Mainly Including Protein, Amino Acid Content Determination And Correlation Analysis

The plant Gynostemma pentaphyllum (Thunb.) Makino, one of more critical wild Chinese medicinal materials, is a kind of Perennialh erbaceous vine which belongs to Cucurbitaeeae.In this experiment, Gynostemma pentaphyllum is chosen as materials. We optimize water-soluble protein extraction process of Gynostemma pentaphyllum by the ultrasonic extraction and study total protein and total acid contents of different organs. At the same time, we research total protein, water-soluble proteins, total amino acids and water-soluble protein amino acid contents of Gynostemma pentaphyllum from different habitats, and correlation analysis between them. The main findings are as follows:1. Total protein contents and the total protein contents of different organs from six provinces are measured using Kjeldahl nitrogen determination. Total protein content of the SC.2is the highest0.238g/g; JP is the lowest of0.102g/gand the average content0.180g/g (18.03%) in17samples. Six provinces, the highest of total protein content of Gynostemma pentaphyllum is Hunan Province,19.88%. The level of total protein content followed by seed> leaves> rhizomes> roots> stems in Ankang, Pingli and total protein content of each part is a significant difference.2. Water-soluble proteins of Gynostemma pentaphyllum ultrasonic extraction process optimize with the factors of extraction temperature, extraction time, extraction power, solid-liquid ratio and the number of extraction and the best extraction conditions:extraction temperature30℃, the solid-liquid ratio1:30, extraction time6min, extraction power360W, extraction three times. The purified effect of water-soluble protein compare the isoelectric point precipitation, ethanol precipitation and ammonium sulfate precipitation, the ammonium sulfate precipitation method is the best protein precipitation with the highest rate of74.8%, also gets higher protein activity and good resoluble.3. Water-soluble protein contents of Gynostemma pentaphyllum, collected from17samples from six provinces, are analyzed. The highest water-soluble protein content is SX.5, up to31.01mg/g, SX.2is the lowest, only9.17mg/g. For the different provinces, Hubei province is the highest of water-soluble protein to27.89mg/g, Hunan Province is the lowest,11.01mg/g. There are no significant differences between provinces. Correlation of total protein content and water-soluble protein content of different samples is not significant (r=0.930).4. We measure and analysis of total amino acids, water-soluble protein amino acid content, and the correlation. Results are as follows:(1)15samples of the six provinces, most of them have seven kinds of essential amino acids, the highest contents of total amino acid and essential amino acids are YN.3,236.34mg/g and92.53mg/g respectively. Total acid content and essential amino acid content of SC.1are the lowest, only52.79mg/g and11.01mg/g, respectively. There are15kinds of amino acid content (except Cys and Lys) in YN.3. Except Cys and Tyr, the rest of the amino acid contents are the lowest in SC.1.17kinds of amino acids, Ala average content is the highest of15.95mg/g, Phe content of essential amino acids is the highest of12.24mg/g. Pairs of the amino acids and amino acids and total protein, between various amino acids, most are a very significant positive correlation, but the correlation is not significant between the protein and amino acids.(2) We measure the total amino acid contents of different parts, the remaining parts are7kinds of essential amino acids except undetected Met in rhizome. Total amino acids contents and essential amino acids contents of Gynostemma pentaphyllum are decreased in the order leaf> seed> rhizomes> stems> roots. Essential amino acids contents in leaves are three times greater than the stem. The vast majority of amino acids in the leaves are the highest, the roots are the lowest. The most of average content of each amino acid is Glu,18.97mg/g, the highest concentrations of essential amino-acid is Phe,12.61mg/g. Using amino acid ratio coefficient method to calculate the RAA, RC and SRC value, combined with the results of EAA/NEAA, EAA/TAA, leaves nutritional value of Gynostemma pentaphyllum are higher than other parts. Each amino acid and amino acid and protein, most amino acids show significant positive correlation. Between Ser, Glu, Gly, Val, Tyr, Phe, Arg and the protein content of various parts of is significantly positive correlation.(3) Water-soluble protein amino acid contents of15samples in six provinces, total amino acids and essential amino acid contents of YN.2are the highest, TAA and EAA contents in SC.2are the lowest.17kinds of amino acids, most of the highest contents are YN.2, YN.3is the lowest. Average content of Cys is up to127.27mg/g, the highest average content of essential amino acids is Val,49.05mg/g. Water-soluble protein amino acid SRC value is low, so nutritional value is limited. The contents of Met+Cys, Phe+Tyr are1-4times greater than the WHO/FAO recommended mode value. Between the vast majorities of water-soluble protein amino acids of Gynostemma pentaphyllum is very significant positive correlation. Only Cys and the others amino acid is significant negative correlation. Total amino acids and water-soluble protein amino acids are not significant.