In Vitro Human Skin Penetration, Antioxidant and Antimicrobial Activity of Ethanol-Water Extract of Fireweed (Epilobium angustifolium L.)

Antibacterial, Antibiofilm, and Antioxidant Activities of Aqueous Crude Gymnema inodorum Leaf Extract against Vancomycin-Resistant Enterococcus faecium

Vancomycin-resistant Enterococcus faecium (VREF) causes nosocomial infections with high mortality and morbidity rates. This study aimed to evaluate the antibacterial and antibiofilm activities of aqueous crude Gymnema inodorum leaf extract (GIE) against the VREF ATCC 700221 strain. The antimicrobial activity of GIE against VREF was performed using disk diffusion and broth microdilution. The antibiofilm activities were evaluated using the crystal violet staining assay. The antioxidant potential was evaluated. Preliminary screening of the antimicrobial activity of 50 and 100 µg/disk of GIE against VREF revealed inhibition zones of 8.33 ± 0.58 mm and 8.67 ± 0.29 mm, respectively. Additionally, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against VREF were 125 and ≥ 250 mg/mL, respectively. SEM analysis showed that treatment with GIE caused morphological changes, including incomplete cell division, damaged cell walls, and cell content leakage, suggesting a disruption of bacterial cells. GIE also inhibited and eradicated biofilms formed by VREF. The extract exhibited antioxidant activities in the DPPH and ABTS assays. While GIE shows potential as an antibacterial and antibiofilm agent, further studies are necessary to fully understand the underlying mechanisms and optimize its use for therapeutic applications.

Laurocapram, a transdermal enhancer, boosts cephalosporin's antibacterial activity against Methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA), a notorious bacterium with high drug resistance and easy recurrence after surgery, has posed significant clinical treatment challenges. In the current scarcity of new antibiotics, the identification of adjuvants to existing antibiotics is a promising approach to combat infections caused by multidrug-resistant Gram-positive bacteria. The in vitro synergy test, which included a MIC assay, time-kill curve, antimicrobial susceptibility testing, and live/dead bacteria staining assay, revealed that laurocapram, a widely used chemical transdermal enhancer, could potentiate the antibacterial activity of cephalosporins against MRSA. In vitro, laurocapram combined with cefixime showed an excellent synergistic activity against MRSA (FICI = 0.28 ± 0.00). In addition, the combination of laurocapram and cefixime may inhibited the formation of MRSA biofilm and caused cell membrane damage. Following that, we discovered that combining laurocapram with cefixime could alleviate the symptoms of mice in the MRSA skin infection model and the MRSA pneumonia model. In conclusion, laurocapram is a promising and low-cost antibacterial adjuvant, providing a new strategy for further exploring the use of lower doses of cephalosporins to combat MRSA infection.

Inclusion complexes of β-cyclodextrin with isomeric ester aroma compounds: Preparation, characterization, mechanism study, and controlled release

Cyclodextrins (CDs) have been discovered to provide an efficient solution to the limited application of ester aroma molecules used in food, tobacco, and medication due to their strong smell and unstable storage. This work combined molecular modeling and experimental to analyze the conformation and controlled release of isomeric ester aroma compounds/β-CD inclusion complexes (ICs). The investigation revealed that ester aroma compounds could be effectively encapsulated within the β-CD cavity, forming ICs with low binding affinity. Furthermore, the key driving forces in ICs were identified as hydrogen bonds and van der Waals interactions through theoretical simulation. Results from the Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR) and Isothermal titration calorimetry (ITC) experiments confirmed the intermolecular interaction predicted by the molecular model. Notably, the release rate of aroma compounds from L-menthyl acetate/β-CD (LMA/β-CD) IC exceeded that of terpinyl acetate/β-CD (TA/β-CD) IC. This difference is attributed to the length of the chain of aroma molecules and the variation in the position of functional groups, influencing the stable formation of ICs with β-CD. These findings hold potential implications for refining the application of ICs across diverse industries.

Investigating the Anti-Inflammatory Properties and Skin Penetration Ability of Cornelian Cherry (Cornus mas L.) Extracts

Plant extracts can be a valuable source of biologically active compounds in many cosmetic preparations. Their effect depends on the phytochemicals they contain and their ability to penetrate the skin. Therefore, in this study, the possibility of skin penetration by phenolic acids contained in dogwood extracts of different fruit colors (yellow, red, and dark ruby red) prepared using different extractants was investigated. These analyses were performed using a Franz chamber and HPLC-UV chromatography. Moreover, the antioxidant properties of the tested extracts were compared and their impact on the intracellular level of free radicals in skin cells was assessed. The cytotoxicity of these extracts towards keratinocytes and fibroblasts was also analyzed and their anti-inflammatory properties were assessed using the enzyme-linked immunosorbent assay (ELISA). The analyses showed differences in the penetration of individual phenolic acids into the skin and different biological activities of the tested extracts. None of the extracts had cytotoxic effects on skin cells in vitro, and the strongest antioxidant and anti-inflammatory properties were found in dogwood extracts with dark ruby red fruits.

