Originally published in Mushroom, The Journal, Winter 1994–95
Kombucha is also known as the Manchurian Mushroom, a misnomer because no mushroom species are involved. Kombucha is actually a mixed culture, a symbiotic community of yeasts and bacteria. Recently, the interest in Kombucha has reached a fever pitch, the likes of which I have never seen.
Some days I receive several phone calls asking for it, or information about it. Many New Agers are recommending Kombucha without reservation—and that greatly concerns me.
Kombucha has been around for a very long time. For thousands of years, say some. It spreads during waves of popularity. In the 1920's and then the 1950's several articles in the popular press touted its amazing health stimulating properties. Some attribute its origins to Manchuria others to Tibet, Japan or Eastern Siberia. Its survival seems solely dependent upon human care as no natural colonies have yet been reported.
It's been claimed that Kombucha:
I first was introduced to Kombucha around 1980 when a friend brought me a Mason jar filled with what might be best described as a close relative of the Blob. You know, that corny Sci-fi thriller from the 1950's starring, I think, a very young Steve McQueen. But this Blob seemed a bit more cohesive and since the lid was tightly screwed on, I felt secure from immediate attack.
He passed it on to me with some ceremony, even reverence, in a ritual that had been repeated for centuries. He called it a miracle cure that could fight cancer, slow or reverse the aging process, i.e. a panacea, a remedy for the ailments afflicting human kind. People in Tibet lived into their 100's because of it, he said. The cardinal rule was that it was a gift, never to be sold, but to be cared for and passed on freely to anyone willing to accept it. Anyone who profited from selling it would reap personal disaster and be doomed to a life of ill-fate.
Naturally skeptical, I looked at this gelatinized rubbery goop submerged in water and was completely baffled. What was it? "The Manchurian Mushroom", he replied, smiling enigmatically.
First off, I thought this Blob does not look like any mushroom I had seen - in culture or otherwise. I wondered if he was playing a practical joke. But his sincerity seemed real and he urged me to keep the Kombucha alive by giving it sugar, tea and water. "It came from Tibet" where "monks have used it for hundreds of years".
The story seemed to be getting better. My curiosity now piqued, he drew some of the liquid between puckered lips and passed the Mason jar to me. The Blob was in my court. Reluctantly, I sipped some of the amber fluid surrounding the Blob and swallowed. The flavor was refreshing, reminiscent of fermented apple cider. I felt suddenly paranoid. I had ingested the Blob. The Blob and I were one.
The instructions he left me consisted of two pages of poorly photocopied, badly written, numbered steps. They looked as if they were typed on a vintage Underwood typewriter, circa World War I. Soon, my friend departed. Out of the blue, without request, I had been forced to adopt this strange organism of unknown identity, from an untraceable lineage, of questionable use, with vague instructions and claims too extraordinary to believe. Moreover, the admonitions about the need to keep this thing alive suggested the worst should you be derelict in your duties.
A gelatinous sheath was peeling off from the mother colony. Using a fork I tore off fragments, placing them into their new Mason jar homes. As I discarded the extraneous debris into my sink, I envisioned a monster Blob growing in my septic tank, only to escape at some point to wreak havoc and unimaginable Blobophobia.
One week later, the Blobettes showed significant new growth in all of the Mason jars. I was actually disappointed. I had secretly hoped the things would have died and that would have been the end of it. Now, I had several pet Blobs which surely would consume more time than I could spare. What to do with them? Unwittingly, I had been drawn into servitude to the Blob.
I called Dr. Daniel Stuntz at the University of Washington and asked him if he had heard of this thing. He hadn't. On my next visit to Seattle, I brought him one of the daughter colonies and told him very little about its history.
Naturally inquisitive, Dr. Stuntz took on the Kombucha as a low priority project. Weeks later, he told me it seemed to be a mixture of yeast and bacteria, somehow held together by a mucous membrane of unknown identity. He was totally baffled and asked more questions.
