Content Of Α-pinene Research Articles

Chemical Variability of the Leaf Essential Oil of Two Subspecies of Juniperus oxycedrus L. From Northwestern Algeria.

Thirty-seven essential oil samples have been isolated from leaves of individual plants of Juniperus oxycedrus (subspecies oxycedrus and macrocarpa) growing wild in Tlemcen and Aïn Témouchent provinces (Northwestern Algeria). Analysis of eight selected oil samples by GC(RI), GC/MS and 13C NMR, allowed the identification of 88 components that accounted for 84.4-99.5 % of the whole compositions. The 37 compositions were subjected to statistical analysis which suggested the existence of groups and sub-groups I, IIA and IIB. Group I, the most important group with 24 oil samples out of 37, differed from sub-groups IIA and IIB, essentially by the high content of α-pinene (mean value, 69.2 %; SD 6.24). Sub-groups IIA and IIB were differentiated by their content of α-pinene (Mean values, 49.7 % and 27.3 %, respectively) as well as δ-3-carene (10.3 %, sub-group IIA), sabinene and (Z)-6-pentadecen-2-one (8.7 % and 4.9 %, respectively, sub-group IIB).

Diurnal, and seasonal dynamics in essential oil content and composition of cultivated Helichrysum italicum (Roth) G. Don

Helichrysum italicum from the Asteraceae family is a small odorous shrub that is distributed in the Mediterranean region different altitudes. However, the species was not naturally found in the flora of Türkiye. Cultivation interest in H. italicum has grownsince its cosmetic and pharmaceutical usage. In the present study, H. italicum plants (seedlings were obtained from the same source) were cultivated in Hatay (Mediterranean, 149 m altitude) and Uşak (Continental, 906 m altitude) cities of Türkiye. Harvestings were done in the spring and autumn, at three different hours of the day (09.00, 13.00, and 18.00) in both locations. Soil samples were analyzed to determine some soil properties in both locations. Harvested aerial plant samples were evaluated for essential oil content and composition with three replicates. The experimental field soils' pH values were similar, however there were differences in the ratio of soil lime and macro-microelements. The essential oil content varied between 0.29 and 0.59% in all examined variables. Generally, neryl acetate and α-pinene were found as a main component in all essential oils. Neryl acetate contents ranged between 8.07 and 36.66%, while α-pinene content was found between 13.93 and 31.18%. In the spring harvest, harvesting in the evening produced higher neryl acetate in the continental environment, whereas harvesting at any time of day did not affect the amount of neryl acetate in the Mediterranean climate. In the autumn harvest in the Mediterranean environment, the neryl acetate content was higher in the morning harvest, while neryl acetate content in autumn was comparatively low in the continental climate. Examining the seasons has shown that, in a Mediterranean environment, harvest time is not very significant, but in a continental climate, spring harvest could be favored.

Morphological and phenological characteristic, oil yield, quality and economics of Lemon bee balm (Monarda citriodora Cerv. ex-Lag) at diverse environment condition, India

Lemon bee balm (Monarda citriodora Cerv. ex-Lag) is a noble industrial medicinal and aromatic plant species, which is used as digestive, antifungal, anti-inflammatory and menstrual irregularity remedies in traditional medicine. It is a common source of thymol and other active constituents with recognized antimicrobial properties. A multilocation field trial was performed to evaluate essential oil (EO) yield stability, secondary metabolites and economic returns in eight diverse geographical environment conditions (GEC) in India. The secondary metabolites viz., essential oil content and oil yield were found to be highest in tropical and sub-tropical regions. The essential oil content was found to be higher in inflorescence part at all the experimental sites and found to be highest (0.85±0.21%) at BR-JALAUN. The highest EO yield (130.25±3.25 kg ha−1), net return (Rs. 1,22,125.00±245.21 ha−1) and benefit cost (B:C) ratio (2.67±0.17) was recorded at FFDC-KANNAUJ. The thymol content percentage was found to be highest on physiological maturity (>95% flowering) [PM] and on 75% flowering [FS-II] and it began to decline on seed formation stage at all the experimental sites. The significantly highest thymol content percentage was found on PM (86.65±3.91%) and on FS-II (84.21±3.78%) at TBR-JHANSI. On the basis of the gas chromatography and mass spectrophotometry analysis, twenty constituents were isolated. The inflorescence EO contains more thymol than the EO from leaves with stem which in turn was characterized by a higher content of p-cymene, γ-terpinene, carvacrol, α-phellandrene, α-pinene, myrcene, α-terpinene, citral and β-caryophyllene.