Kombucha as a Potential Active Ingredient in Cosmetics-An Ex Vivo Skin Permeation Study

Kombucha is a non-alcoholic beverage, that is increasingly used in the cosmetic industry. The available literature reports the positive effects of kombucha on the skin, in particular its antioxidant action. However, there is a lack of information on skin permeation and the accumulation of active ingredients showing such effects. Skin aging is largely dependent on oxidative stress, therefore in our study we assessed the ex vivo permeation of two types of kombucha (green and black tea) through porcine skin. The antioxidant activity (DPPH, ABTS, FRAP methods) and total polyphenol content of these extracts were determined before and after permeation testing. Moreover, the content of selected phenolic acids as well as caffeine was assessed. Skin permeation was determined using a Franz diffusion cell. The antioxidant activity of both Kombuchas was found to be high. In addition, gallic acid, chlorogenic acid, protocatechuic acid, coumaric acid, m-hydroxybenzoic acid, and caffeine were identified. A 24-h ex vivo study showed the permeation of some phenolic acids and caffeine and their accumulation in the skin. Our results confirm the importance of studying the skin permeation of what are still little known ingredients in cosmetic preparations. Evaluation of the accumulation of these ingredients can guarantee the efficacy of such preparations.

Recreating Human Skin In Vitro: Should the Microbiota Be Taken into Account?

Skin plays crucial roles in the human body: besides protecting the organism from external threats, it acts as a thermal regulator, is responsible for the sense of touch, hosts microbial communities (the skin microbiota) involved in preventing the invasion of foreign pathogens, contains immunocompetent cells that maintain a healthy immunogenic/tolerogenic balance, and is a suitable route for drug administration. In the skin, four defense levels can be identified: besides the physical, chemical, and immune barriers that are inherent to the tissue, the skin microbiota (i.e., the numerous microorganisms living on the skin surface) provides an additional barrier. Studying the skin barrier function or the effects of drugs or cosmetic agents on human skin is a difficult task since snapshot evidence can only be obtained using bioptic samples where dynamic processes cannot properly be followed. To overcome these limitations, many different in vitro models of human skin have been developed that are characterized by diverse levels of complexity in terms of chemical, structural, and cellular composition. The aim of this review is to summarize and discuss the advantages and disadvantages of the different human skin models so far available and to underline how the insertion of a proper microbiota would positively impact an in vitro human skin model in an attempt to better mimic conditions in vivo.

Investigation of Epilobium hirsutum L. Optimized Extract's Anti-Inflammatory and Antitumor Potential

Epilobium hirsutum L., commonly known as hairy willowherb, is a perennial herbaceous plant native to Europe and Asia. In Romania, the Epilobium genus includes 17 species that are used in folk medicine for various purposes. This study aimed to investigate the anti-inflammatory and antitumor potential of the optimized extract of Epilobium hirsutum (EH) in animal models. The first study investigated the anti-inflammatory properties of EH optimized extract and the model used was carrageenan-induced paw inflammation. Wistar rats were divided into three groups: negative control, positive control treated with indomethacin, and a group treated with the extract. Oxidative stress markers, cytokine levels, and protein expressions were assessed. The extract demonstrated anti-inflammatory properties comparable to those of the control group. In the second study, the antitumor effects of the extract were assessed using the tumor model of Ehrlich ascites carcinoma. Swiss albino mice with Ehrlich ascites were divided into four groups: negative, positive treated with cyclophosphamide (Cph), Group 3 treated with Cph and EH optimized extract, and Group 4 treated with extract alone. Samples from the ascites fluid, liver, and heart were analyzed to evaluate oxidative stress, inflammation, and cancer markers. The extract showed a reduction in tumor-associated inflammation and oxidative stress. Overall, the EH optimized extract exhibited promising anti-inflammatory and antitumor effects in the animal models studied. These findings suggest its potential as a natural adjuvant therapeutic agent for addressing inflammation and oxidative stress induced by different pathologies.

