Investigation of the effectiveness of Syzygium aromaticum, Lavandula angustifolia and Geranium robertianum essential oils in the treatment of acute external otitis: a comparative trial with ciprofloxacin

Chemical compositions of Eucalyptus sp. Essential oils and the evaluation of their combinations as a promising treatment against ear bacterial infections

BACKGROUND

The chemical composition and biological activities of Eucalyptus essential oils (EOs) have been documented in numerous studies against multiple infectious diseases. The antibacterial activity of individual Eucalyptus EOs against strains that cause ear infections was investigated in our previous study. The study's antibacterial activity was promising, which prompted us to explore this activity further with EO blends.

METHODS

We tested 15 combinations (9 binary combinations and 6 combinations of binary combinations) of Eucalyptus EOs extracted by hydrodistillation from eight Tunisian Eucalyptus species dried leaves against six bacterial strains responsible for ear infections: three bacterial isolates (Haemophilus influenzae, Haemophilus parainfluenzae, and Klebsiella pneumoniae) and three reference bacteria strains (Pseudomonas aeruginosa, ATTC 9027; Staphylococcus aureus, ATCC 6538; and Escherichia coli, ATCC 8739). The EOs were analyzed using GC/FID and GC/MS. The major compounds, as well as all values obtained from the bacterial growth inhibition assay, were utilized for statistical analysis.

RESULTS

The antibacterial activity of the EO blends exhibited significant variation within Eucalyptus species, bacterial strains, and the applied methods. Principal component analysis (PCA) and hierarchical cluster analysis (HCA), based on the diameters of the inhibition zone, facilitated the identification of two major groups and ten subgroups based on the level of antibacterial activity. The highest antibacterial activity was observed for the mixture of EOs extracted from E. panctata, E. accedens, and E. cladoclayx (paac) as well as E. panctata, E. wandoo, E. accedens, and E. cladoclayx (pwac) using the disc diffusion method. Additionally, significant activity was noted with EOs extracted from E. panctata, E. wandoo (pw) and E. panctata, E. accedens (pa) using the broth microdilution method.

CONCLUSION

Our findings suggest that certain EO combinations (paac, pwac, pw, and pa) could be considered as potential alternative treatment for ear infections due to their demonstrated highly promising antibacterial activities.

Antibiotics versus non-antibiotic treatments for acute otitis externa: A systematic review and meta-analysis

BACKGROUND

Otitis externa is a condition causing inflammation of the outer ear canal, which presents with itching, discharge and pain. Most cases of acute otitis externa are caused by bacterial infection and are thus treated with antibiotics. This systematic review and meta-analysis of randomised controlled trials aims to assess the effectiveness of topical non-antibiotic treatments compared to topical antibiotic treatment for the treatment of acute otitis externa.

METHODS

Systematic review and meta-analysis databases searched: Cochrane Library including ClinicalTrials.gov; MEDLINE; World Health Organisation International Clinical Trials Registry Platform and Web of Science to identify randomised clinical trials evaluating topical antibiotics and topical non-antibiotic agents in adults and children with acute otitis externa. Non-antibiotic therapeutics for comparison with topical antibiotics included antiseptics, steroids, non-pharmaceuticals and astringents.

RESULTS

Seventeen trials were eligible for inclusion, with 10 combined in meta-analysis. Data could be pooled comparing antiseptic and steroid monotherapies with topical antibiotic agents. There were no significant differences in cure rates in any pairwise comparisons. Individually, the majority of studies favoured topical antiseptics or steroids over antibiotics, however these differences were not significant when pooled in meta-analysis.

CONCLUSION

Antiseptic, steroid and antibiotic monotherapies are all effective for the management of acute otitis externa. There is insufficient evidence to suggest that topical antiseptic or steroid agents are superior or inferior to topical antibiotics.

