scholarly journals SCREENING AND EVALUATION OF ANTIMICROBIAL ACTIVITY OF THYMUS VULGARIS USING IN VIVO AND IN VITRO METHODS

2016 ◽  
Vol 4 (11) ◽  
pp. 513-522
Author(s):  
YasserM. Kamel ◽  
◽  
AmaniA. Hafez ◽  
WafaaH. Abd-Alla ◽  
◽  
...  
2018 ◽  
Vol 101 (6) ◽  
pp. 1905-1912
Author(s):  
Ayat Jadou ◽  
Ayyad W Al-Shahwany

Abstract Background: Silver nanoparticles (AgNPs) are employed in various applications in the areas of catalysis, optoelectronics, detection and diagnostics, antimicrobials, and therapeutics. Objective: The aim of this work was to study the antimicrobial activity of aqueous and methanolic leaf extracts of Thymus vulgaris and Urtica dioica and biologically prepared silver nanoparticles, as single or in combination treatments, against Escherichia coli and methicillin-resistant Staphylococcus aureus isolates. Methods: The minimum inhibitory concentration (MIC) was quantified by using a microdilution method in sterile 96-well microtiter plates. The assessment of the toxicity of AgNP solutions was evaluated on human blood lymphocyte cells. Results: The results of this study revealed that all AgNP solutions have the lowest MIC values against the bacterial isolates in relation with the methanolic and aqueous extract solutions. However, the results showed that the increasing AgNP concentration was a critical factor influencing the interaction between AgNPs and the human lymphocytes. Conclusions: The cytotoxicity of nanoparticles increased significantly (P < 0.05) at high concentrations. In addition, the biosynthesized AgNPs have an increased antimicrobial activity against all tested bacterial isolates. Highlights: AgNPs have been recognized as an effective antimicrobial agent that exhibits low toxicity in humans and has diverse in vitro and in vivo applications.


Planta Medica ◽  
2015 ◽  
Vol 81 (16) ◽  
Author(s):  
OML Bayazeid ◽  
F Yalcin ◽  
M İlhan ◽  
H Karahan ◽  
E Kupeli-Akkol ◽  
...  
Keyword(s):  

1972 ◽  
Vol 28 (03) ◽  
pp. 351-358
Author(s):  
A.J Baillie ◽  
A. K Sim

SummaryThe activity of several synthetic compounds, rated from good to poor (or inactive) fibrinolytic activators, has been assessed by two different commonly-used in vitro methods. Compounds shown to be active over a narrow concentration range in the hanging clot test were shown to be inhibitors of plasmin and trypsin in the casein-olytic test. The inhibitory activity of these compounds was shown to increase with increasing substrate concentration and apparent activity in the hanging clot test. Possible explanations and relevance of these observations are discussed.


2019 ◽  
Vol 15 (1) ◽  
pp. 63-70
Author(s):  
Shiv Dev Singh ◽  
Arvind Kumar ◽  
Firoz Babar ◽  
Neetu Sachan ◽  
Arun Kumar Sharma