Antibacterial and Antimycotic Activity of Epilobium angustifolium L. Extracts: A Review

The aim of this work was to provide an overview of available information on the antibacterial and antifungal properties of Epilobium angustifolium extracts. A literature search of Scopus, PubMed/Medline, and Google Scholar for peer-reviewed articles published between January 2000 and June 2023 was undertaken. A total of 23 studies were eligible for inclusion in this review. Significant variation of antimicrobial activity depending on the tested species and strains, type of extract solvent, or plant organs utilized for the extract preparation was found. E. angustifolium extracts were active against both Gram-positive and Gram-negative bacteria and showed antimycotic effects against the fungi of Microsporum canis and Trichophyton tonsurans and the dermatophytes Arthroderma spp. Greater susceptibility of Gram-positive than Gram-negative bacteria to fireweed extracts was found. A strong antibacterial effect was recorded for Staphylococcus aureus, Bacillus cereus, Micrococcus luteus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii including multi-drug resistant strains. E. angustifolium extract might find practical application as an antimicrobial in wound healing, components of cosmetic products for human and animals, or as food preservatives.

Anticancer properties of bacterial cellulose membrane containing ethanolic extract of Epilobium angustifolium L

Epilobium angustifolium L. is a medicinal plant well known for its anti-inflammatory, antibacterial, antioxidant, and anticancer properties related to its high polyphenols content. In the present study, we evaluated the antiproliferative properties of ethanolic extract of E. angustifolium (EAE) against normal human fibroblasts (HDF) and selected cancer cell lines, including melanoma (A375), breast (MCF7), colon (HT-29), lung (A549) and liver (HepG2). Next, bacterial cellulose (BC) membranes were applied as a matrix for the controlled delivery of the plant extract (BC-EAE) and characterized by thermogravimetry (TG), infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) images. In addition, EAE loading and kinetic release were defined. Finally, the anticancer activity of BC-EAE was evaluated against the HT-29 cell line, which presented the highest sensitivity to the tested plant extract (IC₅₀ = 61.73 ± 6.42 µM). Our study confirmed the biocompatibility of empty BC and the dose and time-dependent cytotoxicity of the released EAE. The plant extract released from BC-2.5%EAE significantly reduced cell viability to 18.16% and 6.15% of the control values and increased number apoptotic/dead cells up to 37.53% and 66.90% after 48 and 72 h of treatment, respectively. In conclusion, our study has shown that BC membranes could be used as a carrier for the delivery of higher doses of anticancer compounds released in a sustained manner in the target tissue.

Epilobium Species: From Optimization of the Extraction Process to Evaluation of Biological Properties

Epilobium species are used in Romanian folk medicine as tinctures, tea, or tablets for ameliorating the symptoms of benign prostate hyperplasia (BPH), but scientific-based evidence is scarce for this species or other endemic plants of the same genus. Therefore, the aims of this research were to evaluate the phytochemical profile of five endemic Epilobium species (E. hirsutum L., E. parviflorum Schreb., E. palustre L. E. dodonaei Vill., and E. angustifolium L.) and to assess their in vitro biological activity. For enhanced recovery of polyphenols, a D-optimal experimental plan was developed using Modde software and the optimal working conditions were ultra-turrax-assisted extraction, for 8 min, with 30% ethanol in water. The optimized extracts were obtained from various plant parts and were further characterized by LC-MS analysis, with the major compound being oenothein B. All extracts demonstrated good antioxidant activity, evaluated by DPPH and TEAC assays. The most prominent antimicrobial potency of optimized extracts was displayed against Bacillus cereus, while against Gram-(+) bacteria, a moderate efficacy was observed. Furthermore, anti-cancer, anti-inflammatory, and antioxidant potential were assessed on normal fibroblasts and prostate carcinoma cell lines. From the evaluated optimized extracts, E. angustifolium aerial parts had the highest selectivity toward killing cancerous cells, followed by E. hirsutum aerial parts extract. For the antioxidant effect, E. hirsutum leaves and E. hirstum aerial parts extracts displayed the highest potency, decreasing ROS at the level observed for the positive control. The highest anti-inflammatory potential, based on the IL-6 and IL-8 levels, was displayed by E. dodonaei aerial parts and E. angustifolium leaves extracts. In conclusion, all five endemic species of Epilobium harvested from Romanian flora possess a diverse phytochemical composition, which supports complex biological activities.

