Novel Kappa Selenocarrageenan Degradation Enzyme Preparation And Application

This paper establishes a new environment-friendly technology and produces a safe and efficient product of seaweed-seleno-oligosaccharides,laying the foundation for its application as an adjuvant medicine for tumor treatment,marine specialty foods,food additives and feed additives.In this study,a novel kappa selenocarrageenan-degrading strain was obtained from seaweed and studied for its preparation,enzymatic properties,degradation characteristics,cytotoxicity and stability.This work obtained a strain of kappa selenocarrageenan and studied the fermentation process and its enzymatic properties:The strain was identified as Pseudoalteromonas sp.by 16S rDNA;The optimum conditions for the fermentation process of the strains were as follows:1.59%κ-carrageenan,3.69 mmol/L Ca²⁺,40°C,and the resulting enzyme activity value was 8.495 U/mL.The effects of temperature,pH,metal ions,surfactants,and protein inhibitors on their enzymatic properties were investigated.The enzyme preparation was obtained by vacuum freeze-drying and immobilization.The vacuum freeze-drying method was firstly discussed.The remaining enzyme activity was used as the index to obtain the best lyophilization process conditions:pre-freezing temperature-40°C,2%trehalose,5 mm enzyme liquid thickness,pre-freezing time 10 h,and the remaining enzyme activity is 50.33%.Study the influence of temperature,air,light and humidity on storage stability.The residual enzyme activity of the lyophilized powder after 30 days of storage under vacuum,-20°C and in the dark,was 36.22%.Next,using sodium alginate as a carrier and glutaraldehyde as a cross-linker,a cross-linked-embedded-crosslinking method was studied.The residual enzyme activity of the immobilized enzyme was 62.83%,with the condition of 3.0%sodium alginate,0.5%glutaraldehyde,3.0%CaCl₂,cross-linking and fixed time for 90 minutes and 120 minutes,respectively.The study of frequency of use showed that the enzyme activity remained more than 70%after repeated use four times,and the free enzyme could only be applied once.After 30 days of alkaline conditions,the remaining enzyme activity was 42.18%,and the free enzyme activity was completely lost under the same conditions.Seleno-oligosaccharide analysis method and its properties:Ultraviolet spectrophotometric method was used to determine the selenium content.The recoveries of total and inorganic selenium were 99.99%and 99.86%,RSD was less than 2%and selenium content was 48.69±0.95μg/g,and the method was simple and the error was small.Compared with kappa selenocarrageenan,seleno-oligosaccharides have a markedly decreased viscosity when their molecular weight decreases.The water solubility increases with increasing temperature and is almost insoluble in organic solvents.Seleno-oligosaccharide application research:Doxorubicin was used as a positive control drug to study its inhibitory effect on tumor cells.The inhibitory effect of seleno-oligosaccharide on Hela cell was higher than that of kappa selenocarrageenan with the same concentration.The preliminary results showed that the seleno-oligosaccharide can be used as an adjuvant drug for tumor treatment.This topic studied the preparation process and stability of a novel kappa selenocarrageenan,and established a mild,easy-to-control process condition for the reaction conditions.The stability of the enzyme preparation is improved and the service life is improved.The stability of the enzyme preparation and the service life is improved.The problems of large molecular weight and low water solubility of kappa selenocarrageenan are improved,which provides a strong theoretical basis for the application and promotion of seaweed selenium polysaccharides.