Antioxidant, Cytotoxic, and Antimicrobial Activities of Glycyrrhiza glabra L., Paeonia lactiflora Pall., and Eriobotrya japonica (Thunb.) Lindl. Extracts

The State-of-the-Art Antibacterial Activities of Glycyrrhizin: A Comprehensive Review

Licorice (Glycyrrhiza glabra) is a plant of the genus Glycyrrhiza in the family Fabaceae/Leguminosae and is a renowned natural herb with a long history of medicinal use dating back to ancient times. Glycyrrhizin (GLY), the main active component of licorice, serves as a widely utilized therapeutic agent in clinical practice. GLY exhibits diverse medicinal properties, including anti-inflammatory, antibacterial, antiviral, antitumor, immunomodulatory, intestinal environment maintenance, and liver protection effects. However, current research primarily emphasizes GLY's antiviral activity, while providing limited insight into its antibacterial properties. GLY demonstrates a broad spectrum of antibacterial activity via inhibiting the growth of bacteria by targeting bacterial enzymes, impacting cell membrane formation, and altering membrane permeability. Moreover, GLY can also bolster host immunity by activating pertinent immune pathways, thereby enhancing pathogen clearance. This paper reviews GLY's inhibitory mechanisms against various pathogenic bacteria-induced pathological changes, its role as a high-mobility group box 1 inhibitor in immune regulation, and its efficacy in combating diseases caused by pathogenic bacteria. Furthermore, combining GLY with other antibiotics reduces the minimum inhibitory concentration, potentially aiding in the clinical development of combination therapies against drug-resistant bacteria. Sources of information were searched using PubMed, Web of Science, Science Direct, and GreenMedical for the keywords "licorice", "Glycyrrhizin", "antibacterial", "anti-inflammatory", "HMGB1", and combinations thereof, mainly from articles published from 1979 to 2024, with no language restrictions. Screening was carried out by one author and supplemented by others. Papers with experimental flaws in their experimental design and papers that did not meet expectations (antifungal papers, etc.) were excluded.

A novel source of biologically active compounds - The leaves of Serbian herbaceous peonies

In order to gain further insight into how various extraction techniques (maceration, microwave-, and ultrasound-assisted extractions) affect the chemical profile and biological activities of leaf extracts from Paeonia tenuifolia L., Paeonia peregrina Mill., and Paeonia officinalis L., this research was performed. The targeted chemical characterization of the extracts was achieved using the Ultra-High-Performance-Liquid-Chromatography-Linear-Trap-Mass-Spectrometry OrbiTrap instrumental technique, while Fourier Transform Infrared Spectroscopy was conducted to investigate the structural properties of the examined leaf extracts. According to the results, the species P. officinalis, Božurna locality as the origin of the plant material, and microwave-assisted extraction produced the maximum polyphenol yield, (491.9 ± 2.7 mg gallic acid equivalent (GAE)/mL). The ethanolic extracts exhibited moderate antioxidant activity as evaluated by DPPH (2,2-diphenyl-1-picrylhydrazyl) and phosphomolybdenum tests. With MIC values of 0.125 mg/mL, the leaf extracts produced by ultrasound-assisted extraction and maceration (Deliblato sands and Bogovo gumno) had the best antibacterial activity against Pseudomonas aeruginosa and Salmonella Typhimurium. Ultrasound-assisted extraction has proven to produce the most effective antimicrobial agents. Inhibitory potential towards glucosidase, amylase, cholinesterases, and tyrosinase was evaluated in enzyme inhibition assays and molecular docking simulations. Results show that leaves of P. tenuifolia L. obtained by ultrasound-assisted extraction had the highest acetylcholinesterase and butyrylcholinesterase inhibitory activity. Namely, the complexity of the polyphenol structures, the extraction method, the used locality, and the different mechanisms of the reactions between bioactives from leaf extracts and other components (free radicals, microorganisms, and enzymes) are the main factors that influence the results of the antioxidant tests, as well as the antibacterial and enzyme-inhibitory activities of the extracts. Hydroxymethyl-phenyl pentosyl-hexoside and acetyl-hydroxyphenyl-hexoside were the first time identified in the leaf extract of the Paeonia species. Due to their proven biological activities and the confirmed existence of bioactive compounds, leaf extracts may find use in foodstuffs, functional foods, and pharmaceutical products.

