An outbreak of allergic contact dermatitis caused by citral in beauticians working in a health spa

Influence of vegetation on the composition of essential oil from (Melissa officinalis L.)

Lemon balm (Melissa officinalis L.) is a perennial plant of the family Lamiaceae, which is used in folk medicine and the food industry, as well as being processed to obtain essential oil. The aim of the special work is to monitor the influence of vegetation on the composition of the essential oil. The chemical composition of essential oils, obtained by steam distillation from lemon balm cultivated in North-eastern Bulgaria, has been determined. The plants were harvested in two periods of vegetation - the first at the end of June and second - at the end of August 2020. The main components in the oil from the first cut are geranial (26.41%), neral (19.55%), (E)-β-caryophyllene (17.46%), germacrene D (7.86%) and β-citronellal (3.24%). In the oil from the second cut, the main components are geranial (37.26%), neral (28.46%), (E)-β- caryophyllene (6.65%), geraniol (4.72%), and β-citronellal (3.04%). The oil from the second harvest has a high content of the main components of geranial, neral and geraniol and a lower content of (E)-β- caryophyllene and germacrene D. Variations in the amounts are also present in other compounds.

Application of direct peptide reactivity assay for assessing the skin sensitization potential of essential oils

Plant-derived products are frequently found as ingredients in cosmetics. However, the current data show non-neglectable skin sensitizing potential of these preparations suggesting an urgent need for data regarding their health safety profile. The aim of this study was to assess the skin sensitization potential of commercial essential oils by selected Lamiaceae species (Lavandula angustifolia, Melissa officinalis, Mentha longifolia, Thymus vulgaris, Salvia officinalis, and Rosmarinus officinalis) using a chemistry-based Direct Peptide Reactivity Assay (DPRA) in order to predict their potential allergic properties. In the DPRA assay, nucleophile-containing synthetic peptides (cysteine peptide and lysine peptide) were incubated with the test substance for 24 h. Depletion of the peptide in the reaction mixture was measured by high-pressure liquid chromatography (HPLC) using UV detection and the average peptide depletion data for cysteine and lysine was then calculated. Menthae longifoliae aetheroleum showed no or minimal reactivity with 4.48% cysteine depletion, Rosmarini aetheroleum and Salviae aetheroleum showed low reactivity with the 12.79% and 15.34% of cysteine depletion, respectively, while the other analyzed essential oils showed moderate reactivity with the cysteine depletion between 23.21 and 48.43%. According to DPRA predictive analysis, only Menthae longifoliae aetheroleum can be classified as negative, while all other essential oils may be classified as positive, thus having the potential to cause skin sensitization.

Chemical Composition of Essential Oils of Aromatic and Medicinal Herbs Cultivated in Greece-Benefits and Drawbacks

The current study investigated and determined the major compounds of six essential oils derived from different plant species cultivated in Greece (Lavandula angustifolia, Origanum vulgare, Pistacia lentiscus var. chia, Citrus reticulata, Citrus limon and Crithmum maritimum). The results proved that all these essential oils have a high potential for use as food preservatives, since among the compounds determined were sabinene, b-myrcene, a-pinene, carvacrol and limonene, all of which were responsible for the strong antimicrobial activity against Staphylococcus aureus. However, the amounts of some compounds, such as linalool and citral, were at high levels, and this can be a danger for some sensitive population groups due to allergic reactions. The essential oil compounds which were identified using GC-MS and quantified through GC-FID represented more than 95% of the total essential oils of the investigated plant species. Finally, all essential oils provided high phenolic content.

Danger-Associated Molecular Patterns (DAMPs): the Derivatives and Triggers of Inflammation

PURPOSE OF REVIEW

Allergen is an umbrella term for irritants of diverse origin. Along with other offenders such as pathogens, mutagens, xenobiotics, and pollutants, allergens can be grouped as inflammatory agents. Danger-associated molecular patterns (DAMPs) are altered metabolism products of necrotic or stressed cells, which are deemed as alarm signals by the innate immune system. Like inflammation, DAMPs play a role in correcting the altered physiological state, but in excess, they can be lethal due to their signal transduction roles. In a vicious loop, inflammatory agents are DAMP generators and DAMPs create a pro-inflammatory state. Only a handful of DAMPs such as uric acid, mtDNA, extracellular ATP, HSPs, amyloid β, S100, HMGB1, and ECM proteins have been studied till now. A large number of DAMPs are still obscure, in need to be unveiled. The identification and functional characterization of those DAMPs in inflammation pathways can be insightful.

RECENT FINDINGS

As inflammation and immune activation have been implicated in almost all pathologies, studies on them have been intensified in recent times. Consequently, the pathologic mechanisms of various DAMPs have emerged. Following PRR ligation, the activation of inflammasome, MAPK, and NF-kB is some of the common pathways. The limited number of recognized DAMPs are only a fraction of the vast array of other DAMPs. In fact, any misplaced or abnormal level of metabolite can be a DAMP. Sophisticated analysis studies can reveal the full profile of the DAMPs. Lowering the level of DAMPs is useful therapeutic intervention but certainly not as effective as avoiding the DAMP generators, i.e., the inflammatory agents. So, rather than mitigating DAMPs, efforts should be focused on the elimination of inflammatory agents.

Recent Trends in Occupational Contact Dermatitis

Occupational contact dermatitis (OCD) remains prevalent among workers and impacts quality of life and workability. The purpose of this review is to summarize the recent advances in occupational contact dermatitis as well as potential hazardous agents in the workplaces causing OCD. The review covers new developments in the epidemiology, etiology, diagnosis, and management of occupational contact dermatitis. This article also provides updated information on the prevalence of work-related skin symptoms and on new contact allergens among working population. It is emphasized that in the context of prevention of OCD, special attention should be focused on the identified high-risk occupational groups, especially healthcare workers and hairdressers starting with the apprentices. Current approaches include working out the standards and guidelines to improve the education, knowledge, diagnosis, and management of OCD based on a multidisciplinary team of medical specialists and an employer.