Validation of a 16th Century Traditional Chinese Medicine Use of Ginkgo biloba as a Topical Antimicrobial

The Pharmacology and Toxicology of Ginkgolic Acids: Secondary Metabolites from Ginkgo biloba

Ginkgolic acids (GAs) are distinctive secondary metabolites of Ginkgo biloba (G. biloba) primarily found in its leaves and seeds, with the highest concentration located in the exotesta. GAs are classified as long-chain phenolic compounds, and exhibit structural similarities to lignoceric acid. Their structural diversity arises from variations in the length of side chains and their number of double bonds, resulting in six distinct forms within G. biloba extracts (GBE). Of these, GA (C15:1) is the most prevalent. As inhibitors of SUMOylation, GAs demonstrate significant antitumor activity, and can exert antineoplastic effects through multiple pathways, which positions them as potentially promising therapeutic agents for cancer treatment. Additionally, GAs exhibit notable anti-inflammatory, antibacterial, and antiviral properties, highlighting their multifaceted medicinal potential. Although the pharmacological properties of GAs have been extensively investigated, the associated risks of liver and kidney damage must not be overlooked. GAs can induce significant hepatic damage by promoting cellular apoptosis, oxidative stress, and the disruption of various metabolic processes. Furthermore, a limited number of studies have indicated that GAs may exhibit nephrotoxicity, as well as adverse effects on the skin and nervous system. Due to their recognized toxicity, the concentration of GAs is typically regulated to within 5[Formula: see text]ppm in the standardized G. biloba leaf extract EGb 761. Currently, there is no definitive evidence supporting the mutagenic toxicity of GAs. This review primarily synthesizes recent advancements in understanding the pharmacological and toxicological effects of GAs, along with their underlying mechanisms. It is anticipated that this review will stimulate scholarly discourse and elicit valuable insights.

Microalgal Phenolics: Systematic Review with a Focus on Methodological Assessment and Meta-Analysis

A critical review and analysis of the literature relevant to the phenolic content of eucaryotic microalgae was performed. Several issues were identified and discussed. In summary, the main problems with the reporting on the phenolic content of microalgae are the following: (1) despite its usefulness in the determination of phenolic content in plant samples, the Folin-Ciocalteu assay is non-suitable for microalgal research due to the high presence of interfering compounds in microalgal extracts such as chlorophyll and its derivatives in organic extracts and free aromatic amino acids or nucleotides in aqueous extracts; (2) while there is chromatographic evidence for the presence of simple phenolic acids in most microalgal clades, the lack of critical enzymes of phenolic biosynthesis in most microalgae, as well as the high variability of phenolic profiles even in the same genus, require more extensive research before conclusions are drawn; (3) the accumulation and metabolism of external phenolics by microalgae has been almost universally neglected in studies focusing on the phenolic content of microalgae, even when natural seawater or complex organic media are used in the cultivation process. Despite these issues, the literature focusing on the bioremediation of waste streams rich in phenolics through microalgae demonstrates the ability of those organisms to adsorb, internalize, and in many cases oxidize or transform a wide range of phenolic compounds, even at very high concentrations. Simple phenolics found in waste streams, such as olive mill waste, have been shown to enhance the antioxidant activity and various bioactivities of microalgal extracts, while complex biotransformation products of phenolics have also been characterized. In conclusion, the de novo biosynthesis of phenolic compounds via eucaryotic microalgae requires further investigation with better designed experiments and suitable analytical methods, while the response of microalgae to phenolic compounds in their growth medium is of great practical interest, both in terms of waste treatment and for the production of functional foods, cosmetics, and pharmaceuticals.

Nanostructures for Delivery of Flavonoids with Antibacterial Potential against Klebsiella pneumoniae

Flavonoids are secondary metabolites that exhibit remarkable biological activities, including antimicrobial properties against Klebsiella pneumoniae, a pathogen responsible for several serious nosocomial infections. However, oral administration of these compounds faces considerable challenges, such as low bioavailability and chemical instability. Thus, the encapsulation of flavonoids in nanosystems emerges as a promising strategy to mitigate these limitations, offering protection against degradation; greater solubility; and, in some cases, controlled and targeted release. Different types of nanocarriers, such as polymeric nanoparticles, liposomes, and polymeric micelles, among others, have shown potential to increase the antimicrobial efficacy of flavonoids by reducing the therapeutic dose required and minimizing side effects. In addition, advances in nanotechnology enable co-encapsulation with other therapeutic agents and the development of systems responsive to more specific stimuli, optimizing treatment. In this context, the present article provides an updated review of the literature on flavonoids and the main nanocarriers used for delivering flavonoids with antibacterial properties against Klebsiella pneumoniae.

Inhibitory effect of bilobalide on Staphylococcus aureus von Willebrand factor-binding protein and its therapeutic effect in mice with pneumonia

AIMS

Disabling bacterial virulence with small molecules has been proposed as a potential strategy to prevent bacterial pathogenicity. The von Willebrand factor-binding protein of Staphylococcus aureus was identified previously as a key virulence determinant. Our objective was to discover a von Willebrand-factor binding protein (vWbp) inhibitor distinct from the antibiotics used to prevent infections resulting from S. aureus.