Perspectives of Italian Physicians and Patients in the Treatment of Otitis Externa: A Real-Life Study

(1) Background: Otitis externa (OE) is a common inflammatory disease of the external ear canal. Given the numerous manifestations of OE, the high rate of recurrence of the disease, as well as the emergence of resistance to antibiotics, therapeutic strategies are numerous and still not well standardized. The aim of this study was to investigate the patient journey of Italian patients suffering from OE, paying greater attention to new therapeutic options. (2) Methods: We conducted a national survey to evaluate the characteristics of patients affected by OE and to analyze the most-prescribed treatments. (3) Results: OE is a common, often relapsing disease that has several clinical manifestations. Prior to observation, the combination of corticosteroids and topical antibiotics was the most common therapeutic strategy. At the time of observation, new liposomal ozone-based preparations were the most-prescribed treatment. (4) Conclusions: This multi-center study investigated key aspects of the OE patient journey, highlighting the growing problem of antibiotic resistance. Restoring a correct ear microbiome is the therapeutic goal. In this context, new liposomal ozone-based drugs represent a promising therapeutic strategy.

Protective effects of lavender oil on sepsis-induced acute lung injury via regulation of the NF-κB pathway

CONTEXT

Lavender oil (Lav) from Lavandula angustifolia L. (Lamiacease) exhibits antioxidative and anti-inflammatory properties against various diseases.

OBJECTIVE

The study explores the effect of Lav pre-treatment on sepsis-induced acute lung injury (ALI).

MATERIALS AND METHODS

Sprague-Dawley rats were assigned into Sham, caecal ligation and puncture (CLP), CLP + Lav (200, 400, and 800 mg/kg) groups. Lav was administered by gavage, once a day, for 7 days. Histological analysis was performed using haematoxylin and eosin staining. Cytokine and nitrite levels were detected by enzyme-linked immunosorbent assay kits and Griess reagent. Gene and protein expression were tested by quantitative real-time polymerase chain reaction and western blot.

RESULTS

The levels of tumour necrosis factor-α (BALF: 64%, serum: 59%), interleukin (IL)-1β (BALF: 63%, serum: 66%) and IL-6 (BALF: 54%, serum: 59%), and nitrite (40%) and inducible nitric oxide synthase (51%), and the level of myeloperoxidase (66%) and malondialdehyde (59%), and cleaved-caspase 3 (84%) and Bax expression (74%) induced by CLP were decreased when given Lav. Additionally, the level of superoxide dismutase (211%) and glutathione (139%), and the expression of Bcl-2 (980%) induced by CLP were increased when given Lav. The increased p-nuclear factor (NF)-κB/NF-κB (72%) and p-inhibitor of κBα (IκBα)/IκBα (77%) induced by CLP could be reversed by Lav.

DISCUSSION AND CONCLUSIONS

Lav pre-treatment might protect rats from sepsis-induced ALI via deactivation of the NF-κB pathway. Our research demonstrated the regulatory mechanisms of Lav in sepsis-induced ALI and can provide a theoretical basis for the use of Lav in the treatment of sepsis-induced ALI.

A randomized controlled trial of combination of peppermint, lavender, and turmeric oil for antipruritic agent in pregnant women

BACKGROUND Pruritus is the most common dermatological complaint that occurs during pregnancy, which is around 14–20%. No research related to herbal products to reduce some of the characteristics of pruritus at once has been conducted. This study aimed to assess the effect of blending oil to reduce pruritus based on visual analog scale (VAS). METHODS This was a single-blind, randomized clinical trial that included 57 pregnant women who were at 25–38 weeks of gestation, had a pruritus during pregnancy, a single pregnancy, a level I and II pruritus and a moderate to severe pruritus based on VAS. Pruritus scores were measured using VAS in both the treatment and control groups. The treatment and control groups applied blending oil and placebo, respectively, twice a day after bathing for 2 weeks. Mann–Whitney U, paired t, and chi-square tests were used for the analysis. RESULTS Pruritus reduction in pregnant women who received blending oil was higher than those using placebo (61.08% versus 12.41%, p<0.05). 83% of subjects using blending oils had a reduction of pruritus by >25 mm. Pregnant women who used placebo had a six times greater risk of experiencing pruritus than those who used blending oil (RR = 5.8, 95% CI = 2.613–12.874). CONCLUSIONS Blending oil can be used topically to treat a pruritus in pregnant women.

