Rapid Screening of Chemical Components in Salvia miltiorrhiza with the Potential to Inhibit Skin Inflammation.

Hyaluronidase possesses the capacity to degrade high-molecular-weight hyaluronic acid into smaller fragments, subsequently initiating a cascade of inflammatory responses and activating dendritic cells. In cases of bacterial infections, substantial quantities of HAase are generated, potentially leading to severe conditions such as cellulitis. Inhibiting hyaluronidase activity may offer anti-inflammatory benefits. Salvia miltiorrhiza Bunge, a traditional Chinese medicine, has anti-inflammatory properties. However, its effects on skin inflammation are not well understood. This study screened and evaluated the active components of S. miltiorrhiza that inhibit skin inflammation, using ligand fishing, enzyme activity assays, drug combination analysis, and molecular docking. By combining magnetic nanomaterials with hyaluronidase functional groups, we immobilized hyaluronidase on magnetic nanomaterials for the first time in the literature. We then utilized an immobilized enzyme to specifically adsorb the ligand; two ligands were identified as salvianolic acid B and rosmarinic acid by HPLC analysis after desorption of the dangling ligands, to complete the rapid screening of potential anti-inflammatory active ingredients in S. miltiorrhiza roots. The median-effect equation and combination index results indicated that their synergistic inhibition of hyaluronidase at a fixed 3:2 ratio was enhanced with increasing concentrations. Kinetic studies revealed that they acted as mixed-type inhibitors of hyaluronidase. Salvianolic acid B had Ki and Kis values of 0.22 and 0.96 µM, respectively, while rosmarinic acid had values of 0.54 and 4.60 µM. Molecular docking revealed that salvianolic acid B had a higher affinity for hyaluronidase than rosmarinic acid. In addition, we observed that a 3:2 combination of SAB and RA significantly decreased the secretion of TNF-α, IL-1, and IL-6 inflammatory cytokines in UVB-irradiated HaCaT cells. These findings identify salvianolic acid B and rosmarinic acid as key components with the potential to inhibit skin inflammation, as found in S. miltiorrhiza. This research is significant for developing skin inflammation treatments. It demonstrates the effectiveness and broad applicability of the magnetic nanoparticle-based ligand fishing approach for screening enzyme inhibitors derived from herbal extracts.

Screening of monoamine oxidase B inhibitors in Tibetan strawberry by ligand fishing based on enzyme functionalized cellulose filter paper.

Tibetan strawberry (Fragaria nubicola) is a wild medicinal and edible plant in Tibet possessing various health benefits such as neuroprotection and anti-oxidation. However, there has been little study reported on its chemical constituents. To investigate the inhibitors of monoamine oxidase B (MAO-B) in Tibetan strawberry, we immobilized the enzyme onto cellulose filter paper for the first time to develop a new screening method. Two known glycosides (compounds 1 and 2) and one new iridoid glucoside (Compound 3) were fished out by this method, which was found to effectively inhibit MAO-B with IC50 values of 16.95 ± 0.93, 24.69 ± 0.20, and 46.77 ± 0.78 µM, respectively. Molecular docking and kinetic analysis were performed to reveal the inhibition mechanism of these compounds. Furthermore, compound 1 exhibited neuroprotective effects against 6-OHDA-induced injury on PC12 cells. The developed method exhibits the advantages of rapidness and effectiveness in screening of MAO-B inhibitors from complex herbal extracts.

An on-line SPE-LC-MS/MS method for quantification of nucleobases and nucleosides present in biological fluids.