METHODS AND RESULTS

Using coagulation assays, we found that the sesquiterpene trilactone bilobalide blocks coagulation mediated by vWbp, but has no impact on the growth of S. aureus at a concentration of 128 μg ml-1. Moreover, a mouse model of pneumonia caused by S. aureus indicated that bilobalide could attenuate S. aureus virulence in vivo. This effect is achieved not by interfering with the expression of vWbp but by binding to vWbp, as demonstrated by western blotting, thermal shift assays, and fluorescence quenching assays. Using molecular dynamic simulations and point mutagenesis analysis, we identified that the Q17A and R453A residues are key residues for the binding of bilobalide to vWbp.

CONCLUSIONS

Overall, we tested the ability of bilobalide to inhibit S. aureus infections by targeting vWbp and explored the potential mechanism of this activity.

Enhancing Health Benefits through Chlorophylls and Chlorophyll-Rich Agro-Food: A Comprehensive Review

Chlorophylls play a crucial role in photosynthesis and are abundantly found in green fruits and vegetables that form an integral part of our diet. Although limited, existing studies suggest that these photosynthetic pigments and their derivatives possess therapeutic properties. These bioactive molecules exhibit a wide range of beneficial effects, including antioxidant, antimutagenic, antigenotoxic, anti-cancer, and anti-obesogenic activities. However, it is unfortunate that leafy materials and fruit peels often go to waste in the food supply chain, contributing to the prevailing issue of food waste in modern societies. Nevertheless, these overlooked materials contain valuable bioactive compounds, including chlorophylls, which offer significant health benefits. Consequently, exploring the potential of these discarded resources, such as utilizing them as functional food ingredients, aligns with the principles of a circular economy and presents exciting opportunities for exploitation.

Treatment of multidrug-resistant Klebsiella pneumoniae pneumonia in rats with the Wen Run Fei Ning formula: A preliminary study

BACKGROUND & OBJECTIVES

To determine the effect of Wen Run Fei Ning formula (WRFNF) intervention in class I integron-mediated carbapenem-resistant Klebsiella pneumoniae.

METHODS

A drug-susceptibility test and PCR amplification were used to screen for carbapenem-resistant K. pneumoniae containing class I integrons. Following nasal drip and tail vein injection to infect healthy male rats with carbapenem-resistant K. pneumoniae, three models were created: control (group A); model (group B, tail vein injection); and model-WRFNF treatment group (group C, by tail vein injection). Rats in Group C were gavaged with pre-warmed WRFNF extract. On the third, fifth, and seventh days after the experiment, the rats in groups A and B were gavaged with an equal quantity of saline and killed in batches.

RESULTS

Group C showed considerably higher serum IL-6 and TNF- levels on days 3, 5, and 7 compared to group A, as well as a significant increase in peripheral blood leukocyte count and a histopathologic inflammatory cell infiltration of the lungs. As the WRFNF delivery duration was prolonged, group C's histopathologic inflammatory cell infiltration gradually improved in contrast to group B, with the biggest improvement occurring on day 7. Compared to group B, group C's serum IL-6 and TNF- levels were lower. When the trial's duration was increased to 7 days, the levels of IL-6 and TNF- in group C decreased on day 7 compared to on day 5.

INTERPRETATION & CONCLUSION

WRFNF decreased inflammatory cell infiltration as well as IL-6 and TNF expression in the lung of the rats infected with carbapenem-resistant K. pneumoniae.

Ginkgo biloba extracts (GBE) protect human RPE cells from t-BHP-induced oxidative stress and necrosis by activating the Nrf2-mediated antioxidant defence

OBJECTIVES

Age-related macular degeneration (AMD) is a prevalent ocular disease. Dry AMD accounts for most cases of blindness associated with AMD but there are no treatments. Oxidative stress-induced damage to retinal pigment epithelial (RPE) cells is a major contributor to the pathogenesis of dry AMD. This study investigated the protective actions of Ginkgo biloba extracts (GBE) in human RPE cells subjected to tert-butyl hydroperoxide (t-BHP)-mediated oxidative stress.

METHODS

The human ARPE-19 cells were pre-treated with or without GBE before the exposure to t-BHP. Cell viability, cell death profile and lipid peroxidation were assessed. The findings were verified using human primary RPE cultures.

KEY FINDINGS

GBE pre-treatment prevented the increase in lipid peroxidation and necrosis/ferroptosis, and the concurrent viability decrease in RPE cells exposed to t-BHP. It enabled the pronounced activation of Nrf2 and its downstream genes. We found that ERK1/2 phosphorylation was increased to a similar extent by t-BHP and GBE.

CONCLUSION

This study revealed that GBE pre-treatment attenuates pro-oxidant stress and protects human RPE cells from oxidative injury by modulating ERK1/2-Nrf2 axis. These findings suggest that GBE has the potential to be developed as a agent that may be valuable in decreasing AMD progression.

Botanical inhibitors of SARS-CoV-2 viral entry: a phylogenetic perspective

Throughout the SARS-CoV-2 pandemic, the use of botanical dietary supplements in the United States has increased, yet their safety and efficacy against COVID-19 remains underexplored. The Quave Natural Product Library is a phylogenetically diverse collection of botanical and fungal natural product extracts including popular supplement ingredients. Evaluation of 1867 extracts and 18 compounds for virus spike protein binding to host cell ACE2 receptors in a SARS-CoV-2 pseudotyped virus system identified 310 extracts derived from 188 species across 76 families (3 fungi, 73 plants) that exhibited ≥ 50% viral entry inhibition activity at 20 µg/mL. Extracts exhibiting mammalian cytotoxicity > 15% and those containing cardiotoxic cardiac glycosides were eliminated. Three extracts were selected for further testing against four pseudotyped variants and infectious SARS-CoV-2 and were then further chemically characterized, revealing the potent (EC50 < 5 µg/mL) antiviral activity of Solidago altissima L. (Asteraceae) flowers and Pteridium aquilinum (L.) Kuhn (Dennstaedtiaceae) rhizomes.

