Effect Of Whey Protein Hydrolysate On The Growth Of Lactobacillus Casei Shirota

Probiotics are viable preparations and its metabolites that invested by improving theecological balance of the host intestinal flora play a useful role, to improve the level of health ofthe host. The probiotics viable cells shall not be less than the number of106CFU/mL in the shelflife, or cannot play the role of the expected improvement in the level of health of the host.Lactobacillus casei Shirota (LCS) nutritional needs demanding, but their proteolytic capacity isweak. In this study, whey protein concentrate (WPC80) be used as the raw material, the trypsinhydrolysis, explore the whey protein hydrolyzate on the growth-promoting effect of Lactobacilluscasei, hoping to find out the main component of whey protein hydrolyzate that to promote thegrowth of lactobacillus casei shirota, as well as providing the theoretical basis for the effective useof whey protein and perfect for the efficient cultivation techniques of lactobacillus casei shirota.The specific content and results are as follows:1. The original broth be activated twice by MRS medium, so that the bacteria vitality fullrecovery. Select culture conditions:37℃--24h, Sampled once every predetermined time,simultaneous determination of the number of viable cells, OD values and pH value. Drawlactobacillus casei shirota growth characteristics curve. The results show that: lactobacillus caseishirota (LCS) enter logarithmic growth phase after4h and arrive after the end of the logarithmicgrowth phase after12h.2. Trypsin hydrolyzed whey protein concentrate80, selecting hydrolysis temperature (°C), theconcentration of the pH value, substrate concentration (g/100mL), Enzyme and substrateconcentration ratio E/S (%) as influencing factors, the degree of hydrolysis as the indicator. Bysingle factor experiment to determine the scope of the better factors, using orthogonal table L49(3),designing orthogonal test. The results show that: in the conditions that: hydrolysis temperature of53℃, pH8.0, E/S3%, the substrate concentration4.0g/100mL, the degree of hydrolysis up to12.67%. 3. The group adding to the WPH, the number of viable cells was significantly higher than thecontrol group(MRS) have increased, in particular, add the hydrolysis time5h and7h effect WPHenrichment of more significant. SDS-PAGE electrophoresis analysis showed that the increase ofhydrolysis time, the protein is gradually enzymatic hydrolysis into small pieces; enrichmentultrafiltration part (F, G) showed the strongest effect of enzymatic degradation products molecularweight of3KD following enrichment.4. Study found that whey protein hydrolyzate varying degrees of growth-promoting effect onlactobacillus casei shirota. To this end, the study compared the the different alternatives amount ofWPH growth of lactobacillus casei shirota. The results show that: the alternative40%, most of thegrowth-promoting effect of lactobacillus casei shirota significantly up to8.58log CFU/mL,respectively, the number of viable cells in the late logarithmic growth phase. Or even up to70%substitution, the number of the viable cell count and viable cell count of the control group is quite.