New Ferulic Acid and Amino Acid Derivatives with Increased Cosmeceutical and Pharmaceutical Potential

Ferulic acid (FA) has been widely used in the pharmaceutical and cosmetics industry due to its, inter alia, antioxidant, antiaging and anti-inflammatory effects This compound added to cosmetic preparations can protect skin because of its photoprotective activity. However, the usefulness of FA as a therapeutic agent is limited due to its low solubility and bioavailability. The paper presents the synthesis, identification, and physicochemical properties of new FA derivatives with propyl esters of three amino acids, glycine (GPr[FA]), L-leucine (LPr[FA]), and L-proline (PPr[FA]). The NMR and FTIR spectroscopy, DSC, and TG analysis were used as analytical methods. Moreover, water solubility of the new conjugates was compared with the parent acid. Both ferulic acid and its conjugates were introduced into hydrogel and emulsion, and the resulting formulations were evaluated for stability. Additionally, in vitro penetration of all studied compounds from both formulations and for comparative purposes using Franz diffusion cells was evaluated from the solution in 70% (v/v) ethanol. Finally, cytotoxicity against murine fibroblasts L929 was tested. All of the analyzed compounds permeated pig skin and accumulated in it. LPr[FA] and PPr[FA] were characterized by much better permeability compared to the parent ferulic acid. Additionally, it was shown that all the analyzed derivatives are characterized by high antioxidant activity and lack of cytotoxicity. Therefore, they can be considered as an interesting alternative to be applied in dermatologic and cosmetic preparations.

Marine Algae Extract (Grateloupia Sparsa) for the Green Synthesis of Co3O4NPs: Antioxidant, Antibacterial, Anticancer, and Hemolytic Activities

The aqueous extract of red algae was used for bio-inspired manufacturing of cobalt oxide nanoparticles (Co3O4NPs) and for antioxidant, antibacterial, hemolytic potency, and anticancer activity. Typical, characterization techniques include UV-Vis, SEM, EDAX, TEM, FTIR, XRD, and TGA. Using an X-ray diffraction assay, the size of the Co3O4NPs crystal was determined to range from 23.2 to 11.8 nm. Based on TEM and SEM pictures, biosynthesized Co3O4NPs' had a homogeneous spherical morphology with a 28.8 to 7.6 nm average diameter. Furthermore, Co3O4NPs biological properties were investigated, including determining the antibacterial potency using the zone of inhibition (ZOI) method and determining the minimal inhibitory concentration (MIC). The antibacterial activity of Co3O4NPs was higher than that of the ciprofloxacin standard. Alternatively, scavenging of DPPH free radical investigation was carried out to test the antioxidant capacitance of Co3O4NPs, revealing significant antioxidant ability. The biosynthesized Co3O4NPs have a dose-dependent effect on erythrocyte viability, indicating that this technique is harmless. Furthermore, bioinspired Co3O4NPs effectively against HepG2 cancer cells (IC50: 201.3 μg/ml). Co3O4NPs would be a therapeutic aid due to their antioxidant, antibacterial, and anticancer properties.

Biologically Active Preparations from the Leaves of Wild Plant Species of the Genus Rubus

The plants of the genus Rubus (R.) are applied as antiseptic agents in the treatment of skin diseases. Despite the great interest in plants of this genus, there are few reports on the antioxidant and biological activities of preparations obtained from the leaves of these plants. Therefore, we decided to evaluate the antioxidant activity of preparations from leaves of wild plant species of the genus Rubus using the frequently applied DPPH, ABTS, and FRAP methods, as well as to determine the total polyphenol content using the Folin−Ciocalteau method and perform qualitative evaluation by gas chromatography−mass spectrometry (GC-MS). The bactericidal and fungicidal activities of the obtained preparations were evaluated by applying laboratory tests: using the disc and the well methods based on the standards EN 13697:2019, EN 13697:2015, and EN 1500:2013. Microbiological tests of the plant preparations against bacteria, fungi, and yeasts isolated from the environment and against reference strains were performed. Moreover, antimicrobial testing of antibiotics against the tested strains was performed for comparison. The n-octanol/water partition coefficient of the obtained preparations was determined by the shake-flask method to determine their lipophilicity. According to the results, a high content of polyphenols and other antioxidant and biologically active compounds can be thought of as the parameter responsible for the effective activity of plant preparations obtained from wild plant species of the genus Rubus. The methods for determining bactericidal and fungicidal activity clearly demonstrates that preparations with reduced ethanol content exhibit bactericidal and fungicidal activity on surfaces. Testing of hand disinfection by means of rubbing with the preparations confirmed their antimicrobial activity against Escherichia coli K12 NCTC 10538. The obtained results show that the tested preparations exhibit on average two times lower activity against the reference bacterial strains than comparable antibiotics. The preparations obtained from the leaves of R. idaeus L. and R. fruticosus L. could complement classical antibiotics. While environmental bacteria showed a similar response to the preparations and antibiotics, their sensitivity was about one-third less than that of the reference strains. Our studies have shown that the obtained preparations are highly hydrophilic (logP < 0). Thus, these preparations can only be used in lipid bilayers in the aqueous core of liposomes, not in the lipid envelope.