The Profile and Content of Polyphenolic Compounds and Antioxidant and Anti-Glycation Properties of Root Extracts of Selected Medicinal Herbs

The objective of our study was to analyse the extracts from six medicinal herb roots (marshmallow, dandelion, liquorice, angelica, burdock, and comfrey) in terms of antioxidant capacity (ABTS, DPPH) and inhibition of advanced glycation end product (AGEs) formation. The quantification of phenolic acids and flavonoids was analysed using the UHPLC-DAD-MS method. Fifteen polyphenolic compounds were detected in the studied herbs. The higher number of polyphenols were found in marshmallows (ten polyphenols), while the lowest was in comfrey (five compounds). Liquorice root revealed the highest individual phenolic concentration (382 µg/g dm) with the higher contribution of kaempferol-3-O-rutinoside. Comfrey root extract was characterised by the most abundant TPC (Total Phenolic Content) value (29.79 mg GAE/ g dm). Burdock and comfrey showed the strongest anti-AGE activity studies with the BDA-GLU model. Burdock root was also characterised by the highest anti-AGE activity in the BSA-MGO model. The highest antioxidant capacity was determined by ABTS (72.12 µmol TE/g dw) and DPPH (143.01 µmol TE/g dw) assays for comfrey extract. The p-coumaric acid content was significantly correlated with anti-AGE activity determined by the BSA-MGO model. This research sheds new light on the bioactivity of root herbs, explaining the role of p-coumaric acid in preventing diabetes.

Polyphenol-rich extract from loquat fruit peel prevents hyperlipidemia and hepato-nephrotoxicity in mice: in vivo study and in silico prediction of possible mechanisms involving identified polyphenols and/or their circulating metabolites

Hyperlipidemia is the most well-known cause of metabolic complications and tissue toxicity such as liver steatosis, atherosclerosis and obesity. This study aims to evaluate the preventive effect of loquat fruit peel extract (PE) against tyloxapol-induced hyperlipidemia and related tissue lipotoxicity in mice. The in vivo study was conducted on mice injected daily with tyloxapol at 100 mg per kg B.W. and treated simultaneously with the PE at concentrations of 100 and 200 mg kg-1 or fenofibrate for 28 days. Plasma and tissue lipid biochemical analyses were undertaken using enzymatic methods. The antioxidative stress was revealed by measuring the malondialdehyde content and activities of superoxide dismutase and catalase as well as the scavenging activity against lipoperoxyl radicals. The PE significantly prevented oxidative stress and restored lipid metabolism, plasma glucose, body weight, organ relative mass and biomarkers of hepato-nephrotoxicity as well as the histological structure of the liver and kidneys. It contains five major polyphenols, namely, ferulic acid, caffeic acid, neochlorogenic acid, chlorogenic acid and quercetin. According to molecular docking analysis, these compounds and their circulating metabolites could interact with major proteins implicated in lipid metabolism and oxidative stress. Overall, the study suggests that PE could prevent hyperlipidemia and related toxic tissue complications.

Thyme essential oil fostering the efficacy of aqueous extract of licorice against fungal phytopathogens of Capsicum annuum L

