Table of Contents
What is Folin-Ciocalteu reagent and its role in Lowry method for protein estimation?
Lowry adds phosphomolybdic/phosphotungstic acid also known as Folin-Ciocalteu reagent. This reagent interacts with the cuprous ions and the side chains of tyrosine, tryptophan, and cysteine to produce a blue-green color that can be detected between 650 nm and 750 nm. The protein detection range is 5–100 μg.
What is the principle of Lowry method?
The principle behind the Lowry method of determining protein concentrations lies in the reactivity of the peptide nitrogen[s] with the copper [II] ions under alkaline conditions and the subsequent reduction of the Folin- Ciocalteay phosphomolybdic phosphotungstic acid to heteropolymolybdenum blue by the copper- …
What is Lowry method of protein estimation?
The Lowry protein assay is a biochemical assay for determining the total level of protein in a solution. The total protein concentration is exhibited by a color change of the sample solution in proportion to protein concentration, which can then be measured using colorimetric techniques.
Why is Lowry method better than biuret method?
The Biuret assay is not much good for protein concentrations below 5 mg/ml. By using the Folin-Ciocalteu reagent to detect reduced copper makes the Lowry assay nearly 100 times more sensitive than Biuret reaction alone.
What is the purpose of gallic acid?
Several beneficial effects are reported for gallic acid, including antioxidant, anti-inflammatory, and antineoplastic properties. This compound has been reported to have therapeutic activities in gastrointestinal, neuropsychological, metabolic, and cardiovascular disorders.
What are Bradford and Lowry analytical methods?
The Lowry and Bradford methods are the most widely used dye-binding chromogenic protein assays[4]. The Bradford assay is based on the association of specific amino acid residues, arginine, lysine, and histidine, with non-conjugated groups of Coomassie brilliant blue G-250 dye (CBB) in an acidic environment[5].
What is the difference between biuret and Lowry method?
While the biuret method is sensitive in the range 0.5 to 2.5 mg protein per assay, the Lowry method is 1 to 2 orders of magnitude more sensitive (5 to 150 μg).
Which method is best for protein estimation?
Some of the most frequently used methods for food protein determination are based on analysis of the total nitrogen content in the samples. Examples of such methods are the Dumas method [21] and the Kjeldahl method [15]. In both methods, the total nitrogen in the sample is liberated at high temperature.