Possibilities of Using Medicinal Plant Extracts and Salt-Containing Raw Materials from the Aral Region for Cosmetic Purposes

The aim of this work was to study the possibility of using medicinal plants in combination with salt-containing raw materials from the Aral Sea region for cosmetic purposes. The chemical and mineralogical compositions of salts occurring in this region were studied for pharmacological and cosmetic purposes. The salt-containing raw materials were studied by X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The microflora of saline-containing raw materials and flora of the Zhaksy-Klych lake were studied. Fifty-six plant species were identified, of which 25% belong to the Asteraceae family, 32% were Poaceae, 22% were Amaranthaceae, and 21% were Tamaricaceae. Using the solid-phase microextraction (SPME) method and comprehensive two-dimensional gas chromatography−mass spectrometry, the composition of volatile compounds in such plant species as Artemisia alba L., Achilleamillifolium L., Eleagus commutate Bernh. Ex Rydb., Psoraleadrupacea Bunge, Artemisia cipa O. Vegd., Thymus vulgaris L., Morus alba L., Salvia pratensis L., Glycyrhizaglabra L., Tanacetum vulgare L., Polygonumaviculare L., Alhagipseudoalhagi Gagnebin and Peganumharmala L., chosen on the basis of their herbal components for future cosmetic products, was determined. In total, 187 different volatile compounds were found in the endemic plant species Glycyrrhizaglabra L., of which the following were dominant: 1,7-octadiene-3-, 2,6-dimethyl- with a peak area of 4.71%; caryophyllenes; bicyclo[7.2.0]4,11,11-trimethyl-8-methylene-, [1R-(1R*,4E,9S*)]—3.70%; bicyclo[2.2.1] heptane-2-1,7,7-trimethyl-,(1S)—3.46%; cyclohexanone, 5-methyl-2-(1-methylethyledene)-; 2-isopropyledene-5—2.97%; menthol; cyclohexanol, 5-methyl-2-(1-methylethyl)-; p-menthane-3-ol; menthol alcohol; and 2-isopropyl-5—2.08%. The remaining compounds were detected in amounts of less than 2.0%. Tests of seven cosmetic compositions developed on the basis of plant extracts and salt-containing raw materials revealed that three samples had a moisturizing effect. Launching the production of cosmetic products in the Aral region will not only reduce social tensions but also significantly improve the environmental situation in the region.

Assessment of the Anti-Inflammatory, Antibacterial and Anti-Aging Properties and Possible Use on the Skin of Hydrogels Containing Epilobium angustifolium L. Extracts

Epilobium angustifolium L. is an ethnomedicinal plant known as a medicinal plant in many regions of the world, among others, in various skin diseases. Despite the great interest in this plant, there are still few reports of biological activity of ready-made dermatological or cosmetical preparations containing the E. angustifolium extracts. The antioxidant, anti-ageing, anti-inflammatory, antibacterial properties and toxicity, wound healing, and skin permeation of topical hydrogels containing E. angustifolium extracts (HEas) was assessed. First, the plant extracts were prepared using three solvents: 70% (v/v) ethanol, 70% (v/v) isopropanol and water, next by preparing hydrogels witch by dry extracts (HEa-EtOH), (HEa-iPrOH) and (HEa-WA), respectively. Finally, the content of selected phenolic acids in the HEas was evaluated by high-performance liquid chromatography (HPLC). All the HEas were characterized by high antioxidant activity. The most increased antibacterial activity was observed for a strain of Streptococcus pneumoniae ATCC 49619, Escherichia coli, Enterococcus faecalis ATCC 29212, Enterococcus faecium, Sarcina lutea ATCC 9341 and Bacillus pseudomycoides, while the strains of Streptococcus epidermidis, Bacillus subtilis, and Staphylococcus aureus were the least sensitive. All the HEas showed a reduction in the activity of lipoxygenase enzymes, proteases, and inhibition of protein denaturation. The HEa-EtOH and HEa-iPrOH also enhanced the wound healing activity of HDF cells. Additionally, in vitro penetration studies were performed using the Franz diffusion cells. These studies showed that the active ingredients contained in E. angustifolium penetrate through human skin and accumulate in it. Furthermore, the hydrogels containing E. angustifolium extracts showed a broad spectrum of activity. Therefore, they can be considered as an interesting alternative for dermatologic and cosmetic preparations.

