ELISA-based competitive trypsin inhibition assay

Inflammation is a complex mechanism in response to any infection, injury, or irritation. The prolonged inflammation leads to tissue damage and loss of function result in various disease conditions like osteoarthritis, and autoimmune diseases like lupus, rheumatoid arthritis, asthma and Crohn’s disease. Anti-inflammatory drugs are used to control inflammatory response and prevent tissue damage .Cyanobacteria are rich sources of phytochemicals like phenolics, flavonoids are known to have anti-inflammatory activity. Because of ease of cultivation and faster growth rate than plants, they are preferred candidates over plants. This study focuses on screening of cyanobacterial isolates for their anti-inflammatory activity. The human erythrocytes (HRBC) membrane stabilization assay indicated the potential of whole cell extracts of cyanobacteria to stabilize lysosomal membrane and thereby prevent tissue damage by lysosomal chemokines and enzymes. The trypsin inhibition assay is an indicator for potential to inhibit proteinases and decelerate tissue damage. The whole cell extracts of 10 cyanobacterial isolates of different genus namely Weistellopsis, Pseudophormidium, Oscillatoria, Nostoc, Phormidium, Chlorella, Hapalosiphon under study showed 85%-94% membrane stabilization in hypotonicity induced hemolysis and 92% to 97% membrane stabilization in heat induced hemolysis. The test extracts also showed 48% to 52% inhibition of trypsin. Thus, the isolates under study have application as anti-inflammatory agent.

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Tropomyosin isoform Tpm3.1 promotes neurite outgrowth in a novel microfluidic device-based neurite outgrowth inhibition assay

10.26226/morressier.5b31ec572afeeb0013459d80 ◽

2018 ◽

Author(s):

Tamara Tomanic

Keyword(s):

Neurite Outgrowth ◽

Microfluidic Device ◽

Inhibition Assay

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Biological assaying of organic compounds in surface waters

Water Science & Technology ◽

10.2166/wst.1994.0518 ◽

1994 ◽

Vol 30 (10) ◽

pp. 113-124 ◽

Cited By ~ 8

Author(s):

L. Guzzella ◽

M. Mingazzini

Keyword(s):

Chemical Analysis ◽

Organic Compounds ◽

Surface Waters ◽

Monitoring Program ◽

Percentage Increase ◽

Inhibition Assay ◽

Extraction Techniques ◽

Pesticide Contamination ◽

Growth Inhibition Assay ◽

Algal Assay

A biological monitoring program (1992-93) was undertaken with the aim of testing the toxic effect of the Lambro, one of the most polluted rivers in Northern Italy. The filtered river samples were tested with S. capricornutum in a 96h exposure growth inhibition assay and with a photobacterial inhibition assay with the LUMISTox System. The unfiltered samples were also tested with LUMISTox, in order to evaluate the role played by the suspended and colloidal material in the water toxicity. The river samples were passed through a series of columns filled with Carbopack B, XAD-2 and C-18 respectively to concentrate organic compound for chemical analysis and enriched with EDTA to complex metals. The Carbopack B procedure proved to be the most efficient among the tested extraction techniques. The de-toxificant effect of the sample treatments was evaluated in terms of percentage increase of the cell density by the algal assay, while the toxicity of the extracted organic compounds was evaluated by LUMISTox System. The comparison of algal assay with chemical analysis results pointed out that the toxicity of the Lambro waters was mainly related to pesticide contamination.

