Study on Free Amino Acid and Short Peptide Fertilizer Production by Solid State Fermented Castor Bean Meal

Using microbial fermentation to increase the content of free amino acids and short peptides in the organic fertilizer for castor bean meal can effectively promote plant growth and improve fruit quality.Using free amino acid and short peptide content as an indicator,through single factor and response surface optimization experiments,the process parameters(moisture content,fermentation time and inoculum quantity)of castor meal solid-state fermentation were optimized.The best process parameters for the solid-state fermentation were:the moisture content 62%,the fermentation time 20 d,and the inoculum quantity 0.23%.The moisture content had the greatest impact on the conversion rate of free amino acids and short peptides,and the protein conversion rate reached 65.6%.The scale-up experiment under the optimal conditions showed that the solid-state fermentation using the inoculum had a significant beneficial effect compared with other fermentation methods.The fermentation of castor cake fertilizer provides a theoretical and practical basis for production feasibility,and has important guiding significance for the effective utilization of castor bean meal.

Seven amino acid peptide mimic from HVR1 of HCV influences cytokine profile of immune cells

Objective:To investigate the actions of cytokine profile in the immune cells by a seven amino acid peptide mimic from HVR1 of HCV (GQTYTSG,named 7P).Methods:The peripheral blood mononuclear cells (PBMCs) from 17 healthy blood donors were stimulated with 7P,and the cytokine levels in CD4+CD8-,CD4-CD8+ T cells,NK,NKT cells were analyzed by the intracellular cytokine staining.Results:The frequency of cells which secreted interferon-γ (IFN-γ) was found to be significantly increased in all cells,interleukin-10(IL-10) was significantly increased in CD4+CD8-,CD4-CD8+ T cells but decreased in NK,NKT cells,and tumor necrosis factor-α (TNF-α) was decreased in CD4+CD8-,CD4-CD8+ but increased in NK cells.Conclusion:7P could induce a cytokine profile in different immune cells in vitro and there was some difference between the CD4+CD8-,CD4-CD8+ T cells which represented the adaptive immunity cells and NK,NKT cells which represented the innate immunity cells.This kind of variation of cytokine profile might contribute to anti-virus and anti-inflammatory immune reaction.

SYNTHESIS OF NEW ESTRONE DERIVATIVES OF AMINO ACIDS AND PEPTIDES

A series of estrone derivatives of amino acids and peptides haze been synthesized by different coupling reagents and the binding affinity of deblocked derivatives to the estrogen receptor of rats uteri have been measured by a comptetive radiometric bind- ing assay.

A COMPARISON OF THE DETERMINATION OF STABILITY CONSTANTS OF COMPLEXES OF Cd(Ⅱ)WITH AMINO ACIDS AND SIMPLE PEPTIDES USING MICRO—pH—METRIC TITRATIONS AND CYCLIC VOLTAMMETRY

This paper reports the determination of stability constants for complexes of Cd(Ⅱ)with Gly, Ala,Val,Asp,Gly—Asp,Asp Gly,Gly—Gly and Gly—Gly—Gly using both micro—pH—metric titra- tions and the application of convolution—deconvolution cyclic voltammetry at 25℃ and I=0.10 mol· dm^(-3)(KNO_3).Stability constants were calculated from pH—metric data using the SUPERQUAD com- puter program and cyclic voltammograms were collected,stored and manipulated using the EG and G CONDECON 300 software.A considerably larger ligand:metal ratio(e,g.50:1)was possible using voltammetry.Evaluation of results from the two techniques suggests that stability constants for the species[CdL_2]and[CdL_3]are reliable when calculated fromvoltammetry while those for[CdL]are more reliable when determined by pH-metric titration.

Reversed-phase fused-core HPLC modeling of peptides

Different fused-core stationary phase chemistries（C18,Amide,Phenyl-hexyl and Peptide ES-C18） were used for the analysis of 21 structurally representative model peptides.In addition,the effects of the mobile phase composition（ACN or MeOH as organic modifier;formic acid or acetic acid,as acidifying component） on the column selectivity,peak shape and overall chromatographic performance were evaluated.The RP-amide column,combined with a formic acid-acetonitrile based gradient system,performed as best.A peptide reversed-phase retention model is proposed,consisting of 5 variables：log SumAA,log Sv,clog P,log nHDon and log nHAcc.Quantitative structure-retention relationship（QSRR） models were constructed for 16 different chromatographic systems.The accuracy of this peptide retention model was demonstrated by the comparison between predicted and experimentally obtained retention times,explaining on average 86% of the variability.Moreover,using an external set of 5 validation peptides,the predictive power of the model was also demonstrated.This peptide retention model includes the novel in-silico calculated amino acid descriptor,AA,which was calculated from log P,3D-MoRSE,RDF and WHIM descriptors.

Amino acid identification and sequence analysis of peptides by reaction mass spectrometry

Fast atom bombardment mass spectrometry (FAB-MS) is applied to distinguish N- terminal series ions from C-terminal series ions of a peptide by on-probe acetylation, it provides valuable information about the sequence of an unknown peptide. The FAB mass spectra contain a number of characteristic ions at low-mass region in addition to the sequence ions at high-mass region. It was found that the ions below m/z 200 are characteristic of the amino acid composition of the peptide, from which the amino acid composition of the peptide could be estimated. Additionally, mixture analysis is also discussed.