Extraction of Bioactive Components from Chamaenerion angustifolium (L.) Scop. with Choline Chloride and Organic Acids Natural Deep Eutectic Solvents

Chamaenerion angustifolium (L.) Scop. (fireweed) is a perennial herbaceous plant of the Onagraceae family widely used in folk and scientific medicine. It is a promising source of bioactive components. One of the modern trends in extraction is the use of natural deep eutectic solvents (NADESs) combined with ultrasound-assisted extraction (UAE). However, works devoted to the extraction of biologically active substances from C. angustifolium using NADESs are scarce. The aim of this work is a comprehensive study of UAE of bioactive components from C. angustifolium using NADESs based on choline chloride and malonic, malic, tartaric, and citric acids. The antioxidative properties, total phenols, and flavonoids content were estimated for NADES-based extracts. The reference solvents were water and 90% v/v ethanol. Volatile extracted components were identified using GC-MS. The kinetics of the UAE were studied at 45 °C for 20–180 min with water added to 30 wt% NADES. The power of the ultrasound was 120 W, and the frequency was 40 kHz. It was found that NADES choline chloride + citric acid is more effective for the extraction of bioactive components. For this, NADES UAE conditions were optimized following a Box–Behnken design of the experiment and a response surface methodology. The temperature ranged from 30 to 60 °C, the time of extraction ranged from 20 to 60, and the addition of water ranged from 30 to 70 wt%. We established the optimal extraction conditions: temperature 58 °C, time of extraction 35 min, and 70 wt% water. The obtained results expand the knowledge about the use of NADES for the extraction of biologically active compounds from cheap and available plant raw materials.

Epilobium angustifolium L. as a Potential Herbal Component of Topical Products for Skin Care and Treatment-A Review

Epilobium angustifolium L. (EA) has been used as a topical agent since ancient times. There has been an increasing interest in applying EA as a raw material used topically in recent years. However, in the literature, there are not many reports on the comprehensive application of this plant to skin care and treatment. EA contains many valuable secondary metabolites, which determine antioxidant, anti-inflammatory, anti-aging, and antiproliferative activity effects. One of the most important active compounds found in EA is oenothein B (OeB), which increases the level of ROS and protects cells from oxidative damage. OeB also influences wound healing and reduces inflammation by strongly inhibiting hyaluronidase enzymes and inhibiting COX-1 and COX-2 cyclooxygenases. Other compounds that play a key role in the context of application to the skin are flavonoids, which inhibit collagenase and hyaluronidase enzymes, showing anti-aging and anti-inflammatory properties. While terpenes in EA play an important role in fighting bacterial skin infections, causing, among other things cell membrane, permeability increase as well as the modification of the lipid profiles and the alteration of the adhesion of the pathogen to the animal cells. The available scientific information on the biological potential of natural compounds can be the basis for the wider use of EA in skin care and treatment. The aim of the article is to review the existing literature on the dermocosmetic use of E. angustifolium.

Antimicrobial Activity and Wound-Healing Capacity of Birch, Beech and Larch Bark Extracts

Bark is a major by-product of woodworking industries. The contents of several wood species are known to harbor antimicrobial, antiviral, anti-inflammatory and wound-healing capacities. The aim of this work was to identify beneficial properties of Austrian larch, birch and beech bark extracts for their potential usage as additives or active ingredients in dermatological applications. Bacterial agar diffusion assay and resazurin-based broth microdilution assay were used to evaluate anti-bacterial activity. To gain more insight into the cellular response to bark extracts, viability-, scratch-assays and ELISAs were performed. Birch and beech extracts showed strong antimicrobial activities against Gram-positive bacteria, including Cutibacterium acnes, Staphylococcus epidermidis and MRSA. Wound closure was enhanced with birch and beech extracts as compared to controls in the scratch-assays. Whereas beneficial properties of birch bark components have previously been described, the similar effects of beech extracts are novel. The combined positive effect on wound-healing and antimicrobial activity has great potential for the treatment of various skin diseases, including acne in future dermal applications.

Biological Activity of an Epilobium angustifolium L. (Fireweed) Infusion after In Vitro Digestion

The biological activity of an in vitro digested infusion of Epilobium angustifolium (fireweed) was examined in a model system of intestinal epithelial and colon cancer tissues. The content of selected phenolic compounds in the digested aqueous extract of fireweed was determined using HPLC-ESI-QTOF-MS/MS. Biological activity was examined using the human colon adenocarcinoma cell lines HT-29 and CaCo-2 and the human colon epithelial cell line CCD 841 CoTr. Cytotoxicity was assessed by an MTT assay, a Neutral Red uptake assay, May-Grünwald-Giemsa staining, and a label-free Electric Cell-Substrate Impedance Sensing cytotoxicity assay. The effect of the infusion on the growth of selected intestinal bacteria was also examined. The extract inhibited the growth of intestinal cancer cells HT-29. This effect can be attributed to the activity of quercetin and kaempferol, which were the most abundant phenolic compounds found in the extract after in vitro digestion. The cytotoxicity of the fireweed infusion was dose-dependent. The highest decrease in proliferation (by almost 80%) compared to the control was observed in HT-29 line treated with the extract at a concentration of 250 μg/mL. The fireweed infusion did not affect the growth of beneficial intestinal bacteria, but it did significantly inhibit E. coli. The cytotoxic effect of the fireweed extract indicates that it does not lose its biological activity after in vitro digestion. It can be concluded that the fireweed infusion has the potential to be used as a supporting agent in colon cancer therapy.