Capsicum annuum L. production is impeded by various biotic factors, including fungal diseases caused by Colletotrichum capsici, Pythium aphanidermatum, and Fusarium oxysporum. Various plant extracts and essential oils are increasingly used to control different plant diseases. In this study, licorice (Glycyrrhiza glabra) cold water extract (LAE) and thyme (Thymus vulgaris) essential oil (TO) were found to be highly effective against the C. annuum pathogens. LAE at 200 mg ml^-1 demonstrated the maximum antifungal activity of 89.9% against P. aphanidermatum, whereas TO at 0.25 mg ml^-1 showed 100% inhibition of C. capsici. However, when used in combination, much lower doses of these plant protectants (100 mg ml^-1 LAE and 0.125 mg ml^-1 TO) exhibited a synergistic effect in controlling the fungal pathogens. Metabolite profiling using gas chromatography-mass spectrometry and high resolution-liquid chromatography-mass spectrophotometry analysis showed the presence of several bioactive compounds. Enhanced cellular components leakage revealed damage to the fungal cell wall and membrane due to and LAE treatment, which can be attributed to the TO lipophilicity and triterpenoid saponins of LAE. TO and LAE treatments also caused a reduction in ergosterol biosynthesis might be due to the presence of thymol and sterol components in the botanicals. Although the aqueous extracts have a low preparation cost, their uses are limited by modest shelf life and lacklustre antifungal effect. We have shown that these limitations can be bypassed by combining oil (TO) with the aqueous extract (LAE). This study further opens the avenues for utilizing these botanicals against other fungal phytopathogens.

Beeswax Alcohol and Fermented Black Rice Bran Synergistically Ameliorated Hepatic Injury and Dyslipidemia to Exert Antioxidant and Anti-Inflammatory Activity in Ethanol-Supplemented Zebrafish

Alcohol abuse, a global health problem, is closely associated with many pathological processes, such as dyslipidemia and cardiovascular disease. In particular, excessive alcohol consumption promotes dyslipidemia and liver damage, such as hepatic steatosis, fibrosis, and cirrhosis. Beeswax alcohol (BWA) is a natural product used for its antioxidant properties that has not been evaluated for its efficacy in alcohol-induced liver injury. In the present study, zebrafish were exposed to 1% ethanol with supplementation of 10% fermented black rice bran (BRB-F), 10% BWA, or 10% mixtures of BWA+BRB-F (MIX). The BRB-F, BWA, and MIX supplementation increased the survival rate dramatically without affecting the body weight changes. In histology of hepatic tissue, alcoholic foamy degeneration was ameliorated by the BWA or MIX supplements. Moreover, dihydroethidium (DHE) and immunohistochemistry staining suggested that the MIX supplement decreased the hepatic ROS production and interleukin-6 expression significantly owing to the enhanced antioxidant properties, such as paraoxonase. Furthermore, the MIX supplement improved alcohol-induced dyslipidemia and oxidative stress. The BWA and MIX groups showed lower blood total cholesterol (TC) and triglyceride (TG) levels with higher high-density lipoprotein-cholesterol (HDL-C) than the alcohol-alone group. The MIX group showed the highest HDL-C/TC ratio and HDL-C/TG ratio with the lowest low-density lipoprotein (LDL)-C/HDL-C ratio. In conclusion, BWA and BRB-F showed efficacy to treat alcohol-related metabolic disorders, but the MIX supplement was more effective in ameliorating the liver damage and dyslipidemia, which agrees with an enhanced antioxidant and anti-inflammatory activity exhibited by BWA/BRB-F in a synergistic manner.

Metabolite profiling and nephroprotective potential of Glycyrrhiza glabra L. roots against cisplatin-induced nephrotoxicity in vitro and in vivo

OBJECTIVES

The present study was conducted to investigate the phytochemical analysis and demonstrate the nephroprotective potential of root extract of Glycyrrhiza glabra L. against cisplatin (CP) -induced nephrotoxicity in vitro and in vivo.

MATERIALS AND METHODS

The HPTLC analysis and UPLC-MS were carried out for standardizing and metabolite profiling of methanolic extract of roots of G. glabra (GGE). Further, in vitro studies were conducted in human embryonic kidney (HEK)-293 cells to evaluate the cytotoxicity and anti-oxidant potential of GGE with CP as a toxicant and ascorbic acid as standard. Also, in vivo nephroprotective potential at doses of 31.5, 63, and 126 mg/kg/day on CP (6 mg/kg, bw, IP) induced nephrotoxicity was evaluated on rodents.

