Antibacterial Activity of Medicinal Plants and Their Constituents in the Context of Skin and Wound Infections, Considering European Legislation and Folk Medicine-A Review

Liposome encapsulating pine bark extract in Nile tilapia: Targeting interrelated immune and antioxidant defense to combat coinfection with Aeromonas hydrophila and Enterococcus faecalis

Application of smart delivery systems for encapsulation of natural ingredients provides novel avenues and is being frequently developed. Thus, we aimed to highlight the effects of cyclosome liposomal pine bark extract (CL-PBE) on Nile tilapia growth, immunomodulation, antioxidant capacity and resistance against coinfection with Aeromonas hydrophila and Enterococcus faecalis and their associated virulence genes. The experiment was conducted on four fish groups receiving a control diet (control) along with three baseline meals supplemented with 200, 400 and 600 mg/kg diet of CL-PBE (CL-PBE 200, 400 and 600, respectively). At the end of the 12-weeks feeding trial, the tilapias were intraperitoneally challenged with virulent A. hydrophila strain and five days later, E. faecalis challenge was carried out. The results revealed that tilapias fed diets fortified with CL-PBE displayed significantly enhanced growth rate and feed conversion ratio in a dose-dependent manner. Moreover, we demonstrated that CL-PBE had potent antioxidant property presented by modulation of several markers of oxidative stress; substantial reductions in reactive oxygen species, hydrogen peroxide and malondialdehyde levels, an elevation in total antioxidant capacity and boosting glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) activities in fish serum and muscle tissues. This was also correlated with augmenting the expression of CAT, SOD, GSH-Px, Nrf2 and caspase-1 genes alongside reducing those of COX-2, HSP70 and iNOS genes in response to CL-PBE. Our data demonstrated that CL-PBE fortification counteracted the overly pronounced inflammatory response-mediated induction of IL-1β, TNF-α, MHCII and TLR2 genes at the transcriptional levels post coinfection together with promotion in MUC2 and IL-10 genes expression. Notably, our findings displayed optimal well-functioning fish immune system post dietary supplementation of CL-PBE for the protection against coinfection with A. hydrophila and E. faecalis. This was evident from the decline of their counts and hence encompassing the capacity to reduce cumulative mortality percentage in conjunction with interference with their virulence via the significant downregulatory effects of CL-PBE on E. faecalis esp and gelE and A. hydrophila act and fla virulence genes. Taken together, our study strongly suggested dietary inclusion of CL-PBE for Nile tilapias with superior growth performance and significant economic benefits coupled with potent stimulatory effects on antioxidant capacity and immune response expediting our detailed understanding of how coinfection with A. hydrophila and E. faecalis was controlled.

Synergistic antibacterial activity of baicalin in combination with oxacillin sodium against methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) poses a challenge for clinical treatment and combining antibiotics with other agents might be a promising strategy to overcome this challenge. This study explored the synergistic antibacterial activity of baicalin (traditional Chinese medicine extract) and the narrow-spectrum beta-lactam antibiotic oxacillin sodium, both of which are poorly active against MRSA in vitro. The combination of baicalin and oxacillin sodium showed a synergistic effect with a fractional inhibitory concentration index of 0.5. Mechanistically, the supplementation of baicalin increased the permeability of bacterial cell walls and cell membranes, enhancing oxacillin sodium entry and bactericidal action. The combination of baicalin and oxacillin sodium also significantly inhibited MRSA USA300 biofilm formation by further reducing polysaccharide intercellular adhesion production. Therefore, the combination of baicalin and oxacillin sodium offers a new therapeutic option for addressing clinical MRSA resistance. Further studies, including clinical trials, will be required to validate the observed in vitro results.

