Bruce Micales bmicales at facstaff.wisc.edu
Sat Feb 11 21:36:11 EST 1995

In article <Pine.ULT.3.91a.950206155636.6438A-100000 at stein1.u.washington.edu> Clay Malinak <malinak at u.washington.edu> writes:
>From: Clay Malinak <malinak at u.washington.edu>
>Newsgroups: bionet.microbiology
>Subject: Kombucha
>Date: Mon, 6 Feb 1995 16:15:44 -0800
>Organization: University of Washington
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Dear Clay,

I do not endorse the use of Kombucha Tea (I am not convinced that it will do 
anything), but due to its composition (microbiological) I am interested in 
this beverage.  Ok, with that said and done here are my answers to your 

>Does anyone have any scientific information on a fermented drink called 
>Kombucha, Kargasok tea or Kvass tea?  It's some sort of culture that's 
>grown on the surface of highly sugared tea.  Users then strain and drink 
>the tea.  Of course, it's supposed to cure cancer, diabetes, Alzheimer's, 
>alcoholism, etc., etc, as well as prevent infections, increase sex drive, 
>provide boundless energy, unclog drains, etc., etc. mad nauseum.
> I'm not a microbiologist, but I can't imagine that anyone with 
>a microscope couldn't tell between these genera just by looking at it.

I understand and this is not a flame, but this is not possible just by looking 
at the culture.  Due to the size difference you can tell differences between a 
yeast and a bacterium, but not be able to identify to genus and species level.
Telling the difference (genus and species) between two bacteria will require 
phenotypic (usually biochemical) testing.  

>So, what I'd like to know is:

>        1. What are the major constituents of the culture?

This is a mixed culture of bacteria and yeast.  It is not a
mushroom.  The microorgansims involved are : Acetobacter xylinium, Acetobacter 
xylinoides, Gluconobacter gluconium. Acetobacter ketogenum, several strains of 
yeasts including some Saacharomyces and Schizosaccharomyces. 

Some names of the bacteria and/or yeast involved may no longer be reconzied.
      2. Are there any _verifiable_, peer-reviewed scientific studies to >     
      support any of the health claims?

I have not been able to find any recent scientific studies.  Some were 
conducted by in the 1920s but that is too long a time.

There have been some studies (according to users of this tea) conducted by the 
Russians, but I do not have the references.

>        3. If this stuff is good (bad?) for you, what is active metabolite 
and/or mechanism of action involved?

Good for you..who knows.  It does contain several C and B vitamins, plus 
glucon- and glucuronic acid.  Of course it also contain acetic acid.  What the 
action these compounds may or may not have is unclear to me.

In conclusion, I would say that this beverage is no worse for you than regular 
tea.  However, since you are using a mixed culture of microorganisms there is 
always the chance that some "nasty" will come along and spoil your fun.  
Therefore, from a microbiologist point of view, if your cannot maintain a 
"pure" mixed culture, I would not use this beverage.

For more info, I would contact the Kombucha Tea Cider Gopher at 
enuxsa.eas.asu.edu 6600.  Or use the internet users international gopher and 
go to Manchuria Tea, Kombucha Tea gopher.    

I hope everything is clear.


Bruce Micales

Bruce Micales
bmicales at facstaff.wisc.edu
Department of Anatomy
Amateur Radio : WA2DEU

"His eyes wide open!"

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