Allergen fragrance molecules: a potential relief for COVID-19.

BACKGROUND: The latest coronavirus SARS-CoV-2, discovered in China and rapidly spread Worldwide. COVID-19 affected millions of people and killed hundreds of thousands worldwide. There are many ongoing studies investigating drug(s) suitable for preventing and/or treating this pandemic; however, there are no specific drugs or vaccines available to treat or prevent SARS-CoV-2 as of today. METHODS: Fifty-eight fragrance materials, which are classified as allergen fragrance molecules, were selected and used in this study. Docking simulations were carried out using four functional proteins; the Covid19 Main Protase (MPro), Receptor binding domain (RBD) of spike protein, Nucleocapsid, and host Bromodomain protein (BRD2), as target macromolecules. Three different software, AutoDock, AutoDock Vina (Vina), and Molegro Virtual Docker (MVD), running a total of four different docking protocol with optimized energy functions were used. Results were compared with the five molecules reported in the literature as potential drugs against COVID-19. Virtual screening was carried out using Vina, molecules satisfying our cut-off (- 6.5 kcal/mol) binding affinity was confirmed by MVD. Selected molecules were analyzed using the flexible docking protocol of Vina and AutoDock default settings. RESULTS: Ten out of 58 allergen fragrance molecules were selected for further docking studies. MPro and BRD2 are potential targets for the tested allergen fragrance molecules, while RBD and Nucleocapsid showed weak binding energies. According to AutoDock results, three molecules, Benzyl Cinnamate, Dihydroambrettolide, and Galaxolide, had good binding affinities to BRD2. While Dihydroambrettolide and Galaxolide showed the potential to bind to MPro, Sclareol and Vertofix had the best calculated binding affinities to this target. When the flexible docking results analyzed, all the molecules tested had better calculated binding affinities as expected. Benzyl Benzoate and Benzyl Salicylate showed good binding affinities to BRD2. In the case of MPro, Sclareol had the lowest binding affinity among all the tested allergen fragrance molecules. CONCLUSION: Allergen fragrance molecules are readily available, cost-efficient, and shown to be safe for human use. Results showed that several of these molecules had comparable binding affinities as the potential drug molecules reported in the literature to target proteins. Thus, these allergen molecules at correct doses could have significant health benefits.

Potential use of polymers and their complexes as media for storage and delivery of fragrances.

The use of fragrances is often essential to create an elegant, welcoming, or exhilarating environment. Through encapsulation, the release and delivery of fragrances are customized in many consumer products. For such purposes, cost-effective techniques have been developed and employed with the use of various polymers and porous organic materials to efficiently impart fragrances to foods and various other consumer products. After entrapment or uptake/storage of fragrant molecules within a polymeric complex, the properties can be investigated by automated thermal desorption (ATD) analysis. For efficient delivery, fragrances are adsorbed (or entrapped) in some media (e.g., fabric or paper). The release of such entrapped fragrances usually is achieved by spraying. Fragrances can be also loaded in a media by purging aroma gases or by adding fragrance essence directly into a liquid medium. Porous materials, such as zeolites, have been traditionally used for air purification as well as in cosmetics and similar applications. Similarly, other polymeric porous complexes have also been used in fragrance delivery as a templating agent for aromatherapy textiles. Such polymeric materials offer an advantage in terms of development of new hybrid blends via homogenous mixing of two or more matrices. Such blends may possess different desirable physical properties as encapsulants. This review article is aimed at presenting an overview of polymers and their complexes as the main media of fragrance encapsulation. This study also discusses the expansion and future application of porous materials as host matrices for fragrances.

Qualitative and quantitative composition of essential oils: A literature-based database on contact allergens used for safety assessment.

The risks related to the use of essential oils are difficult to ascertain at present, due in part to the large number of different oils available on the market, making it difficult for the risk assessor. Essential oils may contain skin allergens in significant amounts, and could thus pose a risk to the consumer. The aim of our study was to collect as much qualitative and quantitative data as possible on allergens present in essential oils. 11 types of essential oils, with 25 respective subspecies, were taken into account based on a previous survey. Based on the literature, 517 dosages were recorded from 112 publications, providing precious information for probabilistic exposure assessment purposes. 22 substances recognized as established allergens were found in the essential oils we included. Of these, 11 are also found in cosmetics as fragrance components. These results are of major importance regarding co-exposure to fragrance allergens. Moreover, this could lead to regulatory measures for essential oils in the future, as it is the case for cosmetic products, in order to better protect consumers against skin allergy.