Extracts of Achillea millefolium L. inhibited biofilms and biofilm-related virulence factors of pathogenic bacteria isolated from wounds

Biofilm is a surface-attached community of bacterial cells implicated in the pathogenesis of chronic infections and is highly resistant to antibiotics. New alternatives for controlling bacterial infections have been proposed focusing on the therapeutic properties of medicinal plants. Achillea millefollium (Yarrow) is a widespread plant species that is widely used in traditional medicine, especially for wound healing. Therefore, the purpose of this study was to examine the antibiofilm activity of A. millefolium ethanol, acetone, and ethyl acetate extracts on biofilms of Staphylococcus aureus, Proteus spp. and Pseudomonas aeruginosa strains originating from human wounds. Additionally, the effects of the tested extracts on auto-aggregation, cell surface hydrophobicity, and bacterial motility were evaluated. Phytochemical analysis included FT-IR spectroscopy and spectrophotometric quantification of phenolic compound contents was performed. In a test with crystal violet, the extracts strongly inhibited initial cell attachment and biofilm formation, but the effects on mature biofilms were weaker. The effects were dose- and strain-dependent, which was confirmed by fluorescence microscopy. The acetone extract showed the strongest antibiofilm activity. Biofilms of S. aureus S3 and S2 clinical strains were the most susceptible (inhibition of ≥76 % and ≥72 % at all tested concentrations, respectively). The highest concentration of total flavonoids was measured in the acetone extract (100.01 ± 3.13 mg RUE/g). Additionally, the extracts reduced bacterial auto-aggregation, swimming and swarming motility of some strains but did not disturb bacterial cell hydrophobicity. These results suggest that A. millefolium extracts have potential roles as new antibiofilm agents against human pathogenic bacteria.

Frequency-dependent dielectric spectroscopic analysis on phytochemical and antioxidant activities in Radix Glycyrrhizae extract

Radix Glycyrrhizae, the dried roots of the Glycyrrhiza glabra plant, is a popular Chinese herbal medicine known for its various health benefits. It is particularly effective in relieving respiratory problems like coughs, sore throats, bronchitis, and asthma. However, there is limited research on the electrical properties of Radix Glycyrrhizae, likely due to its complex composition of phytochemical and antioxidant activities. This research aims to investigate the potential of these active biological compounds and understand their electrochemical properties. In this study, High-Performance Liquid Chromatography (HPLC) analysis revealed that Radix Glycyrrhizae decoction contains significant amounts of flavonoids and saponins, compounds known for their health benefits and therapeutic effects. Further analysis using Fourier Transform Infrared Spectroscopy (FTIR) identified several functional groups, including phenols, alcohols, alkynes, alkenes, ethers, and glycosides, which contribute to the plant's medicinal potential and affect the impedance and dielectric properties of the extract. The antioxidant activity of Radix Glycyrrhizae decoction was also evaluated using DPPH assays, showing similar radical scavenging activity to gallic acid. Dielectric and impedance measurement of Radix Glycyrrhizae extract were performed using an Agilent vector network analyzer and a Hioki impedance analyzer. The dielectric constant measured was consistent across both analyzers. However, the loss factor showed different trends: the vector network analyzer indicated a decrease in the loss factor with increasing frequency in the range of 5 MHz-20 GHz, while the impedance analyzer showed the opposite trend in the frequency range of 4 Hz-5 MHz.

The role of current synthetic and possible plant and marine phytochemical compounds in the treatment of acne

Acne is a long-standing skin condition characterized by plugged hair follicles due to the accumulation of dead skin cells, sebum, and Propionibacterium acnes (P. acnes) bacteria, causing inflammation, and the formation of pimples or lesions. Acne was recognized in the ancient times by the ancient Egyptians, Greeks, and Romans. Since ancient times, folk medicine from different cultures have comprised herbal and natural products for the treatment of acne. Current acne medications include antibiotics, keratolytics, corticosteroids, in addition to hormonal therapy for women. However, these conventional drugs can cause some serious side effects. And therefore, seeking new safe treatment options from natural sources is essential. Plants can be a potential source of medicinal phytochemicals which can be pharmacologically active as antibacterial, antioxidant, anti-inflammatory, keratolytic and sebum-reducing. Organic acids, obtained from natural sources, are commonly used as keratolytics in dermatology and cosmetology. Most of the promising phytochemicals in acne treatment belong to terpenes, terpenoids, flavonoids, alkaloids, phenolic compounds, saponins, tannins, and essential oils. These can be extracted from leaves, bark, roots, rhizomes, seeds, and fruits of plants and may be incorporated in different dosage forms to facilitate their penetration through the skin. Additionally, medicinal compounds from marine sources can also contribute to acne treatment. This review will discuss the pathogenesis, types and consequences of acne, side effects of conventional treatment, current possible treatment options from natural sources obtained from research and folk medicine and possible applied dosage forms.