TiO2-Nanowired Delivery of Chinese Extract of Ginkgo biloba EGb-761 and Bilobalide BN-52021 Enhanced Neuroprotective Effects of Cerebrolysin Following Spinal Cord Injury at Cold Environment

Military personnel during combat or peacekeeping operations are exposed to extreme climates of hot or cold environments for longer durations. Spinal cord injury is quite common in military personnel following central nervous system (CNS) trauma indicating a possibility of altered pathophysiological responses at different ambient temperatures. Our previous studies show that the pathophysiology of brain injury is exacerbated in animals acclimated to cold (5 °C) or hot (30 °C) environments. In these diverse ambient temperature zones, trauma exacerbated oxidative stress generation inducing greater blood-brain barrier (BBB) permeability and cell damage. Extracts of Ginkgo biloba EGb-761 and BN-52021 treatment reduces brain pathology following heat stress. This effect is further improved following TiO₂ nanowired delivery in heat stress in animal models. Several studies indicate the role of EGb-761 in attenuating spinal cord induced neuronal damages and improved functional deficit. This is quite likely that these effects are further improved following nanowired delivery of EGb-761 and BN-52021 with cerebrolysin-a balanced composition of several neurotrophic factors and peptide fragments in spinal cord trauma. In this review, TiO₂ nanowired delivery of EGb-761 and BN-52021 with nanowired cerebrolysin is examined in a rat model of spinal cord injury at cold environment. Our results show that spinal cord injury aggravates cord pathology in cold-acclimated rats and nanowired delivery of EGb-761 and BN-52021 with cerebrolysin significantly induced superior neuroprotection, not reported earlier.

Pharmacological Activities of Ginkgolic Acids in Relation to Autophagy

Plant-derived natural compounds are widely used as alternative medicine in healthcare throughout the world. Ginkgolic acids, the phenolic compounds isolated from the leaves and seeds of Ginkgo biloba, are among the chemicals that have been explored the most. Ginkgolic acids exhibit cytotoxic activity against a vast number of human cancers in various preclinical models in vitro and in vivo. Additionally, the pharmacological activities of ginkgolic acids are also involved in antidiabetic, anti-bacteria, anti-virus, anti-fibrosis, and reno/neuroprotection. Autophagy as a highly conserved self-cleaning process that plays a crucial role in maintaining cellular and tissue homeostasis and has been proven to serve as a protective mechanism in the pathogenesis of many diseases, including neurodegenerative diseases, cancer, and infectious diseases. In this review, we surveyed the pharmacological activities of the major three forms of ginkgolic acids (C13:0, C15:1, and C17:1) that are linked to autophagic activity and the mechanisms to which these compounds may participate. A growing body of studies in last decade suggests that ginkgolic acids may represent promising chemical compounds in future drug development and an alternative remedy in humans.

Discovery of unreported ginkgolides of anti-PAF activity using characteristic ion and neutral loss recognition strategy in Ginkgo biloba L

Ginkgolides are the most important bioactive components of Ginkgo biloba L, of which ginkgolide B has been successfully developed and marketed as a drug. The reported ginkgolides are very rare and exhibit a complex matrix due to the chemodiversity of Ginkgo biloba L. Herein, the global profile of characteristic ion and neutral loss recognition strategy were used for to discover eight undescribed ginkgolides, very rare cyclohexane ginkgolides R-V, ginkgolides D-F, and eight known ginkgolides. These ginkgolides were target isolated and identified using high-resolution mass spectrometry, nuclear magnetic resonance spectroscopy, and X-ray crystallography. The undescribed and known ginkgolides exhibited antiplatelet aggregation activities. In particular, compounds U and D had IC₅₀ values of 2.20 ± 0.15 and 6.50 ± 0.87 μM, respectively. This study has enriched the known structural diversity of ginkgolides and extended the application of mass spectrometry to the global profiling of natural products present in Ginkgo biloba L. Moreover, it could help chemists rapidly discover unreported compounds from a complex matrix.

Therapeutic Versus Preventative Use of Ginkgo biloba Extract (EGb 761) against Indomethacin-Induced Gastric Ulcer in Mice

The main bioactive constituents in the standardized Ginkgo biloba leaf extract (EGb 761) are the terpene lactones and flavonoid glycosides. EGb 761’s antioxidant and anti-inflammatory properties have previously been demonstrated. Indomethacin-induced gastric ulcers have a multifactorial etiology and represent a major restriction to its therapeutic utility. The underlying ulcerogenic process involves oxidative and inflammatory biomolecular insults. This study was performed to explore the curative and preventative benefits of EGb 761 in experimentally-induced ulcers. To develop gastric ulcers in mice, indomethacin (40 mg/kg) was administered orally. EGb 761 (200 mg/kg) was given by gavage for 7 days before (preventative) and after (therapeutic) indomethacin administration. The histological alterations and macroscopic mucosal lesions were assessed. In gastric tissue homogenates, malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO), and inflammatory cytokines were measured. The expressions of cyclooxygenase-2 (COX-2), cytokines, and proliferating cell nuclear antigen (PCNA) in the stomach mucosa were also investigated. The ulcer index, histological alterations, gastric oxidants, and inflammatory biomarkers were all significantly increased by indomethacin. In stomach specimens, it increased COX-2 and PCNA expression. EGb 761 treatments, both prophylactic and therapeutic, resulted in significant reductions in ulcer lesions, nitrosative and oxidative damage, and inflammatory markers, along with the lowering of COX-2 and PCNA expressions. Furthermore, in the fight against stomach ulcers, EGb 761 treatment was found to be more efficient than prevention.

