Effect Of Yeasts On Bacterial Cellulose Producted By Gluconacetobacter Europaeus Y9

Nata de coco as a new functional food, it can improve the in digestive system environment, reduce serum cholesterol, lose weight and resist cancer, strong antioxidant activity such as health care function. At present most of Hainan Nata de coco use fermented coconut water preparation medium Nata de coco production, On the one hand is to collect natural, aseptic coconut water is not the reality, it is hard to meet production needs, more important is to fermented a period of time, fermented Nata de coco production is significantly higher than production of nature coconut water. Focuses on screening of high yield strains, the yeasts for BC production and analysis of active ingredients in coconut water. The results are as follows:Nine strains of different sources by Gluconacetobacter spp. the BC production in the NCW (Nature Coconut Water), FCW (Fermentatde Coconut Water) and HS medium. Including Y9strain in FCW medium BC production up to8.16g/L, the rest of the strains were lower than Y9; Y9strain via16SrDNA identification results for Gluconacetobacter europaeus. So choose Y9to do further researchFour yeast strains were isolated from the fermented coconut water:Y1, Y2, Y3and Y4; study their effects of the BC production. The results showed that Y3and Y4fermented liquid can significantly improve the BC production, and the influence of Yl, Y2fermented liquid were not significant. Y4, Y2via Biolog identification results for Kluyveromyces wickerhamii and Pichia ohmeri. So follow experimentexperiment mainly adopts k. wickerhamii to do further research.We also study on yeasts fermentation time and yeast, In addition to selecting k. wickerhamii business also choose Saccharomyces bayanus were compared. Research and the results show that the KW-NC (K. wickerhamii inoculate to NCW) and SB-NC (S. bayanus inoculate to NCW) BC production is highest in48h, respectively is4.48g/L and4.15g/L; yeast in K. wickerhamii and S. bayanus BC production are lower than FCW and adding0.4%and0.7%of ethanol BC production. So yeasts fermented liquid can promote the BC production in48h, while yeast no significant effect of the BC production.Different composition of coconut water using GC/MS analysis. Results showed that the FCW detected a total of25compounds, mainly acids, alcohols and esters. Which types of organic acid reached10, esters7species,2kinds of alcohols. The relative contents of acetic acid to a maximum of31%, followed by n-butyric acid, nitric acid nicotinamide ethyl acetate and ethyl butyrate. Detect the17kinds of compounds in NC, but did not detect the acetic acid. KW-NC detected a total of18kinds of compounds, organic acids species10,2kinds of alcohols. While the FCW and KW-NC acetic acid relative to the highest levels in NCW.Add yeasts respectively to the inoculate to HS, PDA, YPD, bean sprout juice medium, preparation into fermented liquid impact on BC production. The results show that the HS-KW (K wickerhamii inoculate to HS) and HS-SB (S. bayanusi inoculate to HS) can make the BC production have corresponding increase,3.03g/L and3.09g/L. And YPD medium make Y9the highest BC production, respectively is6.91g/L,6.15g/L. NCW and bean sprout juice medium is no significant for Y9BC production.