Immobilized α-amylase magnetic beads for ligand fishing: Proof of concept and identification of α-amylase inhibitors in Ginkgo biloba

Diabetes mellitus is a widespread metabolic disorder that affects millions of people around the world. The disease is a major burden on both economic and social levels, and there is a need for improved drugs with fewer side effects in the management of the disease. Current methods for isolation of anti-diabetic lead compounds from complex mixtures suffer from low resolution and sensitivity, and there is a need for improved alternatives. In this work, magnetic ligand fishing combined with high-performance liquid chromatography - photodiode-array detection - high-resolution mass spectrometry - solid-phase extraction - nuclear magnetic resonance spectroscopy (HPLC-PDA-HRMS-SPE-NMR) was developed and validated, with the aim of accelerating discovery of natural products targeting α-amylase. The enzyme was successfully immobilized onto magnetic beads and retained its catalytic activity for a period of 75 days, and the specificity of this method was successfully validated by testing the N-terminus coupled α-amylase immobilized magnetic beads on an artificial mixture. A proof of concept experiment, using a crude ethyl acetate extract of Ginkgo biloba leaves, proved that it was possible to fish out four α-amylase ligands. HPLC-PDA-HRMS-SPE-NMR analysis confirmed the presence of bilobetin, isoginkgetin, ginkgetin and sciadopitysin in the solutions resulting from α-amylase ligand fishing with Ginkgo biloba. IC₅₀ curves revealed a reversed relationship between concentration of sciadopitysin and inhibition of α-amylase activity, suggesting that this compound activated the enzyme instead of inhibiting it.

LIR Motif-Containing Hyperdisulfide β-Ginkgotide is Cytoprotective, Adaptogenic, and Scaffold-Ready

Grafting a bioactive peptide onto a disulfide-rich scaffold is a promising approach to improve its structure and metabolic stability. The ginkgo plant-derived β-ginkgotide β-gB1 is a highly unusual molecule: Small, hyperdisulfide, and found only in selected ancient plants. It also contains a conserved 16-amino-acid core with three interlocking disulfides, as well as a six-amino-acid inter-cysteine loop 2 suitable for grafting peptide epitopes. However, very little is known about this recently-discovered family of molecules. Here, we report the biophysical and functional characterizations of the β-ginkgotide β-gB1 from G. biloba. A circular dichroism spectroscopy analysis at 90 °C and proteolytic treatments of β-gB1 supported that it is hyperstable. Data mining revealed that the β-gB1 loop 2 contains the canonical LC3 interacting region (LIR) motif crucial for selective autophagy. Cell-based assays and pull-down experiments showed that β-gB1 is an adaptogen, able to maintain cellular homeostasis through induced autophagosomes formation and to protect cells by targeting intracellular proteins from stress-mediated damage against hypoxia and the hypoxia-reoxygenation of induced cell death. This is the first report of an LIR-containing peptide natural product. Together, our results suggest that the plant-derived β-ginkgotide is cytoprotective, capable of targeting intracellular proteins, and holds promise as a hyperdisulfide scaffold for engineering peptidyl therapeutics with enhanced structural and metabolic stability.

Efficacy and safety of ginkgo injections in the treatment of angina pectoris caused by coronary heart disease in China: a network Meta-analysis and systematic review

OBJECTIVE

To assess the clinical efficacy and safety of ginkgo injections (GIs) combined with conventional treatment (CT) against angina pectoris (AP) due to coronary heart disease (CHD).

METHODS

Randomized controlled trials (RCTs) that used GIs to treat AP were searched in SinoMed, PubMed, China National Knowledge Infrastructure Database, Chinese Scientific Journals Database, Wanfang Database, Embase and Cochrane Library until March 2017. The Cochrane"risk of bias"method was used to evaluate the methodological quality of RCTs. Data were analyzed using Stata v13.1 and WinBUGS v1.4.3.

RESULTS

A total of 73 RCTs involving 7621 patients were included. A Bayesian network Meta-analysis of RCTs was undertaken, and the advantages of four types of GI-supplemented CT in AP treatment were determined.

CONCLUSION

GI-assisted CT was more effective against AP than CT alone. However, based on the limitations of the study, additional high-quality RCTs are required to confirm our findings.