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Evaluation of α-amylase Inhibition and Cytotoxic Activities of the Arachis hypogaea and Cinnamomum tamala

Current Nutrition & Food Science ◽

10.2174/1573401316999200728183434 ◽

2020 ◽

Vol 16 ◽

Author(s):

Deedarul Hyder Sani ◽

Ali Newaz Munna ◽

Mohammad Salim ◽

Md. Jahangir Alam ◽

Md. Jahangir Alam

Keyword(s):

Brine Shrimp ◽

Ethanol Extract ◽

Acetone Extract ◽

Cytotoxic Activities ◽

Inhibition Activity ◽

Inhibition Assay ◽

Peanut Seed ◽

Lc50 Value ◽

Cinnamomum Tamala ◽

Ic50 Value

Background: Diabetes mellitus is the most occurring non-communicable disease resulting in a high blood glucose level. There has been an immense interest in the development of alternative medicines for diabetes treatment, specifically screening functional foods for phytochemicals with the capability of delaying or preventing glucose absorption through digestive enzymes (e.g. α-amylase) inhibition. So, the development of α-amylase inhibitors derived from natural food products is an alternative way to prevent diabetes mellitus Objective: In this study, organic solvent extracts of the Arachis hypogaea (Peanut) and Cinnamomum tamala (Indian bay leaf /Tejpata) were used to investigate their potential α-amylase inhibition and cytotoxic activities through α-amylase inhibition assay and brine shrimp lethality bioassay respectively Method: The α-amylase inhibition assay was performed using the 3,5-dinitrosalicylic acid method for different concentrations of plant extracts. The optical density (OD) of the solutions were measured to determine the inhibition activity at 540 nm using a spectrophotometer. The cytotoxicity of the plant extracts was measured using brine shrimp (Artemia salina) lethality bioassay Results: Among the different organic solvent extracts, peanut seed ethanol extract showed the highest α-amylase inhibition activity (67.68±8.67%) at 1.25 μg/mL concentration with an IC50 value of 0.61 μg/mL which is very close to standard α-amylase inhibitor Acarbose (72.34±4.23%) with an IC50 value of 0.32 μg/mL while acetone extract of Indian bay leaf exhibited the lowest inhibition activity (47.75±1.63%) with an IC50 value of 1.42 μg/mL at the same concentration. Besides, the maximum cytotoxic activity was found in acetone extract of peanut shell with an LC50 value of 57.87 μg/mL whereas ethanol extract of peanut seed showed the lowest cytotoxicity with an LC50 value of 413.90 μg/mL Conclusion: The result of the present work clearly indicates the potentiality of peanut seed ethanol extract to be used in the management of hyperglycemia as it significantly inhibits α-amylase activity while showing less cytotoxic activities

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Characterisation of nitrogen-containing organic compounds by UHPLC-Qtof-MS and anti-amylase activity from the chloroform extract of the bark of Rhizophora mucronata

Future Journal of Pharmaceutical Sciences ◽

10.1186/s43094-021-00283-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

P. Resmi ◽

G. Jitha ◽

Vishnu Murali ◽

Anu Gopinath

Keyword(s):

Diabetes Mellitus ◽

Amylase Activity ◽

Chloroform Extract ◽

Significant Activity ◽

Rhizophora Mucronata ◽

Inhibition Assay ◽

Mangrove Plant ◽

Starting Point ◽

Treatment Of Diabetes ◽

Nitrogen Containing Compounds

Abstract Background Medicinal importance of mangrove plant Rhizophora mucronata, a red mangrove species found in the Asian countries, has long been recognised in traditional systems of medicine. The identification of its phytoconstituents can be a starting point for the drug development. The aim of the work was to extend the current knowledge of phytoconstituents from R. mucronata and to explore its pharmacological importance in the treatment of diabetes mellitus. In the present study, we analysed the chloroform extract from the bark of the mangrove plant R. mucronata for nitrogen-containing constituents using UHPLC QTOF MS profiling, and α-amylase inhibition assay was carried out. Results Four nitrogen-containing compounds were identified from the chloroform extract of the bark of R. mucronata using UHPLC QTOF MS profiling. The compounds identified were N,N′-dicyclohexyl urea, a cryptolepine derivative (C17H15N3O), an aliphatic cyclic compound with hydroxyl and amino groups (C22H43NO), and C16H19NO2 (m/z 258.1495). The anti-amylase activity, an in vitro antidiabetic bioassay, of chloroform extract showed an IC50 value of 220.09 μg/ml. Conclusions This is the first report on the identification of nitrogen-containing compounds from the chloroform extract of the bark of the R. Mucronata. One of the compounds identified was a novel cryptolepine derivative (C16H13N3O), and it falls under the rare category indoloquinoline alkaloid. The chloroform extract also showed significant activity towards α-amylase inhibition assay. Thus, the study has gone some way towards our understanding of the efficacy of bark of the R. mucronata for the treatment of diabetes mellitus and is open for further research.