Annual variation in yield, chemical composition, antioxidant and antibacterial activity of rockrose (Cistus ladanifer L.) essential oils

The fluctuation in yield, composition, antibacterial and antioxidant activity of the essential oil (EO) of rockrose (Cistus ladanifer L.) obtained from two locations in central Spain was analysed and compared over the course of one year. Fifteen kilograms of C. ladanifer, collected monthly or fortnightly from two sites with different plant age (7 and 12 years), underwent steam-distillation. GC (FID)-MS analyses were done to determine the volatile profile of EOs. Obtained EO yields varied significantly (P < 0.001) throughout the year, ranging between 0.03 and 0.19% w/d.w. (±0.05) with the highest yields (>0.1%) observed from September to February. The younger population exhibited higher EO yields that the older one. Both rockrose populations displayed a high content of α-pinene (40.4–62.0%); the other predominant constituents included allo-aromadendrene + trans-pinocarveol, limonene, bornyl acetate and viridiflorol. The higher EO yields coincided with a higher content of α-pinene and a lower content of the other components. Furthermore, EOs’ antibacterial potential was tested against Bacillus cereus. Only a weak antibacterial potency (512–1024 μg/mL) was revealed, with stronger potency in case of older rockrose population. In vitro antioxidant capacity, evaluated by ORAC method, showed similar results for both populations, with its stronger potential between February and May.

Chemical Variability of the Berry Essential Oil of Two Subspecies of Juniperus Oxycedrus L. from Northwestern Algeria.

The chemical composition of 33 oil samples isolated from the berries of individual trees of two subspecies of Juniperus oxycedrus L., collected in four locations in Tlemcen and Aïn Temouchent provinces, was investigated by GC-FID, GC/MS and 13CNMR. In total, 83 compounds were identified, accounting for 85.9 % to 98.6 % of the total composition. Yields ranged between 0.02 and 0.40 % (w/w). All compositions were submitted to statistical analysis. Combination of hierarchical clustering dendrogram and principal component analysis suggested the existence of two groups, the second group being sub-divided into two sub-groups. Groups and sub-groups were distinguished with respect to their contents of α-pinene, germacrene D, myrcene and, to a lesser extent, of manoyl oxide. The chemical composition of the oils belonging to subsp. oxycedrus was largely dominated by monoterpenes. α-Pinene (23.7-63.2 %) and germacrene D (4.5-25.4 %) were the major components, followed by myrcene (3.1-16.7 %). Conversely, samples oils of subsp. macrocarpa were largely dominated by germacrene D (4.4-30.0 %), followed by a lower content of α-pinene (10.0-24.3 %) and myrcene (1.0-4.3 %) and a significant content of manoyl oxide (4.3-9.9 %).