Simultaneous adsorption and degradation of triclosan by Ginkgo biloba L. stabilized Fe/Co bimetallic nanoparticles

Triclosan (TCS), an antimicrobial agent added in many pharmaceutical and personal care products, can cause some environmental problems due to its bioaccumulation, toxicity and potential antibiotic cross-resistance. In this study, Ginkgo biloba L. leaf extract was used as the green stabilizing agent to synthesize Fe/Co bimetallic nanoparticles (G-Fe/Co NPs), which were applied to remove TCS from aqueous solution. G-Fe/Co NPs were characterized by TEM, EDS, SEM, BET, FTIR, XRD and XPS. G. biloba L. leaf extract improved the dispersion and reduced the passivation of NPs. The TCS removal efficiency followed the order of G-Fe/Co NPs > G-Fe NPs > Co NPs > Fe/Co NPs > Fe NPs. G-Fe/Co NPs can be reused at least eight times. The Co leaching under different initial pH values was negligible. The factors affecting the TCS removal were investigated. The results indicated that the removal of TCS followed pseudo-second-order kinetics, and the removal rate constant decreased with increasing the initial pH value and the initial TCS concentration, and decreasing the Co loading of G-Fe/Co NPs and NPs dosage. The mass balance of TCS removal by G-Fe/Co NPs indicated that adsorption was dominant process and TCS degradation was an accumulative process.

Anticancer Effects of Five Biflavonoids from Ginkgo Biloba L. Male Flowers In Vitro

Ginkgo biloba L., an ancient dioecious gymnosperm, is now cultivated worldwide for landscaping and medical purposes. A novel biflavonoid—amentoflavone 7′′-O-β-d-glucopyranoside (1)—and four known biflavonoids were isolated and identified from the male flowers of Ginkgo. The anti-proliferative activities of five biflavonoids were evaluated on different cancer lines. Bilobetin (3) and isoginkgetin (4) exhibited better anti-proliferative activities on different cancer lines. Their effects were found to be cell-specific and in a dose and time dependent manner for the most sensitive HeLa cells. The significant morphological changes validated their anticancer effects in a dose-dependent manner. They were capable of arresting the G2/M phase of the cell cycle, inducing the apoptosis of HeLa cells dose-dependently and activating the proapoptotic protein Bax and the executor caspase-3. Bilobetin (3) could also inhibit the antiapoptotic protein Bcl-2. These might be the mechanism underlying their anti-proliferation. In short, bilobetin (3) and isoginkgetin (4) might be the early lead compounds for new anticancer agents.

Effect of Ginkgo biloba seed exopleura extract and chitosan coating on the postharvest quality of ginkgo seed

BACKGROUND

The effects of Ginkgo biloba seed exopleura extract (GSEE) and chitosan (CH) coating on the preservation of ginkgo seeds were investigated.

RESULTS

Results showed that CH could alleviate the decay rate, and that CH combined with GSEE (CH-GSEE) treatment further inhibited the development of seed decay due to the additional antifungal activity of GSEE. The nutrient contents, including water, starch and soluble protein, were maintained by both CH-GSEE and CH treatments. CH-GSEE treatment led to better restriction on oxidative stress by decreasing superoxide anion production rate, membrane permeability, malondialdehyde content, respiration rate and ethylene production rate. The antioxidant enzyme activities of peroxidase, superoxide dismutase and catalase in ginkgo seeds were maintained by treatment with CH-GSEE at a higher level. These results were consistent with the enhanced visual appearance, qualities and storability of the CH-GSEE-treated seeds. Principal component analysis provided a global view of the internal relations of the ginkgo seeds with different treatments.

CONCLUSIONS

The postharvest qualities of CH-GSEE-treated seeds were better than those of other treatment groups. Therefore, CH-GSEE is an effective and alternative way for inhibiting decay, maintaining quality and extending the postharvest life of ginkgo seeds. © 2018 Society of Chemical Industry.

Ginkgo biloba sarcotesta polysaccharide inhibits inflammatory responses through suppressing both NF-κB and MAPK signaling pathway

BACKGROUND

Polysaccharides, common components of natural products extensively studied as dietary supplements and functional foods, have been found to have various activities. In the present study, a water-soluble polysaccharide, namely GBSP3a, was isolated and purified from G. biloba sarcotesta. The anti-inflammatory activity of GBSP3a in lipopolysaccharide (LPS)-induced RAW264.7 macrophages and the potential underlying molecular mechanisms were then assessed.

RESULTS

GBSP3a exerted its anti-inflammatory effect by remarkably inhibiting the secretion of pro-inflammatory mediators and cytokines, including nitric oxide (NO), prostaglandin E₂ (PGE₂ ), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) in LPS-stimulated RAW264.7 macrophages. Excessive mRNA and protein expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were dose-dependently inhibited by GBSP3a in LPS-stimulated RAW264.7 cells. Further research suggested that the anti-inflammatory effect of GBSP3a can be attributed to the modulation of the NF-κB and MAPK signaling pathways.

