Method for measuring sulfur-containing amino acid content of Astragali mushroom

Abstract

The invention discloses a method for measuring the sulfur-containing amino acid content of Astragali mushroom, and relates to the field of measurement of amino acid content of the Astragali mushroom.The method comprises the following steps: performing performic acid oxidation protection on the Astragali mushroom serving as a raw material, performing acid hydrolysis, performing ultrafiltration centrifugation, performing derivatization by taking 2,4-dinitrofluorobenzene as a derivatization reagent, performing gradient elution on the obtained derivative sample liquid through high performance liquid chromatography and by taking acetonitrile-water and sodium acetate as flowing phases, detecting under the wavelength of 360 nm, separating derivatives of cysteic acid and methionine sulfone, measuring the peak area of a cystine standard product and a methionine standard product under different concentration gradient, drawing a standard curve, and measuring the cystin content and the methioninecontent separately to obtain the sulfur-containing amino acid content. According to the method, the requirement on instruments is low, the reaction condition does not need to be strictly limited, thequantity of the needed samples is small, the samples are not damaged, single component can be analyzed, and the method is a measuring method which is efficient, accurate, simple, convenient and easyto operate and low in price.

Description

technical field [0001] The invention relates to the field of extraction and content determination of amino acids in Beiqi mushrooms, in particular to a method for measuring the content of sulfur-containing amino acids in Beiqi mushrooms. Background technique [0002] Beiqi mushroom, Pleurotus pleurotus under the Basidiomycota Agaricaceae, Pleurotus pleurotus cultivated for many years with the authentic astragalus leftovers from Hengshan Mountain in Beiyue and a variety of Chinese herbal medicines and crop by-products as culture materials. It is developed in the selenium-rich area of ​​Hunyuan, Shanxi new type of edible fungi. Beiqi mushroom is rich in lysine (1.19g / 100g) and selenium (0.54ppm / 100g) which may be combined with pyrrolysine and L-selenocysteine ​​or L-selenium-methylselenocysteine There is a close relationship with the biosynthesis of amino acid, and it is expected to be developed in the aspects of tumor inhibition, anti-oxidation, adjuvant treatment of cardiov...

AI Technical Summary

Problems solved by technology

However, the -S- bond of sulfur-containing amino acids is easily oxidized and destroyed during conventional protein hydrolysis, and it is easy to undergo oxidation reactions that affect subsequent analysis and detection, and thus cannot be accurately quantitatively analyzed.

[0004] The commonly used hydrolysis method is alkali hydrolysis. The sample is hydrolyzed with KOH, NaOH, etc. at 110°C, but a few amino acids are easy to racemize, and amino acids such as cysteine ​​will be destroyed.

Enzymatic hydrolysis of protein is the use of hydrolytic enzymes to hydrolyze and break the peptide bonds of proteins to generate short peptides or amino acids, but the hydrolysis time is relatively long, and several enzymes need to work together to hydrolyze completely, otherwise the hydrolysis is not complete, resulting in serious problems in the determination of amino acid content. deviation

There are also some determination methods, such as: reduction derivatization method, oxidation method, etc., but most of them have some problems, and only one of the two sulfur-containing amino acids can be determined

[0005] In order to solve the problems that the content determination of sulfur-containing amino acids in Beiqi mushroom is easily disturbed, the results are unreliable, the test conditions are complicated, and the cost is high, the present invention provides a method that is easy to operate, has simple requirements for experimental equipment, and has high content determination accuracy. Method for Determination of Sulfur-Containing Amino Acids in Beiqi Mushroom

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