Four new ginkgolic acids from Ginkgo biloba

Ginkgo biloba extract safety: Insights from a real-world pharmacovigilance study of FDA adverse event reporting system (FAERS) events

ETHNOPHARMACOLOGICAL RELEVANCE

A traditional Chinese medicine extracted from the Ginkgophyta, Ginkgo biloba is commonly used to treat cardiac cerebral disease all over the world. Limited data exist regarding adverse drug reactions associated with Ginkgo biloba extract post-marketing.

AIM OF THE STUDY

Currently, the drug safety profile of Ginkgo biloba extract is assessed using a substantial volume of case safety reports within the FDA Adverse Event Reporting System (FAERS) database.

MATERIALS AND METHODS

The study collected adverse events (AEs) data associated with Ginkgo biloba extract as the primary suspected drug from 2004 to 2023 from the FAERS database. A standardized mapping analysis of System Organ Class (SOC) and preferred term (PT) was conducted. Utilizing reporting odds ratio (ROR), proportional reporting ratio (PRR), information component (IC), and empirical Bayes geometric mean (EBGM), significant disproportionate measurement signals of adverse drug reactions (ADR) were identified and high-intensity signals were analyzed.

RESULTS

700 reports of adverse events related to Ginkgo biloba extract were found in the FAERS database, affecting 23 organ systems. 88 significant mismatches were identified using four algorithms, leading to unexpected major adverse events like amaurosis fugax, fractional exhaled nitric oxide created, and obstructive sleep apnoea syndrome. The study observed a median onset time of AE associated with Ginkgo biloba extract at 7 days (interquartile interval [IQR] 0-109 days), with the majority of AE manifesting within the initial 7 days of drug treatment initiation. This investigation identified a noteworthy AE signal for Ginkgo biloba extract, underscoring the importance of clinical surveillance and risk assessment in its use.

CONCLUSIONS

In clinical practice, this study provides a deeper and broader understanding of suspected adverse reactions associated with Ginkgo biloba extract.

Manganese-arginine nanozymes as oxidase mimics for smartphone-based intelligent detection of 4'-O-methylpyridoxine

By self-assembly of MnCl2 and arginine under alkaline conditions, ultra-small MnArg nanoparticles were successfully constructed as oxidase (OXD) mimics for intelligent detection of the Ginkgo toxin 4'-O-methylpyridoxal (MPN). The obtained MnArg nanozymes possessed excellent OXD-like activity and thermal stability. Based on the inhibitory effect of MPN for the catalytic activity of MnArg, this system was utilized for the colorimetric sensing of MPN with a low limit of detection (LOD) of 2.16 µg mL-1. The detection  system exhibited good selectivity against other potential interferents. FTIR data showed that the presence of MPN binds with MnArg and shields the active sites, thereby interfering with the oxidase-like activity. Combined with a smartphone and the ColorMax software, this nanozyme-based intelligent detection platform could effectively detect MPN with a LOD of 2.1 µg mL-1. Our MnArg nanozyme-based system was applied to detect real ginkgo nut samples with recoveries of 92.4-108.7%, and the relative standard deviations were less than 0.7%. This work may promote the development of novel nanozymes and expand their applications in the field of food safety detection.

Ginkgo biloba L. exocarp petroleum ether extract inhibits methicillin-resistant Staphylococcus aureus by modulating ion transport, virulence, and biofilm formation in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

As reported in the Ancient Chinese Medicinal Books, Ginkgo biloba L. fruit has been used as a traditional Chinese medicine for the treatment asthma and cough or as a disinfectant. Our previous study demonstrated that G. biloba exocarp extract (GBEE), an extract of a traditional Chinese herb, inhibits the formation of methicillin-resistant Staphylococcus aureus (MRSA) biofilms. However, GBEE is a crude extract that contains many components, and the underlying mechanisms of purified GBEE fractions extracted with solvents of different polarities are unknown.

AIM OF THE STUDY

This study aimed to investigate the different components in GBEE fractions extracted with solvents of different polarities and their antibacterial effects and mechanisms against MRSA and Staphylococcus haemolyticus biofilms both in vitro and in vivo.

METHODS

The components in different fractions were detected by high-performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS). Microbroth dilution assays and time growth curves were used to determine the antibacterial effects of the fractions on 15 clinical bacterial isolates. Crystal violet staining, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to identify the fractions that affected bacterial biofilm formation. The potential MRSA targets of the GBEE fraction obtained with petroleum ether (PE), denoted GBEE-PE, were screened by transcriptome sequencing, and the gene expression profile was verified by quantitative polymerase chain reaction (qPCR).

RESULTS

HPLC-HRMS analysis revealed that the four GBEE fractions (extracted with petroleum ether, ethyl acetate, n-butanol, and water) contained different ginkgo components, and the antibacterial effects decreased as the polarity of the extraction solvent increased. The antibacterial activity of GBEE-PE was greater than that of the GBEE fraction extracted with ethyl acetate (EA). GBEE-PE improved H. illucens survival and reduced MRSA colonization in model mouse organs. Crystal violet staining and SEM and TEM analyses revealed that GBEE-PE inhibited MRSA and S. haemolyticus biofilm formation. Transcriptional analysis revealed that GBEE-PE inhibits MRSA biofilms by altering ion transport, cell wall metabolism and virulence-related gene expression. In addition, the LO2 cell viability and H. illucens toxicity assay data showed that GBEE-PE at 20 mg/kg was nontoxic.

CONCLUSION

The GBEE fractions contained different components, and their antibacterial effects decreased with increases in the polarity of the extraction solvent. GBEE-PE limited MRSA growth and biofilm formation by affecting ion transport, cell wall synthesis, and virulence-related pathways. This research provides a more detailed overview of the mechanism by which GBEE-PE inhibits MRSA both in vitro and in vivo and suggests that GBEE-PE is a new prospective antimicrobial with the potential to be used in MRSA therapeutics in the future.

