Determination of Plant Proteinase Inhibitors by Agar Gel Radial Diffusion Assay 1

1983 ◽  
Vol 12 (1) ◽  
pp. 255-259 ◽  
Author(s):  
R. H. Shukle ◽  
L. L. Murdock
Keyword(s):  
Proteinase Inhibitors ◽  
Radial Diffusion ◽  
Agar Gel ◽  
Radial Diffusion Assay ◽  
Diffusion Assay

Radial Diffusion as a Simple and Rapid Method for Screening Superoxide Dismutase Activity

1987 ◽  
Vol 24 (5) ◽  
pp. 511-512 ◽  
Author(s):  
A Hunaiti
Keyword(s):  
Superoxide Dismutase ◽  
Biological Samples ◽  
Radial Diffusion ◽  
Superoxide Dismutase Activity ◽  
Superoxide Dismutases ◽  
Medical Applications ◽  
Agar Gel ◽  
Radial Diffusion Assay ◽  
Therapy And Diagnosis ◽  
Diffusion Assay

Superoxide dismutases are of great interest due to their increasing medical applications in therapy and diagnosis of some diseases. The radial diffusion assay was evaluated for its usefulness as a simple, cheap and accurate assay for screening superoxide dismutase activity. In this assay O2− radicals were generated from the interaction of reduced riboflavin with molecular oxygen upon exposure of agar gel containing riboflavin and N,N,N̄,N̄-tetramethylethylene diamine (TEMED) to light. If nitrotctrazolium dye is also present, it will be reduced to the blue insoluble formazan, whilst if superoxide dismutase is present it will prevent this blueing.1 The developed assay was found to give reproducible estimates of pure samples of superoxide dismutase with a lower limit of measurements of about 10 mg. It can be adapted to measure the levels of superoxide dismutase in various crude biological samples.

Mass Spectrometry-Based Identification of Urinary Antimicrobial Peptides in Dairy Cows

2020 ◽  
Vol 27 (3) ◽  
pp. 225-235
Author(s):  
Ambika Sharma ◽  
Rajesh Nigam ◽  
Ashish Kumar ◽  
Simmi Singh
Keyword(s):  
Mass Spectrometry ◽  
Antimicrobial Peptides ◽  
Polyacrylamide Gel Electrophoresis ◽  
Radial Diffusion ◽  
Protein Database ◽  
Antimicrobial Effects ◽  
Cow Urine ◽  
Radial Diffusion Assay ◽  
Promising Source ◽  
Diffusion Assay

Background:: Urine is considered one of the biological fluids in which antimicrobial peptides are secreted or expressed. Cow urine has not been investigated for the presence of these peptides using MALDI-TOF-MS. Objective:: The aim of this study is to isolate, identify and assess the antimicrobial activity of urinary antimicrobial peptides from healthy normal cycling cows. Method:: We analyzed the urine sample using diafiltration, ion exchange chromatography, Reverse Phase High-Performance Liquid Chromatography (RP-HPLC), acid urea polyacrylamide gel electrophoresis (AU-PAGE) coupled with identification through Peptide Mass Fingerprinting (PMF) by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDITOF- MS). The in vitro antimicrobial effects of purified fractions were assessed using Radial Diffusion Assay (RDA) and microtitre broth dilution assay against Gram-positive and Gramnegative bacteria. Results: : Proteins corresponding to the peaks were identified using SWISSPROT protein database. This study revealed constitutive expression of β-Defensin-1 (DEFB1), β-Defensin-4A (DFB4A), Neutrophil Defensin-1 (DEF1), Neutrophil Defensin-3 (DEF3) in cow urine. The identified peptides are cationic antimicrobial peptides of the defensin family. The purified fractions exhibited antimicrobial effects in radial diffusion assay and MIC values in the range of 2.93-29.3 &*#181;M/L. Conclusion:: This study concludes that cow urine, previously unexplored with regard to antimicrobial peptides, would be a promising source of highly potent AMPs and an effective alternative to the resistant antibiotics.

The Measurement of Human Plasma Antiplasmin Activity by Radial Diffusion Assay

1978 ◽  
Vol 39 (02) ◽  
pp. 437-449 ◽  
Author(s):  
W A Andes
Keyword(s):  
Human Plasma ◽  
Antithrombin Iii ◽  
Normal Subjects ◽  
Radial Diffusion ◽  
Physical Methods ◽  
Α2 Macroglobulin ◽  
Radial Diffusion Assay ◽  
Diffusion Assay

SummaryAn assay of human antiplasmins has been developed utilizing radial diffusion of plasma from wells cut in plasmin-enriched, fibrinogen-agarose plates. After diffusion the fibrinogen is clotted. Zones of fibrin protected from background fibrinolysis develop as the result of plasma antiplasmin activity. A pooled plasma standard was taken to contain 100 % antiplasmin activity. Antiplasmin activity of 52 normal subjects varied from 64 to 132 %. Washed platelets contained 1-5 % antiplasmin activity. Using antisera to precipitate individual inhibitors, physical methods of separation, and electrophoresis of plasma in agarose, several different proteins were found to have antiplasmin activity in this assay. Thus, α2-macroglobulin contributed 56%, α1-antitrypsin 20%, antithrombin III 2%, and other proteins 22% of the total antiplasmin activity. 1 ml of whole plasma neutralized 7.0 CTA units of plasmin.

scholarly journals Evaluation of susceptibility of gram-positive and -negative bacteria to human defensins by using radial diffusion assay.

1996 ◽  
Vol 40 (10) ◽  
pp. 2280-2284 ◽  
Author(s):  
H Takemura ◽  
M Kaku ◽  
S Kohno ◽  
Y Hirakata ◽  
H Tanaka ◽  
...  
Keyword(s):  
Bacterial Species ◽  
Antibacterial Activities ◽  
Radial Diffusion ◽  
The Other ◽  
Gram Positive ◽  
Methicillin Resistant ◽  
Rp Hplc ◽  
Radial Diffusion Assay ◽  
Human Defensins ◽  
Diffusion Assay

Defensins are small cationic bactericidal peptides present abundantly in the granules of polymorphonuclear neutrophils (PMNs). Human PMNs contain four defensins termed HNP-1 to HNP-4. We used a new assay system in agar plates, the radial diffusion assay, to evaluate the effects of human defensins against gram-positive and -negative bacteria. A crude mixture of HNP-1, -2, and -3 (crude HNPs) was purified from human PMN extracts by reversed-phase high-pressure liquid chromatography (RP-HPLC). The different components were later separated by RP-HPLC and gel permeation chromatography. We compared the antibacterial activities of purified HNP-1, -2, and -3 against Escherichia coli, Pseudomonas aeruginosa, methicillin-susceptible Staphylococcus aureus, and methicillin-resistant S. aureus strains using the radial diffusion assay. The antibacterial activities of HNP-1 and HNP-2 against all strains tested were similar to those of the crude HNPs, but the activity of HNP-3 was less than those of the other defensins. To quantitate the activities of HNPs against different bacteria, we defined the minimal dose of crude HNPs forming a detectable clear zone around the bacteria as the minimal inhibitory dose (MID) and determined the MIDs for 10 strains of E. coli, 12 strains of P. aeruginosa, 10 strains of methicillin-susceptible S. aureus, and 12 strains of methicillin-resistant S. aureus isolates, including clinical isolates. In general, the MIDs of the HNPs were similar against similar bacterial species. However, the MIDs for P. aeruginosa were higher than those for the other organisms tested. The radial diffusion assay is suitable as a screening test for measuring the susceptibilities of isolates to defensins, because it is sensitive and simple and has good reproducibility.

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