Potential Surviving Effect of Cleome droserifolia Extract against Systemic Staphylococcus aureus Infection: Investigation of the Chemical Content of the Plant

The increasing rates of morbidity and mortality owing to bacterial infections, particularly Staphylococcus aureus have necessitated finding solutions to face this issue. Thus, we elucidated the phytochemical constituents and antibacterial potential of Cleome droserifolia extract (CDE). Using LC-ESI-MS/MS, the main phytoconstituents of CDE were explored, which were kaempferol-3,7-O-bis-alpha-L-rhamnoside, isorhamnetin, cyanidin-3-glucoside, kaempferide, kaempferol-3-O-alpha-L-rhamnoside, caffeic acid, isoquercitrin, quinic acid, isocitrate, mannitol, apigenin, acacetin, and naringenin. The CDE exerted an antibacterial action on S. aureus isolates with minimum inhibitory concentrations ranging from 128 to 512 µg/mL. Also, CDE exhibited antibiofilm action using a crystal violet assay. A scanning electron microscope was employed to illuminate the effect of CDE on biofilm formation, and it considerably diminished S. aureus cell number in the biofilm. Moreover, qRT-PCR was performed to study the effect of CDE on biofilm gene expression (cna, fnbA, and icaA). The CDE revealed a downregulating effect on the studied biofilm genes in 43.48% of S. aureus isolates. Regarding the in vivo model, CDE significantly decreased the S. aureus burden in the liver and spleen of CDE-treated mice. Also, it significantly improved the mice's survival and substantially decreased the inflammatory markers (interleukin one beta and interleukin six) in the studied tissues. Furthermore, CDE has improved the histology and tumor necrosis factor alpha immunohistochemistry in the liver and spleen of the CDE-treated group. Thus, CDE could be considered a promising candidate for future antimicrobial drug discovery studies.

Interactions of plumbagin with five common antibiotics against Staphylococcus aureus in vitro

Staphylococcus aureus is the main culprit, causing a variety of severe clinical infections. At the same time, clinics are also facing the severe situation of antibiotic resistance. Therefore, effective strategies to address this problem may include expanding the antimicrobial spectrum by exploring alternative sources of drugs or delaying the development of antibiotic resistance through combination therapy so that existing antibiotics can continue to be used. Plumbagin (PLU) is a phytochemical that exhibits antibacterial activity. In the present study, we investigated the in vitro antibacterial activity of PLU. We selected five antibiotics with different mechanisms and inhibitory activities against S. aureus to explore their interaction with the combination of PLU. The interaction of combinations was evaluated by the Bliss independent model and visualized through response surface analysis. PLU exhibited potent antibacterial activity, with half maximal inhibitory concentration (IC50) and minimum inhibitory concentration (MIC) values against S. aureus of 1.73 μg/mL and 4 μg/mL, respectively. Synergism was observed when PLU was combined with nitrofurantoin (NIT), ciprofloxacin (CPR), mecillinam (MEC), and chloramphenicol (CHL). The indifference of the trimethoprim (TMP)-PLU pairing was demonstrated across the entire dose-response matrix, but significant synergy was observed within a specific dose region. In addition, no antagonistic interactions were indicated. Overall, PLU is not only a promising antimicrobial agent but also has the potential to enhance the growth-inhibitory activity of some antibiotics against S. aureus, and the use of the interaction landscape, along with the dose-response matrix, for analyzing and quantifying combination results represents an improved approach to comprehending antibacterial combinations.