CONCLUSION

GBSP3a exhibits anti-inflammatory activity and exerts its anti-inflammatory effect probably through suppressing both NF-κB and MAPK signaling pathway, indicating that GBSP3a could be used for the development of anti-inflammatory agent or nutraceuticals. © 2018 Society of Chemical Industry.

Metabolomics Integrated with Transcriptomics Reveals Redirection of the Phenylpropanoids Metabolic Flux in Ginkgo biloba

Ginkgo biloba is a monotypic species native to China with great economic and ecological values. Leaves extract of this tree contains about 24% flavonoids, which are widely used in the pharmaceutical industry. However, the flavonoids biosynthesis pathway is poorly understood in Ginkgo. In this study, we comprehensively compared the transcriptome and metabolite profiles of Ginkgo high-flavonoids mutant (ZY1) and Anlu1 (control) leaves. A total of 122 significantly changed metabolites and 1683 differentially expressed genes (DEGs), including 45 transcription factors, were identified in ZY1 compared to those in Anlu1. An integrated analysis of metabolic and transcriptomic data revealed that the abundances of some major flavonoids (especially flavone and flavonol) were most significantly increased, while other phenylpropanoid-derived products and lipids showed the most largely reduced abundances in ZY1 compared to those in Anlu1. Quantitative real-time polymerase chain reaction results confirmed the alterations in the expression levels of genes encoding components of pathways involved in phenylpropanoids and lipids. The redirection of metabolic flux may contribute to increased accumulation of flavonoid levels in ZY1 leaves. Our results provide valuable information for metabolic engineering of Ginkgo flavonoids biosynthesis.

Immunostimulating effects of Ginkgo biloba extract against toxicity induced by organophosphate pesticide, diazinon in rainbow trout, Oncorhynchus mykiss: innate immunity components and immune-related genes

The immunostimulating and therapeutic properties of Ginkgo biloba (GB) have always been the focus of traditional medicine over thousands of years. During last decade, special attentions were paid to use of GB in aquaculture to enhance fish health and survival. In the present study, we investigated for the first time the immunogenic effects of dietary GB against oxidative and toxicity induced by organophosphate pesticide, diazinon. In non-diazinon-exposed fish, the plasma total immunoglobulin, lysozyme activity, and peroxidase activity significantly elevated after 60-day experiment in fish supplemented with 1 and 2 g GB/kg diet (p < 0.05). The respiratory burst activity and complement activity significantly increased only in groups supplemented with 0.5 g GB/kg diet (p < 0.05). Furthermore, the peroxidase activity, total immunoglobulin, and lysozyme activity significantly declined in groups supplemented with 4 g GB/kg diet during feeding trial (p < 0.05). There were no significant differences in expression of interleukin 1 beta (IL-1β) and transforming growth factor beta 1 (TGF-β1) genes in kidney between control group (non-GB-supplemented fish) and GB-supplemented fish (p > 0.05). In diazinon-exposed fish, all immunity components significantly decreased during exposure in control and those fed 0.5 and 4 g GB/kg diet (p < 0.05). In fish fed 1 and 2 g GB/kg diet, no alternations were found in immunity components during exposure period (p > 0.05). In addition, diazinon induced the expression of IL-1β and TGF-β1 genes in control and fish fed 0.5 and 4 g GB/kg diet (p < 0.05). No significant changes were observed in expression of IL-1β and TGF-β1 genes in fish supplemented with 1 and 2 g GB/kg (p > 0.05). In conclusion, the results of the present study suggest an immunogenic role for dietary GB at optimum dietary levels (1-2 g GB/kg diet) against toxicity induced by diazinon. Nevertheless, GB at high dietary levels (4 g GB/kg diet) showed immunosuppressive effects, which makes it necessary to optimize its levels in diet.

Ginkgolide A Prevents the Amyloid-β-Induced Depolarization of Cortical Neurons

Utilizing the N-methyl-d-aspartate (NMDA) receptor antagonist as a strategy, memantine is the only agent available for clinically treating mild to severe Alzheimer's disease (AD). Our aim was to develop novel similar herb-based drugs. Using a screening platform, ginkgolide A (GA), a pure compound extracted from Ginkgo biloba, was found to attenuate amyloid β (Aβ)-induced abnormal depolarization in mouse primary cortical neurons. Using receptor agonists, it was determined that GA inhibits both NMDA receptors and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors. Furthermore, the Aβ-induced increase in c-Jun N-terminal kinase phosphorylation in neurons was prevented by GA. Body weight, glutamate oxaloacetate transaminase, glutamic-pyruvic transaminase, liver histology, and kidney histology were similar when the wild-type/AD animal model mice with and without GA treatment were compared. This pure compound improves the memory of wild-type mice. Our findings indicate that GA has great potential clinically for the treatment of AD because it might target NMDA receptors just like memantine.