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Catalytic activity and stereoselectivity of engineered phosphotriesterases towards structurally different nerve agents in vitro

Archives of Toxicology ◽

10.1007/s00204-021-03094-0 ◽

2021 ◽

Author(s):

Anja Köhler ◽

Benjamin Escher ◽

Laura Job ◽

Marianne Koller ◽

Horst Thiermann ◽

...

Keyword(s):

Plasma Clearance ◽

Nerve Agents ◽

Inhibition Assay ◽

Ache Inhibition ◽

Catalytic Activities ◽

Chiral Lc ◽

Hydrolysis Of ◽

Medical Countermeasures

AbstractHighly toxic organophosphorus nerve agents, especially the extremely stable and persistent V-type agents such as VX, still pose a threat to the human population and require effective medical countermeasures. Engineered mutants of the Brevundimonas diminuta phosphotriesterase (BdPTE) exhibit enhanced catalytic activities and have demonstrated detoxification in animal models, however, substrate specificity and fast plasma clearance limit their medical applicability. To allow better assessment of their substrate profiles, we have thoroughly investigated the catalytic efficacies of five BdPTE mutants with 17 different nerve agents using an AChE inhibition assay. In addition, we studied one BdPTE version that was fused with structurally disordered PAS polypeptides to enable delayed plasma clearance and one bispecific BdPTE with broadened substrate spectrum composed of two functionally distinct subunits connected by a PAS linker. Measured kcat/KM values were as high as 6.5 and 1.5 × 108 M−1 min−1 with G- and V-agents, respectively. Furthermore, the stereoselective degradation of VX enantiomers by the PASylated BdPTE-4 and the bispecific BdPTE-7 were investigated by chiral LC–MS/MS, resulting in a several fold faster hydrolysis of the more toxic P(−) VX stereoisomer compared to P(+) VX. In conclusion, the newly developed enzymes BdPTE-4 and BdPTE-7 have shown high catalytic efficacy towards structurally different nerve agents and stereoselectivity towards the toxic P(−) VX enantiomer in vitro and offer promise for use as bioscavengers in vivo.

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The EYTEX™ System and the Neutral Red Uptake Inhibition Assay in Cultured Hep G2 Cells as Alternative Methods for In Vivo Eye Irritation Following the EEC Protocol

Alternatives to Laboratory Animals ◽

10.1177/026119299001700406 ◽

1990 ◽

Vol 17 (4) ◽

pp. 325-333

Author(s):

Paul J. Dierickx ◽

Virginia C. Gordon

Keyword(s):

Neutral Red ◽

Alternative Methods ◽

Inhibition Assay ◽

Hep G2 ◽

Hep G2 Cells ◽

Eye Irritation ◽

Uptake Inhibition ◽

In Vitro Methods ◽

Neutral Red Uptake

The neutral red uptake inhibition assay and the EYTEX™ system were investigated as alternative methods for the assessment of eye irritation, determined according to the EEC protocol. The 17 test chemicals used were mainly organic solvents. The xenobiotics were applied to Hep G2 cells for 24 hours at different concentrations. Neutral red uptake inhibition was then measured. The results are expressed as the NI50 value, which is the concentration of test compound required to induce a 50% reduction in neutral red uptake. The same chemicals were also tested as coded samples by the EYTEX™ test according to the manufacturer's directions. A nearly identical quantitative correlation was found for both in vitro methods with corneal opacity scores: r = 0.84 for EYTEX™ scores and r = 0.83 for log NI50, expressed in μg/ml. Whilst these correlations are certainly not perfect, it is clear that both in vitro methods can be used as valuable prescreening methods.