I told him what I could, hesitatingly, because of the extravagant claims. Years later, I heard from others in his laboratory that he was truly mystified, finding that the coexistence of yeasts and bacteria in this gelatinous matrix a highly unusual symbiosis.
The Blob retreated into obscurity until about 10 years later when my friend returned. He quickly asked me where the Manchurian Mushroom was that he had given me? Embarrassed and knowing full well that I may have violated some ancient Tibetan taboo, I confessed that I allowed it to survive through benign neglect for nearly a year and threw it out. I suggested I might have a mammoth colony in my septic tank but wasn't sure.
Not dismayed, but clearly amused, he pulled out another jar! The Blob was Back! There seemed to be no escaping it. I was condemned to grow it again.
Around that time, Andrew Weil and I were trying to get funding for research on medicinal mushrooms. After many futile discussions with vulture-capitalist types, we had come to terms with a well known pharmaceutical screening company who specialized in identifying markets and then would screen microorganisms for new drugs to meet those market niches. Many of the most well known giants in the pharmaceutical industry entrusted them with proprietary strains of microorganisms for enhancement of secondary metabolites. (Metabolites are extra-cellular compounds which have proven to be a rich source of new drugs, especially antibiotics.) Although the screens of the mushrooms were not completely uninteresting, the results fell short of their benchmark of 50% or greater activity in the targeted tests.
The Blobs were quietly fermenting during this period, growing ever larger, soon fully occupying their respective vessels. What the heck, I thought. I made the phone call. Not wanting to tell them what I had—in fact, telling them that the stories surrounding this thing are too incredible to repeat—I asked if they would like to do one more screen. They said yes and one Blob was driven to Seattle for testing.
The initial results took them by surprise. They asked for another sample as a head investigator from the parent company was visiting from Taiwan. Giving them a large test tube (it seemed more scientifically proper to pass it on in a test tube than in a Mason jar), the Blob traveled to Taiwan. Two months passed before I got the next call.
The Blob was indeed interesting, pharmacologically speaking. They wanted to know more about it—how it grew, where it came from, and most particularly What Was It? Their enthusiasm was uncharacteristically unreserved.
Before going further, I consulted with my lawyer who did his lawyer thing - you need contracts protecting proprietary rights, etc.... I expressed to him and others that I felt I had no exclusive rights to the Kombucha, that it was not something I originated.
If I had cloned a new strain from a wild mushroom, then clearly I had taken the essential and unique step of bringing it into culture. The Blob, I felt was not mine but rightfully belonged to some Tibetan monks who centuries ago had taken that critical step. They disagreed. Their position was that many people may know that a plant was useful for a medical purpose but it is the person or group who characterizes, extracts and purifies the active ingredients who deserve proprietary rights.
The phone calls continued. Soon I found myself sitting in a board room of a pharmaceutical company with lawyers and contracts discussing the particulars of patents, sub-licensing agreements, market territories, and dollars running into the millions—if FDA approval was granted for a novel drug. As a whole, the group was, you might say, "straight-laced", conservative, and exceedingly better dressed than I was.
The time had come to lay the cards on the table—the time for full disclosure. I asked them about the results of their tests. "Very interesting" they started. "Our tests show that this thing produces what could be a novel antibiotic, effective against methicillin-resistant strains of Staphylococcus aureus " (The common bacterium responsible for " Staph " infections. Due to the wide use of antibiotics, strains of S. aureus had evolved resistance to many antibiotics.)
The company's benchmark test was designed to discover new antibiotics in the race between science and bacteria's ability to evolve. Their tests did not type the antibiotic produced by the Blob. Later studies, termed "dereplication trials" would serve to match the Blob's antibiotic with those already patented. It may be novel. It may not. If novel, patents could be pursued. To this end, they were willing to spend $50,000-$100,000 immediately on more tests.