The monoterpenes as a characteristic marker for pine species distinction: a chemotaxonomic study from the Czech Republic

For the purposes of chemotaxonomic distinction of four pine species Pinus nigra, Pinus ponderosa, Pinus rigida and Pinus sylvestris growing in the suburban landscape of the central part of the Czech Republic, resin extracts from tree trunks, needles and female cones were analysed using gas chromatography-mass spectroscopy. Monoterpenes were shown to be the main terpene fraction of the resins of all studied pine species. On average, they made up 80% of the total terpene content. A characteristic monoterpene for distinguishing pine species was β-pinene, with high levels in P. ponderosa, moderate levels in P. rigida and low levels in P. sylvestris and P. nigra. P. sylvestris contained only trace amount of Δ-3-carene (0.6%) in resins from needles and thus belongs to the α-pinene chemotypic variation. Slight seasonal variability in terpene production was found for resins from needles of P. nigra and P. sylvestris. When comparing European populations according to the monoterpene composition of resins from needles, it can be stated that the α-pinene content increased in the order P. ponderosa < P. rigida < P. nigra < P. sylvestris while the β-pinene content changed in the opposite direction. This statement confirms the terpene biosynthesis uniformity of European pines.

Essential Oils from Azorean Cryptomeria japonica Female Cones at Different Developmental Stages: Variations in the Yields and Chemical Compositions

Cryptomeria japonica (Thunb. ex L.f.) D. Don (Cupressaceae) is widely cultivated in the Azores archipelago (Portugal) for landscaping and timber production, generating a huge amount of biomass residues. Among these, female cones (FC) emerge as a source of particularly valuable essential oils (EOs), namely, as promising broad-spectrum antimicrobial agents. However, phytochemical research on C. japonica FC EOs remains scarce. This study evaluated the EO yields and chemical compositions of immature and mature FC (IFC and MFC) from the same batch of Azorean C. japonica. IFC and MFC EOs, obtained via hydrodistillation, presented different yields (0.72% vs. 1.12% w/w, dry weight), and their composition, determined via gas chromatography/mass spectroscopy, revealed that the monoterpenes class was dominant (51.84% vs. 69.13%), followed by the sesquiterpenes (36.44% vs. 26.28%) and diterpenes (10.96% vs. 3.03%) classes. However, the correspondent oxygen-containing terpenes classes were 1.5–2.0 times higher in IFC. Thus, the maturation process revealed an increase in EO yield and α-pinene content (19.5% vs. 41.3%) but a decrease in other important bioactive terpenes/terpenoids (terpinen-4-ol, bornyl acetate, elemol, γ-eudesmol, phyllocladene, and nezukol) content. In conclusion, IFC and MFC EOs, due to their unique composition, may have differential commercial applications and, consequently, contribute to increasing the commercial potential of C. japonica’s EO industry.

Quality of Nutmeg (Myristica Fragrans Houtt) South Aceh Based on Geographical Conditions

The results of this study found that the quality of nutmeg in South Aceh, namely climate type A with a very wet category, such as Alluvial, Brown Podzolic, Regusol, Grumosol, Organosol, Renzina, Litosol, Rock Outcrops, Podzolic, Rocks, Latosol and Red Yellow Podzolic. The chemical content of the soil, namely pH, N, P, K, C and CEC after analysis meets the criteria in determining quality nutmeg and soil texture that supports producing quality nutmeg oil processing, the dominant temperature is 26°C with dominant land slope <8% indicating South Aceh nutmeg plantations including a flat surface and the highest elevation is occupied by Meukek District with a height of 51 meters above sea level while the lowest is located in West Labuhan Haji District with an altitude of (-9) meters above sea level. The chemical content of nutmeg contains Myristicin with the highest levels being in North Kluet District, namely 41.08%, the lowest is in Tapak Tuan District, namely 16.66%, the highest chemical content of α-pinene is in Labuhan Haji Barat District, namely 7.85%. the lowest was in Tapak Tuan, namely 0.62%, the highest β-pinene was in Pasie Raja District, namely 14.24%, the lowest was in Meukek District, namely 0.56%.

Detection of Mildewed Nutmeg Internal Quality during Storage Using an Electronic Nose Combined with Chemical Profile Analysis.