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Identification and Target-Modification of SL-BBI: A Novel Bowman–Birk Type Trypsin Inhibitor from Sylvirana latouchii

Biomolecules ◽

10.3390/biom10091254 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1254 ◽

Cited By ~ 1

Author(s):

Xi Chen ◽

Dong Chen ◽

Linyuan Huang ◽

Xiaoling Chen ◽

Mei Zhou ◽

...

Keyword(s):

Antimicrobial Activity ◽

Trypsin Inhibitor ◽

Inhibitory Activity ◽

Membrane Damage ◽

Antiproliferative Effects ◽

Docking Simulations ◽

Cell Membrane Damage ◽

Action Mode ◽

Trypsin Inhibition ◽

Cloning Method

The peptides from the ranacyclin family share similar active disulphide loop with plant-derived Bowman–Birk type inhibitors, some of which have the dual activities of trypsin inhibition and antimicrobial. Herein, a novel Bowman–Birk type trypsin inhibitor of the ranacyclin family was identified from the skin secretion of broad-folded frog (Sylvirana latouchii) by molecular cloning method and named as SL-BBI. After chemical synthesis, it was proved to be a potent inhibitor of trypsin with a Ki value of 230.5 nM and showed weak antimicrobial activity against tested microorganisms. Modified analogue K-SL maintains the original inhibitory activity with a Ki value of 77.27 nM while enhancing the antimicrobial activity. After the substitution of active P1 site to phenylalanine and P2′ site to isoleucine, F-SL regenerated its inhibitory activity on chymotrypsin with a Ki value of 309.3 nM and exhibited antiproliferative effects on PC-3, MCF-7 and a series of non-small cell lung cancer cell lines without cell membrane damage. The affinity of F-SL for the β subunits in the yeast 20S proteasome showed by molecular docking simulations enriched the understanding of the possible action mode of Bowman–Birk type inhibitors. Further mechanistic studies have shown that F-SL can activate caspase 3/7 in H157 cells and induce apoptosis, which means it has the potential to become an anticancer agent.

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New derivatives of a natural nordentatin

Open Chemistry ◽

10.1515/chem-2020-0149 ◽

2020 ◽

Vol 18 (1) ◽

pp. 890-897 ◽

Cited By ~ 1

Author(s):

Tin Myo Thant ◽

Nanik Siti Aminah ◽

Alfinda Novi Kristanti ◽

Rico Ramadhan ◽

Hnin Thanda Aung ◽

...

Keyword(s):

Cell Line ◽

Parent Compound ◽

T47d Cell ◽

Positive Control ◽

Inhibition Assay ◽

Anticancer Activities ◽

Methanol Fraction ◽

T47d Cell Line ◽

Ft Ir ◽

Derivatives Of

AbstractNew derivatives were obtained from natural nordentatin (1) previously isolated from the methanol fraction of Clausena excavata by an acylation method. Herein, we report ten new pyranocoumarin derivatives 1a–1j. Their structures were elucidated based on UV-vis, FT-IR, NMR, and DART-MS data. The α-glucosidase inhibition and anticancer activities of nordentatin (1) and its derivatives were also evaluated. The α-glucosidase inhibition assay exhibited that the derivatives 1b, 1d, 1e, 1f, 1h, 1i, and 1j possess higher inhibitory activity for α-glucosidase with IC50 values of 1.54, 9.05, 4.87, 20.25, 12.34, 5.67, and 2.43 mM, whereas acarbose was used as the positive control, IC50 = 7.57 mM. All derivatives exhibited a weak cytotoxicity against a cervical cancer (HeLa) cell line with the IC50 between 0.25 and 1.25 mM. They also showed moderate to low growth inhibition of a breast cancer (T47D) cell line with IC50 values between 0.043 and 1.5 mM, but their activity was lower than that of the parent compound, nordentatin (1) (IC50 = 0.041 mM).

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