Screening and identification of BSA bound ligands from Puerariae lobata flower by BSA functionalized Fe3O4 magnetic nanoparticles coupled with HPLC–MS/MS

Two-dimensional chromatography in screening of bioactive components from natural products

INTRODUCTION

Screening and analysis of bioactive components from natural products is a fundamental part of new drug development and innovation. Two-dimensional (2D) chromatography has been demonstrated to be an effective method for screening and preparation of specific bioactive components from complex natural products.

OBJECTIVE

To collect details of application of 2D chromatography in screening of natural product bioactive components and to outline the research progress of different separation mechanisms and strategies.

METHODOLOGY

Three screening strategies based on 2D chromatography are reviewed, including traditional separation-based screening, bioactivity-guided screening and affinity chromatography-based screening. Meanwhile, in order to cover these aspects, selections of different separation mechanisms and modes are also presented.

RESULTS

Compared with traditional one-dimensional (1D) chromatography, 2D chromatography has unique advantages in terms of peak capacity and resolution, and it is more effective for screening and identifying bioactive components of complex natural products.

CONCLUSION

Screening of natural bioactive components using 2D chromatography helps separation and analysis of complex samples with greater targeting and relevance, which is very important for development of innovative drug leads.

The Potential Therapeutic Properties of Prunetin against Human Health Complications: A Review of Medicinal Importance and Pharmacological Activities

BACKGROUND

Flavonoids are polyphenolic compounds found to be present in nature and abundant in flowers and fruits. Flavonoidal class phytochemicals have gained interest in the scientific field because of their important pharmacological activities. Several scientific studies have revealed anti-bacterial, anti-oxidant, anti-fungal, analgesic, anti-viral, anti-inflammatory, anti-tumor, anti-parasitic and anti-allergic activities of flavonoidal class phytochemicals. Prunetin is an O-methylated isoflavone that belongs to the phytochemical phytoestrogen class, found to be present in licorice, red cherry, soybean and legumes.

METHODS

Biological potential and pharmacological activities of prunetin have been investigated in the present work through scientific data analysis of numerous scientific research works. Numerous literature databases have been searched in order to collect the scientific information on prunetin in the present work. Pharmacological activities of prunetin have been investigated in the present work through literature data analysis of different scientific research works. Scientific data have been collected from Google Scholar, Google, PubMed, Science Direct and Scopus. Analytical data on prunetin has been collected from literature sources and analyzed in the present work.

RESULTS

Scientific data analysis revealed the biological importance of prunetin in medicine. Prunetin was found to be present in the pea, peach, Oregon cherry, skimmed cheese, cheese, cow kefir and goat kefir. Prunetin is also present in the Prunus avium, Andira surinamensis, Butea superba, Dalbergia sympathetica, Ficus nervosa, Pterospartum tridentatum and Pycnanthus angolensis. Pharmacological data analysis revealed the biological importance of prunetin on bone disorders, cancers, especially hepatocellular carcinoma, urinary bladder cancer, gastric cancer, ovarian cancer, human airway, gut health and enzymes. Scientific data analysis revealed biological effectiveness of prunetin for their angiogenic effects, anti-inflammatory, anti-oxidant, antimicrobial, estrogenic and vasorelaxant potential. Analytical data revealed the importance of modern analytical techniques for qualitative and quantitative analysis of prunetin in the scientific fields.

CONCLUSION

Scientific data analysis in the present investigation revealed the biological importance and pharmacological activities of prunetin in medicine.

Flos puerariae ameliorates the intestinal inflammation of Drosophila via modulating the Nrf2/Keap1, JAK-STAT and Wnt signaling

Gut homeostasis is important for human health, and its disruption can lead to inflammatory bowel disease (IBD). Flos Puerariae is a herb with a wide variety of pharmacological activities including antioxidant, antidiabetic, antialcoholismic and anti-inflammatory properties. However, the role of Flos Puerariae on treating IBD remains obscure. Here, we employed Drosophila melanogaster as a model organism to investigate the protective effect of Flos Puerariae extract (FPE) against sodium dodecyl sulfate (SDS)-induced intestinal injury. Our data showed that FPE had no toxic effect in flies, and significantly extended lifespan in SDS-inflamed flies, reduced stem cell proliferation in the midgut, and maintained intestinal morphological integrity. Furthermore, FPE remarkably recused the altered expression level of genes and proteins in Nrf2/Keap1 signaling, JAK-STAT signaling and Wnt signaling pathways in gut of inflammation flies. Thus, FPE has a protective effect against intestinal injury possibly via increasing the Nrf2/keap1 pathway and suppressing the JAK-STAT and Wnt signaling pathways, which would have tremendous potential for treating IBD.

