Quantitative Analysis of the Positional Distribution of Hydroxyproline in Collagenous Gly-Xaa-Yaa Sequences by LC–MS with Partial Acid Hydrolysis and Precolumn Derivatization

Abstract An Improved analytical method based on precolumn derivatization with 9-fluorenylmethyl chloroformate (9-FMC) and reverse- phase liquid chromatography was developed for quantitative analysis of methionine, cysteine, and lysine In feeds. Samples of corn, whey powder, soybean meal, meat meal, and fish meal were selected for an accurate determination of these 3 amino acids. A portion of each finely ground sample was weighed and subjected to oxidation with performic acid for 16 h before hydrolysis with 6N HCI for 24 h. An aliquot of each hydrolysate was evaporated, dissolved, and diluted with 0.2M pH 7.85 borate buffer. An aliquot of each final solution was derlvatlzed with 9-FMC and analyzed by reverse- phase liquid chromatography using a fluorescence detector with a 254 nm excitation filter and a 313 nm emission filter. The 2 sulfur amino acids and lysine were perfectly separated from all other amino acids with a simple binary gradient. Cysteine (analyzed as cysteic acid), methionine (as methionine sulfone), and lysine were quantltated using internal standard calibration. Hydrolysates were also analyzed by conventional Ion-exchange chromatography (IEC). Amino acid values as obtained by the proposed LC method were close to IEC data. Considering IEC results as reference values, the differences In recovery of amino acids In feedstuffs determined by both methods were not more than 7.5%. Precision of the LC method was evaluated within a single hydrolysate and between different hydrolysates of a single sample. Coefficients of variation (CV) were not more than 4.1 and 5.9%, respectively.

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Phosphopeptides Obtained by Partial Acid Hydrolysis of α-Casein2

Journal of the American Chemical Society ◽

10.1021/ja01567a054 ◽

1957 ◽

Vol 79 (10) ◽

pp. 2559-2565 ◽

Cited By ~ 11

Author(s):

N. J. Hipp ◽

M. L. Groves ◽

T. L. McMeekin

Keyword(s):

Acid Hydrolysis ◽

Partial Acid Hydrolysis ◽

Hydrolysis Of

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Preparation of a Novel Glucuronomannan from Auricularia Auricala and its Immunological Activity

Natural Product Communications ◽

10.1177/1934578x1200701124 ◽

2012 ◽

Vol 7 (11) ◽

pp. 1934578X1200701 ◽

Cited By ~ 1

Author(s):

Zonghong Li ◽

Dan Jiang ◽

Hongtao Bi ◽

Dazheng Liu ◽

Sungju Jang ◽

...

Keyword(s):

Nitric Oxide ◽

Acid Hydrolysis ◽

Lymphocyte Proliferation ◽

B Lymphocyte ◽

Glucuronic Acid ◽

Hot Water ◽

Immunological Activity ◽

Partial Acid Hydrolysis ◽

Ft Ir

A glucuronomannan (AA-4-H, Mw around 4 KDa) was prepared from the fruit bodies of Auricularia auricala by extraction with hot water, deproteination by Sevag reagent, stepwise precipitation with ethanol and partial acid hydrolysis. Monosaccharides analysis revealed that AA-4-H consisted of 91% mannose (Man) and 9% glucuronic acid (GlcA). FT-IR, NMR and methylation analyses indicated that AA-4-H is a branched glucuronomannan. Its main chains are composed of 1, 3-linked α-Man p, side chains are single α-Man p or α-GlcA residues attached to the O-2 and O-6 of Man residues of the main chains. Bioassay indicated that AA-4-H remarkably enhanced B lymphocyte proliferation and increased the production of nitric oxide of macrophages in vitro. Thus, glucuronomannan AA-4-H could be explored as a potential immunostimulation agent.

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Structural studies on cross-linked peptides containing lysinonorleucine from elastin of porcine aorta

Canadian Journal of Biochemistry ◽

10.1139/o77-034 ◽

1977 ◽

Vol 55 (3) ◽

pp. 244-248

Author(s):

Maonique Davril ◽

Kia-Ki Han

Keyword(s):

Acid Hydrolysis ◽

Structural Studies ◽

Cross Link ◽

Structural Investigations ◽

Partial Acid Hydrolysis

Three lysinonorleucine peptides were isolated from mature porcine aorta elastin after enzymic digestions and partial acid hydrolysis. The structural investigations which were performed suggest that different regions containing lysinonorleucine may exist. The role of this cross-link in mature elastin is discussed.

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