Internal mildewed nutmeg is difficult to perceive without cutting the nutmeg open and examining it carefully, which poses a significant risk to public health. At present, macroscopic identification and chromatographic analysis are applied to determine whether nutmeg is moldy or not. However, the former relies on a human panel, with the disadvantages of subjectivity and empirical dependence, whilst the latter is generally time-consuming and requires organic solvents. Therefore, it is urgent to develop a rapid and feasible approach for evaluating the quality and predicting mildew in nutmeg. In this study, the quality and odor characteristics of five groups of nutmeg samples with different degrees of mildew were analyzed by using the responses of an electronic nose combined with chemical profiling. The main physicochemical indicators, such as the levels of α-pinene, β-pinene, elemicin, and dehydro-di-isoeugenol, were determined. The results revealed that the contents of α-pinene, β-pinene, and elemicin changed significantly with the extension of storage time. Through the use of an electronic nose and HS-GC-MS technology to assess the overall odor characteristics of nutmeg samples, it was found that the production of volatile organic compounds (VOCs) such as ammonia/organic amines, carbon monoxide, ethanol, and hydrogen sulfide, as well as changes in the terpene and phenylpropene components of the nutmeg itself, may be the material basis for the changes in odor. The accuracy of the qualitative classification model for the degree of mildew in nutmeg was higher than 90% according to the electronic nose data combined with different machine learning algorithms. Quantitative models were established for predicting the contents of the chemical components, and models based on a BP neural network (BPNN), the support vector machine (SVM), and the random forest algorithm (RF) all showed good performance in predicting the concentrations of these chemical components, except for dehydro-di-isoeugenol. The BPNN performed effectively in predicting the storage time of nutmeg on the basis of the E-nose's responses, with an RMSE and R2 of 0.268 and 0.996 for the training set, and 0.317 and 0.993 for the testing set, respectively. The results demonstrated that the responses of the electronic nose (E-nose) had a high correlation with the internal quality of nutmeg. This work proposes a quick and non-destructive evaluation method for the quality of nutmeg, which has high accuracy in discriminating between different degrees of mold in nutmeg and is conducive to early detection and warning of moldy phenomena.

PENGAMBILAN MINYAK TERPENTIN DARI GETAH PINUS DENGAN METODE MICROWAFE ASSISTED HYDRO-DISTILATION (MAHD)

Turpentine oil is the result of distillation of pine tree sap. The main content of turpentine oil is α-pinene which can be used for the synthesis of organic compounds such as paint and carbolic acid. This study aims to study the process of extracting turpentine oil using the Microwave Hydro-Distillation method. In this research studied the effect of time, power and volume of raw materials in the Microwave Hydro-Distillation process. The variables observed in this study were time (30, 40, 50, 60 and 70 minutes), power (150, 300 and 600 Watt) and raw material volume (150 ml). The quality of turpentine oil such as color, specific gravity, and refractive index were tested according to SNI 7633-2011, while the α-pinene content was analyzed using GC-MS. This study produced the highest yield of 28.22% in the extraction of raw materials of 150 mL using 300 and 600 Watts of power for 70 minutes with 85.01% α-pinene, 5.4% 3-carene and 2.27% β-pinene. Turpentine oil has a characteristic clear color from aquadest solvent with a refractive index of 1.465 and a specific gravity of 0.858 g/cm3, while from hexane solvent with a refractive index of 1.471 and a specific gravity of 0.863 g/cm3. The results of the study concluded that microwave energy has great potential to be used as an energy source for the process of extracting turpentine oil from pine resin because it can produce turpentine oil in a short time.