Solid phase extraction (SPE) and liquid chromatographic (LC) separation of nucleobases and nucleosides are challenging due to the high hydrophilicity of these compounds. Herein we report a novel on-line SPE-LC-MS/MS method for their quantification after pre-column derivatization with chloroacetaldehyde (CAA). The method proposed is selective and sensitive with limits of detection at the nano-molar level. Analysis of urine and saliva samples by using this method is demonstrated. Adenine, guanine, cytosine, adenosine, guanosine, and cytidine were found in the range from 0.19 (guanosine) to 1.83 µM (cytidine) in urine and from 0.015 (guanosine) to 0.79 µM (adenine) in saliva. Interestingly, methylation of cytidine was found to be significantly different in urine from that in saliva. While 5-hydroxymethylcytidine was detected at a very low level (<0.05 µM) in saliva, it was found to be the most prominent methylated cytidine in urine at a high level of 3.33 µM. Since on-line SPE is deployed, the proposed LC-MS/MS quantitative assay is convenient to carry out and offers good assay accuracy and repeatability.

Clinical Reasoning: A 30-Year-Old Woman Presenting With Rapidly Progressive Dementia and Extreme Hypoglycorrhachia.

A 30-year-old woman presented with rapidly progressive dementia 1 month after the coronavirus disease 2019 infection. Repeated CSF analysis showed extreme hypoglycorrhachia, while cultures, metagenomic next-generation sequencing, and cytopathology testing of CSF were negative. Laboratory investigations for possible etiologies revealed elevated blood ammonia and cancer antigen 125. Brain MRI demonstrated bilateral symmetric diffuse cortical lesions with mild hyperintensity on T1-weighted image and postcontrast enhancement. A more thorough history and specific examinations subsequently indicated an underlying etiology. This case provides an approach for evaluating young patients with rapidly progressive dementia, extreme hypoglycorrhachia, and diffuse CNS lesions, highlighting the importance of considering a broad differential diagnosis.

Quassinoids from Twigs of Harrisonia perforata (Blanco) Merr and Their Anti-Parkinson's Disease Effect.

Six new C-20 and one new C-19 quassinoids, named perforalactones F-L (1-7), were isolated from twigs of Harrisonia perforata. Spectroscopic and X-ray crystallographic experiments were conducted to identify their structures. Through oxidative degradation of perforalactone B to perforaqussin A, the biogenetic process from C-25 quassinoid to C-20 via Baeyer-Villiger oxidation was proposed. Furthermore, the study evaluated the anti-Parkinson's disease potential of these C-20 quassinoids for the first time on 6-OHDA-induced PC12 cells and a Drosophila Parkinson's disease model of PINK1B9. Perforalactones G and I (2 and 4) showed a 10-15% increase in cell viability of the model cells at 50 µM, while compounds 2 and 4 (100 µM) significantly improved the climbing ability of PINK1B9 flies and increased the dopamine level in the brains and ATP content in the thoraces of the flies.

Characteristics of multi-channel intermuscular directional coupling based on time-varying partial directional coherence analysis.

The human body transmits directional information between muscles during upper limb movements, and this will be particularly evident when the dominant muscle changes during movement transitions. By capturing the electromyography (EMG) signals of wrist flexion and extension continuous transition movements, we investigated the characteristics of multichannel intermuscular directional coupling and directional information transmission, and consequently explored the control mechanism of Central nervous system (CNS) and the coordination mechanism of motor muscles. Multi-channel EMG was collected from 12 healthy subjects under continuous translational movements of wrist flexion and extension, and the time-varying biased directional coherence analysis (TVPDC) model was constructed using partial directional coherence analysis (PDC) frequency domain directionality to study the directional information transfer characteristics in the time-frequency domain, screen closely related muscle pairs and perform directional coupling significance analysis. Palmaris longus (PL) played a dominant role under wrist flexion movements(WF), Extensor Carpi Radialis (ECR) played a dominant role under wrist extension movements(WE), and the remaining muscles responded to them with information and Biceps Brachii (BB) played a responsive role throughout the movement; flexor pairs had the highest positive coupling values in the beta band during Conversion action1 (MC1) and WF phases, and extensor pairs had the highest positive coupling values in the gamma band during Conversion action2(MC2) phase and the highest coupling values in the beta band during WE phase. TVPDC can effectively analyze the multichannel intermuscular directional coupling and information transmission relationship of surface electromyography under wrist flexion and extension transition movements, providing a reference for exploring the control mechanism of CNS and abnormal control mechanism in patients with motor dysfunction in a new perspective.