Preparation of ZIF-8 and Its Application in Determination of Pyridoxine and Pyridoxal in Ginkgo Seeds by Ultra-Performance Liquid Chromatography

A new rapid and accurate method was developed for simultaneous determination of pyridoxine and pyridoxal in ginkgo seeds, using ultra-performance liquid chromatography (UPLC) equipped with a fluorescence detector. Diluted hydrochloric acid solution was used as the extracting solvent. For the pretreatment of extracts, a zeolitic imidazolate framework material (ZIF-8) was prepared and characterized. An ODS-BP column (4.6 mm × 250 mm × 5 μm) was used for separation. The conditions of sample extraction, cleaning and separation were optimized. The linear correlation coefficient (R²) of the analyte was better than 0.9999, indicating good linearity. The limits of detection (LODs) of pyridoxal and pyridoxine were 0.0065 mg/kg and 0.0057 mg/kg, respectively, and limits of quantitation (LOQs) were 0.022 mg/kg and 0.019 mg/kg, respectively. The recovery of the two substances ranged from 86.2% to 110.4%, and the relative standard deviation (n = 6) was less than 7.5%. The method was applied to determine the contents of pyridoxine and pyridoxal in actual ginkgo seed samples with satisfactory results.

Anti-Depressant Properties of Crocin Molecules in Saffron

Saffron is a valued herb, obtained from the stigmas of the C. sativus Linn (Iridaceae), with therapeutic effects. It has been described in pharmacopoeias to be variously acting, including as an anti-depressant, anti-carcinogen, and stimulant agent. The therapeutic effects of saffron are harbored in its bioactive molecules, notably crocins, the subject of this paper. Crocins have been demonstrated to act as a monoamine oxidase type A and B inhibitor. Furthermore, saffron petal extracts have experimentally been shown to impact contractile response in electrical field stimulation. Other research suggests that saffron also inhibits the reuptake of monoamines, exhibits N-methyl-d-aspartate antagonism, and improves brain-derived neurotrophic factor signaling. A host of experimental studies found saffron/crocin to be similarly effective as fluoxetine and imipramine in the treatment of depression disorders. Saffron and crocins propose a natural solution to combat depressive disorders. However, some hurdles, such as stability and delivery, need to be overcome.

The Mechanism of Action of Ginkgolic Acid (15:1) against Gram-Positive Bacteria Involves Cross Talk with Iron Homeostasis

With the increasing reports of community-acquired and nosocomial infection caused by multidrug-resistant Gram-positive pathogens, there is an urgent need to develop new antimicrobial agents with novel antibacterial mechanisms. Here, we investigated the antibacterial activity of the natural product ginkgolic acid (GA) (15:1), derived from Ginkgo biloba, and its potential mode of action against the Gram-positive bacteria Enterococcus faecalis and Staphylococcus aureus. The MIC values of GA (15:1) against clinical E. faecalis and S. aureus isolates from China were ≤4 and ≤8 μg/mL, respectively, from our test results. Moreover, GA (15:1) displayed high efficiency in biofilm formation inhibition and bactericidal activity against E. faecalis and S. aureus. During its inhibition of the planktonic bacteria, the antibacterial activity of GA (15:1) was significantly improved under the condition of abolishing iron homeostasis. When iron homeostasis was abolished, inhibition of planktonic bacteria by GA (15:1) was significantly improved. This phenomenon can be interpreted as showing that iron homeostasis disruption facilitated the disruption of the functions of ribosome and protein synthesis by GA (15:1), resulting in inhibition of bacterial growth and cell death. Genetic mutation of ferric uptake regulator (Fur) led to GA (15:1) tolerance in in vitro-induced resistant derivatives, while overexpression of Fur led to increased GA (15:1) susceptibility. Additionally, GA (15:1) significantly decreased the bacterial loads of S. aureus strain USA300 in the lung tissues of mice in a pneumonic murine model. Conclusively, this study revealed an antimicrobial mechanism of GA (15:1) involving cross talk with iron homeostasis against Gram-positive pathogens. In the future, the natural product GA (15:1) might be applied to combat infections caused by Gram-positive pathogens.

IMPORTANCE The increasing emergence of infectious diseases associated with multidrug-resistant Gram-positive pathogens has raised the urgent need to develop novel antibiotics. GA (15:1) is a natural product derived from Ginkgo biloba and possesses a wide range of bioactivities, including antimicrobial activity. However, its antibacterial mechanisms remain unclear. Our current study found that the function of ferric uptake regulator (Fur) was highly correlated with the antimicrobial activity of GA (15:1) against E. faecalis and that the antibacterial activity of GA (15:1) could be strengthened by the disruption of iron homeostasis. This study provided important insight into the mode of action of GA (15:1) against Gram-positive bacteria and suggested that GA (15:1) holds the potential to be an antimicrobial treatment option for infection caused by multidrug-resistant Gram-positive pathogens.

Systemic and topical Ginkgo biloba leaf extract (Egb-761) ameliorated rat paw inflammation in comparison to dexamethasone

ETHNOPHARMACOLOGICAL RELEVANCE

Ginkgo Biloba leaf extract (Egb-761) is used for treating various inflammatory disease conditions therefore this study was performed.