An Overview of Biofilm-Associated Infections and the Role of Phytochemicals and Nanomaterials in Their Control and Prevention

Biofilm formation is considered one of the primary virulence mechanisms in Gram-positive and Gram-negative pathogenic species, particularly those responsible for chronic infections and promoting bacterial survival within the host. In recent years, there has been a growing interest in discovering new compounds capable of inhibiting biofilm formation. This is considered a promising antivirulence strategy that could potentially overcome antibiotic resistance issues. Effective antibiofilm agents should possess distinctive properties. They should be structurally unique, enable easy entry into cells, influence quorum sensing signaling, and synergize with other antibacterial agents. Many of these properties are found in both natural systems that are isolated from plants and in synthetic systems like nanoparticles and nanocomposites. In this review, we discuss the clinical nature of biofilm-associated infections and some of the mechanisms associated with their antibiotic tolerance. We focus on the advantages and efficacy of various natural and synthetic compounds as a new therapeutic approach to control bacterial biofilms and address multidrug resistance in bacteria.

Effects of Calamintha incana (Sm.) Helder Ethanolic Extract on the mRNA Expression of Drug-metabolizing cyp450s in the Mouse Livers

BACKGROUND

Alteration in the expression and activity of drug-metabolizing enzymes (DMEs) can alter the pharmacokinetics and hence the response of the drug. Some chemicals found in herbs and fruits affect the expression of DMEs. Calamintha incana is commonly used in Middle Eastern Arabic countries. There is no report regarding the influence of Calamintha incana on the hepatic expression of DMEs.

AIMS

The current investigation aimed to investigate the effect of Calamintha incana consumption on the mRNA expression of major hepatic drug-metabolizing cytochrome (cyp) P450 genes in mice.

METHODS

The chemical composition of the ethanoic extract was analyzed using liquid chromatography/ mass spectrometry. Then, 21 BALB/c mice were used for the in vivo experiment. The mice were divided into three groups, each consisting of seven mice. The first group (low-dose group) was treated with 41.6 mg/kg of Calamintha incana extract and the second group was administered the high-dose (125 mg/kg) of the extract for one month. The mice in the third "control" group administrated the vehicle 20% polyethylene glycol 200. Then, the expression of cyp3a11, cyp2c29, cyp2d9, and cyp1a1 was analyzed using the real-time polymerase chain reaction. The relative liver weights of the mice and the hepatic pathohistological alterations were assessed.

RESULTS

The ethanolic extract of Calamintha incana contained 27 phytochemical compounds. The most abundant compounds were linolenic acid, myristic acid, and p-cymene. It was found that the low dose of Calamintha incana extract upregulated significantly (P < 0.05) the expression of cyp3a11 by more than ten folds in the liver of treated mice. Furthermore, the histological analysis showed that low- and high-dose administration of the C. incana did not cause pathological alterations.

CONCLUSION

It can be concluded from these findings that consumption of low doses of Calamintha incana upregulated the mRNA expression of mouse cyp3a11 without causing histopathological alterations in the livers. Further studies are needed to determine the influence of Calamintha incana on the pharmacokinetics and response of drugs metabolized by cyp3a11.

Bioassay-Guided Assessment of Antioxidative, Anti-Inflammatory and Antimicrobial Activities of Extracts from Medicinal Plants via High-Performance Thin-Layer Chromatography