Chemical constituents from leaves of Jatropha curcas.

Objective: To investigate the chemical constituents from the leaves of Jatropha curcas and evaluate their inhibition on lipopolysaccharide (LPS)-activated BV-2 microglia cells. Methods: The n-BuOH extract of the leaves of J. curcas was isolated by macroporous adsorption resin, silica gel, ODS, column chromatography and semi-preparative HPLC. The structures of the compounds were identified by MS, NMR, ECD, and other spectroscopic methods. In addition, anti-neuroinflammatory effects of isolated compounds were evaluated by measuring the production of nitric oxide (NO) in over-activated BV-2 cells. Results: Seventeen compounds, including (7R,8S)-crataegifin A-4-O-ß-D-glucopyranoside (1), (8R,8'R)-arctigenin (2), arctigenin-4'-O-ß-D-glucopyranoside (3), (-)-syringaresinol (4), syringaresinol-4'-O-ß-D-glucopyranoside (5), (-)-pinoresinol (6), pinoresinol-4'-O-ß-D-glucopyranoside (7), buddlenol D (8), (2R,3R)-dihydroquercetin (9), (2S,3S)-epicatechin (10), (2R,3S)-catechin (11), isovitexin (12), naringenin-7-O-ß-D-glucopyranoside (13), chamaejasmin (14), neochamaejasmin B (15), isoneochamaejasmin A (16), and tomentin-5-O-ß-D-glucopyranoside (17) were isolated and identified. Compounds 2, 4 and 8 significantly inhibited the release of NO in BV-2 microglia activated by LPS, with IC50 values of 18.34, 29.33 and 26.30 µmol/L, respectively. Conclusion: Compound 1 is a novel compound, and compounds 2, 3, 8, 14-17 are isolated from Jatropha genus for the first time. In addition, the lignans significantly inhibited NO release and the inhibitory activity was decreased after glycosylation.

Polyphenolic glycosides with unusual four-membered ring possessing anti-Parkinson's disease potential from black wolfberry.

This work reports the isolation of seven undescribed polyphenolic glycosides (1-7) together with fourteen known compounds (8-21) from the fruit of Lycium ruthenicum Murray. The structures of the undescribed compounds were identified based on comprehensive spectroscopic methods including IR, HRESIMS, NMR and ECD, and chemical hydrolysis. Compounds 1-3 possess an unusual four-membered ring, while 11-15 were firstly isolated from this fruit. Interestingly, compounds 1-3 inhibited monoamine oxidase B with IC50 of 25.36 ± 0.44, 35.36 ± 0.54, and 25.12 ± 1.59 µM, respectively, and showed significant neuroprotective effect on PC12 cells injured by 6-OHDA. Moreover, compound 1 improved the lifespan, dopamine level, climbing behavior, and olfactory ability of the PINK1B9 flies, a Drosophila model of Parkinson's disease. This work presents the first in vivo neuroprotective evidence of the small molecular compounds in L. ruthenicum Murray fruit, indicating its good potential as neuroprotectant.

Association of cataract extraction and the risk of dementia-A systematic review and meta-analysis.

Objectives: This research aims to investigate if cataract extraction lowers the risk of all-cause dementia. Methods: Original literature on cataract surgery associated with all-cause dementia as of November 27, 2022, was searched in several commonly used databases. Manual review was used to include eligible studies. Stata software (version 16) was used to perform statistical analysis on pertinent data. Publication bias can be precisely evaluated using funnel plots and Egger's test. Results: In the meta-analysis of 4 cohort studies with 245,299 participants. Pooled analysis indicated that cataract surgery was linked to a lower incidence of all-cause dementia (OR = 0.77, 95%CI: 0.66-0.89; I2= 54.7%; P < 0.001). Cataract surgery was linked to a lower risk of AD (OR = 0.60, 95%CI: 0.35-1.02; I2= 60.2%; P < 0.001). Conclusions: Cataract surgery is linked to a lower incidence of all-cause dementia and Alzheimer's disease. A cataract is a reversible visual impairment. Cataract surgery may be a protective factor against the onset of all-cause dementia and can reduce the economic and family burden caused by all-cause dementia worldwide. Given the restricted pool of included studies, our findings necessitate meticulous interpretation. Systematic review registration: http://www.crd.york.ac.uk/prospero retrieve registration details by searching CRD4202379371.