Leaves, seeds and exocarp of Ginkgo biloba L. (Ginkgoaceae): A Comprehensive Review of Traditional Uses, phytochemistry, pharmacology, resource utilization and toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Ginkgo biloba L. (Ginkgoaceae) is a treasure species with high medicinal value. The Ming Dynasty "Compendium of Materia Medica" and Qing Dynasty "Bencao Fengyuan" in China recorded this herbal medicine can reduce phlegm, clear poison, treat diarrhea and frequent urination, etc. AIM OF THE STUDY: Until now, there is no painstakingly summarized review on leaves, seeds and exocarp of G. biloba simultaneously. This review will systematically summarize and compare current knowledge of G. biloba.

MATERIALS AND METHODS

Ample original publications related to traditional uses, phytochemistry, pharmacology, resource utilization and toxicity of G. biloba leaves, seeds and exocarp till the end of 2021 were searched and collected by using various literature databases, including China National Knowledge Infrastructure, PubMed, Elsevier, Springer, Google Scholar and Web of Science database.

RESULTS

According to classical Chinese herbal books and Chinese Pharmacopoeia, relieving cough, reducing phlegm, clearing poison and relieving diarrhea are the main pharmacological effects of G. biloba. The common chemical ingredients in different parts of G. biloba are flavonoids, terpenoids, phenolic acids, polysaccharides and endotoxin, etc. Among them, flavonoids and terpenoids are the main bioactive compounds in G. biloba leaves. Phenolic acids are the main bioactive compounds in G. biloba exocarp. G. biloba seeds are rich in nutritional ingredients, such as starch, adipose, protein, etc. Modern pharmacological studies showed that the crude extracts or compounds of G. biloba leaves, seeds and exocarp can be used for treating cardiovascular and cerebrovascular diseases, Alzheimer's disease, atherosclerosis, cancer, asthma, non-alcoholic fatty liver, diabetic complications and other diseases. In daily life, G. biloba seeds were usually used as raw material or additives for commodities, healthy food, drinks, even insecticides and antibacterial agents, etc. G. biloba leaves and seeds have been mainly applied for treating cardiovascular and cerebrovascular diseases, cough and asthma in clinical. However, endotoxins and ginkgolic acids have been identified as the dominating toxic ingredients in different parts of G. biloba. Besides, flavonoids and ginkgolides also have been proved to have toxicity recently.

CONCLUSIONS

This review systematically sums up and compares the traditional uses, phytochemistry, pharmacology, resource utilization and toxicity research progress of G. biloba leaves, seeds and exocarp for the first time. It will provide some comprehensive reference data and suggestions for future research on this herbal medicine.

Divinylcarbinol Desymmetrization Strategy: A Concise and Reliable Approach to Chiral Hydroxylated Fatty Acid Derivatives

By the aid of the catalytic desymmetrization of divinylcarbinol as one-pot asymmetric induction and protection of olefin, asymmetric total syntheses of two chiral hydroxylated fatty acid derivatives were successfully achieved. The desired stereoisomers could be concisely prepared in mild conditions in a highly convergent manner. Thus, this novel strategy can help stereochemical elucidations of natural products, which have difficulties in spectroscopic stereochemical analyses due to their local symmetries in the vicinities of the stereogenic secondary hydroxyl units.

Application of targeted 2D planar chromatography in the control of ginkgolic acids in some herbal drugs and dietary supplements

Two-step targeted 2D planar chromatographic method (2DTLC) was used in the determination of ginkgolic acids in pharmaceuticals and dietary supplements. The choice of the extraction method and the separation technique was guided by the formulation type (capsule, tablet, tincture) with expected low amounts of ginkgolic acids in the analyzed herbal samples. Separation of ginkgolic acids C15:1 and C17:1 on HPTLC RP18 WF254s was preceded by its separation from the sample matrix on TLC Si60 F254s. Mobile phases consisted of acetonitrile/water/formic acid (80:20:1, V/V/V) and n-heptane/ethyl acetate/formic acid (20:30:1, V/V/V), resp. Identification of separated compounds was based on 2D-TLC co-chromatography with reference substances and off-line 2D-TLC x HPLC-DAD-ESI-MS analysis. Quantification of ginkgolic acids C15:1 and C17:1 was conducted densitometrically. Among the analyzed products, the presence of ginkgolic acids was confirmed only in herbal drugs containing 60 % ethanolic tinctures of Ginkgo biloba leaves. The use of TLC in the quantification of ginkgolic acids C15:1 and C17:1 in ginkgo extracts was described for the first time.

Determination of Total Flavonoids Contents and Antioxidant Activity of Ginkgo biloba Leaf by Near-Infrared Reflectance Method

Background

Total flavonoids content (TFC) is one of the most important quality indexes of Ginkgo biloba leaf, and it is concerned with total antioxidant activity. Near-infrared spectroscopy (NIR) method has showed its advantages in fast, accurate, qualitative, and quantitative analysis of various components in many quality control researches. In this study, a calibration model was built by partial least squares regression (PLSR) coupling with NIR spectrum to quantitatively analyze the TFC and total antioxidant activity of Ginkgo biloba leaf.

Results

During the model establishing, some spectrum pretreatment and outlier diagnosis methods were optimized to establish the final model. The coefficients of determination (R² ) for TFC and total antioxidant activity prediction were 0.8863 and 0.8486, respectively; and the root mean square errors of prediction (RMSEP) were 2.203 mg/g and 0.2211 mM/g, respectively.

Conclusion

These results showed that NIR method combined with chemometrics is suitable for quantitative analysis of main components and their activities and might be applied to quality control of relevant products.