AIM OF THE STUDY

The present study aimed at comparing the ameliorative effects of both systemic and topical Egb-761 versus dexamethasone on carrageenan-induced hind paw inflammation in rats.

MATERIAL AND METHODS

Wistar albino rats were injected with carrageenan solution in the sub-planter region of the right hind paw. Egb-761 and dexamethasone were administered systemically to two groups while Egb-761 ointment 2% and dexamethasone sodium phosphate ointment were applied topically for another two groups. Vernier Caliper was used to assess rat paw thickness. Tissue malondialdehyde (MDA), nitric oxide (NO), and tumor necrosis factor-α (TNF-α) levels have been estimated.

RESULTS

Carrageenan induced a significant rat paw edema and inflammation noticed 1 h post-injection as well as an increase of MDA, NO, and TNF-α in the inflamed skin tissues compared to the control group. Systemic and topical administration of Egb-761 and dexamethasone resulted in a significant reduction in carrageenan-induced rat paw edema. They reduced the tissue levels of MDA, NO, and TNF-α. Dexamethasone showed a little bit superior anti-inflammatory and antioxidant efficacy over Egb-761.

CONCLUSION

Our findings indicate the possibility of the therapeutic value of Egb-761 for alleviation of local inflammation by attenuating the increased MDA, NO and TNF-α levels.

Is Our Natural Food Our Homeostasis? Array of a Thousand Effect-Directed Profiles of 68 Herbs and Spices

The beneficial effects of plant-rich diets and traditional medicines are increasingly recognized in the treatment of civilization diseases due to the abundance and diversity of bioactive substances therein. However, the important active portion of natural food or plant-based medicine is presently not under control. Hence, a paradigm shift from quality control based on marker compounds to effect-directed profiling is postulated. We investigated 68 powdered plant extracts (botanicals) which are added to food products in food industry. Among them are many plants that are used as traditional medicines, herbs and spices. A generic strategy was developed to evaluate the bioactivity profile of each botanical as completely as possible and to straightforwardly assign the most potent bioactive compounds. It is an 8-dimensional hyphenation of normal-phase high-performance thin-layer chromatography with multi-imaging by ultraviolet, visible and fluorescence light detection as well as effect-directed assay and heart-cut of the bioactive zone to orthogonal reversed-phase high-performance liquid chromato-graphy-photodiode array detection-heated electrospray ionization mass spectrometry. In the non-target, effect-directed screening via 16 different on-surface assays, we tentatively assigned more than 60 important bioactive compounds in the studied botanicals. These were antibacterials, estrogens, antiestrogens, androgens, and antiandrogens, as well as acetylcholinesterase, butyrylcholinesterase, α-amylase, α-glucosidase, β-glucosidase, β-glucuronidase, and tyrosinase inhibitors, which were on-surface heart-cut eluted from the bioautogram or enzyme inhibition autogram to the next dimension for further targeted characterization. This biological-physicochemical hyphenation is able to detect and control active mechanisms of traditional medicines or botanicals as well as the essentials of plant-based food. The array of 1,292 profiles (68 samples × 19 detections) showed the versatile bioactivity potential of natural food. It reveals how efficiently and powerful our natural food contributes to our homeostasis.

Characterization of natural herbal medicines by thin-layer chromatography combined with laser ablation-assisted direct analysis in real-time mass spectrometry

The characterization and quality control of natural herbal medicines, such as traditional Chinese medicines (TCMs), is of great significance to ensure their potential efficacy and avoid severe side effects. Thin-layer chromatography (TLC) is a simple and classic approach for examining quality marker of natural products. Nevertheless, it is more difficult to further characterize the compounds adsorbed on the TLC plate. Herein, we reported a simple setup of laser ablation-assisted direct analysis in real-time mass spectrometry (LA-DART-MS), in which the coupling of mass spectrometry information to provide a predominant dimension in the identification of unknown chemical compositions separated on standard TLC plates, and it was applied for rapid characterization of various kinds of natural herbal medicines. The results showed that the introduction of low-cost small laser pointer had significantly improved the desorption process. The system was successfully applied in the analysis of alkaloids, flavonoids, anthraquinones, volatile oils, glycosides, organic acids, and eight different TCMs including Sophorae Flavescentis Radix, Angelicae Sinensis Radix, Acori Tatarinowii Rhizoma, Phellodendri Chinensis Cortex, Picrasmae Ramulus et Folium, Gynura Japonica, Rhei Radix et Rhizoma and Dendrobii Caulis. The obtained limits of detection (LODs) of this method for various types of reference substances were in the range of 4.6-162.2 ng/band on TLC plates. Furthermore, the quality control and identification of different species of Dendrobii Caulis herb was achieved. This study combines the advantages of TLC and ambient mass spectrometry to provide a good choice for the screening and identification of active ingredients and the quality evaluation of botanical samples.

Ginkgolic Acid Inhibits Coronavirus Strain 229E Infection of Human Epithelial Lung Cells

Since December 2019, the COVID-19 pandemic has affected more than 200 million individuals around the globe and caused millions of deaths. Although there are now multiple vaccines for SARS-CoV-2, their efficacy may be limited by current and future viral mutations. Therefore, effective antiviral compounds are an essential component to win the battle against the family of coronaviruses. Ginkgolic Acid (GA) is a pan-antiviral molecule with proven effective in vitro and in vivo activity. We previously demonstrated that GA inhibits Herpes Simplex Virus 1 (HSV-1) by disrupting viral structure, blocking fusion, and inhibiting viral protein synthesis. Additionally, we reported that GA displays broad-spectrum fusion inhibition encompassing all three classes of fusion proteins, including those of HIV, Ebola, influenza A, and Epstein Barr virus. Here, we report that GA exhibited potent antiviral activity against Human Coronavirus strain 229E (HCoV-229E) infection of human epithelial lung cells (MRC-5). GA significantly reduced progeny virus production, expression of viral proteins, and cytopathic effects (CPE). Furthermore, GA significantly inhibited HCoV-229E even when added post-infection. In light of our findings and the similarities of this family of viruses, GA holds promising potential as an effective antiviral treatment for SARS-CoV-2.