Natural products and their analogues have contributed significantly to treatment options, especially for anti-inflammatory and infectious diseases. Thus, the primary objective of this work was to compare the bioactivity profiles of selected medicinal plants that are historically used in folk medicine to treat inflammation and infections in the body. Chemical HPTLC fingerprinting was used to assess antioxidant, phenolic and flavonoid content, while bioassay-guided HPTLC was used to detect compounds with the highest antibacterial and anti-inflammatory activities. The results of this study showed that green tea leaf, walnut leaf, St. John's wort herb, wild thyme herb, European goldenrod herb, chamomile flower, and immortelle flower extracts were strong radical scavengers. Green tea and nettle extracts were the most active extracts against E. coli, while calendula flower extract showed significant potency against S. aureus. Furthermore, green tea, greater celandine, and fumitory extracts exhibited pronounced potential in suppressing COX-1 activity. The bioactive compounds from the green tea extract, as the most bioactive, were isolated by preparative thin-layer chromatography and characterized with their FTIR spectra. Although earlier studies have related green tea's anti-inflammatory properties to the presence of catechins, particularly epigallocatechin-3-gallate, the FTIR spectrum of the compound from the most intense bioactive zone showed the strongest anti-inflammatory activity can be attributed to amino acids and heterocyclic compounds. As expected, antibacterial activity in extracts was related to fatty acids and monoglycerides.

Plant Extracts as Skin Care and Therapeutic Agents

Natural ingredients have been used for centuries for skin treatment and care. Interest in the health effects of plants has recently increased due to their safety and applicability in the formulation of pharmaceuticals and cosmetics. Long-known plant materials as well as newly discovered ones are increasingly being used in natural products of plant origin. This review highlights the beneficial effects of plants and plant constituents on the skin, including moisturizing (e.g., Cannabis sativa, Hydrangea serrata, Pradosia mutisii and Carthamus tinctorius), anti-aging (e.g., Aegopodium podagraria, Euphorbia characias, Premna odorata and Warburgia salutaris), antimicrobial (e.g., Betula pendula and Epilobium angustifolium), antioxidant (e.g., Kadsura coccinea, Rosmarinus officinalis, Rubus idaeus and Spatholobus suberectus), anti-inflammatory (e.g., Antidesma thwaitesianum, Helianthus annuus, Oenanthe javanica, Penthorum chinense, Ranunculus bulumei and Zanthoxylum bungeanum), regenerative (e.g., Aloe vera, Angelica polymorpha, Digitaria ciliaris, Glycyrrihza glabra and Marantodes pumilum), wound healing (e.g., Agrimonia eupatoria, Astragalus floccosus, Bursera morelensis, Jatropha neopauciflora and Sapindus mukorossi), photoprotective (e.g., Astragalus gombiformis, Calea fruticose, Euphorbia characias and Posoqueria latifolia) and anti-tyrosinase activity (e.g., Aerva lanata, Bruguiera gymnorhiza, Dodonaea viscosa, Lonicera japonica and Schisandra chinensis), as well as their role as excipients in cosmetics (coloring (e.g., Beta vulgaris, Centaurea cyanus, Hibiscus sabdariffa and Rubia tinctiorum), protective and aromatic agents (e.g., Hyssopus officinalis, Melaleuca alternifolia, Pelargonium graveolens and Verbena officinalis)).

In Vitro Synergistic Inhibitory Effects of Plant Extract Combinations on Bacterial Growth of Methicillin-Resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common pathogens of healthcare-associated infections. Medicinal plants have long been used in the traditional treatment of diseases or syndromes worldwide. Combined use of plant extracts could improve the effectiveness of pharmacological action by obtaining synergism, acting on multiple targets simultaneously, reducing the doses of individual components, and minimizing side effects. We aimed to investigate the synergistic inhibitory effects of selected medicinal plants (Caesalpinia sappan L. (CS), Glycyrrhiza uralensis Fisch. (GU), Sanguisorba officinalis L. (SO), and Uncaria gambir Roxb. (UG)) on the bacterial growth of MRSA and its clinical isolates. SO and UG extracts generated the best synergistic interaction as adjudged by checkerboard synergy assays. MICs of the individual extracts decreased 4-fold from 250 to 62.5 μg/mL, respectively. The SO + UG combination was further evaluated for its effects on bacterial growth inhibition, minimum bactericidal/inhibitory concentration (MBC/MIC) ratio, and time-kill kinetics. The results indicate that the SO + UG combination synergistically inhibited the bacterial growth of MRSA strains with bactericidal effects. SO + UG combination also exhibited more potent effects against clinical isolates. In multistep resistance selection experiments, both standard and isolates of MRSA showed no resistance to the SO + UG combination even after repeated exposure over fourteen passages. Our data suggest that using plant extract combinations could be a potential strategy to treat MRSA infections.