Dentin erosion preventive effects of various plant extracts: An in vitro atomic force microscopy, scanning electron microscopy, and nanoindentation study

The overall consumption of acidic beverages has become more common, making the prevention and treatment of dental erosion an important consideration. The aim of this in vitro study was to evaluate the effect of various plant extracts in preventing dentin erosion. Seven experimental groups (fluoride-free water, fluoride-containing mouthwash [Colgate Plax], green tea, rosehip, clove, pomegranate, and grape seed) were formed, each consisting of 20 bovine dentin samples. The specimens were exposed daily to demineralization and remineralization cycles three times per day over 5 days through a 5-min plant extract application before each erosive episode. Surface roughness, nanohardness values, and morphological changes on dentin surfaces were examined using atomic force microscopy (AFM), nanoindentation, and scanning electron microscopy (SEM). The data were subjected to Kruskal-Wallis and Friedman tests (p < .05). There were statistically significant differences between the groups in terms of nanohardness values (p < .05), except for the pomegranate and grape seed groups. The highest nanohardness value was observed in the clove group (1.24 ± 0.34 GPa), whereas the lowest nanohardness value was noted in the grape seed group (0.20 ± 0.04 GPa). The nanohardness values of positive and negative control groups after erosion cycles were statistically higher than the initial nanohardness values (p < .05).There was no statistically significant difference between the groups in surface roughness values (p > .05). Macromolecular deposits were observed both in the SEM and AFM images of the pomegranate, Colgate, and rosehip groups. It can be concluded that the clove extract group is more successful in preventing dentin erosion than the other groups. Green tea is also effective in preventing dentin erosion, similar to clove extract. The application of plant extracts may be a new treatment strategy in preventing dentin erosion. Plant extracts may also reduce the severity of existing dentin erosion. Clove and green tea extracts may present novel natural therapy potential by inhibiting dentin erosion.

Antifungal in vitro Activity of Essential Oils against Clinical Isolates of Malassezia pachydermatis from Canine Ears: A Report from a Practice Laboratory

BACKGROUND

The yeast Malassezia pachydermatis is a commensal but also the most isolated pathogenic yeast in canine otitis externa. Essential oils (EOs) exhibit antimicrobial activity and thus could be an alternative for treatment of otitis.

OBJECTIVE

The aim of this study was to analyse the in vitro efficacy of EOs against M. pachydermatis isolates from canine ears.

MATERIALS AND METHODS

Twenty-two EOs were tested for their in vitro activity against 15 M. pachydermatis isolates by agar disc diffusion. In addition, diluted EOs were tested and volatile antifungal activity was analysed by vapour assay.

RESULTS

Most EOs showed in vitro efficacy against M. pachydermatis. A different susceptibility pattern of tested isolates was found. Overall, the most potential EO was lemon grass. Also, cinnamon leaf, clove, manuka, Indian melissa, oregano, palmarosa, and winter savory oil exhibited a strong antifungal activity. Volatile activity was proven by the inhibiting effect in vapour assay.

CONCLUSION

EOs show in vitro activity against M. pachydermatis. This study gives scientific background for the use of EOs in veterinary medicine. Diverse susceptibility patterns of different M. pachydermatis strains emphasise the helpfulness of an aromatogram as one lead for the best choice of an EO for therapy.

Use of Essential Oils by Health Care Professionals for Health Maintenance

This study explores essential oils' use by health care professionals for health maintenance. A qualitative, descriptive design was employed, and a convenience sample of 10 participants was interviewed. Four themes were identified: an essential oils' community, essential oils' use, essential oils' acceptance, and essential oils' benefits and harms.