Ginkgo biloba induces different gene expression signatures and oncogenic pathways in malignant and non-malignant cells of the liver

Ginkgo biloba (EGb761) is a widely used botanical drug. Several reports indicate that EGb761 confers preventive as well as anti-tumorigenic properties in a variety of tumors, including hepatocellular carcinoma (HCC). We here evaluate functional effects and molecular alterations induced by EGb761 in hepatoma cells and non-malignant hepatocytes. Hepatoma cell lines, primary human HCC cells and immortalized human hepatocytes (IH) were exposed to various concentrations (0–1000 μg/ml) of EGb761. Apoptosis and proliferation were evaluated after 72h of EGb761 exposure. Response to oxidative stress, tumorigenic properties and molecular changes were further investigated. While anti-oxidant effects were detected in all cell lines, EGb761 promoted anti-proliferative and pro-apoptotic effects mainly in hepatoma cells. Consistently, EGb761 treatment caused a significant reduction in colony and sphere forming ability in hepatoma cells and no mentionable changes in IH. Transcriptomic changes involved oxidative stress response as well as key oncogenic pathways resembling Nrf2- and mTOR signaling pathway. Taken together, EGb761 induces differential effects in non-transformed and cancer cells. While treatment confers protective effects in non-malignant cells, EGb761 significantly impairs tumorigenic properties in cancer cells by affecting key oncogenic pathways. Results provide the rational for clinical testing of EGb761 in preventive and therapeutic strategies in human liver diseases.

The Potential Use of Plant Natural Products and Plant Extracts with Antioxidant Properties for the Prevention/Treatment of Neurodegenerative Diseases: In Vitro, In Vivo and Clinical Trials

Neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease and Huntington's disease, present a major health issue and financial burden for health care systems around the world. The impact of these diseases will further increase over the next decades due to increasing life expectancies. No cure is currently available for the treatment of these conditions; only drugs, which merely alleviate the symptoms. Oxidative stress has long been associated with neurodegeneration, whether as a cause or as part of the downstream results caused by other factors. Thus, the use of antioxidants to counter cellular oxidative stress within the nervous system has been suggested as a potential treatment option for neurological disorders. Over the last decade, significant research has focused on the potential use of natural antioxidants to target oxidative stress. However, clinical trial results have lacked success for the treatment of patients with neurological disorders. The knowledge that natural extracts show other positive molecular activities in addition to antioxidant activity, however, has led to further research of natural extracts for their potential use as prevention or treatment/management of neurodegenerative diseases. This review will cover several in vitro and in vivo research studies, as well as clinical trials, and highlight the potential of natural antioxidants.

Metal Contents in the Most Widely Consumed Commercial Preparations of Four Different Medicinal Plants (Aloe, Senna, Ginseng, and Ginkgo) from Europe

Medicinal plants like Aloe barbadensis, Ginkgo biloba, Panax ginseng, and Cassia angustifolia are being increasingly used but self-medication is a major public health challenge because of their numerous interactions. Furthermore, dietary exposure to metals through the consumption of these commercial preparations should be evaluated. Some of these metals may have a nutritional interest but others are metals of toxicological relevance. The content of essential and toxic metals has been analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) in 80 samples of both organically and conventionally grown aloe, senna, ginseng, and ginkgo pharmaceutical formats to establish their metallic profile, to evaluate their nutritional value and to assess the toxic metal risk resulting from their consumption. Ca (9181 mg/kg ww) in senna, Fe (30.0 mg/kg ww) in ginseng, and Al (15.7 mg/kg ww) in ginseng are noteworthy. The consumption of 9 g/day of ginkgo represents 6.44% of the RDI set for Ca. The consumption of 25 mL/day of aloe syrup is 3.06% (men) and 1.52% (women) of the RDI of Fe. Al exposure from 25 mL/day of aloe consumption is 2.71% of its TDI. Considering the dosages recommended by the manufacturers, the intake of toxic metals does not pose a health risk but the intake of essential metals is worth mentioning.