Screening of Monoamine Oxidase Inhibitors from Seeds of Nigella glandulifera Freyn et Sint. by Ligand Fishing and Their Neuroprotective Activity.

Nigella glandulifera is a traditional medicinal plant used to treat seizures, insomnia, and mental disorders among the Tibetan and Xinjiang people of China. Recent pharmacological research indicates that the seeds of this plant have a neuroprotective effect; however, the chemical components responsible for this effect are unknown. Monoamine oxidase B (MAO-B) has been recognized as a target for developing anti-Parkinson's disease drugs. In this work, MAO-B functionalized magnetic nanoparticles were used to enrich the enzyme's ligands in extracts of N. glandulifera seeds for rapid screening of MAO-B inhibitors coupled with HPLC-MS. Tauroside E and thymoquinone were found to inhibit the enzyme with IC50 values of 35.85 µM and 25.54 µM, respectively. Both compounds exhibited neuroprotective effects on 6-OHDA-induced PC-12 cells by increasing the cell viability to 52% and 58%, respectively, compared to 50% of the injured cells. Finally, molecular docking indicated strong interactions of both inhibitors with the enzyme. This work shows that MAO-B functionalized magnetic nanoparticles are effective for rapid screening of anti-PD inhibitors from complex herbal mixtures and, at the same time, shows the promising potential of this plant's seeds in developing anti-PD drugs.

A novel one-pot fluorescence tagging and depyrimidination strategy for quantification of global DNA methylation.

DNA methylation is intensively studied in medical science. Current HPLC methods for quantification of global DNA methylation involve digestion of a DNA sample and HPLC determination of both cytosine (C) and 5-methylcytosine (5mC) so that percentage of 5mC in total cytosine can be calculated as DNA methylation level. Herein we report a novel HPLC method based on a one-pot fluorescence tagging and depyrimidination reaction between DNA and chloroacetaldehyde (CAA) for highly sensitive quantification of global DNA methylation. In the one-pot reaction, C and 5mC residues in a DNA sequence react with CAA, forming fluorescent etheno-adducts that are then released from the sequence through depyrimidination. Interestingly, etheno-5mC (ε-5mC) is ∼20 times more fluorescent than ε-C and other ε-nucleobases resulting from the reaction, which greatly facilitates the quantification. Further, due to the tagging-induced increase in structural aromaticity, ε-nucleobases are far more separable by HPLC than intact nucleobases. The proposed HPLC method with fluorescence detection (HPLC-FD) is quick (i.e., < 1h per assay) and highly sensitive with a detection limit of 0.80 nM (or 250 fg on column) for 5mC. Using the method, DNA samples isolated from yeast, HCT-116 cells, and tissues were analyzed. Global DNA methylation was measured to be in the range from 0.35% to 2.23% in the samples analyzed. This sensitive method allowed accurate analyses of minute DNA samples (∼100 ng) isolated from milligrams of tissues.

Impact of high-sensitivity troponin elevation and dynamic changes on 90-day mortality in patients with acute ischemic stroke after mechanical thrombectomy: results from an observational cohort.

