Analysis of the Content and Chemical Composition of Essential Oil in the Leaves of Sage (Salvia officinalis L.) cv. 'Bona' in the Second Year of Cultivation, The

Journal of Essential Oil Research: JEOR, Jul/Aug 2006 by Zawislak, Grazyna, Dyduch, Jan

Abstract

The research was conducted in the years 1997-1999. The original material for the research was sage leaves (Salvia officinalis L.) cv. 'Bona', which came from a two-year plantation. A three-year research study proved that the percentage amount of oil in the raw material of sage was related to the harvest time of the crop. It was higher in leaves coming from the second term of crop (middle of September) and ranged from 1.6% to 1.8%. The percentage amount of oil in sage leaves collected in May (first crop) was lower and fluctuated between 0.8% and 1.4%. Qualitative and quantitative analyses of distilled oils were made using GC and GC/MS. The analyses demonstrated the presence of 31 components in the oil. We found that the oil components varied quantitatively, depending on the harvest time. The main components occurring in sage oil were α-thujone (18.4-27.9%), β-thujone (8.0-15.0%), 1,8-cineole (4.0-14.4%) and camphor (11.7-27.0%).

Key Word Index

Salvia officinalis, sage, essential oil composition, α-thujone, β-thujone, 1,8-cineole, camphor.

Introduction

Sage (Salvia officinalis L.) originates from a region near the Mediterranean Sea. Sage is also cultivated in Poland (1). Accordingto Polish Pharmacopoeia V (2), the material of sage is leaves and leaved tops of shoots. It is used as anti-inflammatory, anti-microbial and astringent agent (3). Sage leaves and oil have a strong fragrant and aromatic odor. Extracts of this plant are used in the manufacture of perfumes and cosmetics (4). The oil has a multi-level action and a complex chemical composition (5). The main components appearing in sage oil are α- and β-thujone, and camphor, which along with 1,8-cineole causes its characteristic smell and fragrance (6). The only Polish cultivar of sage is 'Bona', registered in 1989 and introduced into cultivation. This cultivar gives a high yield of the raw material already in the first year of its vegetation (7).

Experimental

Plant material: The research was conducted in the years 1997-1999. The transplants of sage were produced using seeds obtained from Research Institute of Medicinal Plants in Poznan. The only Polish variety of sage (S. officinalis) is 'Bona', registered in 1989 (7). The original material for the research was sage leaves, which came from a two-year plantation. The raw material was collected in two phases: in May (first crop) and in the middle of September (second crop). The amount of oil in air-dried leaves was determined according to Polish Pharmacopoeia V (2).

GC and GC/MS: GC/MS was conducted with a ITS-40 (GC/ITMS - Finnigan MAT, USA) with 30 m x 0.25 mm, DB-5 column (J&W, USA), film thickness 0.25 pm, carrier gas He, injector temperature -280°C. A temperature gradient was applied (35°C for 2 min, then increased by 4°C/min to 280°C).

GC was conducted with UNICAM 610 (Unicam, UK) with DB-5 column (J&W, USA) operated under the same conditions as GC/MS, carrier gas H^sub 2^, FID -220°C. The qualitative analysis was carried out on the basis of MS spectra and it was compared with the spectra of the NIST library (8) and the LIBR (TR) terpenes library provided by Finnigan MAT (9). The compounds identities were confirmed by retention indices from the literature and our own data (10,11). The quantity composition of oils was determined by GC (FID) by assuming that a total of all the particular oils constituted 100%, and correction factors were not used.

Results and Discussion

A three-year research proved that the percentage amount of oil in the raw material of sage is related to the term of its crop. It was higher in leaves coming from the second term of crop ( middle of September) and ranged from 1.6% to 1.8%. The percentage amount of oil in sage leaves collected in May (first crop) was lower and fluctuated between 0.8% and 1.4% (Table I).

The GC/MS analysis demonstrated the presence of Slcomponents in the oil. Percentage composition of sage oil is shown in Table II and Table III, respectively. Twenty-nine components were identified in the oil of sage harvested at vegetative and flowering stage ( 12). Eighty-nine components were identified in sage grown at 100% of full sunlight (13). We found that the oil components varied quantitatively, depending on the harvest time.

The main components occurring in sage oil were α- and β-thujone. The studies proved that the oil obtained from the leaves collected in the second term contained a higher amount of this compound (from 18.4% up to 27.9% of α-thujone and from 8.0% up to 15.0% of β-thujone) than in the first phase (8.2-17.5% of α-thujone, 4.5-12.0% of β-thujone). It is interesting to note the amount of camphor, whose amount in the oil obtained from the leaves collected in May fluctuated from 2.7% to 4.8%, and in the middle of September was between 11.7% and 27.0%.

The sage oil obtained from the leaves collected in the first term also contained significant amounts of 1,8-cineole (15.7-19.4%), β-caryophyllene (8.7-11.6%), viridiflorol (6.2-8.5%) and α-pinene (5.3-5.8%). In the oil obtained from the leaves collected in the second term we found that same of the components were present in smaller amounts: 1,8-cineole (4.0-14.4%), β-caryophyllene (3.4-5,0%), α-pinene (2.5-7.3%), viridiflorol (1.8-5.9%). Moreover, in the composition of the oil, we discovered the presence of borneol and p-cymene. The amount of these two compounds in the oil obtained from the raw material collected in May (first crop) ranged between 3.6-15.6% for borneol and 0.2-0.6% for p-cymene, respectively. The oil obtained from the leaves collected in the middle of September (second crop) contained less bomeol (1.9-2.8%), and the amount of p-cymene fluctuated between 0.1% and 0.6%.