Now it was our turn. They asked "What is it?" A long silence ensued. I hated telling them what little I knew. This was not my forte—mushrooms were. I secretly wished one of our mushroom strains would have garnished this much enthusiasm. I was noticeably uncomfortable.
I told them that, as best as we had been able to determine, from analyses by several independent mycologists, that the Blob was a polyculture of at least two yeasts and two bacteria, living synergistically.
The silence was deafening.
Perplexed looks crossed their faces, soon followed by exasperated expressions of deep disappointment. Which of the organisms are producing the potentially novel antibiotic? Was it one or several? Was it one in response to the presence of another organism? Was it one in response to several organisms? The sheer numbers of permutations would complicate trials and given the FDA's disposition, a polyculture is de facto contaminated.
The meeting was abruptly adjourned. Soon thereafter, I received a bill for nearly $10,000 which fortunately, after much haggling, I didn't have to pay. I don't know if they did any more studies. I do know they have a living culture. Go figure.
In some of the articles written on Kombucha, several attempts to list the microorganisms in question. According to one report, The Moscow Central Bacteriological Institute identified the gelatinous mass as Bacterium xylinum and within this matrix lived, in symbiosis, Saccharomyces ludwigii, S. pombe, Bacterium gluconicum, B. xylinoides, B. katogenum,Pichia fermentans, Torula species and "other yeasts". I do not claim to know the validity of these names attested to, but if true, this is one very complex commune of microbes, or one very contaminated culture!
The pH of the Kombucha tea drops from near neutral at make-up to an acidic 2.0-3.0 after grow-out. Alcohol content, a product of yeast fermentation, ranges from .5-1.5%.
In a recent article in The Mycologist, T. Kappel & R. H. Anken (1993) from the University of Stuttgart-Hoheneheim analyzed some of the metabolites. They reported 1% ethyl acetate, 3% acetic acid, lactate, tartrate, fructose, sucrose, various amino acids, biogene amines (ethyl amine, choline, adenine) and carbon dioxide. The ratios of these compounds appeared to related to the ratio of yeasts to bacteria. Others have reported the presence of folic acid, glucoronic acid, l-lactic acid, usnic acid, and vitamins B1, B2, B3, B6 and B12.
In all of my sources, there is no mention as to the natural habitat for Kombucha. One report states that the Kombucha was in use during biblical times. Another states that its first recorded use as "221 BC during the Tsin Dynasty" and that in 414 AD it was brought from Korea to Japan. Although rich in lore, few articles have bibliographies which would help the curious to track down the sources.
A booklet on the Blob, entitled The Tea Fungus: The Natural Remedy and its Significance in Cases of Cancer and other Metabolic Diseases is often quoted. Published by Wilhelm Ennsthaler and apparently coproduced by Rosina Fasching & Dr. Rudolf Sklenar, this document is, for me, hard to take at face value. Subscribing to the school which believes there are cancer viruses, the proper use of Kombucha Tea is tied directly to the study of iridology, where ailments in the human body can be detected by studying the iris. Two addresses are listed if the reader wishes more information. My letters to these addresses went unanswered so I can't be sure if they are valid or not. Probably the best discourse on Kombucha is Kombucha: Healthy Beverage and Natural Remedy From the Far East, by Guenther Frank, in which the dangers of contamination are also noted.
An even more interesting article, whose author requests his name not be used, traces the use of Kombucha in the former Soviet Union. Indeed, even a scandal surfaced when KGB malcontents informed Stalin that his personal physicians were giving him tea contaminated with pathogenic molds in a clever plot of assassination. The version of this article in my possession also lacks a bibliography although several references are cited from studies in the 1920's. Another article, again filled with unreferenced citations, mentions numerous studies from 1915-1929. Even Alexander Solzhenitzyn in his Cancer Ward mentions using Kombucha (grown in a birch-leaf tea) to cure his stomach cancer. The Russians seem to have a rich and long history of Kombucha use.
