The Research Of Preparating Newfashioned Biological Feed Additives By Fermenting The Ginkgo Leaves

Ginkgo leaves contain all kinds of active substances such as flavonoids, organic acids,steroids, polysaccharides, amino acids and trace elements. These active substances can have aneffect on the animal body’s metabolism, they play a role in promoting growth of nutrition,disease prevention and disease resistance, and have broad developmenting prospects for theapplication of animals’ feed additives. On the other hand, a lot of waste were generated afterextracting flavonoids and terpenoids from ginkgo leaves, most of them were discarded orburned as waste, it both caused environmental pollution and wasted the residual activeresources of ginkgo leaf residues. In this paper, ginkgo leaves and ginkgo leaf residues wererespectively as the primary fermentation substrates to prepare newfashioned biological feedadditives by solid state fermentation with microorganisms. The main conclusions were asfollows:Ginkgo leaves were as major solid-state fermentation substrates, Bacillus licheniformisand Bacillus natto were respectively as strains. On the basis of single factor tests, weexperiment with fermentation conditions each other through the orthogonal tests of sevenfactors and three levels. The results show that the appropriate fermentation conditions ofBacillus licheniformis were:glucose1.5%(w/v), urea1.5%(w/v), inoculum10%, liquid-solidratio of1.2:1, the initial pH7.0, fermentation temperature37℃, fermentation time48h; theappropriate fermentation conditions of Bacillus natto were:glucose1.5%, urea1.5%(w/v),inoculum10%, liquid-solid ratio of1.2:1, the initial pH7.0, fermentation temperature37℃,fermentation time48h. The contents of flavonoids which were from the culture of Bacilluslicheniformis after fermentation improved16.7%than the culture before fermentation,corresponding the contents of the total amino acids improved17.22%, viable counts reached2.189×1010CFU/g, the formation rate of spores reached82.7%, protease activity reached1307U/g, the contents of the crude proteins improved43.83%, and the total contents of aromaimproved98.68%than the culture before fermentation. The contents of flavonoids which werefrom the culture of Bacillus natto after fermentation improved10.6%than the culture beforefermentation，corresponding the contents of the total amino acids improved31.05%, viablecounts reached2.84×1010CFU/g, the formation rate of spores reached84.2%，protease activityreached1510U/g, the contents of the crude proteins improved58.74%, and the total contents ofaroma improved95.26%than the culture before fermentation. Through biological fermentationand transformation, the two fermentation products not only were rich with probiotics,effectively improved the extraction rate of flavonoids, as well as the contents of crude proteinsand amino acids, but also significantly improved the palatability of feed additives of ginkgoleaves.Ginkgo leaves were as major solid-state fermentation substrates, Bacillus licheniformis andBacillus natto were as strains to conduct mixed fermentation of two strains. Respectivelyconducted the experiments of single factor optimization for liquid-solid ratio, initial pH,inoculum, ratio of strains and fermentation time.The appropriate solid-state fermentationconditions were: liquid-solid ratio of1.2:1, the initial pH7.0, inoculum15%, Bacilluslicheniformis and Bacillus natto composed of1.5:1(V/V) in the two strains, fermentation time5d, viable counts of the culture after fermentation reached12.02×107CFU/g, protease activity reached995U/g.Ginkgo leaf residues were as major solid-state fermentation substrates, Utilis yeast andAspergillus niger were as strains to conduct mixed fermentation of two strains. On the basis ofsingle factor tests, we experimented with fermentation conditions each other through theorthogonal tests of seven factors and three levels. The results show that the appropriatefermentation conditions were: glucose2%(w/v), urea3%(w/v), inoculum15%, liquid-solidratio of1.1:1, the initial pH5.0, fermentation temperature28℃, fermentation time4d. Under thecondition, the viable counts of yeasts reached3.385×109CFU/g, xylanase activity reached87886U/g, cellulase activity reached6465U/g which were from the culture of Utilis yeast andAspergillus niger after fermentation. The contents of amino acids which were from thefermented culture improved95.44%than that before fermentation, corresponding the contentsof the crude proteins improved154.24%, the contents of flavonoids and aroma increasedrespectively96.97%and98.45%. It can significantly improve biological activity, nutritionalvalue, palatability of ginkgo leaf residues by biological fermentation and conversion, and itbroadened the new way of the use of high efficiency and high value of ginkgo leaves.Ginkgo leaf residues were as major solid-state fermentation substrates, Bacilluslicheniformis and Bacillus natto were as fermentation bacterias to conduct mixed fermentationof two strains, respectively conducted the experiments of single factor optimization forliquid-solid ratio, initial pH, inoculum, ratio of strains and fermentation time. The appropriatesolid-state fermentation conditions were: liquid-solid ratio of1.2:1, the initial pH7.0,inoculum15%, Bacillus licheniformis and Bacillus natto composed of1.5:1(V/V) in the twostrains, fermentation time5d. Viable counts of the culture after fermentation reavhed5.62×107CFU/g, protease activity reached816U/g.Ginkgo leaf residues were as raw materials of silage, respectively conducted theexperiments of single factor optimization for moisture content, the amount of Lactobacillus’addition, the amount of glucose’ addition and silage time. The appropriate silage crafts were:moisture content50%, the amount of Lactobacillus’ addition4.5g/kg, the amount of glucose’addition20g/kg, silage time12d. Under the condition, the contents of flavonoids which werefrom the silage samples reached6.5mg/g fresh weight, it improved109.7%than3.1mg/g freshweight which was before silage, while the contents of lactic acids reached404μg/g fresh weight,the content of acid detergent fiber and neutral detergent fiber respectively reached48%and56%, respectively decreased18.6%and11.1%. The results indicated that can significantlyimprove the dissolution rate of flavonoids which were from ginkgo leaf residues by silage andcan effectively reduce the contents of plants’cellulose to help animals to improve the utilizationof the active ingredients and digestibility of plant feed.Ginkgo leaves were as raw materials of silage, respectively conducted the experiments ofsingle factor optimization for moisture content, the amount of Lactobacillus’ addition, theamount of glucose’ addition and silage time. The appropriate silage crafts were: moisturecontent60%, the amount of Lactobacillus’ addition5.5g/kg, the amount of glucose’ addition20g/kg, silage time14d. Under the condition, the contents of flavonoids which were from thesilage samples reached8.9mg/g fresh weight, it improved111.90%than4.2mg/g fresh weightwhich was before silage, while the contents of lactic acids reached652μg/g fresh weight, the content of acid detergent fiber and neutral detergent fiber respectively reached33%and45%,respectively decreased19.5%and15.1%. The results indicated that can significantly improvethe dissolution rate of flavonoids which were from ginkgo leaves by silage and can effectivelyreduce the contents of plants’ cellulose to help animals to improve the utilization of the activeingredients and digestibility of plant feed.Added fermentation of ginkgo leaves which were fermented by Bacillus licheniformis orBacillus natto of0.3%-0.6%to broiler diets that both could improve the feed efficiency ofbroilers in a certain extent (21-42d and1-42d), promote the development of thymus (21d and42d) and spleen (21d). It both could improve the antioxidant function of broilers and theabsorption capacity and tenderness of breast muscle of broilers in a certain extent, the Bacillusnatto is slightly superior to that of Bacillus licheniformis.