Epilobium angustifolium L. Essential Oil-Biological Activity and Enhancement of the Skin Penetration of Drugs-In Vitro Study

Epilobium angustifolium L. is a popular medicinal plant found in many regions of the world. This plant contains small amounts of essential oil whose composition and properties have not been extensively investigated. There are few reports in the literature on the antioxidant and antifungal properties of this essential oil and the possibility of applying it as a potential promoter of the skin penetration of drugs. The essential oil was obtained by distillation using a Clavenger type apparatus. The chemical composition was analyzed by the GC-MS method. The major active compounds of E. angustifolium L. essential oil (EOEa) were terpenes, including α-caryophyllene oxide, eucalyptol, β-linalool, camphor, (S)-carvone, and β-caryophyllene. The analyzed essential oil was also characterized by antioxidant activity amounting to 78% RSA (Radical Scavenging Activity). Antifungal activity against the strains Aspergillus niger, A. ochraceus, A. parasiticum, and Penicillium cyclopium was also determined. The largest inhibition zone was observed for strains from the Aspergillus group. The EOEa enhanced the percutaneous penetration of ibuprofen and lidocaine. After a 24 h test, the content of terpene in the skin and the acceptor fluid was examined. It has been shown that the main compounds contained in the essential oil do not penetrate through the skin, but accumulate in it. Additionally, FTIR-ATR analysis showed a disturbance of the stratum corneum (SC) lipids caused by the essential oil application. Due to its rich composition and high biological activity, EOEa may be a potential candidate to be applied, for example, in the pharmaceutical or cosmetic industries. Moreover, due to the reaction of the essential oil components with SC lipids, the EOEa could be an effective permeation enhancer of topically applied hydrophilic and lipophilic drugs.

Dermal Drug Delivery of Phytochemicals with Phenolic Structure via Lipid-Based Nanotechnologies

Phenolic compounds are a large, heterogeneous group of secondary metabolites found in various plants and herbal substances. From the perspective of dermatology, the most important benefits for human health are their pharmacological effects on oxidation processes, inflammation, vascular pathology, immune response, precancerous and oncological lesions or formations, and microbial growth. Because the nature of phenolic compounds is designed to fit the phytochemical needs of plants and not the biopharmaceutical requirements for a specific route of delivery (dermal or other), their utilization in cutaneous formulations sets challenges to drug development. These are encountered often due to insufficient water solubility, high molecular weight and low permeation and/or high reactivity (inherent for the set of representatives) and subsequent chemical/photochemical instability and ionizability. The inclusion of phenolic phytochemicals in lipid-based nanocarriers (such as nanoemulsions, liposomes and solid lipid nanoparticles) is so far recognized as a strategic physico-chemical approach to improve their in situ stability and introduction to the skin barriers, with a view to enhance bioavailability and therapeutic potency. This current review is focused on recent advances and achievements in this area.

Natural Products and Skin Diseases

The skin is the largest multifunctional organ in the human body, serving as an excellent barrier against chemical and biological hazards [...].

The Effect of Cream and Gel Vehicles on the Percutaneous Absorption and Skin Retention of a New Eugenol Derivative With Antioxidant Activity

The effect of cream and gel vehicles containing clove water on skin permeability was compared for a new eugenol derivative (eugenyl dichloroacetate-EDChA) with antioxidant activity. In vitro permeation experiments were conducted in a Franz cell with porcine skin. The cumulative mass and skin accumulation of EDChA were investigated and compared. The antioxidative capacity of the studied vehicles was determined by using the diphenylpicrylhydrazyl (DPPH) free radical reduction method. The antioxidant activity (evaluated with DPPH, ABTS, and the Folin-Ciocalteu methods) of the fluid that penetrated through the pig skin and of the fluid obtained after the skin extraction, were also determined. For comparison, eugenol was also tested. The results of this work could contribute to the development of vehicles with antioxidant potential estimated after 24 h of conducting the experiment, which indicates long-term protection against reactive oxygen species (ROS) in the deeper layers of the skin. The waste water from the clove buds steam distillation -contains several valuable biologically active compounds, and its use is environmentally friendly. We observed that gel vehicles were the best enhancer of skin permeation for both eugenol and its derivative. In most cases, -similar cumulative masses of eugenol and its ester were found in the acceptor fluid. The accumulation of EDChA was higher for cream vehicles in relation to the parent eugenol when applied onto the skin. The greatest amounts of eugenol were accumulated in the skin when these compounds were used in gel vehicles.