Despite all of this historical hype, I am bewildered by the current trend where large numbers of individuals would ingest a medicinal compound without any demonstrable need. If you are not sick, why take it?
Some of the claims, such as hair growth and removal of wrinkles, seem to appeal to one's vanity. Other claims, such as curing stomach and intestinal disorders, are interesting but undocumented. Those who might benefit from Kombucha need a credible and experienced professional who could best prescribe and administer it. I do not see the advantage of taking Kombucha by people in good health. Given the detrimental effects seen from prolonged exposure to antibiotics, the repeated, long term use of Kombucha may cause its own universe of problems. I wonder about those people who have adverse reactions to antibiotics? What about those with sensitivity to the microorganisms in Kombucha? I personally believe it is morally reprehensible to pass on this colony to sick or healthy friends when, to date, so little is known about its proper use. At present there are no credible, recent studies as to the safety or usefulness of Kombucha, despite decades of hype.
Many people who are sick are taking Kombucha with false hopes of a miracle cure. If their Kombucha has become contaminated, and they continue drinking it, their spiral into ill-health may actually be exacerbated. In this case, the negative effect of Kombucha use may be masked by the underlying illness for which a cure is sought.
The only claims that make sense to me, and where I have heard anecdotal reports, are that the Kombucha drink, because of its acidity, may aid in digestion, and that topical application of the gelatinous sheath to open wounds, sores, cuts, and abrasions, appears to help wounds heal more quickly. Of course, a contaminated culture would only cause greater infection. In the woods, I think a tube of Neosporin® would be more convenient—and safer—than hiking with a jar filled with bioactive Blob.
One of the major problems with trying to culture Kombucha at home is the fact that the sugar medium is non-selective. The culturing of yogurt or sourdough can be done with a modicum of success, because the milk and flour media selectively favors the desired organisms. Not so with sugar, tea and water which is an "open slate" for the culturing of most microorganisms - including pathogenic Aspergillus, Candida, Cryptococcus, and Fusarium species. The first week is the most critical time during which contaminants in Kombucha race for dominance. As the PH of the broth descends into acidity, the risk of pathogenic organisms proliferating is real and measurable. The primary vectors of contamination are of course, the air. Cheese cloth is an ineffective filtration membrane for preventing airborne contamination. Airborne contamination can be prevented by forcing air through a sub-micron filter, the type which are commonly used in Laminar Flow Hoods in sterile tissue culture. Without such filtration (99.99% at .3 microns), contamination is probable. It is easy to prove this danger by simply pouring the sugar media into sterile Petri dishes (with a gelatinizer like agar agar added). Exposing these dishes briefly to the air in your kitchen will result in a plethora of contamination growth in only 4-5 days. These organisms are made more visible on the surface of the media because of the gelatinizing agent—agar. In liquid culture, they are proliferating even more rapidly, but more invisibly, because they are submerged. The other vectors of contamination are: the mother culture, the insufficiently sterilized media, your hands, and the vessel in which the brew is made.
Few people are aware that more than 1,000,000 particles exceeding .3 microns are floating in the air per cubic foot. These are generally not dangerous unless they become more concentrated or if the impacted human is immunocompromised. Although the majority of these contaminants may not be dangerous, it takes only one pathogenic species proliferating to a toxic level to cause serious harm. Making Kombucha under non-sterile conditions becomes, in a sense, a biological form of Russian Roulette. For those who are ill, drinking Kombucha prepared at home could be one of the worst things they could do!
According to the recipe, I boiled water for 5 minutes to make a Black Tea (Earl Grey also works) fortified with what seemed to be an unusually ample amount of white sugar.
