Volatolomics of Three South African Helichrysum Species Grown in Pot under Protected Environment.

Helichrysum decorum DC, Helichrysum lepidissimum S. Moore, and Helichrysum umbraculigerum are three species traditionally used in the South African medicine. The present work deals with the investigation of the spontaneous emission and the essential oils obtained from these plants cultivated in open field under uniform conditions. Fractions of the volatile organic compounds of the three species were rich in monoterpene hydrocarbons, representing more than 70% of the total composition. Pinene isomers were the most representative compounds: ß-pinene in H. decorum (53.0%), and α-pinene in H. lepidissimum (67.9%) and H. umbraculigerum (54.8%). These latter two species evidenced an important amount of sesquiterpene hydrocarbons (SH) especially represented by γ-curcumene (H. lepidissimum) and α- and ß-selinene (H. umbraculigerum). On the contrary, in the EOs, sesquiterpenes compounds prevailed, representing more than 64% of the identified fraction to reach more than 82 and 87% in H. umbraculigerum and H. lepidissimum, respectively. Although the chemical classes and their relative abundances were comparable among the three species, the individual compounds of EOs showed large differences. In fact, caryophyllene oxide (26.7%) and γ-curcumene (17.4%) were the main constituents in H. decorum, and H. lepidissimum respectively, while neo-intermedeol (11.2%) and viridiflorol (10.6%) characterized H. umbraculigerum.

Volatiles and Antifungal-Antibacterial-Antiviral Activity of South African Salvia spp. Essential Oils Cultivated in Uniform Conditions.

Spontaneous emissions of S. dentata Aiton and S. scabra Thunb., as well as the essential oil (EO) composition of the cited species, together with S. aurea L., were investigated. The chemical profile of the first two species is reported here for the first time. Moreover, in vitro tests were performed to evaluate the antifungal activity of these EOs on Trichophyton mentagrophytes, Microsporum canis, Aspergillus flavus, Aspergillus niger, and Fusarium solani. Secondly, the EO antibacterial activity against Escherichia coli, Staphylococcus aureus, and Staphylococcus pseudointermedius was examined, and their antiviral efficacy against the H1N1 influenza virus was assessed. Leaf volatile organic compounds (VOCs), as well as the EOs obtained from the arial part of Salvia scabra, were characterized by a high percentage of sesquiterpene hydrocarbons (97.8% and 76.6%, respectively), mostly represented by an equal amount of germacrene D (32.8% and 32.7%, respectively). Both leaf and flower spontaneous emissions of S. dentata, as well as the EO composition, showed a prevalence of monoterpenes divided into a more or less equal amount of hydrocarbon and oxygenated compounds. Interestingly, its EO had a non-negligible percentage of oxygenated sesquiterpenes (29.5%). S. aurea EO, on the contrary, was rich in sesquiterpenes, both hydrocarbons and oxygenated compounds (41.5% and 33.5%, respectively). S. dentata EO showed good efficacy (Minimal Inhibitory Concentration (MIC): 0.5%) against M. canis. The tested EOs were not active against E. coli and S. aureus, whereas a low inhibition of S. dentata EO was observed on S. pseudointermedius (MIC = 10%). Once again, S. dentata EO showed a very good H1N1 inhibition; contrariwise, S. aurea EO was completely inactive against this virus. The low quantity of S. scabra EO made it impossible to test its biological activity. S. dentata EO exhibited interesting new perspectives for medicinal and industrial uses.

Volatilome Analyses and In Vitro Antimicrobial Activity of the Essential Oils from Five South African Helichrysum Species.

Helichrysum genus was used in folk South African medicine to treat various human disorders. As a part of our on-going research addressing the exploitation of South African plants belonging to this genus, five species were investigated for their volatile and antimicrobial activities. The volatile organic compounds (VOCs) and the essential oils (EOs) were analysed by gas chromatography mass spectrometry (GC-MS). Microdilution was the method used for assessing both antimycotic and antibacterial activities, which was also tested by Kirby-Bauer agar disc diffusion. Total monoterpenes (TMs) dominated the VOCs of four species (H. trilineatum (70.6%), H. edwardsii (79.3%), H. cooperi (84.5%), and H. pandurifolium (57.0%)). H. cooperi and H. edwardsii EOs showed the predominance of TMs (68.2% and 84.5%, respectively), while H. pandurifolium and H. trilineatum EOs were characterized by the prevalence of TSs (86.5% and 43.6%, respectively). H. odoratissimum EO evidenced a similar amount of both TMs (49.5%) and TSs (46.4%). Microsporum canis was more sensitive to these EOs. The lowest minimum inhibitory concentration (MIC) was observed with H. pandurifolium and H. edwardsii EOs (0.25%). H. pandurifolium and H. trilineatum had a good effect on Staphylococcus aureus (MIC 5%). These findings open new perspectives for the exploitation of these natural compounds for application in cosmetics and pharmaceutics.