Background: Thienopyrimidines are the bioisoster of quinazoline and unlike quinazoline exist in three isomeric forms corresponding to the three possible types annulation of thiophene to the pyrimidine ring viz thieno[2,3-d] pyrimidine, thieno[3,2-d] pyrimidine and thieno[3,4-d]pyrimidine. Heterocyclic containing the thienopyrimidinone moiety exhibits various pronounced activities such as anti-hypertensive, analgesic and anti-inflammatory, antiviral, platelet aggregation inhibitory, antiprotozoal bronchodilatory, phosphodiesterase inhibitory, antihistaminic, antipsychotic and antimicrobial activity. Objective: Synthesis of novel 3(N,N-dialkylamino)alkyl/phenyl substituted thieno[2,3-d]pyrimidinones as H1-anti-histaminic and antimicrobial agents. Methods: A series of 3-[(N,N-dialkylamino)alkyl/phenyl]-2-(1H)thioxo-5,6,7,8-tetrahydrobenzo(b) thieno(2,3-d)pyrimidine-4(3H)-ones[4a-d], their oxo analogous [5a-d] and 3-[(N,N-dialkylamino)alkyl]- 2-chlorophenyl-5,6,7,8-tetrahydrobenzo(b)thieno(2,3-d)pyrimidine- 4 (3H)-ones[6a-d]derivative were synthesized from 2-amino-4,5,6,7-tetrahydrobenzo(b)thiophene-3-carboxylic acid by nucleophilic substitution of different N,N-dialkyl alkylene/phenylene diamines on activated 3-acylchloride moiety followed by cyclocondensation with carbon disulfide and ethanolic potassium hydroxide to get [4a-d] and in second reaction by condensation with 4-chlorobenzoyl chloride to get [6a-d] by single pot novel innovative route. The oxo analogous [5a-d] were prepared by treating derivatives [4a-d] with potassium permagnate in ethanolic KOH. The synthesized compound were evaluated for H1-antihistaminic and antimicrobial activities. Results: All synthesized compounds exhibited significant H1-antihistaminic activity by in vitro and in vivo screening methods and data were verified analytically and statistically. The compound 4a, 4b, 5a and 5b showed significant H1-antihistaminiic activity than the reference standard chlorpheniramine maleate. The compound 6d, 6c, 5c and 4c exhibited significant antimicrobial activity.


1996 ◽  
Vol 24 (3) ◽  
pp. 325-331
Author(s):  
Iain F. H. Purchase

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhou Fang ◽  
Junjian Chen ◽  
Ye Zhu ◽  
Guansong Hu ◽  
Haoqian Xin ◽  
...  

AbstractPeptides are widely used for surface modification to develop improved implants, such as cell adhesion RGD peptide and antimicrobial peptide (AMP). However, it is a daunting challenge to identify an optimized condition with the two peptides showing their intended activities and the parameters for reaching such a condition. Herein, we develop a high-throughput strategy, preparing titanium (Ti) surfaces with a gradient in peptide density by click reaction as a platform, to screen the positions with desired functions. Such positions are corresponding to optimized molecular parameters (peptide densities/ratios) and associated preparation parameters (reaction times/reactant concentrations). These parameters are then extracted to prepare nongradient mono- and dual-peptide functionalized Ti surfaces with desired biocompatibility or/and antimicrobial activity in vitro and in vivo. We also demonstrate this strategy could be extended to other materials. Here, we show that the high-throughput versatile strategy holds great promise for rational design and preparation of functional biomaterial surfaces.


1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 243-250
Author(s):  
Dag Jenssen ◽  
Lennart Romert

To understand the cause of the biological effects of xenobiotic metabolism in mammals, investigators have traditionally performed animal experiments by comparing the results of biochemical methods, such as measurement of enzyme activity analysis of the metabolites produced, with the observed toxicological effect. This article deals with in vitro methods for genotoxicity combined with drug metabolising preparations at the organelle, cell or organ levels, as exemplified by microsome preparations, isolated cells/cell lines and organ perfusion systems, respectively. The advantage of some of these methods for studying metabolism-mediated mutagenicity is that the measured endpoint reflects not only the bioactivating phase I reactions, but also the detoxifying phase II reactions, and the transfer of the non-conjugated reactive metabolites to other cells and their ability to cause mutations in these cells. In vivo, all these events are important factors in the initiation of cancer. A mechanistic advantage of the methods for metabolism-mediated mutagenicity in vitro is that the relevance of the different steps in metabolism for the mutational events can seldom be investigated in an in vivo assay. Furthermore, human studies can easily be performed using the co-culture technique with isolated human cells or cell lines.