RESULTS

Phytochemical analysis by HPTLC and UPLC-MS revealed the presence of glycyrrhizin, glabridin, and liquiritin along with other bioactive constituents. The in vitro assay of GGE showed significant (P<0.001 nephroprotective, cellular anti-oxidant potential and improvement in morphological changes induced by CP. Further, administration of CP caused significant (P<0.001) elevation in biochemical, inflammatory, oxidative stress, caspase-3, as well as histopathological changes in kidney tissue. Pre-treatment with GGE attenuated the elevated biochemical markers significantly, improved histopathological damage, and showed a comparable result to ascorbic acid and α-ketoanalogue.

CONCLUSION

Present study concluded the nephroprotective potential of GGE which supports the traditional claim of G. glabra roots in various kidney and its related disorders. The nephroprotective activity may be attributed to its anti-oxidant, anti-inflammatory, and anti-apoptosis effects. Thus, it holds promising potential in management of nephrotoxicity.

Simultaneous separation of glycyrrhizic acid, baicalein and wogonin from Radix Glycyrrhizae and Radix Scutellariae using foam fractionation and in vitro activity evaluation

BACKGROUND

In this study, the optimal conditions for the extraction and purification of glycyrrhizic acid from Radix Glycyrrhizae (RG) and baicalein and wogonin from Radix Scutellariae (RS) by foam fractionation were studied on the basis of central composite design (CCD) and response surface methodology.

RESULTS

The results showed that herbal proportion (RG:RS), gas flow and ethanol concentration were the main factors guiding the foam fractionation of RG and RS. The optimum technological parameters were obtained as follows: herbal proportion (RG:RS), 1.86:1.14; gas flow, 109 mL min^-1 ; and ethanol concentration, 53%. Under the optimal operating conditions, the maximal extraction yields of baicalein, glycyrrhizic acid and wogonin were 56.67, 13.25 and 9.51 mg g^-1 , respectively, which were 2.32-, 1.22- and 1.84-fold higher than those of ultrasonic extraction and 17.28-, 1.15- and 9.91-fold higher than those of ultrasonic extraction without hydrolysis, respectively. Investigations on the antioxidant activity showed that the foam-fractionated extract exhibited better free radical scavenging activity (IC₅₀ 13.80 μg mL^-1 ) than that of the ultrasonic extract (IC₅₀ 223.00 μg mL^-1 ). Antibacterial activity showed that the minimum inhibitory concentrations of the foam fractionated extract against Staphylococcus aureus, Candida albicans, Group A Streptococcus and Pseudomonas aeruginosa were 1.38, 1.38, 0.69 and 5.50 mg mL^-1 , respectively.

CONCLUSION

The results indicate that the foam fractionated extract exhibited better extraction yields and free radical scavenging activity than did the ultrasonic extract. Therefore, this fast and eco-friendly method was established and could be a basis for the extraction and separation of other active constituents from herbal medicines. © 2022 Society of Chemical Industry.

GC-MS Analysis of Bioactive Compounds in Methanolic Extracts of Papaver decaisnei and Determination of Its Antioxidants and Anticancer Activities