Essential Oil Composition and Volatile Profile of Seven Helichrysum Species Grown in Italy.

Helichrysum genus consists of about 600 species widespread throughout the world, especially in South Africa and in the Mediterranean area. In this study the aroma profile (HS-SPME) and the EO compositions of seven Helichrysum species (H. cymosum, H. odoratissimum, H. petiolare, H. fontanesii, H. saxatile, H. sanguineum, and H. tenax) were evaluated. All the plants were grown in Italy under the same growth conditions. The volatile constituents, particularly monoterpenes, depended by the plant's genotype and ecological adaptation. This study represents the first headspace evaluation on the selected plants and the results evidenced that monoterpenes represented the main class of constituents in five of the seven species analysed (from 59.2% to 95.0%). The higher content in sesquiterpene hydrocarbons was observed in the Mediterranean species of H. sanguineum (68.0%). Only H. saxatile showed relative similar abundance of monoterpenes and sesquiterpene hydrocarbons. The essential oil composition of the majority of examined species are characterised by high percentage of sesquiterpenes (especially ß-caryophyllene and δ-cadinene) ranging from 51.3% to 92.0%, except for H. cymosum, H. tenax, and H. sanguineum leaves where monoterpenes predominated (from 51.7% to 74.7%).

Exploring volatile aroma and non-volatile bioactive compounds diversity in wild populations of rosemary (Salvia rosmarinus Schleid.).

Ninety-five rosemary (Salvia rosmarinus Schleid.) genotypes, representing 24 wild populations, collected in different geographical areas in Italy and then cultivated under homogeneous environmental conditions, were characterised for volatile organic compounds (VOCs) and three main non-volatile phenolic diterpenes (carnosic acid, carnosol) and acids (rosmarinic acid). Cluster analysis of chemical data highlighted the occurrence of three main groups of populations: one with high levels of verbenone, α-pinene, bornyl acetate, carnosic acid and carnosol, a second one with relatively high levels of camphor and a third one with high levels of 1,8-cineole, ß-pinene and sesquiterpenes. This clustering was consistent with geographic origin and previous genetic characterisation of the same populations. Correlation analysis suggested that levels of the key antioxidant carnosic acid were associated to levels of the key aroma compound verbenone. The observed diversity may be exploited in breeding programs to develop lines and designing products with improved flavour quality and functional properties.

Repellent effect of Salvia dorisiana, S. longifolia, and S. sclarea (Lamiaceae) essential oils against the mosquito Aedes albopictus Skuse (Diptera: Culicidae).

Aedes albopictus (Diptera: Culicidae) has been one of the fastest spreading insects over the past 20 years. Its medical importance is due to the aggressive daytime human-biting behavior and the ability to vector many viruses, including dengue, LaCrosse, Eastern Equine encephalitis and West Nile viruses. In this research, the essential oils (EOs) extracted from fresh air dried leaves of Salvia dorisiana, S. longifolia, and S. sclarea (Lamiaceae) were evaluated for their repellent activity against A. albopictus by using the human-bait technique. The EOs chemical composition was also investigated, and EOs were divided in three different profiles on the basis of their chemical composition: EO with large amount of monoterpenes from S. sclarea, EO rich in oxygenated sesquiterpenes from S. dorisiana, and S. longifolia EO characterized by similar percentages of monoterpenes and sesquiterpenes. The efficacy protection from S. dorisiana, S. longifolia, and S. sclarea EOs, at dosages ranging from 0.004 to 0.4 µL cm(-2) of skin, was evaluated during 120 min of observation. Results indicated that S. dorisiana, S. longifolia, and S. sclarea EOs had a significant repellent activity (RD(50) =0.00035, 0.00049, and 0.00101 µL cm(-2), respectively), with differences in repellency rates, as a function of oil, dosage, and observation time. S. dorisiana was the most effective oil: at the two higher dosages, it gave almost complete protection (with a protective efficacy of 90.99% and 95.62%, respectively) for 90 min. The best protection time was achieved with S. dorisiana essential oil. It ranged from 9.2 to 92.4 min. Protection times of S. longifolia and S. sclarea oils ranged from 3.2 to 60 min, and from 3.6 to 64.2 min, respectively. Our findings clearly reveal that these EOs have a good repellent activity against A. albopictus, therefore they can be proposed to improve the efficacy of repellent formulations against the Asian tiger mosquito.

