Study On The Change Law Of Enzyme Activity And Mechanism Of Cell Wall Breaking In Rapeseed Bee Pollen Fermentatio

Bee pollen is collected from angiosperms stamens anther or gymnosperms pollen cells by bee.Bee pollen contains a variety of biological active substances,such as protein,flavonoids,phenols,vitamins,lipids,trace elements,and has the characteristics of low fat,high protein,so is often referred to "nutrition library"and"concentrated nutrition library".It’s is a new type of nutrition and health food products in the 21st century.But the existence of pollen wall redudes the use efficiency of pollen for human body,so the wall must be broken by some methods.At present,the methods to break the pollen wall is mainly physics to break the wall,while the research of using fermentation to break the wall is relatively weak and the breaking-wall mechanism has not yet been reported.The study was used Yeast,Ganoderma lucidum,Pleurotus eryngii and Toadstool to ferment bee rape pollen in order to break pollen wall,and analyze the relationship of the change of enzyme activity and the breaking-wall effect,and then discuss the braking-wall mechanism by fungi in order to provide more theoretical basis and technical support for bee rape pollen to break the wall by fermentation.The fermentation strains was determined by screening,then the best process conditions were determine by optimization.The broken-wall mechanism,which was based on analyzing the relationship between enzyme activity and the rate of broken-wall pollen to was discussed.Finally,the sensory evalutation,nutrition analysis and antioxidant properties of fermentation liquor were completed.The main research contents and results are as follows:(1)screening of fermentation strainsStrains are critical to the broken-wall effect of bee rape pollen.It’s different to the effects of fermentation for Yeast,Ganoderma lucidum,Pleurotus eryngii and Toadstool.From the analysis of nutrition,Ganoderma lucidum is better strain than others,but Yeast is better strain,which is based on the rate of broken-wall pollen,and the rate was reached 79.10±2.05%.(2)The optimization of fermentation processFor the fermentation of Yeast,0.3%was the best content of pollen,and 3mL was the best inoculum dose.The results of Yeast orthogonal experiment were 36℃、8days、pH 5.0 and 140r/min.The test results were that the rate was 84.36±2.79%and the contents of amino acid and polysaccharide were 8.76±0.24 mg/100mL and 14.42±2.77 mg/mL,respectively.For the fermentation of Ganoderma lucidum,0.3%was the best content of pollen.The results of Ganoderma lucidum orthogonal experiment were 30℃、8days、pH 5.5 and 160r/min.The test results were that the rate was 78.02±4.09 and the contents of amino acid and polysaccharide were 11.45±0.68 mg/100mL and 28.61±5.74mg/mL,respectively.(3)The influence of different substrate to enzyme activity and the discuss of the breaking-wall mechanismTo analyzing of combining enzyme activity change with the broken-wall effect,the results show that CMCase,protease and pectinase were related to the broken-wall mechanism.When different substrates were added to the medium,bagasse,which was pretreated by 3%NaOH,is one of the best substrates of induction enzyme activity.When adding bagasse,the broken-wall rate of Ganoderma lucidum and yeast were 85.08±3.92%and 88.31± 2.51%,respectively.Through further analysis,it can be speculated that the pollen broken-wall model is related enzymes firstly open the germinal aperture,then gradually degrade nexine,which compose of cellulose and protein,these give rise to exfoliation of sexine,composing of sporopollenin,and expose the intine.At this time,related enzymes degrade intine,resulting in overflowing of pollen content.(4)The research of sensory evaluation,nutrition analysis and vitro antioxidant of fermented liquors.By studying sensory evaluation,nutrition analysis and antioxidant properties of fermentation liquors,it show that the fermentation liquor of Ganoderma lucidum is better than that yeast on the sensory and nutrition,but on the antioxidant properties,total antioxidant capacity and·OH radical scavenging acticity of yeast fermentation liquor have significant difference,while on the DPPH radical scavenging ability,there was no significant difference.This difference may be related to the types and contents of antioxidants in two liquors.Even though the same kind of antioxidant,its structure may also vary and different structures havedifferent antioxidant mechanism,so their antioxidant properties is also different.