The Papaver L. plant (Papaver decaisnei) has ethnobotanical records in many countries including Iraqi Kurdistan. The current study investigates the methanol (99.9%) extracts (10 μg/mL) of roots, leaves, and flowers of Papaver decaisnei in terms of phytochemistry by gas chromatography-mass spectrophotometry GC-MS, in vitro antioxidant activity by radical scavenging and reducing power assays, and finally, the anticancer actions as IC50 (inhibitory concentration at 50%) against human colorectal adenocarcinoma (Caco-2), mammary cancer cells (MCF-7), and human cervical carcinoma (HeLa) cells. The results showed 22, 19, and 17 chemicals for roots, leaves, and flowers of P. decaisnei, respectively. The prevalent organic compounds of P. decaisnei were alkaloids (62.03%), phenolics (55.43%), fatty acids (42.51%), esters (32.08%), terpenoids (25.59%), and phytosterols (15.68%), namely, roemerine (70.44%), 9,12,15-octadecatrien-1-ol (37.45%), hexadecanoic acid (33.72%), decarbomethoxytabersonine (24.49%), and γ-sitosterol (11.22%). The antioxidant activity of plant organs was within 39.1–143.5 μg/mL for DPPH, 135.4–276.4 μg/mL for ABTS, 12.4–34.3 μg/mL for FRAP, and 42.6–75.8 μg/mL for CUPRAC assays. The anticancer of P. decaisnei was found as 125.3–388.4 μg/mL against all tested cell lines (Caco-2, MCF-7, and HeLa). The detected alkaloids and bioactivity of P. decaisnei encourage future isolation of those remarkable alkaloids (reomerine) for potential usage in the pharmaceutical industry.

Multifaced Role of Dual Herbal Principles Loaded-Lipid Nanocarriers in Providing High Therapeutic Efficacity

Although many phytochemicals have been used in traditional medicine, there is a great need to refresh the health benefits and adjust the shortcomings of herbal medicine. In this research, two herbal principles (Diosgenin and Glycyrrhiza glabra extract) coopted in the Nanostructured Lipid Carriers have been developed for improving the most desirable properties of herbal medicine—antioxidant and anti-inflammatory actions. The contribution of phytochemicals, vegetable oils and of lipid matrices has been highlighted by comparative study of size, stability, entrapment efficiency, morphological characteristics, and thermal behavior. According to the in vitro MTS and RTCA results, the dual herbal-NLCs were no cytotoxic toward endothelial cells at concentrations between 25 and 100 µg/mL. A rapid release of Glycyrrhiza glabra and a motivated delay of Diosgenin was detected by the in vitro release experiments. Dual herbal-NLCs showed an elevated ability to annihilate long-life cationic radicals (ABTS^•+) and short-life oxygenated radicals (an inhibition of 63.4% ABTS^•+, while the ability to capture radical oxygen species reached 96%). The production of pro-inflammatory cytokines was significantly inhibited by the newly herbals-NLC (up to 97.9% inhibition of TNF-α and 62.5% for IL-6). The study may open a new pharmacotherapy horizon; it provides a comprehensive basis for the use of herbal-NLC in the treatment of inflammatory diseases.

The potential of glycyrrhizin and licorice extract in combating COVID-19 and associated conditions

BACKGROUND

Several recent studies have stated that glycyrrhizin and licorice extract are present in most traditional Chinese medicine formulas used against SARS-CoV-2 in China. Significant data are showing that glycyrrhizin and licorice extract have multiple beneficial activities in combating most features of SARS-CoV-2.

PURPOSE

The aim of current review was to highlight recent progresses in research that showed the evidence of the potential use of glycyrrhizin and licorice extract against COVID-19.

METHODOLOGY

We have reviewed the information published from 1979 to October 2020. These studies demonstrated the effects , use and safety of glycyrrhizin and icorice extract against viral infections,bacterial infections, inflammatory disorders of lung ( in vitro and in vivo).  These studies were collated through online electronic databases research (Academic libraries as PubMed, Scopus, Web of Science and Egyptian Knowledge Bank).

RESULTS

Pooled effect size of articles provides information about the rationale for using glycyrrhizin and licorice extract to treat COVID-19. Fifty studies demonstrate antiviral activity of glycyrrhizin and licorice extract. The most frequent mechanism of the antiviral activity is due to disrupting viral uptake into the host cells and disrupting the interaction between receptor- binding domain (RBD) of SARS-COV2 and ACE2 in recent articles. Fifty studies indicate that glycyrrhizin and licorice extract have significant antioxidant, anti-inflammatory and immunomodulatory effects. Twenty five studies provide evidence for the protective effect of glycyrrhizin and licorice extract against inflammation-induced acute lung injury and cardiovascular disorders.

