Linoleic acid salt with ultrapure soft water as an antibacterial combination against dermato-pathogenic Staphylococcus spp

Evaluation of phytochemical composition, toxicity in Drosophila melanogaster and effects on antibiotics modulation of Plathymenia reticulata Benth extract

Bacterial resistance is interfering with the action of antibiotics for clinical use in treating pathologies. The search for new substances capable of combating this resistance is necessary. An alternative to the search for these substances is in the extract of medicinal plants. Plathymenia reticulata, plant of the Fabaceae family, is a common tree species from the Brazilian cerrado, and is commonly used in areas of environmental degradation. This species is rich in phenolic compounds, such as flavonoids and tannins, compounds that are associated with various biological effects. A hydroethanolic extract from the bark of Plathymenia reticulata (HEPrB) was produced and then tests were carried out to verify the direct antibacterial activity, the modulatory effect of antibiotics for clinical use and their toxicity in Drosophila melanogaster flies. Through the analysis with UPLC, a wide variety of flavonoids contained in the HEPrB was observed. Direct antibacterial activity was observed for the standard strain of Staphylococcus aureus, however, the extract showed antagonistic activity or no significance in relation to the antibiotics tested in this study. As for toxicity, the HEPrB did not show significant damage in the proposed model. The results emphasize care when associating the consumption of teas with treatments with antibiotics for clinical use.

Reused Plant Fried Oil: A Case Study with Home-Made Soaps

The study aimed to analyze the possibility of waste frying oil utilization in home-made soap production. Soaps were made from unheated and fried rapeseed, sunflower and palm oils that had total polar material (TPM) values up to 24%. Physicochemical and microbial analyses were performed on produced samples to check their quality. The hardness increased with the degradation level of rapeseed and palm oils, and opposite findings were obtained for sunflower-made soaps. The highest malondialdehyde (MDA) contents were recorded for sunflower oil-made samples, with the maximum of 6.61 µg/g, and the lowest for the palm oil-made samples, with the maximum of 0.94 µg/g. The antimicrobial assessment showed no significant (p > 0.05) differences between control soap samples and soaps made of oils with the highest TPM value. Gram-positive bacteria (methicillin-resistant Staphylococcus aureus: MRSA) were the most sensitive chosen microorganisms, compared to Gram-negative bacteria and yeasts. The obtained results did not show exact differences between experimentally produced soap samples from fried or not fried oils; these findings highlight the potential of home-made soap production from this byproduct.

Epithelial barrier repair and prevention of allergy

Allergic diseases have in common a dysfunctional epithelial barrier, which allows the penetration of allergens and microbes, leading to the release of type 2 cytokines that drive allergic inflammation. The accessibility of skin, compared with lung or gastrointestinal tissue, has facilitated detailed investigations into mechanisms underlying epithelial barrier dysfunction in atopic dermatitis (AD). This Review describes the formation of the skin barrier and analyzes the link between altered skin barrier formation and the pathogenesis of AD. The keratinocyte differentiation process is under tight regulation. During epidermal differentiation, keratinocytes sequentially switch gene expression programs, resulting in terminal differentiation and the formation of a mature stratum corneum, which is essential for the skin to prevent allergen or microbial invasion. Abnormalities in keratinocyte differentiation in AD skin result in hyperproliferation of the basal layer of epidermis, inhibition of markers of terminal differentiation, and barrier lipid abnormalities, compromising skin barrier and antimicrobial function. There is also compelling evidence for epithelial dysregulation in asthma, food allergy, eosinophilic esophagitis, and allergic rhinosinusitis. This Review examines current epithelial barrier repair strategies as an approach for allergy prevention or intervention.

Reduction in the colonization of Staphylococcus aureus on the skin surface under calcium-/magnesium-depleted conditions

Excessive expansion of Staphylococcus aureus is associated with several skin diseases, including atopic dermatitis (AD). Recently, we have demonstrated that washing skins with ultra-pure soft water containing little bivalent metal ions improved skin conditions of atopic subjects. In this study, we investigated the roles of calcium or magnesium on the proliferation of S. aureus both in vitro and in vivo. Depletion of calcium and magnesium in the culture medium significantly suppressed the expansion of S. aureus growth. When S. aureus, diluted with water containing calcium/magnesium at the concentration of medium-hard water (83·0 mg l^-1 as CaCO₃ ) or the one that contains little calcium/magnesium, was applied onto the tape-stripped skin of Hos:HR-1 mice, growth of S. aureus in water without those minerals on the skin was suppressed. These results suggest that depletion of both calcium and magnesium abrogate the proliferation of S. aureus not only in the culture system but also on the skin surface of mice. Since colonization of S. aureus on the skin is well-known to exacerbate AD symptoms, usage of ultra-pure soft water containing less calcium and magnesium may improve the skin condition through the suppression of S. aureus growth on the skin of patients with skin problems.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates the importance of calcium and magnesium for the colonization and growth of Staphylococcus aureus by using both in vitro culture systems and in vivo experiments on the murine skin. Our results indicate that the removal of these metal ions is probably beneficial for protecting the skin from S. aureus. Thus, using ultra-pure soft water without metal ions may improve the skin condition of patients with skin problems through the protection from S. aureus colonization.