Medicinal Importance, Pharmacological Activities and Analytical Aspects of an Isoflavone Glycoside Tectoridin

Background:

Polyphenols are a group of plant secondary metabolites that are produced in plants as a protective system against oxidative stress, UV radiation, pathogens and predator’s attack. Flavonoids are major class of plant phenolics found to be present in fruits, vegetables, tea and red wine. Tectoridin also called 40,5,7-thrihydroxy-6-methoxyisoflavone-7-Ob-D-glucopyranoside is an isoflavone glycoside found to be present in the flower of Porites lobata.

Methods:

Present work focused on the biological importance, therapeutic potential and pharmacological activities of tectoridin in medicine. Numerous scientific data has been collected from different literature databases such as Google Scholar, Science Direct, PubMed and Scopus in order to know the health beneficial potential of tectoridin. Pharmacological data have been analyzed in the present work to know the biological effectiveness of tectoridin against human disorders. Analytical data of tectoridin have been collected and analyzed in the present work in order to know the importance of modern analytical method in the isolation, separation and identification of tectoridin.

Results:

Scientific data analysis revealed the biological importance and therapeutic benefit of tectoridin in medicine, signifying the therapeutic potential of tectoridin in the healthcare systems. Biological activities of tectoridin are mainly due to its anti-inflammatory, anti-platelet, anti-angiogenic, hepatoprotective, anti-tumor, estrogenic, antioxidant and hypoglycemic activity. However effectiveness of tectoridin against rat lens aldose reductase, nitric oxide, skeletal and cardiac muscle sarcoplasmic reticulum and enzymes have been also presented in this work. Analytical data signified the importance of modern analytical techniques for the separation, identification and isolation of tectoridin.

Conclusion:

Present work signified the biological importance and therapeutic benefit of tectoridin in the medicine and other allied health sectors.

Advances in Magnetic Microbead Affinity Selection Screening: Discovery of Natural Ligands to the SARS-CoV-2 Spike Protein

Affinity selection-mass spectrometry, which includes magnetic microbead affinity selection-screening (MagMASS), is ideal for the discovery of ligands in complex mixtures that bind to pharmacological targets. Therapeutic agents are needed to prevent or treat COVID-19, which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Infection of human cells by SARS-CoV-2 involves binding of the virus spike protein subunit 1 (S1) to the human cell receptor angiotensin converting enzyme-2 (ACE2). Like antibodies, small molecules have the potential to block the interaction of the viral S1 protein with human ACE2 and prevent SARS-CoV-2 infection. Therefore, a MagMASS assay was developed for the discovery of ligands to the S1 protein. Unlike previous MagMASS approaches, this new assay used robotics for 5-fold enhancement of throughput and sensitivity. The assay was validated using the SBP-1 peptide, which is identical to the ACE2 amino acid sequence recognized by the S1 protein, and then applied to the discovery of natural ligands from botanical extracts. Small molecule ligands to the S1 protein were discovered in extracts of the licorice species, Glycyrrhiza inflata. In particular, the licorice ligand licochalcone A was identified through dereplication and comparison with standards using HPLC with high-resolution tandem mass spectrometry.

Herbal Phytomedicine 'Irisolidone' in Chronic Diseases: Biological Efficacy and Pharmacological Activity

BACKGROUND

Plant-derived products have been used in medicine as a source of bioactive molecules, mainly due to their medicinal importance and therapeutic potential. Nowadays, plant derived products have been used in the medicine for the development of novel drug leads. Polyphenols are an important class of secondary metabolites found to be present in plants and their derived products. Polyphenols play an important role in the nutrition of human beings and also have a significant role in plant resistance against pests and diseases. Scientific studies have proven the biological importance of flavonoids in medicine and other allied health sectors. Anti-oxidant, analgesic, anti-microbial, anti-inflammatory, anti-viral, anti-tumor and anti-allergic activities are the important pharmacological features of flavonoids. Irisolidone is an important isoflavone found to be present in Pueraria lobata flowers.

METHODS

To know the medicinal importance and therapeutic potential of irisolidone in the medicine, numerous scientific research data have been collected from Google, Google Scholar, PubMed, Science Direct, and Scopus. Pharmacological activity data of irisolidone has been collected and analyzed in the present works to know their health beneficial aspects in the medicine. Detailed pharmacological activities of irisolidone have been investigated through scientific data analysis of scientific research works.