BACKGROUND: A study was undertaken to evaluate the impact of high-sensitivity cardiac troponin I (hs-cTnI) elevation and hs-cTnI dynamic changes on 90-day mortality in patients with acute ischemic stroke (AIS) treated with mechanical thrombectomy (MT). METHODS: Patients with AIS receiving MT were included in the study. Sixty hours after AIS onset, hs-cTnI levels were measured before and after MT to determine elevated and dynamic changes. Patients were stratified into either normal or hs-cTnI elevation groups according to the pre-MT hs-cTnI cut-off value of 0.03 ng/L. hs-cTnI dynamic changes were defined as an increase or decrease of more than 20% pre-MT and post-MT, and at least one hs-cTnI level >0.03 ng/L. Multivariate Cox regression models were used to investigate the association between hs-cTnI elevation, hs-cTnI dynamic changes, and 90-day mortality in patients with AIS after MT. RESULTS: A total of 423 patients with AIS after MT were included in our final analysis, of whom only 72 (17%) showed hs-cTnI elevation. Post-MT hs-cTnI retesting was performed in 354 patients, and 90 (25.4%) patients presented with hs-cTnI dynamic changes. 119 patients died within 90 days. After adjusting for potential confounding factors, the Cox regression model showed that patients with hs-cTnI dynamic changes, rather than hs-cTnI elevation, were associated with 90-day mortality (p<0.05). Compared with the hs-cTnI non-dynamic changes, these results showed that a statistical association was present between rising hs-cTnI dynamic changes and 90-day mortality (p>0.05). CONCLUSIONS: hs-cTnI dynamic changes, dominated by the rising pattern rather than hs-cTnI elevation, were independent factors associated with 90-day mortality in patients with AIS after MT, especially in elderly subjects.

Screening of Monoamine Oxidase B Inhibitors from Fragaria nubicola by Ligand Fishing and Their Neuroprotective Effects.

Fragaria nubicola, known as Tibetan strawberry, is an edible plant possessing various health-promoting effects. However, its functional compositions were rarely studied. In this work, monoamine oxidase B (MAO-B) inhibitors in this plant were rapidly screened using the enzyme-functionalized magnetic nanoparticles coupled with UPLC-QTOF-MS. Two inhibitors, quercetin-3-O-ß-d-glucuronide-6″-methyl ester (1) and kaempferol-3-O-ß-d-glucuronide-6″-methyl ester (2), were identified from this plant with the IC50 values of 19.44 ± 1.17 and 22.63 ± 1.78 µM, respectively. Enzyme kinetic analysis and molecular docking were carried out to investigate the mechanism of inhibition. Contents of both compounds as well as those of total phenolics and flavonoids were quantified to be 24.76 ± 1.26, 35.59 ± 1.17, 837.67 ± 10.62, and 593.46 ± 10.37 µg/g, respectively. In addition, both compounds exhibited significant neuroprotective effects on 6-hydroxydopamine-induced PC12 cells. This is the first report on the neuroprotective components of F. nubicola, suggesting its potential for developing neuroprotective functional food.

Ligand fishing of monoamine oxidase B inhibitors from Platycodon grandiflorus (Jacq.) A.DC. roots by the enzyme functionalised magnetic nanoparticles.

INTRODUCTION: As a famous traditional Chinese medicine, roots of Platycodon grandiflorus (Jacq.) A.DC. have shown multiple effects against neurodegenerative diseases. To investigate the components against Parkinson's disease (PD), the roots of P. grandiflora were selected as the research subject. OBJECTIVE: Screening and identifying of monoamine oxidase B (MAO-B) inhibitors from the roots of P. grandiflorum via enzyme functionalised magnetic nanoparticles (MNPs)-based ligand fishing combined with high-performance liquid chromatography-mass spectrometry (HPLC-MS) analysis. METHOD: MAO-B functionalised MNPs have been synthesised for screening MAO-B inhibitors from the roots of P. grandiflorum. The ligands were identified by HPLC-MS and nuclear magnetic resonance (NMR) analysis, and their anti-PD activity was evaluated via MAO-B inhibition assay and cell viability assay in vitro. RESULTS: Two MAO-B inhibitors were fished out and identified by HPLC-MS as protocatechuic aldehyde (1) and coumarin (2), with the half maximal inhibitory concentrations of 28.54 ± 0.39 and 25.39 ± 0.29 µM, respectively. Among them, 1 could also significantly increase the viability of 6-hydroxydopamine-damaged PC12 cells. CONCLUSION: The results are helpful to elucidate the anti-PD activity of the plant, and the ligand fishing method has shown good potential in discovery of MAO-B inhibitors.

