scholarly journals Extraction and Bioactivity Analysis of Major Flavones Compounds fromScutellaria baicalensisUsing In Vitro Assay and Online Screening HPLC-ABTS System

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Kwang Jin Lee ◽  
Pil Mun Jung ◽  
You-Chang Oh ◽  
Na-Young Song ◽  
Taesoo Kim ◽  
...  

The extraction efficiency of a number of solvent compositions for the improvement of bioactive compounds yield fromS. baicalensishas been investigated. Also, free radical scavengers in the glycoside baicalin (BG), wogonoside (WG), aglycon baicalein (B), and wogonin (W) compounds ofS. baicalensiswere screened, identified, and quantified using coupled offline ABTS and online screening HPLC-ABTS assay. Increasing ethanol content fractions resulted in decreased extract yield of bioactive compounds. In this case, the best yield of 37.01 mg/g in BG, WG, B, and W compounds was obtained by a dipping method with an extraction time of 4 h. In addition, the yield (43.05%) and IC50(34.04 μg/mL) determined through ABTS assay of the 60% aqueous ethanol extract were the most satisfactory of all solvent solutions tested. This result shows that an online screening HPLC-ABTS assay can be a powerful technique for the rapid characterization of bioactivity compounds in plant extracts. Moreover, their anti-inflammatory activities were evaluated via analyzed inhibitory effect on NO and inflammatory cytokine production. Furthermore, WG and W exhibited the strong inhibitory effects on inflammatory mediator production including NO, IL-6, and IL-1βin LPS-stimulated RAW 264.7 macrophages.

2018 ◽  
Vol 13 (1) ◽  
pp. 35 ◽  
Author(s):  
Songül Karakaya ◽  
Hilal Özbek ◽  
Sefa Gözcü ◽  
Zühal Güvenalp ◽  
Hafize Yuca ◽  
...  

<p>Eleven coumarins named osthole (1), imperatorin (2), bergapten (3), prantschimgin (4), grandivitinol (5), suberosin (6), xanthotoxin (7), felamidin (8), marmesin (9), umbelliferone (10), ulopterol (11), and a sterol mixture consisted of stigmasterol (12), β-sitosterol (13) were isolated from the roots of Ferulago blancheana, F. pachyloba and F. trachycarpa through in vitro bioassay-guided fractionation processes. The extracts and bioactive compounds were evaluated for their α-amylase and α-glucosidase activities. Among the tested compounds, felamidin and suberosin showed significant α-glucosidase inhibitory activity with IC<sub>50</sub> values of 0.4 and 0.9 mg/mL, respectively, when compared to the reference standard acarbose (IC<sub>50</sub> = 4.9 mg/mL). Grandivitinol (IC<sub>50</sub> = 20.0 mg/mL) had the lowest inhibitory effect. On the other hand, none of the tested extracts were found to be active on α-amylase inhibition. This is the first report on isolation, characterization of the bioactive compounds and evaluation the α-amylase and α-glucosidase inhibitory activities of these species.</p><p><strong>Video Clip of Methodology</strong>:</p><p>8 min 26 sec:   <a href="https://www.youtube.com/v/x0gakPjgXmc">Full Screen</a>   <a href="https://www.youtube.com/watch?v=x0gakPjgXmc">Alternate</a></p><p> </p>


Lab on a Chip ◽  
2021 ◽  
Author(s):  
YUHAO QIANG ◽  
Jia Liu ◽  
Ming Dao ◽  
E Du

Red blood cells (RBCs) are subjected to recurrent changes in shear stress and oxygen tension during blood circulation. The cyclic shear stress has been identified as an important factor that...


2009 ◽  
Vol 191 (7) ◽  
pp. 2033-2041 ◽  
Author(s):  
Meriyem Aktas ◽  
Franz Narberhaus

ABSTRACT Agrobacterium tumefaciens requires phosphatidylcholine (PC) in its membranes for plant infection. The phospholipid N-methyltransferase PmtA catalyzes all three transmethylation reactions of phosphatidylethanolamine (PE) to PC via the intermediates monomethylphosphatidylethanolamine (MMPE) and dimethylphosphatidylethanolamine (DMPE). The enzyme uses S-adenosylmethionine (SAM) as the methyl donor, converting it to S-adenosylhomocysteine (SAH). Little is known about the activity of bacterial Pmt enzymes, since PC biosynthesis in prokaryotes is rare. In this article, we present the purification and in vitro characterization of A. tumefaciens PmtA, which is a monomeric protein. It binds to PE, the intermediates MMPE and DMPE, the end product PC, and phosphatidylglycerol (PG) and phosphatidylinositol. Binding of the phospholipid substrates precedes binding of SAM. We used a coupled in vitro assay system to demonstrate the enzymatic activity of PmtA and to show that PmtA is inhibited by the end products PC and SAH and the antibiotic sinefungin. The presence of PG stimulates PmtA activity. Our study provides insights into the catalysis and control of a bacterial phospholipid N-methyltransferase.