Effect of Ginkgo biloba leaf extract on cerebral cortex amino acid levels in cerebral ischemia model rats

OBJECTIVE

To investigate the effect of Ginkgo biloba leaf extract on amino acid levels in the cerebral cortex of cerebral ischemia model rats induced by middle cerebral artery occlusion (MCAO).

METHODS

A rat model of cerebral ischemia was established by MCAO. Male rats were divided into a negative control group (Control), a sham-operated group (Sham), an ischemic group (MCAO), and an ischemic group treated with Ginkgo biloba leaf extract (MCAO_D). All groups were divided into two subgroups with occlusion times of 12 and 24 h, respectively. The levels of 18 endogenous amino acids in the cerebral cortex were quantified by triple quadrupole-liquid chromatography-mass spectrometry.

RESULTS

Compared with the MCAO group, behavioral performance, neurological deficit score, and cerebral infarct volume were significantly improved in the MCAO_D group (P < 0.05, P < 0.01). Compared with the sham group, the levels of 17 amino acids in the cerebral cortex were markedly changed in the MCAO group. The levels of Alanine (Ala), Isoleucine (Ile), Glutamic acid (Glu), Serine (Ser), Valine (Val), Phenylalanine (Phe), Proline (Pro), Threonine (Thr), Lysine (Lys), Tyrosine (Tyr), Hydroxyproline (Hyp), Arginine (Arg), Leucine (Leu), Tryptophan (Trp), and Glycine (Gly) were increased (P < 0.001, P < 0.05), while levels of Gln and Tau were decreased (P < 0.001, P < 0.05). Compared with the MCAO group, Ginkgo biloba extract treatment in the MCAO_D group significantly down-regulated the levels of 11 amino acids, especially those of Arg, Thr, and Ser in 12 or 24 h.

CONCLUSION

Injection of Ginkgo biloba leaf extract has a therapeutic effect on model rats with MCAO-induced cerebral ischemia by acting on amino acids in the cerebral cortex. This effect might be associated with the regulation of amino acid metabolism in the cerebral cortex.

Effect of heat treatment on 4'-O-methylpyridoxine (MPN) content in Ginkgo biloba seed extract solution

BACKGROUND

A vitamin B₆ derivative, 4'-O-methylpyridoxine (MPN), is responsible for food poisoning by Ginkgo biloba seeds. In this study, we investigate the content of pyridoxine and MPN in MPN standard solution and G. biloba seed extract solution upon heat treatment in order to evaluate the reduction of toxic components in G. biloba seed by such treatment.

RESULTS

Heat treatment was conducted at 90-150 °C for 0-60 min, and all samples were adjusted to the same concentration of 1 g L^-1 . The MPN content decreased to 994.92-563.69 mg kg^-1 for MPN standard solution and to 371.56-76.84 mg kg^-1 for G. biloba seed extract solution, and in both cases decreased even further with increasing heat treatment time. However, in all samples, except for the 90 °C heat treatment group, the pyridoxine content in MPN standard solution increased with increasing heat temperature and time; in addition, the extract solution showed a similar tendency. This may be the result of thermal degradation of MPN into pyridoxine.

CONCLUSION

We can expect to improve the utilization of functional food materials by applying suitable heat treatment conditions and decreasing the MPN content of the G. biloba seed. © 2018 Society of Chemical Industry.

Determination and Comparison of 4'- O-Methylpyridoxine Analogues in Ginkgo biloba Seeds at Different Growth Stages

The antivitamin B₆, 4'- O-methylpyridoxine (MPN); its glucoside, 4'- O-methylpyridoxine-5'-glucoside (MPNG); and vitamin B₆ compounds, including pyridoxal (PL), pyridoxamine, pyridoxine, pyridoxal-5'-phosphate (PLP), and pyridoxamine-5'-phosphate, exist in Ginkgo biloba seeds, which are widely used as food and medicine. This work aimed to determine the MPN analogues in G. biloba seeds at different growth stages in terms of cultivars and ages of trees. The highest total MPN contents of 249.30, 295.62, and 267.85 μg/g were obtained in the mature stages of three selected G. biloba samples. The total contents of vitamin B₆ compounds decreased significantly in the entire growth period of the three samples. Principal-component analysis revealed that MPN and MPNG were important contributors in the MPN-analogue metabolism of G. biloba seeds. The influence of the cultivar on the content and composition of MPN analogues was greater than that of the age of the G. biloba tree.