Comparative Study of Cytotoxicity and Antioxidant, Anti-Aging and Antibacterial Properties of Unfermented and Fermented Extract of Cornus mas L

Due to the high demand for products that can help treat various skin conditions, the interest in plant extracts, which are a valuable source of phytochemicals, is constantly growing. In this work, the properties of extracts and ferments from Cornus mas L. and their potential use in cosmetic products were compared. For this purpose, their composition, antioxidant properties and cytotoxicity against skin cells, keratinocytes and fibroblasts were assessed in vitro. In addition, the ability to inhibit the activity of collagenase and elastase was compared, which enabled the assessment of their potential to inhibit skin aging. Microbiological analyses carried out on different bacterial strains were made in order to compare their antibacterial properties. The conducted analyses showed that both dogwood extract and ferment have antioxidant and anti-aging properties. In addition, they can have a positive effect on the viability of keratinocytes and fibroblasts and inhibit the proliferation of various pathogenic bacteria, which indicates their great potential as ingredients in skin care preparations. The stronger activity of the ferment compared to the extract indicates the legitimacy of carrying out the fermentation process of plant raw materials using kombucha in order to obtain valuable products for the cosmetics industry.

Medicinal Plants of the Flora of Kazakhstan Used in the Treatment of Skin Diseases

The skin shows the physiological condition of the body's organs and systems that prevent infections and physical damage. Throughout the ages, in folk medicine, phytotherapy was considered a primary form of treatment in all countries, including Kazakhstan, due to the abundance and availability of plant-based remedies. This paper discusses several medicinal plants that are traditionally used in the treatment of skin diseases in the Republic of Kazakhstan. The chemical composition of these plants was analyzed, with a particular focus on the biologically active basic compounds responsible for their therapeutic efficiency in treating skin ailments.

Molecular Mechanisms of Regulation of Root Development by Plant Peptides

Peptides perform many functions, participating in the regulation of cell differentiation, regulating plant growth and development, and also involved in the response to stress factors and in antimicrobial defense. Peptides are an important class biomolecules for intercellular communication and in the transmission of various signals. The intercellular communication system based on the ligand-receptor bond is one of the most important molecular bases for creating complex multicellular organisms. Peptide-mediated intercellular communication plays a critical role in the coordination and determination of cellular functions in plants. The intercellular communication system based on the receptor-ligand is one of the most important molecular foundations for creating complex multicellular organisms. Peptide-mediated intercellular communication plays a critical role in the coordination and determination of cellular functions in plants. The identification of peptide hormones, their interaction with receptors, and the molecular mechanisms of peptide functioning are important for understanding the mechanisms of both intercellular communications and for regulating plant development. In this review, we drew attention to some peptides involved in the regulation of root development, which implement this regulation by the mechanism of a negative feedback loop.

Bacterial resistance to antibacterial agents: Mechanisms, control strategies, and implications for global health

The spread of bacterial drug resistance has posed a severe threat to public health globally. Here, we cover bacterial resistance to current antibacterial drugs, including traditional herbal medicines, conventional antibiotics, and antimicrobial peptides. We summarize the influence of bacterial drug resistance on global health and its economic burden while highlighting the resistance mechanisms developed by bacteria. Based on the One Health concept, we propose 4A strategies to combat bacterial resistance, including prudent Application of antibacterial agents, Administration, Assays, and Alternatives to antibiotics. Finally, we identify several opportunities and unsolved questions warranting future exploration for combating bacterial resistance, such as predicting genetic bacterial resistance through the use of more effective techniques, surveying both genetic determinants of bacterial resistance and the transmission dynamics of antibiotic resistance genes (ARGs).