2013 ◽  
Vol 63 (1) ◽  
pp. 19-30 ◽  
Author(s):  
Mohammed Afzal Azam ◽  
Loganathan Dharanya ◽  
Charu Chandrakant Mehta ◽  
Sumit Sachdeva

In the present study, a series of benzothiazol derivatives 3a-l containing pyrazolo[3,4-d]pyrimidine moiety at the second position were synthesized and characterized by analytical and spectral data. The compounds were tested for their in vitro antimicrobial activity. Compounds 1-(1,3-benzothiazol-2- yl)-3-methyl-4-phenyl-1H-pyrazolo[3,4-d]pyrimidine (3a), 1- (1,3-benzothiazol-2-yl)-4-(4-chlorophenyl)-3-methyl-1H-pyrazolo[ 3,4-d]pyrimidine (3d) and 1-(1,3-benzothiazol-2-yl)- 3-methyl-4-substituted phenyl-1H-pyrazolo[3,4-d]pyrimidines (3h-j) showed significant inhibitory activity against P. aeruginosa whereas compounds 1-(1,3-benzothiazol-2-yl)-4- (2-chlorophenyl)-3-methyl-1H-pyrazolo[3,4-d]pyrimidine (3b), 2-[1-(1,3-benzothiazol-2-yl)-3-methyl-1H-pyrazolo[3,4-d]pyrimidin- 4-yl]phenol (3e), 1-(1,3-benzothiazol-2-yl)-4-(3,4-dimethoxyphenyl)- 3-methyl-1H-pyrazolo[3,4-d]pyrimidine (3h), 4-[1-(1,3-benzothiazol-2-yl)-3-methyl-1H-pyrazolo[3,4-d]pyri midin-4-yl]-N,N-dimethylaniline (3j) and 1-(1,3-benzothiazol- 2-yl)-3-methyl-4-[2-phenylvinyl]-1H-pyrazolo[3,4-d]pyrimidine (3k) were found to be active against C. albicans. Some of these synthesized compounds were evaluated for their in vivo acute toxicity, analgesic, anti-inflammatory, and ulcerogenic actions. The tested compound 4-[1-(1,3-benzothiazol- 2-yl)-3-methyl-1H-pyrazolo[3,4-d]pyrimidin-4-yl]-N, N-dimethylaniline (3j) exhibited maximum analgesic and anti-inflammatory activities. Compounds 1-(1,3-benzothiazol- -2-yl)-3-methyl-4-(3-nitrophenyl)-1H-pyrazolo[3,4-d]pyrimidine (3i) and 3j showed a significant gastrointestinal protection compared to the standard drug diclofenac sodium.


1980 ◽  
Vol 152 (6) ◽  
pp. 1596-1609 ◽  
Author(s):  
H W Murray ◽  
Z A Cohn

The capacity of 15 separate populations of mouse peritoneal macrophages to generate and release H2O2 (an index of oxidative metabolism) was compared with their ability to inhibit the intracellular replication of virulent Toxoplasma gondii. Resident macrophages and those elicited by inflammatory agents readily supported toxoplasma multiplication and released 4-20X less H2O2 than macrophages activated in vivo by systemic infection with Bacille Calmette-Guérin or T. gondii, or by immunization with Corynebacterium parvum. Immunologically activated cells consistently displayed both enhanced H2O2 production and antitoxoplasma activity. Exposure to lymphokines generated from cultures of spleen cells from T. gondii immune mice and toxoplasma antigen preserved both the antitoxoplasma activity and the heightened H2O2 release of toxoplasma immune and immune-boosted macrophages, which otherwise were lost after 48-72 h of cultivation. In vitro activation of resident and chemically-elicited cells by 72 h of exposure to mitogen- and antigen-prepared lymphokines, conditions that induce trypanocidal (5) and leishmanicidal activity (14), stimulated O2- and H2O2 release, and enhanced nitroblue tetrazolium reduction in response to toxoplasma ingestion. Such treatment, however, failed to confer any antitoxoplasma activity, indicating that intracellular pathogens may vary in their susceptibility to macrophage microbicidal mechanisms, including specific oxygen intermediates. In contrast, cocultivating normal macrophages with lymphokine plus heart infusion broth for 18H rendered these cells toxoplasmastatic. This in vitro-acquired activity was inhibited by scavengers of O2-, H2O2, OH., and 1O2, demonstrating a role for oxidative metabolites in lymphokine-induced enhancement of macrophage antimicrobial activity. These findings indicate that augmented oxidative metabolism is an consistent marker of macrophage activation, and that oxygen intermediates participate in the resistance of both in vivo- and vitro-activated macrophages toward the intracellular parasite, T. gondii.


Sign in / Sign up

Export Citation Format

Share Document