Study on the interaction mechanism between Crocus sativus and Fusarium oxysporum based on dual RNA-seq.

KEY MESSAGE: The saffron phenylpropane synthesis pathway and Fusarium oxysporum cell wall-degrading enzymes play key roles in their early interactions. Saffron (Crocus sativus) is a highly important crop with diverse medicinal properties. F. oxysporum is a widely-distributed soil-borne fungus, causing the serious saffron rot disease. Currently, there is no effective management strategy to control this disease because of no resistant cultivars and limited information about the resistance and pathogenic mechanisms. In this study, we first characterized the infection process and physiological responses of saffron infected by F. oxysporum. The molecular mechanism of these infection interactions was revealed by dual RNA-seq analysis. On the 3rd day of infection, the hyphae completely entered, colonized and spread in the corm cells; while on the 6th day of infection, hyphae had appeared in the xylem cells, blocking these vessels. Transcriptome results indicate that within the host, phenylpropanoid metabolism, plant hormone signal transduction and plant pathogen interaction pathways were activated during infection. These pathways were conducive to the enhancement of cell wall, the occurrence of hypersensitivity, and the accumulation of various antibacterial proteins and phytoantitoxins. Meanwhile, in the fungus, many up-regulated genes were related to F. oxysporum cell wall degrading enzymes, toxin synthesis and pathogenicity gene, showing its strong pathogenicity. This study provides new ideas for the control of saffron corm rot, and also provides a theoretical basis for mining the key functional genes.

Neuroprotective Effects of Lycium Barbarum Fruit Extract on Pink1B9Drosophila Melanogaster Genetic Model of Parkinson's Disease.

Lycium barbarum (LB) is a famous traditional Chinese medicinal plant as well as food supplement possessing various pharmacological functions such as anti-aging and antioxidant effects. The Parkinson's disease (PD)-related kinase Pink1 plays vital role in maintaining the neuron cell homeostasis, having been recognized as a potential target for the development of anti-PD drugs. In this work, the neuroprotective effects of methanol extract of LB fruit (LBFE) were investigated using a Drosophila PD model (PINK1B9) and a human neuroblastoma SH-SY5Y cell line. We found that when LBFE was supplied to the PINK1B9 flies at 6, 12, and 18 days of age, it raised the ATP and dopamine levels at all ages, extended life span, improved motor behavior, and rescued olfactory deficits of the PINK1B9 flies. In addition, histopathological examinations indicated that muscle atrophy in thoraces of the mutant flies was significantly repaired. Finally, LBFE was able to rescue the SH-SY5Y cells against MPP+-induced neurotoxicity. This work reports for the first time the anti-PD potential of L. barbarum fruit extract in PINK1 mutant fruit flies, presenting a new viewpoint for studing the mechanism of action of LBFE.

Fast Screening of Protein Tyrosine Phosphatase 1B Inhibitor from Salvia miltiorrhiza Bge by Cell Display-Based Ligand Fishing.

Salvia miltiorrhiza Bge is a medicinal plant (Chinese name "Danshen") widely used for the treatment of hyperglycemia in traditional Chinese medicine. Protein tyrosine phosphatase 1B (PTP1B) has been recognized as a potential target for insulin sensitizing for the treatment of diabetes. In this work, PTP1B was displayed at the surface of E. coli cells (EC-PTP1B) to be used as a bait for fishing of the enzyme's inhibitors present in the aqueous extract of S. miltiorrhiza. Salvianolic acid B, a polyphenolic compound, was fished out by EC-PTP1B, which was found to inhibit PTP1B with an IC50 value of 23.35 µM. The inhibitory mechanism of salvianolic acid B was further investigated by enzyme kinetic experiments and molecular docking, indicating salvianolic acid B was a non-competitive inhibitor for PTP1B (with Ki and Kis values of 31.71 µM and 20.08 µM, respectively) and its binding energy was -7.89 kcal/mol. It is interesting that in the comparative work using a traditional ligand fishing bait of PTP1B-immobilized magnetic nanoparticles (MNPs-PTP1B), no ligands were extracted at all. This study not only discovered a new PTP1B inhibitor from S. miltiorrhiza which is significant to understand the chemical basis for the hypoglycemic activity of this plant, but also indicated the effectiveness of cell display-based ligand fishing in screening of active compounds from complex herbal extracts.