Diversity of the terpene synthesis in the Thuja species – A comparative chemotaxonomic study

Significant within-plant variability in the terpene composition of cypress species growing in the Czech Republic has been demonstrated. In Thuja plicata, α-thujone (44.8%) dominates in the leaves, α-pinene (39.3%) dominates in the tree trunks, and β-phellandrene (50.1%) dominates in the female cones. In Thuja occidentalis, beyerene (38.4%) dominates in the leaves, α-pinene (64.9%) in the tree trunks, and β-phellandrene (25.5%) in the female cones. In the case of Platycladus orientalis, α-pinene (37.6%–69.6%) dominates both in the leaves and in the female cones, and cedrol (34.1%) dominates in the tree trunks. As regards the terpene profiles, in the tree trunks, T. plicata and T. occidentalis show a slight proximity due to their similar content of α-pinene and totarol, on the other hand, in the female cones, all three studied species show a slight proximity due to their similar content of β-phellandrene. A significant seasonal trend is proven in the β-phellandrene, limonene, rimuene, α-pinene, β-pinene, and beyerene production in T. plicata leaves. The results of terpene profiles from the leaves have been compared with the available literature data using Principle Component Analysis. It can be stated that, with slight variations, the synthesis of the key terpenes among T. plicata populations is quite uniform. In T. occidentalis populations, too, the biosynthesis of key terpenes is uniform, except in the case of T. occidentalis growing in the Czech Republic. Among P. orientalis populations, the synthesis of key terpene α-pinene is very variable. Although there is strong genetic control, also the Δ-3-carene content is not stable among populations.

Seasonal Influence on Volatile Composition of Psidium friedrichsthalianum Leaves, Sampled in the Brazilian Amazon

Psidium friedrichsthalianum (Myrtaceae) is a small tree with antioxidant activity in its fruits and antimicrobial activity in its leaves and thin branches. The present study analyzed the seasonal variability in the yield and essential oil composition of a P. friedrichsthalianum population in Belém, Brazil. Essential oils were obtained by hydrodistillation and analyzed by gas chromatography (GC) coupled to mass spectrometer (MS) and flame ionization detector (FID). Chemometric analyses were carried out to verify the climatic influence on the production and composition of the essential oil. The average oil yield in the dry season (August–February) was 0.5 ± 0.0%, and in the rainy season (March–May), it was 0.8 ± 0.0%, with statistical differentiation. There was a moderate correlation between oil yield and the collection area’s relative humidity (r = 0.63). The PCA and HCA analyses did not show differentiation between the P. friedrichsthalianum oil samples during the dry and rainy seasons. However, the class of monoterpene hydrocarbons presented a negative correlation with temperature (r = −0.81) and humidity (−0.80) of the sampled area. In the PCA and HCA studies, the samples were classified into three groups: Group I (leaf oils) was characterized by a higher content of α-pinene (6.3–18.0%), β-elemene (9.9–14.8%), caryophyllene oxide (4.3–16.3%), and β-pinene (4.8–13.4%). Group II (leaf oils) was defined by a higher content of selin-11-en-4-α-ol (4.6–15.6%), β-elemene (9.9–14.8%), α-pinene (6.3–18.0%), and E-caryophyllene (3.1–8.7%). Group III (fruits volatile concentrate) was characterized by a higher content of α-pinene (17.6%), α-terpineol (13.7%), and selin-11-en-4-α-ol (10.0%). There was significant seasonal variability in P. friedrichsthalianum, whose responses are directly linked to abiotic factors such as precipitation, insolation, humidity, and temperature.

Study on Production Technology and Volatile Flavor Analysis of Fragrance Zanthoxylum Seasoning Oil.

Dried green pepper and first-grade extracted soybean oil were selected as raw materials to study the effect of the Maillard reaction and cold-pressed compound on the quality of Zanthoxylum seasoning oil and its aroma-enhancing effect. The results showed that the optimal technology was as follows: the ratio of material to liquid was 1:5, the heating temperature was 110 °C, the reaction time was 25 or 30 min, and the addition of reducing sugar was 2%. The optimum ratio of fragrant Zanthoxylum seasoning oil was 1:7 for cold pressing oil and hot dipping oil. Compared with Zanthoxylum seasoning oil, it is based on the Maillard reaction and had a more intense and persistent aroma. The taste of fragrant Zanthoxylum seasoning oil was the best of the three blended oils. The possible types of volatile flavor compounds in the three kinds of Zanthoxylum seasoning oils detected by Heracles II ultra-fast gas phase electronic nose were, respectively, 16, 19, and 15. Among the three kinds of Zanthoxylum seasoning oils, the content of limonene, linalool, Eucalyptol, n-pentane α-Pinene, myrcene, and phellandrene was more abundant, which indicated that olefins and alcohols contributed more to the overall flavor of the three kinds of Zanthoxylum seasoning oils.