Plants of the Genus Lavandula: From Farm to Pharmacy

The Lavandula genus, belonging to the Lamiaceae, includes 39 species, with nearly 400 registered cultivars. Lavandula are worldwide plants that occur over the Mediterranean, Europe, North Africa, southwest Asia to southeast India. Lavandula plants have been used since ancient time to flavor and preserved food, to treat diseases including wound healing, sedative, antispasmodic, microbial and viral infections. Numerous researches have described the chemical composition and the primary components of lavender oils are the monoterpenoids (linalool, linalyl acetate, 1,8-cineole, β-ocimene, terpinen-4-ol, and camphor), sesquiterpenoids (β-caryophyllene and nerolidol) and other terpenoid compounds (e.g., perillyl alcohol). The high concentrations of linalyl acetate make them attractive in perfumery, flavoring, cosmetics and soap industries. Currently, data on the antimicrobial activity of lavender plants have been scientifically confirmed. Indeed, lavender essential oils possess wide spectra of biological activities such as antispasmodic, carminative, analgesic, sedative, hypotensive, antiseptic, antimicrobial, antifungal, antidiuretic and general tonic action. In addition, clinical studies support their uses as treatment of health conditions. However, further clinical studies are necessary to define the magnitude of the efficacy, mechanisms of action, optimal doses, long-term safety, and, potential side effects of lavender plants.

Antibacterial and Antifungal Activity of Essential Oils against Pathogens Responsible for Otitis Externa in Dogs and Cats

Background: 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.

A quantitative model for dermal infection and oedema in BALB/c mice pinna

Background

Pharmaceutical industry demands innovation for developing new molecules to improve effectiveness and safety of therapeutic medicines. Preclinical assays are the first tests performed to evaluate new therapeutic molecules using animal models. Currently, there are several models for evaluation of treatments, for dermal oedema or infection. However, the most common or usual way is to induce the inflammation with chemical substances instead of infectious agents. On the other hand, this kind of models require the implementation of histological techniques and the interpretation of pathologies to verify the effectiveness of the therapy under assessment.

This work was focused on developing a quantitative model of infection and oedema in mouse pinna. The infection was achieved with a strain of Streptococcus pyogenes that was inoculated in an injury induced at the auricle of BALB/c mice, the induced oedema was recorded by measuring the ear thickness with a digital micrometer and histopathological analysis was performed to verify the damage. The presence of S. pyogenes at the infection site was determined every day by culture.

Results

Our results showed that S. pyogenes can infect the mouse pinna and that it can be recovered at least for up to 4 days from the infected site; we also found that S. pyogenes can induce a bigger oedema than the PBS-treated control for at least 7 days; our results were validated with an antibacterial and anti-inflammatory formulation made with ciprofloxacin and hydrocortisone.

Conclusions

The model we developed led us to emulate a dermal infection and allowed us to objectively evaluate the increase or decrease of the oedema by measuring the thickness of the ear pinna, and to determine the presence of the pathogen in the infection site. We consider that the model could be useful for assessment of new anti-inflammatory or antibacterial therapies for dermal infections.

Essential oils in the treatment of respiratory tract diseases highlighting their role in bacterial infections and their anti-inflammatory action: a review

The appearance of multidrug resistant bacteria and growing antibiotic resistance is leading to a continuous need for discovering new drugs and alternative treatments against infections. The investigation of the antibacterial effect of essential oils (EOs), which are commonly used nowadays in cosmetics, health care, traditional medicine and food industry, could be one of the promising solutions for this worldwide problem. EOs have a complex mode of action due to their multiple composition. Respiratory tract diseases (RTDs) associated with bacterial infection and inflammation affect a large number of people from every age group worldwide. Because of volatility, EOs can easily reach the upper and lower parts of the respiratory tract via inhalation. Moreover, due to their antimicrobial and anti-inflammatory potency, they offer an effective treatment in respiratory tract infections (RTIs). The purpose of this review is to describe the most frequently developing infections of the upper and lower respiratory tract and to show methods used for the determination of the antibacterial activity of EOs by gaseous contact. The mode of action of EOs on bacterial cells and their anti-inflammatory action are also discussed. Results coming from recently performed in vivo animal studies as well as human trials are also reported. Patents deal with the role of EOs and their volatile constituents in the treatment of RTIs are also introduced. On the whole, this review aimed at showing EOs as potential antimicrobials and as anti-inflammatory agents to alleviate symptoms and signs of RTDs including RTIs. Copyright © 2015 John Wiley & Sons, Ltd.