Chemical analysis, pharmacological activity and process optimization of the proportion of bilobalide and ginkgolides in Ginkgo biloba extract

Variations on the efficacy of commercial Ginkgo biloba preparations have been reported, although all the products follow the same standards. Terpene trilactones (TTLs), including bilobalide (BB) and ginkgolides, are one of the main active components in G. biloba extract and have been received the most attention due to their chemical uniqueness and their importance for quality control. A plenty of studies demonstrated that BB and ginkgolides display differential activities on various biological processes. However, the influence of different ratios of BB and ginkgolides on the efficacy of TTLs has not been detected yet. The aims of this study were: (1) to test whether different ratios of BB and ginkgolides existed in commercial G. biloba preparations; (2) to detect the influence of different ratios of BB and ginkgolides on the in vivo efficacy of TTLs; and (3) to optimize the extraction process of G. biloba to approach the better BB and ginkgolides ratio with the maximum in vivo effects. First, the content and proportion of BB and ginkgolides in various G. biloba preparations were quantified by HPLC-MS analysis. As the results, an obvious fluctuation in the proportion of BB and ginkgolides was observed in the preparations from different commercial suppliers. The ratio was ranged from 0.3 to 0.8. Second, a zebrafish thrombosis model was used to evaluate the antithrombotic effects of different ratios of BB and ginkgolides. The result showed that the proportion of BB and ginkgolides at 1:2 produced the maximum antithrombotic effects. Third, the extraction process of G. biloba was optimized using a design space technique aiming to approach the best BB and ginkgolides ratio obtained from zebrafish experiment. The extraction process was modeled based on the results of Box-Behnken designed experiments. Design space was then calculated using a probability-based method. Within this design space, G. biloba extraction process can be guaranteed to achieve the better BB and ginkgolides ratio with high assurance. Normal operation space for G. biloba extraction process was recommended as ethanol concentration of 50% to 70%, liquid-to-solid ratio of 5.6 mL/g to 7.3 mL/g, and extraction time of 2.2 h to 3.0 h. This work not only suggest that the proportion of BB and ginkgolides should be used as a quality control index in ginkgo preparations besides the content of TTLs, but also provide a way to approach it with the extraction process parameters controlled in the normal operation ranges.

Characterization, Cytotoxicity, and Genotoxicity of TiO2 and Folate-Coupled Chitosan Nanoparticles Loading Polyprenol-Based Nanoemulsion

The structure and bioactivity of Ginkgo biloba leaves polyprenol (GBP) are similar to that of dolichol which widely exists in human and mammalian organs. GBP possesses potential pharmacological activities against cancer. This study involved oil-in-water type nanoemulsion (NE) loading GBP was prepared by dissolving polyprenol in nanoemulsion of sodium tripolyphosphate (TPP)/TiO₂ solution, Triton X-100, and 1-octanol by inversed-phase emulsification (EIP) and ultrasonic emulsification (UE) method. Folic acid (FA)-coupled chitosan (CS) nanoparticles (NPs), GBP-FA-CS-NPs and GBP-TiO₂-FA-CS-NPs, were fabricated by ionic cross-linking of positively charged FA-CS conjugates and negatively charged nanoemulsion with TPP/TiO₂. And characterizations of them were investigated by TEM, SEM, FTIR, particle size, and zeta potential. The cytotoxic and genotoxic effects of GBP-TiO₂-FA-CS-NP treatment were higher than GBP-NE, GBP-FA-CS-NPs, TiO₂-NE, GBP-TiO₂-NE, TiO₂-FA-CS-NPs, and GBP-TiO₂-FA-CS-NP treatment at the same tested concentrations in HepG2 cells. GBP-TiO₂-FA-CS-NPs at low TiO₂ concentration (from 1 to 2.5 μg/ml) showed good inhibition capacity on HepG2 cells and low cytotoxic and genotoxic effects on HL-7702 cells. The possible mechanism of cytotoxicity on GBP-TiO₂-FA-CS-NPs against HepG2 cells is by preventing excessive intracellular Ca²⁺ into extracellular spaces via inhibiting Ca²⁺-ATPase and Ca²⁺/Mg²⁺-ATPase.

