Study On Probiotics Enrichment And Preparation Of Compound Bacterium

The health effects of probiotics on the human body have been recognized internationally and new functionalities are being continuously researched and developed.Probiotic preparations have been widely used in the food industry.The key indicator for judging the quality of probiotic preparations is the probiotic activity.How to improve the probiotic activity is one of the technical problems that the probiotic industry needs to solve for a long time.At present,the methods for improving the probiotic activity are mainly filtration,centrifugation,dialysis,high osmotic pressure,chemical method,buffered salt method,microencapsulation method,etc.But with the maturation of biofilm technology,enriched microorganisms have been gradually applied from the environmental protection to the food industry and other fields.The advantage is that microorganisms can be continuously enriched on the surface of the carrier and form a biofilm to achieve the purpose of enriching microorganisms.In this study,the principle of biofilm formation was used,and probiotics were used as strains.The best conditions for enriching probiotics by biofilm method were explored through nutrient selection,carrier selection,and research on cultivation methods.Bacterial high-bacterial concentrated bacteria agents provide a basis for its industrialization.The findings are as follows:Choice of nutrients:Five vegetables,celery,lettuce,cabbage,ginger,and carrot,were selected.Each vegetable was beaten with five material-water ratios of 1:1,1:2,1:3,1:4,and 1:5.MRS was used as control.There are four different formulas,namely vegetable slurry,MRS+vegetable slurry,MRS+vegetable filtrate,and MRS+vegetable filter residue.LB,LP,and LR were inoculated and cultured separately,and the pH value,acidity,and viable count were analyzed during the culture.The results showed that the number of viable bacteria in MRS was 9.16 1g,9.51 1g,9.69 1g;the number of viable bacteria in vegetable slurry was 9.62 1g,9.61 1g,9.73 1g;the number of viable bacteria in MRS+vegetable slurry was 10.73 1g,10.70 1g,10.82 1g,and the best effect is a celery slurry with a ratio of 1:3+MRS;MRS+viable bacteria counts in vegetable filtrate 10.52 1g,10.63 1g,10.69 1g;MRS+vegetable filter residue viable counts 9.57 1g,9.83 1g,9.61 1g.Choice of carrier:Firstly,five kinds of carriers such as fiber ball,sponge,Polyester sponge,corn whisker,and sponge gourd were selected.By observing the appearance and scanning electron microscopy,the results showed that the fiber balls had a thick filament-like linear structure;the sponge was more regular and porous.Structure,the pore-like arrangement is relatively regular and uniform;the sponge gourd sponge structure is relatively regular,the texture is relatively hard and difficult to deform;the sponge gourd is a round cylindrical structure with a cylindrical shape;the corn must be a cylindrical structure.Then take Lactobacillus rhamnosus as a strain,co-culture with the selected vector in MRS culture medium,and observe the changes of the bacteria during the cultivation process.The results showed that the pH and acidity of the suspensions with the five carriers were not significantly different from those of the control group,but the number of live bacteria in the suspensions with the carriers was higher than that in the MRS.The number of live bacteria in the MRS was 9.29 1g.The number of liquid bacteria was 9.81 1g,9.78 1g,9.21 1g,9.81 1g,9.45 1g.The number of live bacteria on the carrier was 9.45 1g,9.84 1g,10.37 1g,9.321g,9.54 1g,which shows that the best adhesion effect is sponge sponge.Scanning electron microscopy was used to observe the change of bacteria attachment on the carrier.The results showed that the bacteria had adhered to the carrier at 24 hours.The effect of the adhesion of the bacteria was sponge gourd,corn silk,sponge gourd,fiber ball.However,the time for the carriers to reach the maximum attachment is not same.From the microscopic characterization,it is known that the time to reach the maximum attachment amount is 24 h,24 h,8 h,36 h,24 h.Research on Intermittent Cycle Culture:The best carrier selected in the above experiment was sponge gourd,the nutrient was MRS+(1:3)celery slurry,the strain was selected for Lactobacillus rhamnosus for intermittent culture,the carrier was added to the nutrient,and the nutrient was changed once in 12 hours.Culture at 37?.The pH,acidity,viable count of bacteria suspension,viable count,dry weight,and microscopic characterization of bacteria on the carrier were measured during the culture.The results showed that After the rise,it decreased and then increased to a certain extent.The highest value was 10.34 1g.The increase in the number of viable bacteria in the later period of culture was related to the shedding of bacteria on the carrier.The highest number of viable bacteria on the carrier was 10.37 1g.The dry weight varied from 0.2 to 0.25 g,and microscopic characterization showed that the adhesion of bacteria began to improve at 12 h.Study on Probiotic Biofilm Formation:The carrier and nutrients are the same as above,and the dynamic culture method is adopted to keep the nutrient solution in circulating flow state,and the culture is placed under 37?constant temperature conditions,and the measurement indicators are the same as above.The results showed that the maximum number of live bacteria in the suspension was 10.57 1g,and the maximum number of live bacteria measured on the carrier was 11.73 1g,and the dry weight of the carrier changed from 0.25 to 0.3 g.The microscopic characterization of the bacteria on the carrier showed that at 8 h The bacterial adhesion effect is better,which indicates that the bacterial adhesion effect is significantly better than that of intermittent cycle culture during dynamic culture.Preliminary preparation of probiotics:Dynamic culture was used to enrich the probiotics.After mixing the bacterial membrane with fresh milk,the probiotics were evenly prepared.The number of live bacteria in the probiotics was 11.21 1g.