Usage patterns of aromatherapy among the French general population: A descriptive study focusing on dermal exposure.

Although likely benefits of aromatherapy are well documented, little is known about essential oils consumption and exposure to molecules present in the oils. The aim of our study was to determine usage patterns of 12 types of essential oils among a quite large panel, sorted per sex and quintile of age from birth to 70. A survey was conducted in September 2014 among 1507 French individuals, selected to build a representative panel of the general population. The key point of our study, apart from the fact that it has never been done among general population, was the focus on dermal exposure. Information about types of essential oils used, skin areas exposed, frequencies and quantities were collected. Our work revealed that some sub-populations could be significantly exposed to molecules of toxicological concern, especially in terms of skin sensitization. This work is the first step to assess human exposure to these molecules, and will help safety authorities and risk managers to protect the population.

Evaluation of the harmonizing effect of ylang-ylang oil on humans after inhalation.

Scientific evaluations of the effects of fragrances on humans are rather scarce. The aim of this investigation was to study the effects of ylang-ylang oil (Cananga odorata, Annonaceae) on hu-man physiological parameters and self-evaluation. Twenty-four healthy volunteers participated in the experiments. Fragrances were administered by inhalation. Physiological parameters recorded were skin temperature, pulse rate, breathing rate and blood pressure. Self-evaluation was assessed in terms of alertness, attentiveness, calmness, mood, relaxation and vigor. Additionally, fragrances were rated in terms of pleasantness, intensity and effect. The present investigation showed that ylang-ylang oil may be characterized by the concept of "harmonization" rather than relaxation/sedation. Compared to an odorless placebo, ylang-ylang oil caused significant decreases in blood pressure and pulse rate as well as significant increases of subjective attentiveness and alertness. Correlational analyses revealed that the observed effects are mainly due to a subjective odor experience.

Evaluation of the dermal subchronic toxicity of diphenyl ether in the rat.

Diphenyl ether (DPE) was investigated to determine the dermal absorption parameters and subchronic toxicity of this fragrance ingredient. For the absorption, distribution and elimination study, Sprague-Dawley rats received a dermal application of [14C]DPE under a semi-occlusive dressing for 6 h. DPE was diluted in diethyl phthalate (DEP) to administer a total application volume of 2 ml/kg and concentrations of 0.5, 5 and 50% (approximately equal to 10, 100 and 1000 mg DPE/kg body weight). Approximately 17.7% of the administered dose was eliminated in the urine, with small amounts also found in the feces (1.18-3.79%). At 72 h post-dosing, approximately 0.2% of the applied dose was retained in the body with low levels also measured in the liver, kidney and gastrointestinal tract (approximately equal to 0.04, 0.02 and 0.3%, respectively). The 13-week subchronic toxicity study was performed with groups of 12 Sprague-Dawley rats/sex/dose that received semi-occluded daily dermal applications of DPE for 6 h/day. All groups were dosed at a constant 2 ml/kg body weight volume of DPE in the DEP vehicle at concentrations to administer 0, 100, 300 or 1000 mg DPE/kg body weight/day. At the high dose level, there was a slight reduction in body weight gain in males (13%), increase in albumin (5-6%) and phosphate (10-15%) levels in both sexes, a reduction of cholesterol in females (14%), an increase in kidney (17%) and brain (8%) weights in males, and an increase in liver weight (18-19%) in both sexes. No histopathological lesions were seen in any organ examined. At 300 mg/kg body weight/day, the only notable findings were an increase in liver weight (10%) in both sexes and a slight increase in albumin (5%) in females. In addition, skin irritation reactions at the site of application were observed in all DPE dose groups. The systemic no-observed-effect level (NOEL) in this study is 100 mg/kg body weight/day. Owing to mitigating factors, the systemic findings were judged to lack biological significance and the no-observed-adverse-effect level (NOAEL) was determined to be 1000 mg/kg body weight/day.

Fungistatic activity of some perfumes against otomycotic pathogens.

The sporostatic effect of five otomycotic pathogens, i.e. Aspergillus niger, A. flavus, Absidia corymbifera, Penicillium nigricans and Candida albicans to nine different perfumes was determined on the basis of their spore germination. These organisms were isolated from patients suffering from fungal infection of the external auditory canal. Volatile vapours emanating from musk, phulwari, jasmine, nagchampa and bela caused approximately 100% inhibition in spore germination of all the test fungi. Volatiles emanating from chandan, khas and hina showed no inhibition for the test pathogens, displaying their resistant character to these perfumes.