Efficient extraction of proanthocyanidin from Ginkgo biloba leaves employing rationally designed deep eutectic solvent-water mixture and evaluation of the antioxidant activity

Proanthocyanidin (PAC) holds strong free radicals scavenging ability and is widely used as oxygen free radical scavenger. Huge demand, safety and economic aspect are forcing the PAC extraction to explore new resource and greener solvent. An efficient extraction method of PAC from Ginkgo biloba leaves was established by employing deep eutectic solvent (DES)-water mixture. After a rational design, a DES-water mixture (named as Ch-M₅₅) was chosen as the extraction solvent, which was prepared from choline chloride and malonic acid at a molar ratio of 1:2 with water addition of 55% (w/w). The main factors affecting the extraction yield were statistically optimized using a central composite design combined with response surface methodology (RSM). The optimal conditions were obtained as follows: extraction temperature of 65 °C, extraction time of 53 min and Ch-M₅₅ to solid ratio of 10.57:1 (v/w, mL/g). The PAC extraction yield was 22.19 ± 0.71 mg/g under the optimized conditions, which was much higher than those of conventional organic solvents. The antioxidant activity of PAC extracted by Ch-M₅₅ was similar to that of 70% acetone, but a little less than 70% methanol and 70% ethanol. The differences in constituent and polymerization degree of PAC extracted by different solvents might account for the difference in antioxidant activity. In consideration of biodegradability and pharmaceutical acceptability, the Ch-M₅₅-based extraction method is obviously efficient, green and ecofriendly. Extraction of PAC from Ginkgo biloba leaves also provides a new PAC resource.

Rapid Authentication of Ginkgo biloba Herbal Products Using the Recombinase Polymerase Amplification Assay

Species adulteration in herbal products (HPs) exposes consumers to health risks. Chemical and morphological methods have their own deficiencies when dealing with the detection of species containing the same active compounds in HPs. In this study, we developed a rapid identification method using the recombinase polymerase amplification (RPA) assay to detect two species, Ginkgo biloba and Sophora japonica (as adulteration), in Ginkgo biloba HPs. Among 36 Ginkgo biloba HP samples, 34 were found to have Ginkgo biloba sequences, and 9 were found to have Sophora japonica sequences. During the authentication process, the RPA-LFS assay showed a higher specificity, sensitivity and efficiency than PCR-based methods. We initially applied the RPA-LSF technique to detect plant species in HPs, demonstrating that this assay can be developed into an efficient tool for the rapid on-site authentication of plant species in Ginkgo biloba HPs.

In Silico Investigation of the Pharmacological Mechanisms of Beneficial Effects of Ginkgo biloba L. on Alzheimer's Disease

Based on compelling experimental and clinical evidence, Ginkgo biloba L. exerts a beneficial effect in ameliorating mild to moderate dementia in patients with Alzheimer’s disease (AD) and other neurological disorders, although the pharmacological mechanisms remain unknown. In the present study, compounds, their putative target proteins identified using an inverse docking approach, and clinically tested AD-related target proteins were systematically integrated together with applicable bioinformatics methods in silico. The results suggested that the beneficial effects of G. biloba on AD may be contributed by the regulation of hormone sensitivity, improvements in endocrine homeostasis, maintenance of endothelial microvascular integrity, and proteolysis of tau proteins, particularly prior to amyloid β-protein (Aβ) plaque formation. Moreover, we identified six putative protein targets that are significantly related to AD, but have not been researched or have had only preliminary studies conducted on the anti-AD effects of G. biloba. These mechanisms and protein targets are very significant for future scientific research. In addition, the existing mechanisms were also verified, such as the reduction of oxidative stress, anti-apoptotic effects, and protective effects against amyloidogenesis and Aβ aggregation. The discoveries summarized here may provide a macroscopic perspective that will improve our understanding of the molecular mechanism of medicinal plants or dietary supplements, as well as new clues for the future development of therapeutic strategies for AD.

Chromatogram-Bioactivity Correlation-Based Discovery and Identification of Three Bioactive Compounds Affecting Endothelial Function in Ginkgo Biloba Extract

Discovery and identification of three bioactive compounds affecting endothelial function in Ginkgo biloba Extract (GBE) based on chromatogram-bioactivity correlation analysis. Three portions were separated from GBE via D101 macroporous resin and then re-combined to prepare nine GBE samples. 21 compounds in GBE samples were identified through UFLC-DAD-Q-TOF-MS/MS. Correlation analysis between compounds differences and endothelin-1 (ET-1) in vivo in nine GBE samples was conducted. The analysis results indicated that three bioactive compounds had close relevance to ET-1: Kaempferol-3-O-α-l-glucoside, 3-O-{2-O-{6-O-[P-OH-trans-cinnamoyl]-β-d-glucosyl}-α-rhamnosyl} Quercetin isomers, and 3-O-{2-O-{6-O-[P-OH-trans-cinnamoyl]-β-d-glucosyl}-α-rhamnosyl} Kaempferide. The discovery of bioactive compounds could provide references for the quality control and novel pharmaceuticals development of GRE. The present work proposes a feasible chromatogram-bioactivity correlation based approach to discover the compounds and define their bioactivities for the complex multi-component systems.