Ginkgo biloba Seeds—An Environmental Pollutant or a Functional Food

Ginkgo biloba has been cultivated in Bulgaria since the end of the 19th century. Ividual specimens can be seen in almost every park. Females of the tree are considered contaminants of the landscape because their ripe seeds have a strong odor and are not utilized. We undertook this study to clarify whether ginkgo seeds of local origin can be converted from an unwanted and unused environmental pollutant into a source of beneficial compounds. Various analytical and chromatographic methods were used to quantify the major constituents and ten biologically active compounds in methanol seed extract. The results showed that the seeds are low in proteins (5%) and fats (1%); the seeds were also rich in unsaturated fatty acids and tocopherols. About 44% of nut starch was resistant to in vitro enzymatic hydrolysis. The amount of terpene trilactones in an aqueous-methanol seed extract was significantly higher than the number of flavonoids. Ginkgotoxin and ginkgolic acid were also found. The extract demonstrated weak antimicrobial activity against thirteen microorganisms. This study revealed that seeds of locally grown Ginkgo trees can be used as a source of biologically active substances. The chemical composition show similarity to those of seeds from other geographical areas.

Medicinal plants from the Himalayan region for potential novel antimicrobial and anti-inflammatory skin treatments

BACKGROUND AND OBJECTIVES

Adequate treatment of wounds remains one of the major medical needs globally, most notably in the regions with poor or limited access to health care. In many local and traditional systems of medicine, plants are often widely used for treating infected wounds.

AIM AND OBJECTIVES

The overarching aim of this project was selection of potential species for use in a future treatment by combining with plant resources with aspects of antimicrobial photodynamic therapy (aPDT). Specifically, we focussed on species used locally in the Himalayan region for the treatment of skin disorders and then assessed the existing pharmacological evidence for key species based on the published evidence available.

METHODS

Database searches were performed to identify relevant publications describing local and traditional uses of plants in the Himalayan region of Bhutan, PR China, India, Nepal and Pakistan. Using the Global Biodiversity Information Facility (GBIF), species were researched in terms of their distribution including in different climatic regions, focussing on species mostly found in higher climatic zones (based on the Köppen-Geiger climate classification). For species used in three or more countries and restricted to the higher altitudes, data on safety, pharmacology, as it relates to dermatological conditions, and phytochemistry were retrieved.

KEY FINDINGS

The study identified a total of 606 species that are used in the treatment of various skin conditions often associated with infections reported in 84 articles. Common weeds like Ageratum conyzoides and Bidens pilosa, widely used and cultivated species like Centealla asiatiaca and Prunus armenica were excluded. This ultimately led to the identification of a core group of five widely used species restricted to the Himalayan region (Cedrus deodara, Nardostachys jatamansi, Pinus wallichiana, Pinus roxburghii and Valeriana jatamansi).

CONCLUSIONS

Here we apply a novel approach comprising an assessment of the published information on the use of medicinal plants (i.e. local and traditional knowledge) in the context of their potential to be used in a biomedical form of clinical treatment - aPDT. Then, once sustainable sourcing based on access and benefit-sharing arrangements is in place, these species are investigated for their potential in wound treatment. Ultimately, the goal is to develop a new baseline for primary health care in some of the regions of the world with poor or limited access to health care.

Procyanidin B2 and rutin in Ginkgo biloba extracts protect human retinal pigment epithelial (RPE) cells from oxidative stress by modulating Nrf2 and Erk1/2 signalling

Oxidative stress plays an important role in the pathogenesis of human retinal diseases. Ginkgo biloba products are widely consumed herbal supplements that contain ingredients with anti-oxidant potentials. However, the active agents in ginkgo biloba extracts (GBE) are unclear. This study assessed the anti-oxidant effects of 19 natural compounds isolated from GBE to provide a rational basis for their use in preventing retinal diseases. The compounds were tested in retinal pigment epithelial (RPE) cells subjected to tert-butyl hydroperoxide (t-BHP)-induced oxidative stress. Cell viability and intracellular reactive oxygen species (ROS) were assessed and flow cytometry was used to delineate the cell death profile. The expression of nuclear factor erythroid 2-related factor-2 (Nrf2) was activated in RPE cells by t-BHP accompanied with an activation of Erk1/2 signaling. GBE-derived rutin and procyanidin B2 ameliorated t-BHP-induced cell death and promoted cell viability by suppressing intracellular ROS generation. These agents also enhanced Nrf2 expression with activating Erk1/2 signaling in RPE cells. In contrast, the other compounds tested were minimally active and did not prevent the loss of cell viability elicited by t-BHP. The present findings suggest that rutin and procyanidin B2 may have potential therapeutic values in the prevention of retinal diseases induced by oxidative damage.

