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• Phytochemical and morphological surveys were combined in two Rosemary hybrids. • The leaf aroma profiles characterized specifically each hybrid. • The leaf essential oils varied in fresh and dried samples in both hybrids. • The leaf glandular trichomes resulted useful for the discrimination of the hybrids. The profile of volatile organic compounds (VOC), the composition of the essential oils (EOs) and the micromorphology of the leaf trichomes were investigated in two rosemary hybrids, Salvia×mendizabalii (Sagredo ex Rosúa) Roma-Marzio & Galasso (S × m) and Salvia x lavandulacea (de Noé) Roma-Marzio & Galasso (S × l). The phytochemical analysis highlighted the dominance of monoterpene hydrocarbons in both aroma profiles (65.8 % in S × m and 77.9 % in S × l , respectively), although they displayed different main compounds except for α-pinene (28.2 % in S × m and 24.5 % in S × l). In S × m the EOs extracted from both fresh and dried leaves exhibited camphor (29.7 % and 25.9 %, respectively), α-pinene (21.0 % and 18.2 %, respectively) and 1,8-cineole (11.1 % and 13.6 %, respectively) as major compounds. Noteworthy is the occurrence of β-pinene (2.6 %) in the EO dried samples, whereas sabinene and limonene were exclusive of the fresh samples. In S × l the EOs from the fresh and dried leaves shared the same main compounds: camphor (24.0 % and 27.5 %, respectively), myrcene (14.9 % and 14.8 %, respectively) and α-pinene (13.1 % and 12.2 %, respectively). The micro-morphological observations on leaves proved the occurrence of non-glandular dendritic hairs with smooth cuticle in both hybrids. The glandular trichomes include three main morphotypes: peltate, short capitate and medium-long capitate. The peltate and the short capitates are common to both hybrids, however in the peltate the number of the head secreting cells is different, eight in S × m and sixteen in S × l. The medium-long capitate occurs exclusively on the leaf adaxial side of S × m. [ABSTRACT FROM AUTHOR]

Origanum vulgare (oregano) and Leptospermum scoparium (manuka) were traditionally employed as natural remedies for infected wounds and skin injuries where Staphylococcus aureus is mainly involved. The first aim of this study was to investigate oregano and manuka essential oils (EOs) chemical compositions and evaluate their antibacterial activity (MIC, Minimum Inhibitory Concentration) against fourteen S. aureus wild strains. The second aim was to evaluate the antibacterial activities of oregano and manuka EOs mixed in different combination (FIC, Fractional Inhibitory Concentration) with an improved chequerboard technique. This allowed to avoid the usual uncertainty in the determination of MIC and FIC values and to obtain a more precise interpretation of FIC indexes (FICIs). Moreover, FICIs were discussed on the basis of a novel interpretation method to evaluate the synergistic/antagonistic effect of EOs mixtures. The most representative compounds in oregano EO were Carvacrol (65.93%), p -Cymene (9.33%) and γ-Terpinene (5.25%), while in manuka EO were Leptospermone (31.65%), cis -Calamenene (15.93%) and Flavesone (6.92%). EOs presented MIC values ranging from 1:2048 to 1:4096 v/v and FIC values ranging from 0.125 to 1. According to our interpretation, a synergistic effect (34.68%), a commutative effect (15.32%) and an indifferent effect (50.00%) and no antagonistic effect were observed. Conversely, according to two previously proposed FICI interpretation models, 1.80% synergistic effect could be observed and, respectively, 98.20% indifferent effect or 48.20% additive effect and 50.00% indifferent effect. As practical results, oregano and manuka EOs may be an effective alternative to chemotherapic drugs in staphylococcal infections and useful tools to enhance food security. [ABSTRACT FROM AUTHOR]

The aroma fingerprints of seven endemic Sardinian populations of Genista species ( Genista bocchierii , Genista arbusensis , Genista cadasonensis , Genista corsica , Genista morisii , Genista pichisermolliana , Genista sulcitana ) were defined for the first time in order to investigate the relationship between their chemotaxonomic classification and discriminating volatiles. It is the first time that the inter-species compositional variations of non-terpenoidic constituents and target volatiles such as linalool, limonene, 2,6-nonadienal, 2-pentylfuran, ( E )-2-(2-pentenyl)-furan, ß -caryophyllene and caryophyllene oxide were related by Principal Components Analysis to the actual chemotaxonomic classification of the selected Sardinian Genista species. Although they are not considered marketable aromatic plants, these original results have shown the potential role of volatiles not only as new further important chemotaxonomic markers of Genista species, but also as potential ecological factors in the chemodiversity of some endemic Mediterranean Genista or, more in general, in vegetation changes and reforestation processes. [ABSTRACT FROM AUTHOR]

The main constituents of essential oil (EO) of Origanum syriacum L. collected from cultivated and growing wild in Sinai, Egypt were identified and determined by GC–MS. The antimicrobial activity of these essential oils against Gram positive and Gram negative bacterial strains was studied. The antimycotic activity of these EOs was also evaluated against eight fungal strains isolated from different sources. Forty-six compounds were identified in the EO of both samples, dominated by carvacrol in cultivated type. Thymol, γ-terpinene, linalool and 4-terpineol were the most represented constituents in O. syriacum plants collected from wild populations. Both EOs showed antibacterial activity with varying magnitudes, while EO from cultivated O. syriacum showed high antibacterial activity against Staphylococcus aureus with an inhibition zone of 32 ± 4.0 mm. Both EOs showed good antifungal activity against all fungal strains. O. syriacum EO from cultivated plants showed the lowest MIC 0.25 mg/L with Aspergillus fumigates clinical strain isolated either with Aspergillus flavus. [ABSTRACT FROM AUTHOR]

Myrtle-leaved orange, or chinotto, is a Chinese lesser-known citrus, nowadays cultivated in all the Mediterranean area of Italy. Its fruits are traditionally used in the confectionary and beverage industries: the former mainly uses the unripe fruits, while the juice of the ripe ones is the core ingredient of the well-known Italian soft drink "Chinotto". In the present work, the compositions of several accessions of chinotto fruit peel essential oils (EOs) have been analysed by GC-MS: in particular, i) fresh specimens from Savona (Liguria, Italy) at different ripening stages, as well as a dried ripe one; ii) two accessions from Pisa (Tuscany, Italy), of which one native and one transplanted from Savona. A comparison of the analysed samples with literature reported EO compositions has been performed by means of multivariate statistical analysis. The aim was to assess the influence of both the ripening stage and the geographical area of collection on the EO, assessing which factor influenced it the most. The ripening stage influence on the EO composition was found to be less significant compared to the geographical area of growth of the specimens. The statistical analyses, indeed, evidenced a proximity in the compositions obtained from the different ripening stages, whereas greater differences were evidenced for samples at the same ripening phase, but coming from different regions. Image 1 • The influence of provenience and ripening on Chinotto EO composition was evaluated. • The results were compared to published studies to broaden the sampling population. • Analytical methods and chemometrics were coupled to evidence existing patterns. • The most influencing parameter was the geographical area of origin of the specimen. • The ripening stage was less impacting on the EO compositions from the same area. [ABSTRACT FROM AUTHOR]