Methods for Mucin Analysis: A Comparative Study

• Published in: Journal of agricultural and food chemistry 2009-07, Vol.57 (14), p.6029-6035
• Main Authors: Miner-Williams, Warren, Moughan, Paul J, Fuller, Malcolm F
• Format: Article
• Language: English
• Subjects: accuracy; Acetylgalactosamine - analysis; Acetylglucosamine - analysis; Amino Acids - analysis; Analytical Methods; Animals; assays; Biological and medical sciences; casein; Caseins - administration & dosage; Caseins - metabolism; chemical analysis; chemical concentration; Chromatography, Gas; Colorimetry; Diet; Dietary Proteins - administration & dosage; digesta; Digestion; dry matter intake; experimental diets; False Negative Reactions; Food industries; Fundamental and applied biological sciences. Psychology; gas chromatography; glycoproteins; ileum; Ileum - metabolism; intestinal mucosa; mucins; Mucins - analysis; Mucins - metabolism; protein content; Sialic Acids - analysis; Swine; swine feeding
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf901036r

The aim was to compare five techniques commonly used to quantify mucin concentrations in ileal digesta collected from three growing pigs that had been fed a diet in which the sole protein was casein. Ileal mucin output was estimated by the periodic acid−Schiff, ethanol precipitation, and phenol−sulfuric acid methods as 25.1, 19.3, and 20.7 g kg−1 of dry matter intake (DMI), respectively. The mucin concentration estimated from sialic acid was only 5.9 g kg−1 of DMI. On the basis of the concentrations of the hexosamines N-acetylglucosamine and N-acetylgalactosamine, mucin output was estimated as 44.9 g kg−1 pf DMI. Of the five assays studied, the ethanol precipitation, periodic acid−Schiff, phenol−sulfuric acid, and sialic acid methods may considerably underestimate mucin in the digesta, which calls into question the accuracy of all of these approaches. In contrast, the gas chromatography method for the determination of hexosamines gave more information on the type and state of the mucin present.