CONCLUSION

The current study showed several evidence regarding the beneficial effects of glycyrrhizin and licorice extract in combating COVID-19. More randomized clinical trials are needed to obtain a precise conclusion.

Efficacy of Complex Phytoadaptogens as an Adjunct to Non-surgical Treatment of Chronic Periodontitis: A Randomized Clinical Trial

Background:

Many herbal formulas are used in dentistry in the complex treatment and prevention of periodontitis, but it is not always possible to achieve a long-term remission and stimulate regeneration of periodontal structures.

Aim:

The aim of this randomized clinical trial was to assess the efficacy of chronotherapy with complex phytoadaptogens (CFA) as an adjunct to non-surgical periodontal treatment (NSPT) and to achieve long-term remission.

Materials and Methods:

Forty systemically healthy patients with chronic generalized periodontitis (probing pocket depth ≥5 mm) were randomly divided into two groups: patients in one group received treatment with NSPT alone (group 2), whereas patients in another group received CFA in addition to NSPT (group 3). Twenty individuals with healthy periodontium (group 1) composed a control group. The clinical outcomes, Simplified Oral Hygiene Index (OHI-S), Sulcus Bleeding Index (SBI), Periodontal Index (PI), and Doppler ultrasound results, were assessed on baseline, after treatment, and 6 months after treatment.

Results:

There was a statistically significant difference between groups 2 and 3, in favor of group 3 in terms of microcirculation parameters—S (P = 0.03), M (P = 0.02), D (P = 0.03), and RI (P = 0.005); indicators of PI (P = 0.005), SBI (P = 0.03), and OHI-S (P = 0.006) were closer to the normal values during 6-month follow-up. Also there was a statistical difference (P < 0.05) at all time points compared with controls, for several parameters in intragroup comparison.

Conclusion:

The data obtained confirm the hypothesis that CFA application in chronic periodontitis treatment is more than appropriate for long-term prevention due to their immunomodulatory, anti-inflammatory, antioxidant, stress-limiting, chronotropic effects.

4-O-galloylalbiflorin inhibits the activity of CYP3A, 2C9, and 2D in human liver microsomes

The effect of 4-O-galloylalbiflorin on the activity of cytochrome P450 enzymes (CYP450s) is an important factor that may induce drug-drug interaction.The effect of 4-O-galloylalbiflorin on the activity of CYP450s was evaluated in the presence of 0, 2.5, 5, 10, 25, 50, and 100 μM 4-O-galloylalbiflorin in pooled human liver microsomes. The inhibition model and corresponding parameters were assessed b fitting with Lineweaver-Burk plots. The time-dependent study was performed with the incubation time of 0, 5, 10, 15, and 30 min.4-O-galloylalbiflorin significantly inhibited the activity of CYP3A, 2C9, and 2 D in a concentration-dependent manner with the IC50 values of 8.2, 13, and 11 μM, respectively. The inhibition of CYP3A was found to be non-competitive and time-dependent with the Ki value of 4.0 μM and the KI/Kinact value of 2.2/0.030 (μM·min). The inhibition of CYP2C9 and 2 D was not affected by the incubation time but was found to be competitive with the Ki values of 6.7 and 6.6 μM, respectively.The inhibitory effect of 4-O-galloylalbiflorin on the activity of CYP3A, 2C9, and 2 D implying the potential drug-drug interaction between 4-O-galloylalbiflorin and the drugs metabolized by these CYP450s.

Inhibitory Effects of Gyeji-Tang on MMP-9 Activity and the Expression of Adhesion Molecules in IL-4- and TNF-α-Stimulated BEAS-2B Cells