Bacterial Cellulose Membrane Containing Epilobium angustifolium L. Extract as a Promising Material for the Topical Delivery of Antioxidants to the Skin

Bacterial cellulose membranes (BCs) are becoming useful as a drug delivery system to the skin. However, there are very few reports on their application of plant substances to the skin. Komagataeibacter xylinus was used for the production of bacterial cellulose (BC). The BC containing 5% and 10% ethanolic extract of Epilobium angustifolium (FEE) (BC-5%FEE and BC-10%FEE, respectively) were prepared. Their mechanical, structural, and antioxidant properties, as well as phenolic acid content, were evaluated. The bioavailability of BC-FESs using mouse L929 fibroblasts as model cells was tested. Moreover, In Vitro penetration through the pigskin of the selected phenolic acids contained in FEE and their accumulation in the skin after topical application of BC-FEEs was examined. The BC-FEEs were characterized by antioxidant activity. The BC-5% FEE showed relatively low toxicity to healthy mouse fibroblasts. Gallic acid (GA), chlorogenic acid (ChA), 3,4-dihydroxybenzoic acid (3,4-DHB), 4-hydroxybenzoic acid (4-HB), 3-hydroxybenzoic acid (3-HB), and caffeic acid (CA) found in FEE were also identified in the membranes. After topical application of the membranes to the pigskin penetration of some phenolic acid and other antioxidants through the skin as well as their accumulation in the skin was observed. The bacterial cellulose membrane loaded by plant extract may be an interesting solution for topical antioxidant delivery to the skin.

Epilobium angustifolium L. Extracts as Valuable Ingredients in Cosmetic and Dermatological Products

Epilobium angustifolium L. is a popular and well-known medicinal plant. In this study, an attempt to evaluate the possibility of using this plant in preparations for the care and treatment of skin diseases was made. The antioxidant, antiaging and anti-inflammatory properties of ethanolic extracts from Epilobium angustifolium (FEE) were assessed. Qualitative and quantitative evaluation of extracts chemically composition was performed by gas chromatography with mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC). The total polyphenol content (TPC) of biologically active compounds, such as the total content of polyphenols (TPC), flavonoids (TFC), and assimilation pigments, as well as selected phenolic acids, was assessed. FEE was evaluated for their anti-inflammatory and antiaging properties, achieving 68% inhibition of lipoxygenase activity, 60% of collagenase and 49% of elastase. FEE also showed high antioxidant activity, reaching to 87% of free radical scavenging using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 59% using 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). Additionally, in vitro penetration studies were performed using two vehicles, i.e., a hydrogel and an emulsion containing FEE. These studies showed that the active ingredients contained in FEE penetrate through human skin and accumulate in it. The obtained results indicate that E. angustifolium may be an interesting plant material to be applied as a component of cosmetic and dermatological preparations with antiaging and anti-inflammatory properties.

Enhancement of the Antioxidant and Skin Permeation Properties of Betulin and Its Derivatives

This study investigated the antioxidant activity DPPH, ABTS, and Folin-Ciocalteu methods of betulin (compound 1) and its derivatives (compounds 2-11). Skin permeability and accumulation associated with compounds 1 and 8 were also examined. Identification of the obtained products (compound 2-11) and betulin isolated from plant material was based on the analysis of 1H- NMR and 13C-NMR spectra. The partition coefficient was calculated to determine the lipophilicity of all compounds. In the next stage, the penetration through pig skin and its accumulation in the skin were evaluated of ethanol vehicles containing compound 8 (at a concentration of 0.226 mmol/dm3), which was characterized by the highest antioxidant activity. For comparison, penetration studies of betulin itself were also carried out. Poor solubility and the bioavailability of pure compounds are major constraints in combination therapy. However, we observed that the ethanol vehicle was an enhancer of skin permeation for both the initial betulin and compound 8. The betulin 8 derivative showed increased permeability through biological membranes compared to the parent betulin. The paper presents the transformation of polycyclic compounds to produce novel derivatives with marked antioxidant activities and as valuable intermediates for the pharmaceutical industry. Moreover, the compounds contained in the vehicles, due to their mechanism of action, can have a beneficial effect on the balance between oxidants and antioxidants in the body, minimizing the effects of oxidative stress. The results of this work may contribute to knowledge regarding vehicles with antioxidant potential. The use of vehicles for this type of research is therefore justified.