Plants were collected in the Inner plain, the Sharon plain and the kava valley.

The major constituent of all three oils was found to be 1,8-cineole (26.4-34.5%) followed by menthone (10.0-16.7%), pulegone (7.0-7.5%), and isomenthone (4.7-7.8%). Despite some differences in the component proportions, the plants of all three populations clearly belong to the same chemotype.

The aerial parts of flowering Mentha pulegium plants (cut at ground level) and individual M. pulegium plants were collected in the summer (July, 2003) from three wild populations located in the Municipality of Laganas, Zakynthos, W. Greece. Location 1 (N 37° 41′ 29″, E 20° 50′ 25″; map datum WGS 84; altitude 3 m; 14/07/03) was close to Keri Beach (Limni Keriou), Location 2 (N 37° 43′ 34″, E 20° 50′ 41″; altitude 3 m; 13/07/03) was near the village of Kalamaki and Location 3 (N 37° 39′ 39″, E 20° 48′ 44″; altitude 160 m; 17/07/03) was near the village of Vasilikos. The three locations are within the mainland limits of the protected area of the National Marine Park of Zakynthos (NATURA 2000 Network, site GR 2210002; 14).

The composition of the inflorescence (I), leaf (L) and stem (S) essential oils of wild Mentha pulegium plants from three populations (1-3) on the island of Zakynthos were examined. Pulegone (32.8 %, S1 to 75.8 %, I3) was the major constituent of all of the oils. The other main constituents were piperitenone (5.1 %, L3 to 35 %, I2), isomenthone (4.3 %, I2 to 28.6 %, L3) and piperitone (0.5 %, I3 to 5.2 %, L2). In total, C-3-oxygenated p-menthane compounds constituted from 73.0 % (S1) to 96.2 % (I2) of the oils. The piperitenone content of the inforescence oils was up to 2.4 (Loc 3) times higher than that of the leaf oils. Correspondingly, the isomenthone content of the leaf oils was up to 4.2 (Loc 2) times higher than that of the inforescence oils. The ratio of the isomenthone:piperitenone content of the oils (n=3) was markedly different for the inforescence (mean 0.31), leaf (mean 2.91) and stem (mean 1.12) oils.

Mentha rotundifolia leaves were collected in the second week of November 2004 in two localities of Algeria (Rouina: altitude 250 m, Miliana: altitude 780 m) within the region of Ain-Defla located in northern Algeria.

Thirty-nine compounds were identified in leaf oil of sample 1 (Rouina, Algeria), the main one being cis-piperitone oxide. Thirty-nine compounds were identified in leaf oil of sample 2 (Miliana, Algeria). The main one being piperitenone oxide.

The aerial parts of flowering Mentha spicata plants (cut at ground level) and individual M. spicata plants were collected in the summer (July, 2003) from three wild populations located in the Municipality of Laganas, Zakynthos, W. Greece. Location 1 (N 37° 39′ 39″, E 20° 48′ 44″; map datum WGS 84; altitude 160 m; 14/07/03) was near the village of Keri, Location 2 (N 37° 41′ 29″, E 20° 50′ 25″; altitude 3 m; 14/07/03) was close to Keri Beach (Limni Keriou) and Location 3 (N 37° 43′ 34″, E 20° 50′ 41″; altitude 35 m; 14/07/03) was near the village of Pandocratoras. The three locations are within the mainland limits of the protected area of the National Marine Park of Zakynthos (NATURA 2000 Network, site GR 2210002; 8).

The main oil constituents were trans-piperitone oxide, piperitenone oxide and 1,8-cineole. On a whole plant basis (aerial parts) the trans-piperitone oxide content ranged from 1.4 % location (Loc 1) to 32.5% (Loc 3) and appeared to have an inverse relationship with the 1,8-cineole content which ranged from 10.8 % (Loc 3) to 37.9 % (Loc 1). 1,8-cineole was the major oil constituent (37.9 %) of M. spicata plants from Loc 1. The major constituent of the inflorescence oils was piperitenone oxide which ranged from 32.4 % (Loc 3) to 46.3 % of the oil (Loc 1). The major constituent of the leaf oils was 1,8-cineole (40.5 %) in plants from Loc 1 and trans-piperitone oxide in plants from Loc 2 (19.8 %) and Loc 3 (33.5 %). This is the first report for wild populations in Greece of a M. spicata oil in which 1,8-cineole is the major constituent. The observed variation in essential oil composition between locations and plant organs in July would not appear to be directly related to the climatic conditions.

The aerial parts of M. biflora collected during November 1993 and June 1994 were used for the investigation.

The major constituents of the oil were neral (25.3-32.2%) and geranial (26.7-41.3%). The oil produced in the winter was found to contain higher amounts of oxygenated monoterpenes than the oil produced in the summer.

S. aucheri var. aucheri was collected in Karaman: Ermenek to Mutt Road on July 19,1995; Salvia aucheri var. canescens was collected in Karaman: Ermenek, Tekecati Valley on July 19,1995.