The effect of Lavandula Coronopifolia essential oil on the biophysical properties of desensitization and deactivation gating currents in ionotropic receptors

The rising incidence of cancer and the lack of effective therapeutic interventions for many neurological illnesses like Alzheimer's and epilepsy has prompted us to investigate the composition and effects of the Lavandula coronopifolia oil from Palestine on cancer cells and AMPA receptor subunits in the brain due to the vast range of beneficial properties of Lavandula coronopifolia essential oil (EO). GC/MS was used to analyze L. coronopifolia's EO chemistry. EO's cytotoxicity and biophysical effects on AMPA receptors were investigated using MTS and electrophysiological techniques. The GC–MS results revealed that L. coronopifolia EO has a high content of eucalyptol (77.23%), β-pinene (6.93%), and α-pinene (4.95%). The EO showed more significant antiproliferative selectivity activities against HepG2 cancer cell lines than HEK293T cell lines with IC50 values of 58.51 and 133.22 µg/mL, respectively. The EO of L. coronopifolia affected AMPA receptor kinetics (desensitization and deactivation) and preferred homomeric GluA1 and heteromeric GluA1/A2 receptors. These findings indicate the potential therapeutic use of L. coronopifolia EO in the selective treatment of HepG2 cancer cell lines and neurodegenerative diseases.

Chemotaxonomic Variation in Volatile Component Contents in Ancient Platycladus orientalis Leaves with Different Tree Ages in Huangdi Mausoleum.

To gain insight into the differences in the composition and volatile components content in ancient Platycladus orientalis leaves with different tree ages in Huangdi Mausoleum, the volatile components were identified by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) method. The volatile components were statistically analyzed by orthogonal partial least squares discriminant analysis and hierarchical cluster analysis, and the characteristic volatile components were screened. The results exhibited that a total of 72 volatile components were isolated and identified in 19 ancient Platycladus orientalis leaves with different tree ages, and 14 common volatile components were screened. Among them, the contents of α-pinene (6.40-16.76%), sabinene (1.11-7.29%), 3-carene (1.14-15.12%), terpinolene (2.17-4.95%), caryophyllene (8.04-13.53%), α-caryophyllene (7.34-14.41%), germacrene D (5.27-12.13%), (+)-Cedrol (2.34-11.30%) and α-terpinyl acetate (1.29-25.68%) were relatively higher (>1%), accounting for 83.40-87.61% of the total volatile components. Nineteen ancient Platycladus orientalis trees were clustered into three groups through the HCA method based on the 14 common volatile components content. Combined with the results of OPLS-DA analysis, (+)-cedrol, germacrene D, α-caryophyllene, α-terpinyl acetate, caryophyllene, β-myrcene, β-elemene and epiglobulol were the differential volatile components to distinguish ancient Platycladus orientalis with different tree ages. The results revealed that the composition of the volatile components in ancient Platycladus orientalis leaves with different tree ages was different, showing different aroma characteristics, which provided a theoretical reference for the differential development and application of volatile components in ancient Platycladus orientalis leaves.

Screening of Rosemary Essential Oils with Different Phytochemicals for Antioxidant Capacity, Keratinocyte Cytotoxicity, and Anti-Proliferative Activity.

