We aimed to incorporate Thymbra capitata essential oil (TCEO), a potent antimicrobial natural product against bacterial vaginosis (BV)-related bacteria, in a suitable drug delivery system. We used vaginal sheets as dosage form to promote immediate relief of the typical abundant vaginal discharge with unpleasant odour. Excipients were selected to promote the healthy vaginal environment reestablishment and bioadhesion of formulations, while the TCEO acts directly on BV pathogens. We characterized vaginal sheets with TCEO in regard to technological characterization, predictable in vivo performance, in vitro efficacy and safety. Vaginal sheet D.O (acid lactic buffer, gelatine, glycerine, chitosan coated with TCEO 1% w/w) presented a higher buffer capacity and ability to absorb vaginal fluid simulant (VFS) among all vaginal sheets with EO, showing one of the most promising bioadhesive profiles, an excellent flexibility and structure that allow it to be easily rolled for application. Vaginal sheet D.O with 0.32 µL/mL TCEO was able to significantly reduce the bacterial load of all in vitro tested Gardnerella species. Although vaginal sheet D.O presented toxicity at some concentrations, this product was developed for a short time period of treatment, so this toxicity can probably be limited or even reversed when the treatment ends.

Natural mineral waters (NMWs) and plant extracts have long been valued for their therapeutic properties and skin benefits. This study investigated, in vitro, the role of five Portuguese NMWs (A-E), combined with plant extracts from five species (Ficus carica L., Rubus idaeus L., Vaccinium myrtillus, Cistus ladanifer and Thymus x citriodorus) as bioactive ingredients. Antioxidant capacity was assessed using the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method. Cellular biocompatibility was evaluated in fibroblasts (L929) and macrophages (RAW 264.7). Skin-repairing and anti-senescence properties were evaluated in L929 cells through the scratch-wound method and β-galactosidase assay. Superoxide dismutase (SOD) was quantified using a commercial kit, and lipopolysaccharide-induced reactive oxygen species (ROS) were quantified using a fluorescent probe (H₂DCFDA) in RAW 264.7. The results highlighted the beneficial impact of extracts combined with NMWs. An increase in antioxidant capacity of up to 90% was observed in mixtures comprising Ficus carica L., compared with NMWs alone. In contrast, mixtures with Cistus ladanifer showed promising anti-aging potential, with a 40% decrease in senescent cells and a 33% ROS reduction. Rubus idaeus L. extract produced an increase in cell migration capacity (up to 50%), depending on the NMW. This study highlights the potential synergism of natural ingredients with plant extracts for anti-aging.

The numerous health benefits associated with the use of plants in traditional medicine can be linked to secondary metabolites in the products obtained through the hydrodistillation process, such as hydrolates and essential oils (EOs). This study aimed to assess the chemical profile and the antioxidant, antimicrobial, cytotoxic, and anti-inflammatory activities of two hydrodistillation products obtained from four plants belonging to two distinct families: chamomile (Matricaria chamomilla), purple coneflower (Echinacea purpurea), conehead thyme (Thymbra capitata), and basil (Ocimum basilicum). The EOs were found to be more effective than hydrolates in inhibiting microorganisms’ growth, registering MIC values equal to or higher than 50% (v/v), except for T. capitata. Only T. capitata demonstrated the ability to reduce NO levels with both hydrolate and EO. Moreover, it inhibited the cell growth of RAW 264.7, 3T3, and HaCaT lines at the tested concentrations. In contrast, O. basilicum EO did not affect the cell proliferation of the tested cell lines in concentrations below 0.063% (v/v) and showed a significant reduction in the macrophage NO production at all concentrations. Thus, EOs showed a superior biological activity than hydrolates. In particular, O. basilicum EO was found to be a promising candidate for therapeutic applications on the skin.

Skin aging is influenced by intrinsic and extrinsic factors, leading to structural changes in the skin. Current anti-aging cosmetic trends emphasize innovative natural ingredients, including plant extracts, thermal waters, and botanical hydrolats. This work aims to develop six natural anti-aging cosmetics (two serums, two day creams, and two night creams) with innovative and non-irritating profiles. The rational design was guided by market analysis and ingredient properties. Prototype formulations were created with two core mixtures: (1) natural mineral water from Termas de Unhais da Serra and Thymus × citriodorus hydrolat and (2) natural mineral water from Termas de Chaves and aqueous Vaccinium myrtillus (blueberry) extract. The products were evaluated for stability (4 °C and 40 °C, 4 weeks), safety (according to EC Regulation No. 1223/2009), including in vitro testing for skin irritation potential (epiderm model; OECD TG 439). The market study highlighted a gap in anti-aging products combining natural extracts and thermal waters. All prototypes showed desirable textures and remained stable under test conditions. No irritating effects were observed. The results support the development of effective anti-aging cosmetics rooted in natural resources. These innovative products can meet the market demand for natural and sustainable skincare solutions.

Pityriasis versicolor (PV) is a condition of the skin caused by the yeast Malassezia that manifests itself through scaly, well-demarcated patches with a dark, depigmented or erythematous coloration. Recurrence is common, and few treatment alternatives are available in the market. In this study, we aim to develop a body lotion for the improvement of PV skin with natural ingredients, such as essential oils and natural mineral waters. The antimicrobial activity of the selected ingredients was evaluated by the broth microdilution test, the volatile assay and the checkerboard assay. In addition, the cytotoxicity to HaCaT was assessed by the MTT assay. Finally, the most promising ingredients were combined in a formulation for topical application, and its efficacy and safety profile was assessed in vitro. Origanum vulgare essential oil was found to be the most active against M. furfur (MIC 0.625% v/v) and synergic with São Pedro do Sul natural mineral water (SPS NMW), while also being biocompatible with keratinocytes (EC50 < 0.06% v/v). The body lotion that was formulated with the most natural ingredients possible (>95%) and showed great activity against M. furfur, being able to reduce its growth by 100%; in addition, it was found to be a non-irritant in 3D reconstructed skin models.