The protective effect of Gingko biloba in a rat model of ovarian ischemia/reperfusion injury: Improvement in histological and biochemical parameters

BACKGROUND

Ovarian torsion is one of the most common gynecological emergencies, which especially affects women of reproductive age.

OBJECTIVES

We aimed to evaluate the effect of Ginkgo biloba (GB) supplementation in ovarian ischemia/ reperfusion injury in an experimental torsion/de-torsion rat model.

MATERIAL AND METHODS

This study was carried out in the Ege University Faculty of Medicine in Izmir, Turkey. Thirty mature female Sprague-Dawley albino rats were randomly divided into 5 groups: in Group 1 (control), the abdominal wall was only opened and closed; in the torsion group (Group 2), ischemia was induced for 3 h, using atraumatic vascular clips to create a torsion model; in the torsion/GB group (Group 3), the rats were given 80 mg/kg (oral gavage) of GB 30 min before torsion was induced and the torsion model was formed; in the torsion/de-torsion group (Group 4), the rats underwent 3 h of ischemia and then the vascular clips were removed and reperfusion took place for 3 h; in the torsion/de-torsion/GB group (Group 5), the rats underwent 3 h of ischemia followed by GB (oral gavage) 30 min prior to a 3-h reperfusion period. Ovarian tissue damage was evaluated by a histopathological scoring system. Ovarian tissue malondialdehyde (MDA) and plasma pentraxin-3 were measured.

RESULTS

In comparison with the sham group, both the torsion and torsion/de-torsion groups had significantly higher scores for follicular degeneration, vascular congestion, edema, hemorrhage, and leukocyte infiltration. Ginkgo biloba significantly decreased these scores in both groups. Ovarian malondialdehyde and plasma pentraxin 3 were significantly higher both in the torsion and torsion/de-torsion groups compared with the sham group. Ginkgo biloba decreased these levels significantly both in the torsion/GB and torsion/de-torsion/GB groups.

CONCLUSIONS

Supplementing GB during a surgical procedure decreases ischemia/reperfusion injury to an ovary in an experimental rat model based on histopathological parameters, tissue malondialdehyde, and plasma pentraxin-3 levels.

Quantification of terpene trilactones in Ginkgo biloba with a 1H NMR method

Ginkgo biloba L. has been used as a herbal medicine in the traditional treatment of insufficient blood flow, memory deficits, and cerebral insufficiency. The terpene trilactone components, the bioactive agents of Ginkgo biloba L., have also been reported to exhibit useful functionality such as anti-inflammatory and neuroprotective effects. Therefore, in the present research, we attempted to analyze quantitatively the terpene trilactone components in Ginkgo biloba leaf extract, with quantitative ¹H NMR (qNMR) and obtained almost identical results to data reported using HPLC. Application of the qNMR method for the analysis of the terpene trilactone contents in commercial Ginkgo extract products, such as soft gel capsules and tablets, produced the same levels noted in package labels. Thus, qNMR is an alternative method for quantification of the terpene trilactone components in commercial Ginkgo extract products.

Herbal medicine for sports: a review

The use of herbal medicinal products and supplements has increased during last decades. At present, some herbs are used to enhance muscle strength and body mass. Emergent evidence suggests that the health benefits from plants are attributed to their bioactive compounds such as Polyphenols, Terpenoids, and Alkaloids which have several physiological effects on the human body. At times, manufacturers launch numerous products with banned ingredient inside with inappropriate amounts or fake supplement inducing harmful side effect. Unfortunately up to date, there is no guarantee that herbal supplements are safe for anyone to use and it has not helped to clear the confusion surrounding the herbal use in sport field especially. Hence, the purpose of this review is to provide guidance on the efficacy and side effect of most used plants in sport. We have identified plants according to the following categories: Ginseng, alkaloids, and other purported herbal ergogenics such as Tribulus Terrestris, Cordyceps Sinensis. We found that most herbal supplement effects are likely due to activation of the central nervous system via stimulation of catecholamines. Ginseng was used as an endurance performance enhancer, while alkaloids supplementation resulted in improvements in sprint and cycling intense exercises. Despite it is prohibited, small amount of ephedrine was usually used in combination with caffeine to enhance muscle strength in trained individuals. Some other alkaloids such as green tea extracts have been used to improve body mass and composition in athletes. Other herb (i.e. Rhodiola, Astragalus) help relieve muscle and joint pain, but results about their effects on exercise performance are missing.