Antioxidative and Antimicrobial Evaluation of Bark Extracts from Common European Trees in Light of Dermal Applications

Plant species have developed effective defense strategies for colonizing diverse habitats and protecting themselves from numerous attacks from a wide range of organisms, including insects, vertebrates, fungi, and bacteria. The bark of trees in particular constitutes a number of components that protect against unwanted intruders. This review focuses on the antioxidative, dermal immunomodulatory, and antimicrobial properties of bark extracts from European common temperate trees in light of various skin pathogens, wound healing, and the maintenance of skin health. The sustainability aspect, achieved by utilizing the bark, which is considered a byproduct in the forest industry, is addressed, as are various extraction methods applied to retrieve extracts from bark.

Therapeutic Potential of Flavonoids and Tannins in Management of Oral Infectious Diseases-A Review

Medicinal plants are rich sources of valuable molecules with various profitable biological effects, including antimicrobial activity. The advantages of herbal products are their effectiveness, relative safety based on research or extended traditional use, and accessibility without prescription. Extensive and irrational usage of antibiotics since their discovery in 1928 has led to the increasing expiration of their effectiveness due to antibacterial resistance. Now, medical research is facing a big and challenging mission to find effective and safe antimicrobial therapies to replace inactive drugs. Over the years, one of the research fields that remained the most available is the area of natural products: medicinal plants and their metabolites, which could serve as active substances to fight against microbes or be considered as models in drug design. This review presents selected flavonoids (such as apigenin, quercetin, kaempferol, kurarinone, and morin) and tannins (including oligomeric proanthocyanidins, gallotannins, ellagitannins, catechins, and epigallocatechin gallate), but also medicinal plants rich in these compounds as potential therapeutic agents in oral infectious diseases based on traditional usages such as Agrimonia eupatoria L., Hamamelis virginiana L., Matricaria chamomilla L., Vaccinium myrtillus L., Quercus robur L., Rosa gallica L., Rubus idaeus L., or Potentilla erecta (L.). Some of the presented compounds and extracts are already successfully used to maintain oral health, as the main or additive ingredient of toothpastes or mouthwashes. Others are promising for further research or future applications.

Current Knowledge on Interactions of Plant Materials Traditionally Used in Skin Diseases in Poland and Ukraine with Human Skin Microbiota

Skin disorders of different etiology, such as dermatitis, atopic dermatitis, eczema, psoriasis, wounds, burns, and others, are widely spread in the population. In severe cases, they require the topical application of drugs, such as antibiotics, steroids, and calcineurin inhibitors. With milder symptoms, which do not require acute pharmacological interventions, medications, dietary supplements, and cosmetic products of plant material origin are gaining greater popularity among professionals and patients. They are applied in various pharmaceutical forms, such as raw infusions, tinctures, creams, and ointments. Although plant-based formulations have been used by humankind since ancient times, it is often unclear what the mechanisms of the observed beneficial effects are. Recent advances in the contribution of the skin microbiota in maintaining skin homeostasis can shed new light on understanding the activity of topically applied plant-based products. Although the influence of various plants on skin-related ailments are well documented in vivo and in vitro, little is known about the interaction with the network of the skin microbial ecosystem. The review aims to summarize the hitherto scientific data on plant-based topical preparations used in Poland and Ukraine and indicate future directions of the studies respecting recent developments in understanding the etiology of skin diseases. The current knowledge on investigations of interactions of plant materials/extracts with skin microbiome was reviewed for the first time.