Nowadays, the demand for rosemary essential oils (REOs) in the cosmetic, food, and pharmaceutical industries is increasing, and the abundant germplasm resources of rosemary provide more possibilities for functional applications. The REOs from six cultivars were selected to evaluate and compare their bioactivities. REOs have good cellular antioxidant activity in scavenging reactive oxygen species, and the technology for order preference by similarity to an ideal solution (TOPSIS)-random forest multivariate model indicated that 'Dutch Mill' REO has the best antioxidant activity, which is closely related to its verbenone content. In addition, α-pinene-dominant REOs are more toxic to human keratinocytes, which is closely related to the content of α-pinene, as revealed by multivariate analyses. Moreover, anti-proliferative assays on six cancer cell lines showed that all REOs have a higher anti-proliferative ability against human pancreatic cancer cell line SW1990 and gastric epithelial cell line NCI-N87. Among them, 'Miss Jessopp's Upright' and 'Blue Lagoon' REOs exhibit more prominent anti-proliferative activity. Our study provides a reference value for exploring the application potential of different REOs by evaluating their differences in chemical composition and bioactivity.

Feeding Preferences and Responses of Monochamus saltuarius to Volatile Components of Host Pine Trees.

Simple SummaryBursaphelenchus xylophilus causes pine wilt disease, which is one of the most devastating forest diseases in the world. However, B. xylophilus cannot spread naturally and must be carried by vector insects from infested trees to healthy ones. Monochamus saltuarius is a B. xylophilus vector that has caused massive pine tree mortality in Japan, South Korea, and China’s middle temperate zone. In China, there have been only a few reports of this species. The feeding preference of M. saltuarius on different host pine trees was determined, and the volatile components of the host pine trees were analyzed. Furthermore, the responses of M. saltuarius to different host volatiles were determined, and the correlation between M. saltuarius preference and host pine tree volatiles was investigated. This study will serve as a reference for the development and application of M. saltuarius attractants, which will aid in the control of M. saltuarius and pine wilt disease.Monochamus saltuarius is a vector of Bursaphelenchus xylophilus and has caused massive mortality in pine trees in Japan, South Korea, and the middle temperate zone of China. In this study, the feeding preferences of M. saltuarius to four common host pine species in the middle temperate zone of China were investigated in a laboratory. The volatiles of the four host pine species were sampled and analyzed by gas chromatography and mass spectrometry. The responses of M. saltuarius to host pine tree volatiles were measured using a four-arm olfactometer. The results showed that: (1) the preference of M. saltuarius for Pine tabulaeformis was significantly higher than the other ones. (2) The composition and content of the volatiles of the four tested host pine twigs were different, and the relative content of α-pinene was the highest. (3) M. saltuarius was highly sensitive to α-pinene, β-pinene, limonene, and 3-carene, and the attracting effect was enhanced by the mixture of volatile components. This study provides a reference for the development and application of attractants for M. saltuarius. Our results would be helpful in controlling M. saltuarius and pine wilt disease.

Effects of foliar zinc applications on some yield parameters and essential oil constituents of the mastic tree (Pistacia lentiscus var. chia Duham.)

Mastic tree (Pistacia lentiscus var. chia Duham.) is an important medicinal aromatic plant which is being cultivated without any regular fertilization generally. Foliar Zn applications have great importance for many commercial plant species because of their important role in metabolic activities. In this study, the effects of foliar ZnSO4 sprayings (0, 0.2, 0.4, 0.8%) applied at 50% and 100% leafing stages, on some yield parameters and essential oil composition of mastic tree were assessed. A field experiment was carried out for two consecutive years at Ege University, Turkey. Mastic resin yield was more than doubled with 0.8% Zn particularly in the second year. The highest leaf Zn content was measured as 187.8 mg l−1 with 0.8% zinc spraying while it was 35.4 mg l−1 in unsprayed trees at 100% leafing in the first year. Leaf essential oil and α-tocopherol contents were not significantly influenced by different Zn levels and leafing stages in both years. As for the major essential oil constituents, β-myrcene (62.4%), germacrene-D (14.3%), α-terpinenyl acetate (5.52%), t-caryophyllene (2.1%) and α-pinene (1.4%) were determined. Zinc sprayings increased the β-myrcene, germacrene-D and α-pinene contents particularly at 100% leafing in the first year. In mastic tree two consecutive applications of Zn seems to be necessary for reaching to desirable leaf Zn contents. Application of 0.8% Zn or more would be proper to increase the contents of most parameters assessed.