RESULTS

Scientific research data analysis of irisolidone revealed the anti-inflammatory, antiangiogenic, anti-cancer, anti-platelet, anti-oxidant, anti-hyperlipidemic, immunomodulating, hepatoprotective and estrogenic potential. However, the biological effect of irisolidone on the gastric system, aldose reductase enzymes, malignant gliomas, and JC virus has also been investigated. Scientific data analysis revealed the significance of analytical tools for the separation and identification of irisolidone.

CONCLUSION

Present work signified the biological importance and therapeutic potential of irisolidone in medicine.

An Electrochemical Sensor Based on Amino Magnetic Nanoparticle-Decorated Graphene for Detection of Cannabidiol

For detection of cannabidiol (CBD)—an important ingredient in Cannabis sativa L.—amino magnetic nanoparticle-decorated graphene (Fe₃O₄-NH₂-GN) was prepared in the form of nanocomposites, and then modified on a glassy carbon electrode (GCE), resulting in a novel electrochemical sensor (Fe₃O₄-NH₂-GN/GCE). The applied Fe₃O₄-NH₂ nanoparticles and GN exhibited typical structures and intended surface groups through characterizations via transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), vibrating sample magnetometer (VSM), and Raman spectroscopy. The Fe₃O₄-NH₂-GN/GCE showed the maximum electrochemical signal for CBD during the comparison of fabricated components via the cyclic voltammetry method, and was systematically investigated in the composition and treatment of components, pH, scan rate, and quantitative analysis ability. Under optimal conditions, the Fe₃O₄-NH₂-GN/GCE exhibited a good detection limit (0.04 μmol L⁻¹) with a linear range of 0.1 μmol L⁻¹ to 100 μmol L⁻¹ (r² = 0.984). In the detection of CBD in the extract of C. sativa leaves, the results of the electrochemical method using the Fe₃O₄-NH₂-GN/GCE were in good agreement with those of the HPLC method. Based on these findings, the proposed sensor could be further developed for the portable and rapid detection of natural active compounds in the food, agricultural, and pharmaceutical fields.

Fabrication of paper-based enzyme immobilized microarray by 3D-printing technique for screening α-glucosidase inhibitors in mulberry leaves and lotus leaves

Background

The discovery of bioactive compounds in traditional Chinese medicine (TCM) has become an important field in TCM modernization. Ligand fishing is a suitable method for discovery of bioactive compounds in complex mixtures such as TCM with high selectivity. Because of unique advantage of low cost and convenience, paper-based microdevices can be good carriers for enzyme immobilized ligand fishing.

Methods

As an important enzyme for glucose metabolism, α-glucosidase was immobilized on polycaprolactone–chitosan-modified paper to prepare the microdevice with unique microfluid structure generated by 3D printing technology, which can be easily applied to screen active compounds in herbal extracts. The preparation conditions of the paper microarray were optimized. The activity of immobilized α-glucosidase was verified by colorimetric reactions which can be easily monitored by cellphone. The paper microarray with α-glucosidase immobilized was used to screen active compounds in the water extracts of mulberry leaves and lotus leaves.

Results

Several key parameters including Na₂CO₃ solution concentration, Na₂CO₃ solution volume, glutaraldehyde concentration, crosslinking time of glutaraldehyde and time of α-glucosidase immobilization were optimized. The proposed paper-based microarray was successfully applied in screening active compounds in two herbal extracts. Four compounds including chlorogenic acid, quercetin-3-O-glucuronide, isoquercetin, and quercetin were identified as α-glucosidase inhibitors. The compounds with significant non-specific adsorption caused by chitosan, such as isoquercitrin, astragalin, quercetin, were also found to be active compounds.

Conclusions

An enzyme immobilized paper microarray was designed and fabricated in this work. Polycaprolactone and chitosan were used to modify filter paper to prepare paper microarrays. Parameters of paper device preparation were optimized. Our findings suggested that 3D-printing paper-based microarrays can be a simple and low-cost approach for discovery of active compounds of TCM.

Electronic supplementary material

The online version of this article (10.1186/s13020-019-0236-y) contains supplementary material, which is available to authorized users.

