Chemical profile and antifungal potential of essential oils from leaves and flowers of Salvia algeriensis (Desf.): A comparative study

Salvia is a plant genus widely used in folk medicine in the Mediterranean area since antiquity. A large number of Salvia essential oils have been reported against diverse microorganisms. In the current study, chemical composition of essential oils from leaves and flowers of Salvia algeriensis (Desf.) was determined using gas chromatography-electron impact mass spectrometry (GC-EIMS) as well as their antifungal activity against phytopathogenic fungi Alternaria solani and Fusarium oxysporum exploring disk method. The GC-EIMS analysis identified 59 compounds (84.8%) in the essential oil obtained from leaves of S. algeriensis. Its major constituents were benzaldehyde (9.7%), eugenol (8.7%) and phenylethyl alcohol (8.4%). In flowers oil, 34 compounds (92.8%) were detected. The main ones were viridiflorol (71.1%) and globulol (8.6%). The essential oil obtained from leaves exhibited the highest antifungal activity, where the effective dose inhibiting 50% of mycelial fungal (ED50) against A. solani was 0.90 μL mL-1 with minimum inhibitory concentration (MIC) equal to 2 μL mL-1, whereas the ED50 and MIC in F. oxysporum culture was 1.84 μL mL-1 and 3 μL mL-1 respectively. The mycelial inhibition by flowers oil varies from 1.77 μL mL-1 (ED50) with A. solani culture (MIC 6.5 μL mL-1) to the lowest effect recorded (ED50 3.00 μL mL-1 and MIC 9.33 μL mL-1) against F. oxysporum. To our best knowledge, this is the first report on S. algeriensis, their leaves oil can constitute an alternative biocontrol against phytopathogenic fungi commonly controlled by chemical fungicides.

Determination of borneol and other chemical compounds of essential oil of Dryobalanops aromatica exudate from Malaysia

Purpose: To determine borneol and other chemical compounds of essential oil derived from the exudate of Dryobalanops aromatica aromatica in Malaysia. Methods: Exudate was collected from D. aromatica and subjected to fractional distillation to obtain essential oil. Gas chromatography-mass spectrometry (GC-MS) was performed to characterize the composition of the isolated essential oil. Results: Essential oil (7.58 %) was obtained with the highest yield (3.24 %) in the first 2 h of fractional distillation. Thirty compounds which accounted for 97.56 % of total essential oil composition were identified by GC-MS, and they include sesquiterpenes (46.87 %), monoterpenes (31.05 %), oxygenated monoterpenes (16.76 %) and oxygenated sesquiterpenes (2.13 %). Borneol (0.74 %) was also detected in the essential oil. Conclusion: Borneol and other terpenoid compounds are present in the essential oil of the exudate of D. aromatica