Volatiloma analyses of four South African Helichrysum spp. grown in Italy.

The volatiloma of four Helichrysum species (H. anomalum, H reflexum, H. retortum and H. rugulosum) was analysed here for the first time by GC-MS for a chemotaxonomic contribution to this genus. Sesquiterpene hydrocarbons (SHs) prevailed in the aroma profile (VOCs) of H. reflexum, H. rugulosum and H. anomalum (74.7%, 93.6% and 41.6%, respectively), even though the main compounds were different (ß-caryophyllene, α-humulene and α-copaene, respectively). The VOCs of H. retortum showed a high percentage of aliphatic hydrocarbons (NTs, 77.7%) mainly represented by octyl ether. The essential oil composition of each of H. rugulosum and H. retortum followed the same trend as VOCs related to the main class (SHs and NTs, respectively). In H. reflexum EO, the SHs were replaced by oxygenated sesquiterpenes (OS, 49.0%) with caryophyllene oxide as the main compound, while in H. anomalum the SHs were swapped in NTs (37.3%).

Antimicrobial Activity and Composition of Five Rosmarinus (Now Salvia spp. and Varieties) Essential Oils.

Salvia rosmarinus Spenn. and Salvia jordanii J.B.Walker are aromatic evergreen shrubs belonging to the Lamiaceae family. Their aerial parts have been used since ancient times as natural preservatives. The present study reported the investigation of the chemical profile and the extraction yield of the essential oils (EOs) obtained from the dried aerial parts of four cultivars of Salvia rosmarinus ('Boule'; 'Vicomte de Noailles'; 'Gorizia'; 'Joyce de Baggio') and the species S. jordanii, together with their antibacterial and antifungal activities. The phytochemical investigation evidenced a predominance of oxygenated monoterpenes in all the samples (57.5-77.1%), except in 'Boule', in which the hydrocarbon form prevailed (50.2%). Principal Component Analysis (PCA) of the matrix taxa × compounds showed that nine compounds have a significant discriminating function between the samples. 'Vicomte de Noailles' was characterized by high amounts of camphor and 14-hydroxy-9-epi-(E)-caryophyllene, while 'Gorizia' and Jord differed in their predominance of camphene, borneol, bornyl acetate, and α-humulene. Lastly, 'Boule' and 'Joyce de Baggio' segregated separately and were characterized by high amounts of α-pinene, myrcene, and verbenone. The selected EOs presented a moderate antibacterial activity on the tested bacterial strains and resulted not active on the tested yeast species.

Salvia Spp. Essential Oils against the Arboviruses Vector Aedes albopictus (Diptera: Culicidae): Bioactivity, Composition, and Sensorial Profile-Stage 1.