Medicinal plants and natural products as neuroprotective agents in age-related macular degeneration

The retina may suffer neurodegenerative damages, as other tissues of the central nervous system do, and serious eye diseases may develop. One of them is age-related macular degeneration, which causes progressive loss of vision due to retina degeneration. Treatment of age-related macular degeneration focuses on antioxidant agents and anti-vascular endothelial growth factor compounds, among others, that prevent/diminish oxidative stress and reduce neovascularisation respectively. The phytochemicals, medicinal plants and/or plant-diet supplements might be a useful adjunct in prevention or treatment of age-related macular degeneration owing to their antioxidant and anti-vascular endothelial growth factor properties. This review article presents the most investigated plants and natural products in relation to age-related macular degeneration, such as saffron, ginkgo, bilberry and blueberry, curcuma or turmeric, carotenoids, polyphenols, and vitamins C and E. This study provides up-to-date information on the effects, treatments, safety and efficiency of these phytotherapy products.

Cytotoxic effect of Ginkgo biloba kernel extract on HCT116 and A2058 cancer cell lines

While the pharmacology of Ginkgo biloba leaf extract has been studied extensively, little is known about the pharmacological potential of Ginkgo biloba seeds, although they contain similar active ingredients that are responsible for the therapeutic effects of the leaf extract. In this study we used 70%-methanol Ginkgo biloba kernel extract, quantified its bioactive constituents and tested their cytotoxic effect on two cancer cell lines, A2058 and HCT116, and the non-tumor cell line McCoy-Plovdiv. We studied the biological effect of the extract by real-time analysis in the xCELLigence system, WST-1 assay and LIVE/DEAD viability assay. We show that the extract significantly perturbed the viability of cancer cells in a concentration- and time-dependent manner. In contrast, non-cancerous McCoy-Plovdiv cells sustained their proliferation potential even at high concentrations of the extract. Therefore, we propose that the active constituents of the Ginkgo biloba endosperm extract may interact additively or synergistically to protect against cancer.

Full-length sequencing of ginkgo transcriptomes for an in-depth understanding of flavonoid and terpenoid trilactone biosynthesis

Ginkgo biloba L. is regarded as the most ancient living tree, and its kernel has been used as a traditional Chinese medicine for more than 2,000 years. The leaf extracts of this tree have been among the bestselling herbal remedies in Western countries since the last century. To understand the biosynthesis of the pharmacologically active ingredients in G. biloba, flavonoids and terpenoid trilactones (TTLs), we sequenced the transcriptomes of G. biloba leaves, kernels and testae with Iso-Seq and RNA-Seq technologies and obtained 152,524 clean consensus reads. When these reads were used to improve the annotation of the G. biloba genome, 4,856 novel genes, 25,583 new isoforms of previously annotated genes and 4,363 lncRNAs were discovered. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that genes involved in growth, regulation and response to stress were more likely to be regulated by alternative splicing (AS) or alternative polyadenylation (APA), which represent the two most important posttranscriptional regulation mechanisms. It was found that some of the characterized genes involved in the biosynthesis of flavonoids and TTLs were also possibly regulated by AS and APA. Using phylogenetic and gene expression pattern analyses, some candidate genes for the biosynthesis of flavonoids and TTLs were screened. After qRT-PCR validation, the final candidate genes for flavonoid biosynthesis included three UDP-glycosyltransferases and one MYB transcription factor, while the candidate genes for TTL biosynthesis included two cytochrome P450 and one WRKY transcription factor. Our study suggested that Iso-Seq may play an important role in improving genome annotation, elucidating AS and APA mechanisms and discovering candidate genes involved in the biosynthesis of some secondary metabolites.

Natural Compounds from the Marine Brown Alga Caulocystis cephalornithos with Potent In Vitro-Activity against the Parasitic Nematode Haemonchus contortus

Eight secondary metabolites (1 to 8) were isolated from a marine sponge, a marine alga and three terrestrial plants collected in Australia and subsequently chemically characterised. Here, these natural product-derived compounds were screened for in vitro-anthelmintic activity against the larvae and adult stages of Haemonchus contortus (barber's pole worm)-a highly pathogenic parasitic nematode of ruminants. Using an optimised, whole-organism screening system, compounds were tested on exsheathed third-stage larvae (xL3s) and fourth-stage larvae (L4s). Anthelmintic activity was initially evaluated on these stages based on the inhibition of motility, development and/or changes in morphology (phenotype). We identified two compounds, 6-undecylsalicylic acid (3) and 6-tridecylsalicylic acid (4) isolated from the marine brown alga, Caulocystis cephalornithos, with inhibitory effects on xL3 and L4 motility and larval development, and the induction of a "skinny-straight" phenotype. Subsequent testing showed that these two compounds had an acute nematocidal effect (within 1-12 h) on adult males and females of H. contortus. Ultrastructural analysis of adult worms treated with compound 4 revealed significant damage to subcuticular musculature and associated tissues and cellular organelles including mitochondria. In conclusion, the present study has discovered two algal compounds possessing acute anthelmintic effects and with potential for hit-to-lead progression. Future work should focus on undertaking a structure-activity relationship study and on elucidating the mode(s) of action of optimised compounds.

