrescine. Based on results obtained from GC/MS analyses, 25 compounds (mostly monoterpenes) were identified in the EO of sage. Among EO compounds, α-thujone (54.08%), 1, 8-cineole (17.87%), pinocarvone (14.30%), β-thujone (7.97%) and camphor (8.76%) in turn were the most abundant. The concentration of myrcene was higher in spring than summer under the irrigation regimes of 60% and 80% ASWD. The myrcene concentration reached its maximum (4.53%) under the irrigation regime of 86.5% ASWD. The irrigation regimes of 48.03% and 45.6% ASWD caused the highest borneol concentrations of 1.47% and 1.41% by application of 1.5 mM and 2.25 mM putrescine, respectively. All treatments tested on sage, particularly harvest time, can play an important role in the improvement of EO quality and quantity. Averaged over both years, the irrigation regime of nearly 30% ASWD resulted in the highest EO yield harvested with greater quantity and better quality in summer. The EO content and quality changed slightly with the application of putrescine, without significant effect on yield.

Effects of water-deficit stress and putrescine on performances, photosynthetic gas exchange, and chlorophyll fluorescence parameters of Salvia officinalis in two cutting times

A 2‐year (2017–2018) field experiment was performed to specify if the foliar application of putrescine (PUT) under optimum and water‐deficit stress (WDS) conditions would favorably affect leaf gas exchange, greenness, chlorophyll fluorescence parameters, pigments, sodium (Na), potassium (K), as well as yield and content of the essential oil (EO) relationships in Salvia officinalis L. (sage) in spring (cutting 1) and summer (cutting 2). Based on the results analysis of variance, the effects of WDS, PUT, and cutting time were significant for the dry weight, leaf area index (LAI), EO content, EO yield, chlorophyll (Chl) t, carotenoid, Na, and K of sage. According to regression results, the response of EO content, EO yield, non‐photochemical quenching (NPQ), spad, Chl a, Chl t, K, and K/Na to WDS can be expressed by a quadratic model, indicating that they would attain their maximum in 75.5%, 34.86%, 38.33%, 84.13% 60%, 70%, 50.40%, and 40.28% available soil water depletion (ASWD), respectively. The response of dry weight, LAI, EO content, EO yield, Fv/Fm, spad, ΦpsII, Chl a, Chl b, Chl t, carotenoid, K, and K/Na to PUT can be expressed by a quadratic model, showing that they would attain their most under 0.98, 1.14, 1.34, 1.16, 1.27, 1.18, 1.17, 1.25, 1.17, 1.27, 1.31, 1.21, and 1.19 mM of PUT, respectively. These findings suggest that, probably, the functions and structures of the photosynthetic system were further enhanced with PUT, thereby they can be promoting primary electron transfer in PSII. Also, stomatal and photosynthetic activity improved with increasing K levels with PUT.

Hexane extract from Spiranthera odoratissima A. St.-hil. leaves: chemical composition and its bioactive potential against Candida pathogenic species, Leishmania amazonensis and Xylella fastidiosa

Spiranthera odoratissima A. St.-Hil. (Rutaceae) has been popularly used against abdominal pain and rheumatism. This study aimed at extracting hexane from S. odoratissima (HE-SO) leaves to identify and quantify its volatile compounds by GC-MS and GC-FID and to evaluate its antifungal, antileishmanial and antibacterial activities in vitro. HE-SO exhibited antileishmanial activity against promastigote forms of Leishmania (Leishmania) amazonensis (IC₅₀ = 38.16 µg/mL) and was moderately active against Xylella fastidiosa (MIC = 100 µg/mL). HE-SO also showed remarkable antifungal potential against six strains of Candida species, i. e., C. albicans, C. glabrata, C. parapsilosis, C. krusei, C. tropicalis and C. orthopsilosis. The lowest MIC values were between 31.25 and 250 µg/mL. Spathulenol (20.2%), τ-cadinol (11.7%), α-cadinol (9.4%), caryophyllene oxide (9.2%) and isoaromadendrene epoxide (8.2%) were the major components identified in HE-SO. Therefore, results showed that HE-SO has promising antileishmanial and antifungal actions.