Mosquito-borne arboviruses diseases cause a substantial public health burden within their expanding range. To date, their control relies on synthetic insecticides and repellents aimed to control the competent mosquito vectors. However, their use is hampered by their high economic, environmental, and human health impacts. Natural products may represent a valid eco-friendly alternative to chemical pesticides to control mosquitoes, and mosquito-borne parasitic diseases. The aim of this work was to combine the chemical and sensorial profiles with the bioactivity data of Salvia spp. essential oils (EOs) to select the most suitable EO to be used as a repellent and insecticide against the invasive mosquito Aedes albopictus (Diptera: Culicidae), vector of pathogens and parasites, and to describe the EOs smell profile. To do this, the EOs of four Salvia species, namely S. dolomitica, S. dorisiana, S. sclarea, and S. somalensis were extracted, chemically analyzed and tested for their bioactivity as larvicides and repellents against Ae. albopictus. Then, the smell profiles of the EOs were described by a panel of assessors. The LC50 of the EOs ranged from 71.08 to 559.77 µL L-1 for S. dorisiana and S. sclarea, respectively. S. sclarea EO showed the highest repellence among the tested EOs against Ae. albopictus females (RD95 = 12.65 nL cm-2), while the most long-lasting, at the dose of 20 nL cm-2, was S. dorisiana (Complete Protection Time = 43.28 ± 3.43 min). S. sclarea EO showed the best smell profile, while S. dolomitica EO the worst one with a high number of off-flavors. Overall, all the EOs, with the exception of the S. dolomitica one, were indicated as suitable for "environmental protection", while S. dorisiana and S. sclarea were indicated as suitable also for "Body care".

Helichrysum araxinum Takht. ex Kirp. grown in Italy: volatiloma composition and in vitro antimicrobial activity.

In the present work the composition of biogenic volatile organic compounds (BVOCs) and the essential oil (EO) of Helichrysum araxinum Takht. ex Kirp. aerial parts, together with the antimicrobial activity, were investigated. The results showed the prevalence of sesquiterpene hydrocarbons in both spontaneous emissions as well as in the EO. The main compounds of BVOCs were γ-curcumene (10.7%), γ-muurolene (9.2%), and ß-selinene (8.5%). This latter constituent also showed a similar amount in the EO and represented the most abundant compounds together with α-selinene (8.0%). It is Interesting to note the same percentage of monoterpene hydrocarbons (MHs) in both the aroma profile and the EO (18.0%) with the same most abundant compounds: ß-pinene (6.3% in BVOCs vs. 5.1% in EO, respectively) and limonene (4.5% in VOCs vs. 4.9% in EO, respectively). With regard to the antimycotic activity, the EO showed to be inactive against the tested strains, while a moderate antibacterial activity was shown against Staphylococcus isolates.

High throughput measure of diversity in cytoplasmic and nuclear traits for unravelling geographic distribution of rosemary.

In the present work, variability of both cytoplasmic and nuclear microsatellite traits was investigated with the aim of characterizing a set of rosemary germplasm resources (Salvia rosmarinus). Most of the materials were collected in Italy and France. High-resolution melting curves were compared each other computing their Euclidean distances and estimating the differences within their principal component as a measure of genetic diversity. Mantel correlation results combined to linear discriminant analysis allowed examined populations to be divided in four principal groups corresponding to four geographic areas, with few interesting and discussed exceptions. As rosemary propagates by seeds coming from insect mediated pollination, steady wild populations can be expected to be in panmictic equilibrium. Gained results confirmed and extended precedent characterization of rosemary genotypes and are compatible with the distribution of other Mediterranean species, as well as with the presence of a glacial refugium in the north-east area of Sardinia previously described. As the officinal use of this aromatic shrub is spreading, characterization and conservation of wild Mediterranean germplasm is gaining strategic importance. A core collection of 100 genotypes was pointed out as suitable for a cheaper biodiversity ex situ preservation as well as for subsequent metabolic and linkage disequilibrium analyses.

Salvia broussonetii Benth.: aroma profile and micromorphological analysis.

The volatile profiles (VOC) and the essential oil (EO) composition from the aerial parts of Salvia broussonetii were analysed. Sesquiterpene hydrocarbons dominate the VOCs from leaves (95.7%) and flowers (67.6%), followed by monoterpene hydrocarbons (2.6 and 29.7%, respectively). The main common compounds are germacrene D, ß-bourbonene, α-pinene, α-copaene and α-gurjunene, even if with divergent relative abundances. In the leaf EOs the sesquiterpenes prevail, even if not overwhelmingly (about 50.0%), followed by monoterpenes (23.0-35.0%) and by minor fractions of diterpene hydrocarbons and non-terpene derivates. The most abundant common compounds across the two sampling periods are α-pinene, ß-pinene, isobornyl acetate, α-gurjenene, germacrene D and bifloratriene. A morphological characterisation of the trichomes responsible for the productivity in terpenes was also performed. Four different morphotypes were observed on the above ground organs of S. brussonetii: peltates and capitates of type II and III resulted the only producers of volatile substances.