Preparation of Magnetic Fe₃O₄/MIL-88A Nanocomposite and Its Adsorption Properties for Bromophenol Blue Dye in Aqueous Solution

Metal-organic frameworks (MOFs) are considered as good materials for the adsorption of many environmental pollutants. In this study, magnetic Fe₃O₄/MIL-88A composite was prepared by modification of MIL-88A with magnetic nanoparticles using the coprecipitation method. The structures and magnetic property of magnetic Fe₃O₄/MIL-88A composite were characterized and the adsorption behavior and mechanism for Bromophenol Blue (BPB) were evaluated. The results showed that magnetic Fe₃O₄/MIL-88A composite maintained a hexagonal rod-like structure and has good magnetic responsibility for magnetic separation (the maximum saturation magnetization was 49.8 emu/g). Moreover, the maximum adsorption amount of Fe₃O₄/MIL-88A composite for BPB was 167.2 mg/g and could maintain 94% of the initial adsorption amount after five cycles. The pseudo-second order kinetics and Langmuir isotherm models mostly fitted to the adsorption for BPB suggesting that chemisorption is the rate-limiting step for this monomolecular-layer adsorption. The adsorption capacity for another eight dyes (Bromocresol Green, Brilliant Green, Brilliant Crocein, Amaranth, Fuchsin Basic, Safranine T, Malachite Green and Methyl Red) were also conducted and the magnetic Fe₃O₄/MIL-88A composite showed good adsorption for dyes with sulfonyl groups. In conclusion, magnetic Fe₃O₄/MIL-88A composite could be a promising adsorbent and shows great potential for the removal of anionic dyes containing sulfonyl groups.

Rapid Screening and Identification of BSA Bound Ligands from Radix astragali Using BSA Immobilized Magnetic Nanoparticles Coupled with HPLC-MS

Radix astragali is widely used either as a single herb or as a collection of herbs in a complex prescription in China. In this study, bovine serum albumin functionalized magnetic nanoparticles (BSA-MN) coupled with high performance liquid chromatography-mass spectrometry (HPLC-MS) were used to screen and identify bound ligands from the n-butanol part of a Radix astragali extract. The prepared BSA-MN showed sufficient magnetic response for the separation with an ordinary magnet and satisfied reusability. Fundamental parameters affecting the preparation of BSA-MN and the screening efficiency were studied and optimized. Under the optimum conditions, four bound ligands were screened out from the n-butanol part of a Radix astragali extract and identified as genistin (1), calycosin-7-O-β-d-glucoside (2), ononin (3) and formononetin (4). This effective method could be widely applied for rapid screening and identification of active compounds from complex mixtures without the need for preparative isolation.

Techniques for physicochemical characterization of nanomaterials

Advances in nanotechnology have opened up a new era of diagnosis, prevention and treatment of diseases and traumatic injuries. Nanomaterials, including those with potential for clinical applications, possess novel physicochemical properties that have an impact on their physiological interactions, from the molecular level to the systemic level. There is a lack of standardized methodologies or regulatory protocols for detection or characterization of nanomaterials. This review summarizes the techniques that are commonly used to study the size, shape, surface properties, composition, purity and stability of nanomaterials, along with their advantages and disadvantages. At present there are no FDA guidelines that have been developed specifically for nanomaterial based formulations for diagnostic or therapeutic use. There is an urgent need for standardized protocols and procedures for the characterization of nanoparticles, especially those that are intended for use as theranostics.

Simultaneous ligand fishing and identification of human serum albumin binders from Eucommia ulmoides bark using surface plasmon resonance-high performance liquid chromatography-tandem mass spectrometry

Eucommia ulmoides bark has long been known as tonic herb, however, the systematic biochemical fingerprint analysis and corresponding structural identification are inadequate so far. Here we describe on-line surface plasmon resonance-high performance liquid chromatography-tandem mass spectrometry (SPR-HPLC-MS/MS) to fish out and identify human serum albumin (HSA) binders from E. ulmoides bark. A total of 22 HSA binders, including 4 iridoids, 11 lignans, 3 flavonoids and 4 phenolic acids, were identified or tentatively characterized based on their retention times, UV spectra and MS/MS spectrum with references or literature data, among which, geniposidic acid, geniposide and chlorogenic acid were the predominant HSA binders. In addition, the major characteristic fragmentation pathways of iridoids and lignans were investigated. The higher reusability and stability of the immobilized HSA allow the method cost-effective and high-throughput. Compared with conventional HPLC-MS/MS for chemical fingerprint analysis, SPR-HPLC-MS/MS is simple and easy to provide biochemical fingerprint, moreover, it is easy to identify low-content HSA binders because of the sample clean-up/concentration procedure.