Clinical Application of Thromboelastography in Acute Ischemic Stroke.

Acute ischemic stroke (AIS), characterized by high morbidity and mortality, has imposed a considerable burden on society. Despite rapid development in the treatment of AIS, there is still a high risk of recurrence. Furthermore, there is a time delay in waiting for the results of conventional coagulation tests in candidate patients for intravenous thrombolysis therapy. Heterogeneous responses to antiplatelet, intravascular thrombolysis, and endovascular therapies also worsen the situation. Thromboelastography (TEG), as a global and portable detection method for hemostasis, facilitates clinicians in disease monitoring, treatment evaluation, and prognosis prediction in AIS. In this narrative review, we provided a comprehensive summary of the clinical application of TEG in ischemic stroke and gave insights to further studies.

Tyrosinase covalently immobilized on carboxyl functionalized magnetic nanoparticles for fishing of the enzyme's ligands from Prunellae Spica.

In this study, tyrosinase was immobilized on carboxyl functionalized silica-coated magnetic nanoparticles for the first time to be used for fishing of tyrosinase's ligands present in complex plant extract. The immobilized tyrosinase was characterized by transmission electron microscopy, vibrating sample magnetometry, Fourier transform infrared spectroscopy, thermo-gravimetric analyzer, and atomic force microscopy. The reusability and thermostability of the immobilized tyrosinase were found significantly superior to its free counterpart. Two tyrosinase's ligands, that is, caffeic acid (1) and rosmarinic acid (2), were fished out from extract of the traditional Chinese medicine Prunellae Spica by the immobilized tyrosinase. Compound 1 was found to be an activator of the enzyme with the half maximal effective concentration value of 0.27 ± 0.06 mM, while compound 2 was an inhibitor with the half maximal inhibitory concentration value of 0.14 ± 0.03 mM. Taking advantage of the convenience of magnetic separation and specific extraction ability of ligand fishing, the proposed method exhibited great potential for screening of bioactive compounds from complex matrices.

Polyphenolic Glycosides from the Fruits Extract of Lycium ruthenicum Murr and Their Monoamine Oxidase B Inhibitory and Neuroprotective Activities.

The fruits ofLycium ruthenicum Murr have long been consumed as health food and used in folk medicine in China. Apart from the well-known polysaccharides, the active small molecular constituents in this fruit have not been fully studied. In this work, a systematic phytochemical study was carried out to investigate the small molecules and their potential health benefits. Nine new polyphenolic glycosides, lyciumserin A-I (1-9), together with 16 known compounds (10-25), were isolated and elucidated by high-resolution electrospray ionization mass spectrometry and comprehensive NMR analyses in combination with chemical hydrolysis. Compounds 1, 2, and 16 exhibited moderate inhibitory activity of monoamine oxidase B (MAO-B), while compounds 1 (50 µM) and 2 (100 µM) displayed significant neuroprotective effects (69.22 and 72.38% of cell viability, respectively) in the 6-hydroxydopamine-induced injury of the PC12 cell model (54.41%), comparable to the positive drug rasagiline (70.45%). The neuroprotective effect of 1 and 2 was further evidenced by the observation of the morphological change and fluorescein diacetate/propidium iodide staining. In addition, the levels of the major active compounds (1, 3, 5/6, and 16-18) vary from 21.5 to 892.3 µg/g. This is the first report on phenolic glycosides from the fruits ofL. ruthenicum Murr that possess both significant MAO-B inhibitory and neuroprotective effects, indicating the promising potential of the fruits for the development of health care products and even therapeutic agents for the treatment of Parkinson's disease and other neurodegenerative diseases.