Prenylated Flavonoids in Topical Infections and Wound Healing

The review presents prenylated flavonoids as potential therapeutic agents for the treatment of topical skin infections and wounds, as they can restore the balance in the wound microenvironment. A thorough two-stage search of scientific papers published between 2000 and 2022 was conducted, with independent assessment of results by two reviewers. The main criteria were an MIC (minimum inhibitory concentration) of up to 32 µg/mL, a microdilution/macrodilution broth method according to CLSI (Clinical and Laboratory Standards Institute) or EUCAST (European Committee on Antimicrobial Susceptibility Testing), pathogens responsible for skin infections, and additional antioxidant, anti-inflammatory, and low cytotoxic effects. A total of 127 structurally diverse flavonoids showed promising antimicrobial activity against pathogens affecting wound healing, predominantly Staphylococcus aureus strains, but only artocarpin, diplacone, isobavachalcone, licochalcone A, sophoraflavanone G, and xanthohumol showed multiple activity, including antimicrobial, antioxidant, and anti-inflammatory along with low cytotoxicity important for wound healing. Although prenylated flavonoids appear to be promising in wound therapy of humans, and also animals, their activity was measured only in vitro and in vivo. Future studies are, therefore, needed to establish rational dosing according to MIC and MBC (minimum bactericidal concentration) values, test potential toxicity to human cells, measure healing kinetics, and consider formulation in smart drug release systems and/or delivery technologies to increase their bioavailability.

Optimization of Subcritical Fluid Extraction for Total Saponins from Hedera nepalensis Leaves Using Response Surface Methodology and Evaluation of Its Potential Antimicrobial Activity

(1) Background: Hedera nepalensis (Araliaceae) is a recognized medicinal plant founded in Asia that has been reported to work in antioxidant, antifungal, antimicrobial, and antitumor capacities. (2) Methods: The subcritical fluid extraction of saponin from Hedera nepalensis leaves and the optimum of the extraction process based on yield of saponin contents (by calculating the hederacoside C contents in dried Hedera nepalensis leaves) are examined by response surface methodology (RSM). Furthermore, the antimicrobial activity of the extract is tested for potential drug applications in the future. (3) Results: Based upon RSM data, the following parameters are optimal: extraction time of 3 min, extraction temperature of 150 °C, and a sample/solvent ratio of 1:55 g/mL. Under such circumstances, the achieved yield of saponin is 1.879%. Moreover, the extracts inhibit the growth of some bacterial strains (Streptococcus pneumoniae, Streptococcus pyogenes, Haemophilus influenza) at a moderate to strong level with inhibition zone diameter values ranging from 12.63 to 19.50 mm. (4) Conclusions: The development of such a model provides a robust experimental process for optimizing the extraction factors of saponin contents from Hedera nepalensis extract using subcritical fluid extraction and RSM. Moreover, the current work reveals that saponin extracts of Hedera nepalensis leaves exhibit a potential antimicrobial activity, which can be used as scientific evidence for further study.

Electrospun Polyvinyl Alcohol Loaded with Phytotherapeutic Agents for Wound Healing Applications

In this paper, hydroalcoholic solutions of Thymus vulgaris, Salvia officinalis folium, and Hyperici herba were used in combination with poly (vinyl alcohol) with the aim of developing novel poly (vinyl alcohol)-based nanofiber mats loaded with phytotherapeutic agents via the electrospinning technique. The chemical structure and morphology of the polymeric nanofibers were investigated using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The addition of Thymus vulgaris, Salvia officinalis folium, and Hyperici herba extracts to the pure polyvinyl alcohol fibers led to changes in the morphology of the fibers and a reduction in the fibers’ diameter, from 0.1798 µm in the case of pure polyvinyl alcohol to 0.1672, 0.1425, and 0.1369 µm in the case of polyvinyl alcohol loaded with Thymus vulgaris, Salvia officinalis folium, and Hyperici herba, respectively. The adapted Folin–Ciocalteu (FC) method, which was used to determine the total phenolic contents, revealed that the samples of PVA–Hyperici herba and PVA–Thymus vulgaris had the highest phenol contents, at 13.25 μgGAE/mL and 12.66 μgGAE/mL, respectively. Dynamic water vapor measurements were used in order to investigate the moisture sorption and desorption behavior of the developed electrospun materials. The antimicrobial behavior of these products was also evaluated. Disk diffusion assay studies with Escherichia coli, Staphylococcus aureus, and Methicillin-resistant Staphylococcus aureus were conducted on the developed nanofibers in order to quantify their phytotherapeutic potential.