Essential oils and volatile emission of eight South African species of Helichrysum grown in uniform environmental conditions

Abstract This paper reported for the first time the aroma profile and essential oil composition of eight species of Helichrysum endemic in South Africa but grown in Italy (CREA-Sanremo collection). The volatiles of all the studied Helichrysum were dominated by monoterpene hydrocarbons, except for H. basalticum, where sesquiterpene hydrocarbons was the main class of compounds with β-caryophyllene (13.7%) and α-guaiene (11.9%) as major components. Despite the great diversity of compounds obtained in the volatile emission (more than 130), only four compounds were responsible for at least 34% of the identified fraction. These compounds were: sabinene (16.0%), β-caryophyllene and α-guaiene in H. basalticum; sabinene (57.7%) in H. foetidum; (Z)-β-ocimene (34.6%), tricyclene (16.2%) and myrcene (10.0%) in H. incanatum; myrcene (29.3%), tricyclene (21.5%) and limonene in H. indicum; tricyclene (32.1%) and (E)-3-hexanol acetate (20.1%) in H. montanum; limonene (10.3%), sabinene (8.9%), 1-decene (7.6%) and 1-hexanol (7.0%) in H. mutabile; α- and β-pinene in H. patulum (27.6% and 44.9%, respectively) and α-pinene (36.3%) and α-fanchene(15.6%) in H. setosum. The EOs composition of these species was also different from each other with sesquiterpene compounds as the prevalent class. Valerianol (16.3%, os, in H. basalticum), ledol (16.3%, os, in H. foetidum), β-caryophyllene (11.0% and 13.4%, sh, in H. indicum and H. patulum, respectively), viridiflorol (18.3%, os, in H. montanum) and valerianol (30.1%, os in H. setosum) were found to be the main constituents. It is worthy to highlighting that the H. incarnatum EO showed a similar behaviour to that of the spontaneous emission with a predominance of monoterpene hydrocarbons (60.7% in EO vs 81.4% in VOC), both represented by (Z)-β-ocimene as main constituent

Evaluation of the in vitro antibacterial activity of some essential oils and their blends against Staphylococcus spp. isolated from episodes of sheep mastitis

AbstractStaphylococcus aureus and coagulase-negative staphylococci are among the major causes of mastitis in sheep. The main goal of this research was to determine the in vitro antibacterial activity of several essential oils (EOs, n 30), then five of them were chosen and tested alone and in blends against staphylococci isolates. Five bacteria were isolated from episodes of ovine mastitis (two S. aureus and three S. xylosus). Biochemical and molecular methods were employed to identify the isolates and disk diffusion method was performed to determine their antimicrobial-resistance profile. The relative percentage of the main constituents in the tested essential oils and their blends was detected by GC-EIMS analysis. Antibacterial and bactericidal effectiveness of essential oils and blends were evaluated through minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). All of them showed sensitivity to the used antimicrobials. The EOs with the highest antibacterial activity were those belonging to the Lamiaceae family characterized by high concentrations of thymol, carvacrol and its precursor p-cymene, together with cinnamon EO, rich in cinnamaldehyde. In terms of both MIC and MBC values, the blend composed by Thymus capitatus EO 40%, Cinnamomum zeylanicum EO 20%, Thymus serpyllum EO 20% and Satureja montana EO 20% was found to be the most effective against all the isolates. Some essential oils appear to represent, at least in vitro, a valid tool against ovine mastitis pathogens. Some blends showed a remarkable effectiveness than the single oils, highlighting a synergistic effect in relation to the phytocomplex

Antibacterial and antifungal activity of essential oils against pathogens responsible for otitis externa in dogs and cats

Essential oils (EOs) are recommended by some veterinarians to treat otitis externa in pets, but data about their efficacy in scientific literature are very scant. Methods: Nine commercial EOs, from roman chamomile (Anthemis nobilis L.), star anise (Illicium verum), lavender (Lavandula hybrida), litsea (Litsea cubeba (Lour.) Pers.), basil (Ocimum basilicum L.), oregano (Origanum vulgare L. subsp. hirticum), rosemary (Rosmarinus officinalis L.), clary sage (Salvia sclarea L.), and thyme (Thymus vulgaris L.) were tested against bacterial and fungal pathogens previously isolated from dogs and cats with otitis externa. In particular, the analyses were carried out against Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus pseudointermedius, Aspergillus niger, Aspergillus fumigatus, Aspergillus terreus, Candida albicans, Candida tropicalis, Trichosporon sp., and Rhodotorula sp. Results: O. vulgare and S. sclarea showed superior antibacterial activity, even if not against all the strains. Trichosporon sp., C. albicans, and A. terreus were insensitive to most Eos, while other yeasts and molds showed different degrees of sensitivity. In particular, most fungi were inhibited by O. vulgare and R. officinalis. Conclusions: The obtained results suggest that some EOs could be included in treatment as an alternative therapeutic option in bacterial otitis complicated by fungi, in association with conventional drugs