Gyeji-tang (GJT), a traditional herbal formula composed of five herbal medicines, is commonly used to treat the common cold, exogenous febrile disease, fever and headaches in Korea, China and Japan. Although various pharmacological activities of GJT have been reported in several studies, the effect of GJT water extract (GJTWE) on airway inflammation has not yet been investigated. This study aimed to evaluate the effects of GJTWE on airway inflammation-related factors using human bronchial epithelial BEAS-2B cells, and to identify the phytochemicals in GJTWE by ultra-performance liquid chromatography-diode array detector-tandem mass spectrometry (UPLC-DAD-MS/MS) analysis. GJTWE significantly decreased the production of chemokines, including eotaxin-3, eotaxin-1, regulated on activation normal T-cell expressed and secreted (RANTES), and matrix metalloproteinase-9, and the expression of the adhesion molecules, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1, in interleukin-4 + tumor necrosis factor-α (IT)-stimulated BEAS-2B cells. In the UPLC-DAD-MS/MS analysis, 21 phytochemicals, including six flavonoids, two chalcones, five terpenoids, six phenolics, one phenylpropanoid and one coumarin, were identified in GJTWE. The findings suggested that GJTWE might exhibit anti-inflammatory effects on airway inflammation by regulating the expression of inflammatory response-related factors in IT-stimulated BEAS-2B cells; further studies are required to determine the bioactive compounds involved in the inhibition of airway inflammation.

Transdermal Delivery Systems of Natural Products Applied to Skin Therapy and Care

Natural products are favored because of their non-toxicity, low irritants, and market reacceptance. We collected examples, according to ancient wisdom, of natural products to be applied in transdermal delivery. A transdermal delivery system, including different types of agents, such as ointments, patches, and gels, has long been used for skin concerns. In recent years, many novel transdermal applications, such as nanoemulsions, liposomes, lipid nanoparticles, and microneedles, have been reported. Nanosized drug delivery systems are widely applied in natural product deliveries. Nanosized materials notably enhance bioavailability and solubility, and are reported to improve the transdermal permeation of many substances compared with conventional topical formulations. Natural products have been made into nanosized biomaterials in order to enhance the penetration effect. Before introducing the novel transdermal applications of natural products, we present traditional methods within this article. The descriptions of novel transdermal applications are classified into three parts: liposomes, emulsions, and lipid nanoparticles. Each section describes cases that are related to promising natural product transdermal use. Finally, we summarize the outcomes of various studies on novel transdermal agents applied to skin treatments.

Efficacy and Mechanism of Traditional Medicinal Plants and Bioactive Compounds against Clinically Important Pathogens

Traditional medicinal plants have been cultivated to treat various human illnesses and avert numerous infectious diseases. They display an extensive range of beneficial pharmacological and health effects for humans. These plants generally synthesize a diverse range of bioactive compounds which have been established to be potent antimicrobial agents against a wide range of pathogenic organisms. Various research studies have demonstrated the antimicrobial activity of traditional plants scientifically or experimentally measured with reports on pathogenic microorganisms resistant to antimicrobials. The antimicrobial activity of medicinal plants or their bioactive compounds arising from several functional activities may be capable of inhibiting virulence factors as well as targeting microbial cells. Some bioactive compounds derived from traditional plants manifest the ability to reverse antibiotic resistance and improve synergetic action with current antibiotic agents. Therefore, the advancement of bioactive-based pharmacological agents can be an auspicious method for treating antibiotic-resistant infections. This review considers the functional and molecular roles of medicinal plants and their bioactive compounds, focusing typically on their antimicrobial activities against clinically important pathogens.

Herbal Tea for the Management of Pharyngitis: Inhibition of Streptococcus pyogenes Growth and Biofilm Formation by Herbal Infusions

Herbal teas are becoming popular as functional beverages due to their various health promotional properties. This study aimed at assessing 13 hot water infusions (HWIs) from different herbs against streptococcal pharyngitis (strep throat). Licorice root exhibited the lowest minimum inhibitory concentrations (MIC) of 1.56 mg/mL, followed by barberry root, thyme, and oregano flowering shoots, with a MIC of 3.13 mg/mL. At their respective minimum bactericidal concentrations (MBC), licorice showed the bactericidal effect on S. pyogenes within 12 h after exposure while others need 24 h for a similar outcome. The HWIs exhibited inhibitory activity on biofilm formation, ranging from 1.56 to 6.25 mg/mL, which confirmed by ruptured cells or clusters of dead cell debris observed in scanning electron microscope (SEM). Overall, non-toxic concentrations of efficacious HWIs from licorice root, barberry root, thyme, and oregano flowering shoots may provide potential sources for developing herbal teas or biomedicine for the management of S. pyogenes infections.