Herbal Medicine of the 21st Century: A Focus on the Chemistry, Pharmacokinetics and Toxicity of Five Widely Advocated Phytotherapies

Widely advocated for their health benefits worldwide, herbal medicines (HMs) have evolved into a billion dollar generating industry. Much is known regarding their wellness inducing properties, prophylactic and therapeutic benefits for the relief of both minor to chronic ailment conditions given their long-standing use among various cultures worldwide. On the other hand, their equally meaningful chemistry, pharmacokinetic profile in humans, interaction and toxicity profile have been poorly researched and documented. Consequently, this review is an attempt to highlight the health benefits, pharmacokinetics, interaction, and toxicity profile of five globally famous HMs. A systematic literature search was conducted by browsing major scientific databases such as Bentham Science, SciFinder, ScienceDirect, PubMed, Google Scholar and EBSCO to include 196 articles. In general, ginsenosides, glycyrrhizin and curcumin demonstrate low bioavailability when orally administered. Ginkgo biloba L. induces both CYP3A4 and CYP2C9 and alters the AUC and Cmax of conventional medications including midazolam, tolbutamide, lopinavir and nifedipine. Ginsenosides Re stimulates CYP2C9, decreasing the anticoagulant activity of warfarin. Camellia sinensis (L.) Kuntze increases the bioavailability of buspirone and is rich in vitamin K thereby inhibiting the activity of anticoagulant agents. Glycyrrhiza glabra L. displaces serum bound cardiovascular drugs such as diltiazem, nifedipine and verapamil. Herbal medicine can directly affect hepatocytes leading to hepatoxicity based on both intrinsic and extrinsic factors. The potentiation of the activity of concurrently administered conventional agents is potentially lethal especially if the drugs bear dangerous side effects and have a low therapeutic window.

Exploring the Anti-Acne Potential of Impepho [Helichrysum odoratissimum (L.) Sweet] to Combat Cutibacterium acnes Virulence

The Gram-positive bacterium Cutibacterium acnes (previously Propionibacterium acnes), plays an important role in the pathogenesis and progression of the dermatological skin disorder acne vulgaris. The methanolic extract of Helichrysum odoratissimum (L.) Sweet (HO-MeOH) was investigated for its ability to target bacterial growth and pathogenic virulence factors associated with acne progression. The gas chromatography-mass spectrometry (GC-MS) analysis of HO-MeOH identified α-humulene (3.94%), α-curcumene (3.74%), and caryophyllene (8.12%) as major constituents, which correlated with previous reports of other Helichrysum species. The HO-MeOH extract exhibited potent antimicrobial activity against C. acnes (ATCC 6919) with a minimum inhibitory concentration (MIC) of 7.81 µg/ml. It enhanced the antimicrobial activity of benzoyl peroxide (BPO). The extract showed high specificity against C. acnes cell aggregation at sub-inhibitory concentrations, preventing biofilm formation. Mature C. acnes biofilms were disrupted at a sub-inhibitory concentration of 3.91 µg/ml. At 100 µg/ml, HO-MeOH reduced interleukin-1α (IL-1α) cytokine levels in C. acnes-induced human keratinocytes (HaCaT) by 11.08%, highlighting its potential as a comedolytic agent for the treatment of comedonal acne. The extract exhibited a 50% inhibitory concentration (IC50) of 157.50 µg/ml against lipase enzyme activity, an enzyme responsible for sebum degradation, ultimately causing inflammation. The extract's anti-inflammatory activity was tested against various targets associated with inflammatory activation by the bacterium. The extract inhibited pro-inflammatory cytokine levels of IL-8 by 48.31% when compared to C. acnes-induced HaCaT cells at 7.81 µg/ml. It exhibited cyclooxygenase-II (COX-II) enzyme inhibition with an IC50 of 22.87 µg/ml. Intracellular nitric oxide (NO) was inhibited by 40.39% at 7.81 µg/ml when compared with NO production in lipopolysaccharide (LPS)-induced RAW264.7 cells. The intracellular NO inhibition was potentially due to the 2.14 fold reduction of inducible nitric oxide synthase (iNOS) gene expression. The HO-MeOH extract exhibited an IC50 of 145.45 µg/ml against virulent hyaluronidase enzyme activity, which is responsible for hyaluronan degradation and scar formation. This study provides scientific validation for the traditional use of H. odoratissimum as an ointment for pimples, not only due to its ability to control C. acnes proliferation but also due to its inhibitory activity on various targets associated with bacterial virulence leading to acne progression.

Transcriptional profiling of long noncoding RNAs associated with leaf-color mutation in Ginkgo biloba L

BACKGROUND

Long noncoding RNAs (lncRNAs) play an important role in diverse biological processes and have been widely studied in recent years. However, the roles of lncRNAs in leaf pigment formation in ginkgo (Ginkgo biloba L.) remain poorly understood.

RESULTS

In this study, lncRNA libraries for mutant yellow-leaf and normal green-leaf ginkgo trees were constructed via high-throughput sequencing. A total of 2044 lncRNAs were obtained with an average length of 702 nt and typically harbored 2 exons. We identified 238 differentially expressed lncRNAs (DELs), 32 DELs and 49 differentially expressed mRNAs (DEGs) that constituted coexpression networks. We also found that 48 cis-acting DELs regulated 72 target genes, and 31 trans-acting DELs regulated 31 different target genes, which provides a new perspective for the regulation of the leaf-color mutation. Due to the crucial regulatory roles of lncRNAs in a wide range of biological processes, we conducted in-depth studies on the DELs and their targets and found that the chloroplast thylakoid membrane subcategory and the photosynthesis pathways (ko00195) were most enriched, suggesting their potential roles in leaf coloration mechanisms. In addition, our correlation analysis indicates that eight DELs and 68 transcription factors (TFs) might be involved in interaction networks.

CONCLUSIONS

This study has enriched the knowledge concerning lncRNAs and provides new insights into the function of lncRNAs in leaf-color mutations, which will benefit future selective breeding of ginkgo.