Eighty components were characterized in the Salvia aucheri var. aucheri oil, with camphor (21.1%), 1, 8-cineole (20.3%), borneol (7.8%), spathulenol (6.3%) and camphene (5.3%) as major constituents. 1, 8-Cineole (25.2%), camphor (17.9%), borneol (10.6%), alpha-pinene (5.4%) and camphene (5.3%) were identified as major constituents among the 88 components characterized in the oil of Salvia aucheri var. canescens.

Aerial parts of both varieties(Salvia euphratica Montbret et Aucher ex Benth. var. euphratica and Salvia euphratica Montbret et Aucher ex Benth. var. leiocalycina) were collected in Malatya, Turkey in June 1999.

Ninety-five compounds in var. euphratica and 94 compounds in var. leiocalycina were characterized representing 93% and 95% of the total components detected, respectively, with 1,8-cineole (13.8% and 15.2%) and myrtenyl acetate (15.9% and 13.9%) as main constituents.

Plant material and isolation procedure: Aerial parts of the plant were collected from two regions, from Kazeroon in southern Iran and Shahr-e-kord in western Iran at the time of flowering in June 2002.

The main components of the oil of S. pilifera collected from Kazeroon, in southern Iran, were spathulenol (15.8%), cis-chrysanthenol (15.3%), beta-caryophyllene (8.4%) and cis-chrysanthenyl acetate (6.9%), while for the plant collected from Shahr-e-kord, in western Iran, they were cis-chrysanthenyl acetate (21.8%), linalool (18.9%), terpinen-4-ol (11.9%) and cis-chrysanthenol (9.2%).

The plants were cultivated in the Botanical Garden of the University of Agriculture, Plovdiv/Bulgaria on meadow-carbonate soil with neutral reaction (pH 7.1-7.2) and were harvested during the flowering period (July and September). The reserves of nitrogen, phosphorus and potassium in the soil (NPK) were: NH⁴⁺ 31.42 mg/kg; NO^3- 16.66 mg/kg; P₂O₅ 12.3 mg/100 g and K₂O 11.4 mg/100 g. Ammonium nitrogen and nitrate nitrogen were extracted from the soil with a 1% solution of KCI and were determined by consecutive distillation on a Parnas-Vagner apparatus. Phosphorus was determined by the Egner-Ream method and potassium was extracted with 2 n HCI and was determined by flame photometry. The plants were grown as seedlings and were planted in a two-row bed 50 × (20 + 20) cm in patches of 5 m². A scheme on the increase was used for the introduction of N, P and K fertilizers. The experiment was carried out as a randomized block modus - 15 variants in 4 replications (6 levels for N and 4 levels for P and K). Phosphorus (triple superphosphate - 50 % active substance) and potassium (potassium sulphate - 50 % active substance) were introduced only once before planting. Nitrogen (the ammonium nitrate - 33 % active substance) was introduced in three portions - during preparing of the soil, during the plants drafting (active vegetation) and at the full bloom.

The highest oil yield was obtained from leaves in July for N4P2K4 (0.63%) and the basic components were piperitenone (29.4%) and piperitone (13.5%). The mineral fertilization had no effect on the oil yield from the flowers. Regardless of the variant, it was found that the flower oils in July were rich in caryophyllene oxide (12.0-48.4%) and piperitenone (3.0-7.0%), while the oil composition in September was different.

Plant materials were collected from the following localities in north western Turkey. A = Trabzon: Caykara, Soganli dag on July 28, 1994; B = Bayburt: Caykara, Mohakambo yaylasi on July 25, 1994; C = Trabzon: Koprubasi, Vizara yaylasi on July 20, 1994.

One hundred and four compounds were identified representing 97.5-99.5% of the total components detected in thymol/carvacrol (50.14/10.67%), thymol/linalool (23.14/20.24%) and linalool/alpha-terpinyl acetate/geraniol (21.55/16.70/11.17%) rich oils.

Aerial parts of the plant were collected from four localities: A = Kirklareli: Karadere in May 1991; B = Kirklareli: Karahamza Village in May 1990; C = Kirklareli: Evciler Village on 13 June 1993; D = Kirklareli: Korukoy on 25 May 1994

The four oils obtained from plants collected in different localities of the same region gave quite different compositions as follows: A: thymol (10.5%), 1,8-cineole (9.96%), p-cymene (9.48%), carvacrol (5.28%); B: beta-caryophyllene (29.50%), carvacrol(20.59%); C: thymol (34.7%), beta-caryophyllene (12.74%), carvacrol (5.24%); D: beta-caryophyllene (56.48%), germacrene D (11.12%), carvacrol (4.85%). Since the identities of the plant materials were checked repeatedly, any misidentification is ruled out. Except for A and C, all the other materials showed beta-caryophyllene as the major constituent. Carvacrol (20.59%) was present in good amount in the oil of B. In A, however, high percentages of 1,8-cineole (10%) and p-cymene (9.5%) were significant. This oil contained only a trace amount of beta-caryophyllene. Four isomeric caryophyllene alcohols were detected in the oil B. The results clearly indicate that the oil of T. striatus var. interruptus has no consistency and we can safely suggest that there are at least three chemotypes, namely thymol/1,8-cineole/p-cymene-type; thymol/beta-caryophyllene-type; and beta-caryophyllene-type, of this species.