The complete chloroplast genome of Paeonia lactiflora Pall. (Paeoniaceae)

The complete chloroplast genome sequence of Paeonia lactiflora was obtained by de novo assembly using next-generation sequencing. The circular molecule of the genome constituted of four parts, with 152,731 bp in the complete chloroplast genome, including a large single-copy (LSC) region of 84,402 bp, a small single-copy (SSC) region of 16,969 bp, and two inverted repeat (IRa and IRb) regions of 25,680 bp each. The genome annotation predicted a total of 111 genes, including 77 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic analysis showed the close taxonomical relationship to P. veitchii.

Biological Potential and Medical Use of Secondary Metabolites

This Medicines special issue focuses on the great potential of secondary metabolites for therapeutic applications. The special issue contains 16 articles reporting relevant experimental results and overviews of bioactive secondary metabolites. Their biological effects and new methodologies that improve the lead compounds’ synthesis were also discussed. We would like to thank all 83 authors, from all over the world, for their valuable contributions to this special issue.

Evidence for Anti-Inflammatory Activity of Isoliquiritigenin, 18β Glycyrrhetinic Acid, Ursolic Acid, and the Traditional Chinese Medicine Plants Glycyrrhiza glabra and Eriobotrya japonica, at the Molecular Level

Background: We investigated the effect of root extracts from the traditional Chinese medicine (TCM) plants Glycyrrhiza glabra L., Paeonia lactiflora Pall., and the leaf extract of Eriobotrya japonica (Thunb.) Lindl., and their six major secondary metabolites, glycyrrhizic acid, 18β glycyrrhetinic acid, liquiritigenin, isoliquiritigenin, paeoniflorin, and ursolic acid, on lipopolysaccharide (LPS)-induced NF-κB expression and NF-κB-regulated pro-inflammatory factors in murine macrophage RAW 264.7 cells. Methods: The cytotoxicity of the substances was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. RAW 264.7 cells were treated with LPS (1 μg/mL) or LPS plus single substances; the gene expression levels of NF-κB subunits (RelA, RelB, c-Rel, NF-κB1, and NF-κB2), and of ICAM-1, TNF-α, iNOS, and COX-2 were measured employing real-time PCR; nitric oxide (NO) production by the cells was quantified with the Griess assay; nuclear translocation of NF-κB was visualized by immunofluorescence microscopy with NF-κB (p65) staining. Results: All the substances showed moderate cytotoxicity against RAW 264.7 cells except paeoniflorin with an IC₅₀ above 1000 μM. Glycyrrhiza glabra extract and Eriobotrya japonica extract, as well as 18β glycyrrhetinic acid and isoliquiritigenin at low concentrations, inhibited NO production in a dose-dependent manner. LPS upregulated gene expressions of NF-κB subunits and of ICAM-1, TNF-α, iNOS, and COX-2 within 8 h, which could be decreased by 18β glycyrrhetinic acid, isoliquiritigenin and ursolic acid similarly to the anti-inflammatory drug dexamethasone. NF-κB translocation from cytoplasm to nucleus was observed after LPS stimulation for 2 h and was attenuated by extracts of Glycyrrhiza glabra and Eriobotrya japonica, as well as by 18β glycyrrhetinic acid, isoliquiritigenin, and ursolic acid. Conclusions: 18β glycyrrhetinic acid, isoliquiritigenin, and ursolic acid inhibited the gene expressions of ICAM-1, TNF-α, COX-2, and iNOS, partly through inhibiting NF-κB expression and attenuating NF-κB nuclear translocation. These substances showed anti-inflammatory activity. Further studies are needed to elucidate the exact mechanisms and to assess their usefulness in therapy.