2003 ◽  
Vol 23 (11) ◽  
pp. 4000-4012 ◽  
Author(s):  
Ludovic Delage ◽  
André Dietrich ◽  
Anne Cosset ◽  
Laurence Maréchal-Drouard

ABSTRACT Some of the mitochondrial tRNAs of higher plants are nuclearly encoded and imported into mitochondria. The import of tRNAs encoded in the nucleus has been shown to be essential for proper protein translation within mitochondria of a variety of organisms. Here, we report the development of an in vitro assay for import of nuclearly encoded tRNAs into plant mitochondria. This in vitro system utilizes isolated mitochondria from Solanum tuberosum and synthetic tRNAs transcribed from cloned nuclear tRNA genes. Although incubation of radioactively labeled in vitro-transcribed tRNAAla, tRNAPhe, and tRNAMet-e with isolated potato mitochondria resulted in importation, as measured by nuclease protection, the amount of tRNA transcripts protected at saturation was at least five times higher for tRNAAla than for the two other tRNAs. This difference in in vitro saturation levels of import is consistent with the in vivo localization of these tRNAs, since cytosolic tRNAAla is naturally imported into potato mitochondria whereas tRNAPhe and tRNAMet-e are not. Characterization of in vitro tRNA import requirements indicates that mitochondrial tRNA import proceeds in the absence of any added cytosolic protein fraction, involves at least one protein component on the surface of mitochondria, and requires ATP-dependent step(s) and a membrane potential.


Author(s):  
Fabrício Freitas Fernandes ◽  
Amanda Latercia Tranches Dias ◽  
Cíntia Lacerda Ramos ◽  
Masaharu Ikegaki ◽  
Antonio Martins de Siqueira ◽  
...  

Cryptococcosis is a worldwide disease caused by the etiological agent Cryptococcus neoformans. It affects mainly immunocompromised humans. It is relatively rare in animals only affecting those that have received prolonged antibiotic therapy. The propolis is a resin that can present several biological properties, including antibacterial, antifungal and antiviral activities. The standard strain C. neoformans ATTC 90112 was used to the antifungal evaluation. The tests were realized with propolis ethanol extract (PEE) G12 in concentrations from 0.1 to 1.6 mg mL-1. The evaluation of MIC and MFC were done according to DUARTE (2002)5. The inhibitory effect of PEE G12 on the fungal growing was seen at the concentration of 0.2 mg mL-1 and 1.6 mg mL-1 was considered a fungicidal one.


2014 ◽  
Vol 50 (4) ◽  
pp. 851-858 ◽  
Author(s):  
Isabela Moreira Baumgratz de Paula ◽  
Flávia Costa Moraes ◽  
Orlando Vieira de Souza ◽  
Célia Hitomi Yamamoto

Rosmarinus officinalis, which belongs to the Lamiaceaefamily, is a species of medicinal flora with therapeutic properties. In order to exploit the benefits of these properties, a mouthwash formulation was developed, with careful selection of raw materials to meet pharmacotechnical requirements. Extracts of the plant were incorporated into a mouthwash, which was shown to have inhibitory action in vitro against the micro-organisms commonly found in periodontics. Controls for assessing the quality of the drugs were carried out, quantifying phenols and flavonoids as chemical markers. Mouthwash solutions were formulated containing 0.1, 5 and 10% ethanol extract of R. officinalis; and 0.05, 5 and 10% of the hexane fraction of R. officinalis. In order to evaluate synergism, ethanol extract and hexane fraction were also added to formulations containing 0.05% sodium fluoride and 0.12% chlorhexidine digluconate. These formulations were assessed for inhibitory effect against the specific microorganisms involved in the process of bacterial plaque formation, S. mutans(ATCC25175) and C. albicans(ATCC 10231), frequently found in cases of oral infections. The agar diffusion method was used to evaluate the inhibitory activity of extracts and formulations. All mouthwash solutions displayed inhibitory activity having higher sensitivity to S. mutansfor the 5% ethanol extract+0.05% sodium fluoride, and greater sensitivity to C. albicansfor the 10% hexane fraction. Results were characterized by the appearance of a growth inhibition halo, justifying the utilization and association of extracts of R. officinalis.


2005 ◽  
Vol 187 (10) ◽  
pp. 3374-3383 ◽  
Author(s):  
Christopher Stead ◽  
An Tran ◽  
Donald Ferguson ◽  
Sara McGrath ◽  
Robert Cotter ◽  
...  

ABSTRACT The lipid A domain anchors lipopolysaccharide (LPS) to the outer membrane and is typically a disaccharide of glucosamine that is both acylated and phosphorylated. The core and O-antigen carbohydrate domains are linked to the lipid A moiety through the eight-carbon sugar 3-deoxy-d-manno-octulosonic acid known as Kdo. Helicobacter pylori LPS has been characterized as having a single Kdo residue attached to lipid A, predicting in vivo a monofunctional Kdo transferase (WaaA). However, using an in vitro assay system we demonstrate that H. pylori WaaA is a bifunctional enzyme transferring two Kdo sugars to the tetra-acylated lipid A precursor lipid IVA. In the present work we report the discovery of a Kdo hydrolase in membranes of H. pylori capable of removing the outer Kdo sugar from Kdo2-lipid A. Enzymatic removal of the Kdo group was dependent upon prior removal of the 1-phosphate group from the lipid A domain, and mass spectrometric analysis of the reaction product confirmed the enzymatic removal of a single Kdo residue by the Kdo-trimming enzyme. This is the first characterization of a Kdo hydrolase involved in the modification of gram-negative bacterial LPS.


2020 ◽  
Vol 32 (10) ◽  
pp. 2515-2519
Author(s):  
Arnannit Kuyyogsuy

In this article, a method for the processing of chitosan from Pacific white shrimp shells is developed which involves three steps viz. demineralization, deproteinization, and deacetylation. The samples of chitosan with more than 90% degree of deacetylation (DD%) were obtained by FTIR. This indicated that the current processing method of shrimp shells was beneficial for chitosan production. The morphology of chitosan sample was determined using scanning electron microscopy (SEM). X-ray diffraction (XRD) patterns exhibited two peaks of crystalline character approximately at 10º and 20º (2θ). The effect of 0.1% (w/v) of chitosan on the growth of Penicillium digitatum was tested by an in vitro assay and the results showed an almost complete inhibition (98% ± 0.56).


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