Mentha aquatica L. Populations from the Hyrcanian Hotspot: Volatile Oil Profiles and Morphological Diversity

Mentha aquatica L. (Lamiaceae) is found in different parts of Iran. Its essential oil and preparations regulate bile function and are used as a stomach tonic and disinfectant. This study investigates the morphological and essential oil diversity of M. aquatica populations from the Hyrcanian hotspot of Iran. Plant samples were collected from Gilan, Golestan, and Mazandaran provinces in the Caspian Region for analysis. The results showed significant differences among the studied ecotypes for the stem diameter, collar diameter, number of inflorescences, length and width of inflorescence, sepal diameter, sepal length, and secondary stem length number. Principal component analysis showed that the first seven principal components explained 90.6% of the total variation. Moreover, essential oil concentration varied widely from 1.13% for a sample from Behshahr-Mazandaran, down to 0.27% for one from Abbas abad-Mazandaran. GC–MS analysis identified 29 constituents that accounted for 91% of the total essential oil. The main components of the essential oil were menthofuran (13.21–52.46%), 1,8-cineole (12.42–25.55%), (E)-caryophyllene (3.18–15.43%), viridiflorol (1.04–11.16%), germacrene D (1.70–8.29%), caryophyllene oxide (0.51–4.96%), neryl acetate (1.11–4.95%), p-cymene (1.55–4.77%), and β-pinene (1.7–3.45%). Overall, meaningful diversity was recorded among the populations; Rahimabad-Gilan and Behshahr-Mazandaran would be reliable selections for the food and pharmaceutical industries due to their higher yields and content of α-pinene, 1, 8-cineole, menthofuran, viridiflorol, and β-caryophyllene. Further evaluation of populations from diverse habitats is needed to guide future breeding programs.

Evolution of Phytochemical Variation in Myrtle (Myrtus communis L.) Organs during Different Phenological Stages

Myrtle (Myrtus communis L.) is an important medicinal plant, of which all parts have pharmaceutical and nutritional applications and which is distributed throughout the southwest regions of Iran. The aerial parts of myrtle were collected at different phenological stages (vegetative, flowering, unripe fruit and ripening fruit stages, after the fully mature fruit dispersal stage) from Fars Province of Iran and were analyzed with GC–FID and GC–MS. All the data were submitted to multivariate statistical analysis, showing many differences among the various plant parts and their phenological stages. Monoterpene hydrocarbons (18.9–50.5%) and oxygenated monoterpenes (38.2–72.4%) were the most abundant class in the volatile emissions, with α-pinene, 1,8-cineole, limonene, linalool, α-terpineol, linalyl acetate and geranyl acetate being the main constituents in the majority of the examined samples. α-Pinene content ranged from 8.88% at the after fully mature fruit dispersal stage (leaves) to 32.84% at the flowering stage in the leaves. Limonene, which is the dominant component at the flowering stage, was 23.97% in the flowers, while the limonene amount was 0.14–1.42% at other harvest stages. The greatest 1,8-cineole amount was obtained prior to flowering, 45.98%, while the lowest amount was obtained at the flowering stage, in the flowers. The total phenol and flavonoid contents varied between different myrtle parts: the highest total phenol and flavonoid contents were obtained for the extract made of the before-flowering stage in leaves (66.52 mg GAE/g and 7.49 mg QE/g extracts). Overall, the study indicated that collecting myrtle at the vegetative and flowering stages, especially the leaves organs, would be of considerable importance.