To each liter (quart) of water, after boiling for 5 minutes, add 70 grams (2 1/2 oz) of sugar, add 1 tea bag (= 5 grams or 1/6 oz). Let steep. Once cool, pour about 1/10 equivalent of Kombucha tea as inoculum. Stuff the opening with cotton or gauze. Incubate for 7-10 days at room temperature. The fluid will bubble from carbon dioxide production during the active fermentation period. If not wishing to actively grow Kombucha, the fermenting jars can be stored in the refrigerator for prolonged periods. The gelatinous Blob will soon float on the surface as a cohesive sheath. Older colonies, with a higher density, will shelf off from underneath and sink to the bottom.
Kombucha is unlikely to become contaminated with bacteria if the tea broth has a sufficiently high sucrose content (approximately 10+ percent sugar), making it a naturally inhospitable environment. Furthermore, the tea—with its high acidity, alcohol content and antibiotics—makes bacterial contamination even less probable. Another factor, beyond contamination, is that the extreme acidic nature of the broth has the potential to cause acidosis—a condition where the blood can not adjust its pH. This is one of the suspect causes being investigated with a woman in Iowa who died from drinking Kombucha (See Newsweek, April 25th, 1995, pg. 6). Ironically, the same acidic conditions that prevent bacterial contamination may give rise to its own toxic side-effects.
High acidity of the broth aside, I have seen several of my vessels spontaneously contaminate with molds. Of most concern are the species of Aspergillus I have found floating around with Kombucha. I fear that amateurs could think that by merely pulling out the Aspergillus colonies with a fork, that the culture would be de-contaminated, a dangerous, even deadly presupposition.
The water-soluble toxins of Aspergillus can be highly carcinogenic. Several species are known killers. Since the public can not be expected to distinguish a clean fermented culture from one which is not, I fear that the unreserved use of this tea will result, has resulted in illness, if not death. (See Newsweek, April 25th, 1995, pg. 6.)
Should your Kombucha become contaminated—most often the contaminants are green, pink or black mold-islands floating on the surface of the tea—you can try to re-purify the culture by removing a portion of contiguous sheath and introducing it to a newly prepared batch of tea. Prior to insertion, you should thoroughly wash the sheath with cold water. If the sheath you chose falls apart, then you have likely selected one that is infected. The sheath should have good cohesiveness and feel rubbery to the touch. Once placed into the new batch of tea, incubate as before and watch. The general rule of "when in doubt, throw it out" holds true here. Even with this technique, one should not presume that the Kombucha Blob has been fully purified of contaminants. Herein lies my greatest concern: in all of the "home grown" literature—photocopies, mimeographs, and handwritten sheets—accompanying the many Kombucha samples I have received, not one mentions the possibility of contamination nor methods for re-isolation. Furthermore, with the complex associations between these multiple organisms, it is possible that other bacteria and yeast species may join in the symbiosis with unpredictable effects.
In short, if you are dying from an illness not currently treatable with antibiotics, pure, uncontaminated cultures of Kombucha may help you. Otherwise, I think the danger of misuse should be a prevailing concern for us all.
Frank, Gunther W., 1995. Kombucha: Healthy Beverage and Natural Remedy from the Far East, Publishing House Ennstahler, Steyr.
Kappel, T. & R.H. Anken, 1993. "The Tea Mushroom." Vol. 7 (1) 12-13 The Mycologist.
List, P.H., W. Hufschmidt, 1959. Basische Pilzinhaltstoffer 5. "Uber Biogene Amine und Aminosauren des Teepilizes."Pharma Zenir. Halle Dischl. 98, 594-598.
Pascal, Alana & Van der Kar, Lynne, 1995, Kombucha: How-To and What it's all About, The Van der Kar Press, Malibu, CA.
Skelnar, T. 1984. The Fungus Kombucha. Wilhelm Ennsthaler, Steyr.
A two page circular entitled "Manchurian Mushrooms" is available for $1.00 from the people at The Mushroom Company c/o Jerry & Trish Haugen PO Box, Klamath Falls, Or. 97603.
For more information on Kombucha, you might want to read this report of illness possibly linked to Kombucha, at the Web Site for the Centers for Disease Control and Prevention.