Activity of selected essential oils on spoiling fungi cultured from Marzolino cheese

Microscopic fungi can be present on a variety of foodstuff, including cheese. They can be responsible for fungal spoilage, causing sensory changes making food unacceptable for human consumption, and posing severe health concerns. Furthermore, some of these organisms are able to resist antimicrobial preservatives provided for by law. Antifungal activity of 15 chemically defined EOs, alone and in mixture, were checked by a microdilution test against isolates of Penicillium funiculosum and Mucor racemosus cultured from rinds of Marzolino, a typical Italian fresh pecorino cheese. Origanum vulgare yielded the lowest MIC values, followed by Salvia sclarea, Ocimum basilicum and Cymbopogon citratus, while Citrus paradisi and Citrus limon were not active. All mixtures showed antifungal activity at lower concentration with respect to MIC values of each EO component, when not in combination. This study is the first to describe the setting up of EOs mixtures to limit spoiling moulds

Structural, optical, and magnetic properties of Zn-doped CoFe2O4CoFe_2O_4 nanoparticles

The effect of Zn-doping in CoFe(2)O(4) nanoparticles (NPs) through chemical co-precipitation route was investigated in term of structural, optical, and magnetic properties. Both XRD and FTIR analyses confirm the formation of cubic spinel phase, where the crystallite size changes with Zn content from 46 to 77 nm. The Scherrer method, Williamson-Hall (W-H) analysis, and size-strain plot method (SSPM) were used to study of crystallite sizes. The TEM results were in good agreement with the results of the SSP method. SEM observations reveal agglomeration of fine spherical-like particles. The optical band gap energy determined from diffuse reflectance spectroscopy (DRS) varies increases from 1.17 to 1.3 eV. Magnetization field loops reveal a ferromagnetic behavior with lower hysteresis loop for higher Zn content. The magnetic properties are remarkably influenced with Zn doping; saturation magnetization (M(s)) increases then decreases while both coercivity (H(C)) and remanent magnetization (M(r)) decrease continuously, which was associated with preferential site occupancy and the change in particle size

In Vitro Antibacterial Activity of Manuka (Leptospermum scoparium J.R. et G. Forst) and winter Savory (Satureja montana L.) Essential Oils and Their Blends against Pathogenic E. coli Isolates from Pigs

Neonatal diarrhoea (ND), post-weaning diarrhoea (PWD) and oedema disease (OD) are among the most important diseases affecting pig farming due to economic losses. Among the main aetiological agents, strains of Escherichia coli are identified as the major responsible pathogens involved. Several strategies have been put in place to prevent these infections and, today, research is increasingly studying alternative methods to antibiotics to reduce the antibiotic resistance phenomenon. Essential oils (EOs) are among the alternative tools that are being investigated. In this study, the in vitro effectiveness of winter savory and manuka essential oils and their mixtures in different proportions against strains of E. coli isolated from episodes of disease in pigs was evaluated. The EOs alone demonstrated slight antibacterial effectiveness, whereas the blends, by virtue of their synergistic action, showed remarkable activity, especially the 70%–30% winter savory–manuka blend, showing itself as a potential tool for prevention and therapy

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

Juniperus oxycedrus leaf essential oil : chemical characterisation and in vitro cytotoxic activity

Cancer is the second leading cause of death globally and was responsible for 8.8 million deaths in 2015. Among the most common type of cancer that kill people were breast, cervical and bold cancers (OMS). The economic impact of cancer is significant and is increasing. The total annual economic cost of cancer in 2010 was estimated at approximately US$ 1.16 trillion (1). Therefore, the resort to the use of the natural product becomes more and more propitious specially in patients that develop multidrug resistance. The use of essential oil for their anticancer activity dated to 1960 (2)(Bagora et al., 2014) Aim: After the chemical characterization of the leaf essential oil from Juniperus ocycedrus (Cupressaceae), the in vitro cytotoxic activity of this oil on MCF7 and K562 was tested using MTT assay.peer-reviewe

Cultivation Substrate Composition Influences Morphology, Volatilome and Essential Oil of Lavandula Angustifolia Mill.

Aromatic plants are commonly produced for ornamental, cosmetic and medicinal purposes. Their morphological traits and the amounts and compositions of the volatile substances and essential oils (EOs) produced can be influenced by several factors, including the cultivation technique. In the present study, the influence of substrate composition on Lavandula angustifolia Mill. production was evaluated. In particular, substrates containing mixes of peat (P), green compost (C) and/or demolition aggregates (A) were tested in the following ratios: 70%:30% v/v, P:C; 70%:30% v/v, P:A; and 40%:30%:30% v/v, P:C:A. The P:C mixture allowed to obtain the best results in terms of survival rate, compactness of the plant and flower production. The P:C:A led to higher yields and better quality of EOs, with higher amounts of linalool, an important compound for medicinal uses. The volatiles and the blooming trend were not affected by the different cultivation substrates. Therefore, substrate composition in pot lavender cultivation can be regulated depending on the final use of the plant, successfully using locally sourced material in addition to peat